Rust unstable features needed for the kernel #2
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ojeda
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Allocating memory with regulator_list_mutex held makes lockdep unhappy when memory pressure makes the system do fs_reclaim on eg. eMMC using a regulator. Push the lock inside regulator_init_coupling() after the allocation. ====================================================== WARNING: possible circular locking dependency detected 5.7.13+ #533 Not tainted ------------------------------------------------------ kswapd0/383 is trying to acquire lock: cca78ca4 (&sbi->write_io[i][j].io_rwsem){++++}-{3:3}, at: __submit_merged_write_cond+0x104/0x154 but task is already holding lock: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire.part.11+0x40/0x50 fs_reclaim_acquire+0x24/0x28 __kmalloc+0x54/0x218 regulator_register+0x860/0x1584 dummy_regulator_probe+0x60/0xa8 [...] other info that might help us debug this: Chain exists of: &sbi->write_io[i][j].io_rwsem --> regulator_list_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(regulator_list_mutex); lock(fs_reclaim); lock(&sbi->write_io[i][j].io_rwsem); *** DEADLOCK *** 1 lock held by kswapd0/383: #0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 [...] Fixes: d8ca7d1 ("regulator: core: Introduce API for regulators coupling customization") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1a889cf7f61c6429c9e6b34ddcdde99be77a26b6.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
ojeda
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With the conversion of the tree locks to rwsem I got the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc7-00165-g04ec4da5f45f-dirty #922 Not tainted ------------------------------------------------------ compsize/11122 is trying to acquire lock: ffff889fabca8768 (&mm->mmap_lock#2){++++}-{3:3}, at: __might_fault+0x3e/0x90 but task is already holding lock: ffff889fe720fe40 (btrfs-fs-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (btrfs-fs-00){++++}-{3:3}: down_write_nested+0x3b/0x70 __btrfs_tree_lock+0x24/0x120 btrfs_search_slot+0x756/0x990 btrfs_lookup_inode+0x3a/0xb4 __btrfs_update_delayed_inode+0x93/0x270 btrfs_async_run_delayed_root+0x168/0x230 btrfs_work_helper+0xd4/0x570 process_one_work+0x2ad/0x5f0 worker_thread+0x3a/0x3d0 kthread+0x133/0x150 ret_from_fork+0x1f/0x30 -> #1 (&delayed_node->mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_delayed_update_inode+0x50/0x440 btrfs_update_inode+0x8a/0xf0 btrfs_dirty_inode+0x5b/0xd0 touch_atime+0xa1/0xd0 btrfs_file_mmap+0x3f/0x60 mmap_region+0x3a4/0x640 do_mmap+0x376/0x580 vm_mmap_pgoff+0xd5/0x120 ksys_mmap_pgoff+0x193/0x230 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&mm->mmap_lock#2){++++}-{3:3}: __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 __might_fault+0x68/0x90 _copy_to_user+0x1e/0x80 copy_to_sk.isra.32+0x121/0x300 search_ioctl+0x106/0x200 btrfs_ioctl_tree_search_v2+0x7b/0xf0 btrfs_ioctl+0x106f/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: &mm->mmap_lock#2 --> &delayed_node->mutex --> btrfs-fs-00 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(btrfs-fs-00); lock(&delayed_node->mutex); lock(btrfs-fs-00); lock(&mm->mmap_lock#2); *** DEADLOCK *** 1 lock held by compsize/11122: #0: ffff889fe720fe40 (btrfs-fs-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180 stack backtrace: CPU: 17 PID: 11122 Comm: compsize Kdump: loaded Not tainted 5.8.0-rc7-00165-g04ec4da5f45f-dirty #922 Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x165/0x180 __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 ? __might_fault+0x3e/0x90 ? find_held_lock+0x72/0x90 __might_fault+0x68/0x90 ? __might_fault+0x3e/0x90 _copy_to_user+0x1e/0x80 copy_to_sk.isra.32+0x121/0x300 ? btrfs_search_forward+0x2a6/0x360 search_ioctl+0x106/0x200 btrfs_ioctl_tree_search_v2+0x7b/0xf0 btrfs_ioctl+0x106f/0x30a0 ? __do_sys_newfstat+0x5a/0x70 ? ksys_ioctl+0x83/0xc0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The problem is we're doing a copy_to_user() while holding tree locks, which can deadlock if we have to do a page fault for the copy_to_user(). This exists even without my locking changes, so it needs to be fixed. Rework the search ioctl to do the pre-fault and then copy_to_user_nofault for the copying. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
ojeda
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I got the following lockdep splat while testing: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc7-00172-g021118712e59 #932 Not tainted ------------------------------------------------------ btrfs/229626 is trying to acquire lock: ffffffff828513f0 (cpu_hotplug_lock){++++}-{0:0}, at: alloc_workqueue+0x378/0x450 but task is already holding lock: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (&fs_info->scrub_lock){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_scrub_dev+0x11c/0x630 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #6 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_run_dev_stats+0x49/0x480 commit_cowonly_roots+0xb5/0x2a0 btrfs_commit_transaction+0x516/0xa60 sync_filesystem+0x6b/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0xe/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x6d/0xb0 __prepare_exit_to_usermode+0x1cc/0x1e0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #5 (&fs_info->tree_log_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_commit_transaction+0x4bb/0xa60 sync_filesystem+0x6b/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0xe/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x6d/0xb0 __prepare_exit_to_usermode+0x1cc/0x1e0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #4 (&fs_info->reloc_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_record_root_in_trans+0x43/0x70 start_transaction+0xd1/0x5d0 btrfs_dirty_inode+0x42/0xd0 touch_atime+0xa1/0xd0 btrfs_file_mmap+0x3f/0x60 mmap_region+0x3a4/0x640 do_mmap+0x376/0x580 vm_mmap_pgoff+0xd5/0x120 ksys_mmap_pgoff+0x193/0x230 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #3 (&mm->mmap_lock#2){++++}-{3:3}: __might_fault+0x68/0x90 _copy_to_user+0x1e/0x80 perf_read+0x141/0x2c0 vfs_read+0xad/0x1b0 ksys_read+0x5f/0xe0 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (&cpuctx_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 perf_event_init_cpu+0x88/0x150 perf_event_init+0x1db/0x20b start_kernel+0x3ae/0x53c secondary_startup_64+0xa4/0xb0 -> #1 (pmus_lock){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 perf_event_init_cpu+0x4f/0x150 cpuhp_invoke_callback+0xb1/0x900 _cpu_up.constprop.26+0x9f/0x130 cpu_up+0x7b/0xc0 bringup_nonboot_cpus+0x4f/0x60 smp_init+0x26/0x71 kernel_init_freeable+0x110/0x258 kernel_init+0xa/0x103 ret_from_fork+0x1f/0x30 -> #0 (cpu_hotplug_lock){++++}-{0:0}: __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 cpus_read_lock+0x39/0xb0 alloc_workqueue+0x378/0x450 __btrfs_alloc_workqueue+0x15d/0x200 btrfs_alloc_workqueue+0x51/0x160 scrub_workers_get+0x5a/0x170 btrfs_scrub_dev+0x18c/0x630 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: cpu_hotplug_lock --> &fs_devs->device_list_mutex --> &fs_info->scrub_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->scrub_lock); lock(&fs_devs->device_list_mutex); lock(&fs_info->scrub_lock); lock(cpu_hotplug_lock); *** DEADLOCK *** 2 locks held by btrfs/229626: #0: ffff88bfe8bb86e0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: btrfs_scrub_dev+0xbd/0x630 #1: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630 stack backtrace: CPU: 15 PID: 229626 Comm: btrfs Kdump: loaded Not tainted 5.8.0-rc7-00172-g021118712e59 #932 Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x165/0x180 __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 ? alloc_workqueue+0x378/0x450 cpus_read_lock+0x39/0xb0 ? alloc_workqueue+0x378/0x450 alloc_workqueue+0x378/0x450 ? rcu_read_lock_sched_held+0x52/0x80 __btrfs_alloc_workqueue+0x15d/0x200 btrfs_alloc_workqueue+0x51/0x160 scrub_workers_get+0x5a/0x170 btrfs_scrub_dev+0x18c/0x630 ? start_transaction+0xd1/0x5d0 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ? do_sigaction+0x102/0x250 ? lockdep_hardirqs_on_prepare+0xca/0x160 ? _raw_spin_unlock_irq+0x24/0x30 ? trace_hardirqs_on+0x1c/0xe0 ? _raw_spin_unlock_irq+0x24/0x30 ? do_sigaction+0x102/0x250 ? ksys_ioctl+0x83/0xc0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happens because we're allocating the scrub workqueues under the scrub and device list mutex, which brings in a whole host of other dependencies. Because the work queue allocation is done with GFP_KERNEL, it can trigger reclaim, which can lead to a transaction commit, which in turns needs the device_list_mutex, it can lead to a deadlock. A different problem for which this fix is a solution. Fix this by moving the actual allocation outside of the scrub lock, and then only take the lock once we're ready to actually assign them to the fs_info. We'll now have to cleanup the workqueues in a few more places, so I've added a helper to do the refcount dance to safely free the workqueues. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
ojeda
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…emory If the hypervisor doesn't support hugepages, the kernel ends up allocating a large number of page table pages. The early page table allocation was wrongly setting the max memblock limit to ppc64_rma_size with radix translation which resulted in boot failure as shown below. Kernel panic - not syncing: early_alloc_pgtable: Failed to allocate 16777216 bytes align=0x1000000 nid=-1 from=0x0000000000000000 max_addr=0xffffffffffffffff CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-24.9-default+ #2 Call Trace: [c0000000016f3d00] [c0000000007c6470] dump_stack+0xc4/0x114 (unreliable) [c0000000016f3d40] [c00000000014c78c] panic+0x164/0x418 [c0000000016f3dd0] [c000000000098890] early_alloc_pgtable+0xe0/0xec [c0000000016f3e60] [c0000000010a5440] radix__early_init_mmu+0x360/0x4b4 [c0000000016f3ef0] [c000000001099bac] early_init_mmu+0x1c/0x3c [c0000000016f3f10] [c00000000109a320] early_setup+0x134/0x170 This was because the kernel was checking for the radix feature before we enable the feature via mmu_features. This resulted in the kernel using hash restrictions on radix. Rework the early init code such that the kernel boot with memblock restrictions as imposed by hash. At that point, the kernel still hasn't finalized the translation the kernel will end up using. We have three different ways of detecting radix. 1. dt_cpu_ftrs_scan -> used only in case of PowerNV 2. ibm,pa-features -> Used when we don't use cpu_dt_ftr_scan 3. CAS -> Where we negotiate with hypervisor about the supported translation. We look at 1 or 2 early in the boot and after that, we look at the CAS vector to finalize the translation the kernel will use. We also support a kernel command line option (disable_radix) to switch to hash. Update the memblock limit after mmu_early_init_devtree() if the kernel is going to use radix translation. This forces some of the memblock allocations we do before mmu_early_init_devtree() to be within the RMA limit. Fixes: 2bfd65e ("powerpc/mm/radix: Add radix callbacks for early init routines") Reported-by: Shirisha Ganta <shiganta@in.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200828100852.426575-1-aneesh.kumar@linux.ibm.com
ojeda
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…s metrics" test Linux 5.9 introduced perf test case "Parse and process metrics" and on s390 this test case always dumps core: [root@t35lp67 perf]# ./perf test -vvvv -F 67 67: Parse and process metrics : --- start --- metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC parsing metric: inst_retired.any / cpu_clk_unhalted.thread Segmentation fault (core dumped) [root@t35lp67 perf]# I debugged this core dump and gdb shows this call chain: (gdb) where #0 0x000003ffabc3192a in __strnlen_c_1 () from /lib64/libc.so.6 #1 0x000003ffabc293de in strcasestr () from /lib64/libc.so.6 #2 0x0000000001102ba2 in match_metric(list=0x1e6ea20 "inst_retired.any", n=<optimized out>) at util/metricgroup.c:368 #3 find_metric (map=<optimized out>, map=<optimized out>, metric=0x1e6ea20 "inst_retired.any") at util/metricgroup.c:765 #4 __resolve_metric (ids=0x0, map=<optimized out>, metric_list=0x0, metric_no_group=<optimized out>, m=<optimized out>) at util/metricgroup.c:844 #5 resolve_metric (ids=0x0, map=0x0, metric_list=0x0, metric_no_group=<optimized out>) at util/metricgroup.c:881 #6 metricgroup__add_metric (metric=<optimized out>, metric_no_group=metric_no_group@entry=false, events=<optimized out>, events@entry=0x3ffd84fb878, metric_list=0x0, metric_list@entry=0x3ffd84fb868, map=0x0) at util/metricgroup.c:943 #7 0x00000000011034ae in metricgroup__add_metric_list (map=0x13f9828 <map>, metric_list=0x3ffd84fb868, events=0x3ffd84fb878, metric_no_group=<optimized out>, list=<optimized out>) at util/metricgroup.c:988 #8 parse_groups (perf_evlist=perf_evlist@entry=0x1e70260, str=str@entry=0x12f34b2 "IPC", metric_no_group=<optimized out>, metric_no_merge=<optimized out>, fake_pmu=fake_pmu@entry=0x1462f18 <perf_pmu.fake>, metric_events=0x3ffd84fba58, map=0x1) at util/metricgroup.c:1040 #9 0x0000000001103eb2 in metricgroup__parse_groups_test( evlist=evlist@entry=0x1e70260, map=map@entry=0x13f9828 <map>, str=str@entry=0x12f34b2 "IPC", metric_no_group=metric_no_group@entry=false, metric_no_merge=metric_no_merge@entry=false, metric_events=0x3ffd84fba58) at util/metricgroup.c:1082 #10 0x00000000010c84d8 in __compute_metric (ratio2=0x0, name2=0x0, ratio1=<synthetic pointer>, name1=0x12f34b2 "IPC", vals=0x3ffd84fbad8, name=0x12f34b2 "IPC") at tests/parse-metric.c:159 #11 compute_metric (ratio=<synthetic pointer>, vals=0x3ffd84fbad8, name=0x12f34b2 "IPC") at tests/parse-metric.c:189 #12 test_ipc () at tests/parse-metric.c:208 ..... ..... omitted many more lines This test case was added with commit 218ca91 ("perf tests: Add parse metric test for frontend metric"). When I compile with make DEBUG=y it works fine and I do not get a core dump. It turned out that the above listed function call chain worked on a struct pmu_event array which requires a trailing element with zeroes which was missing. The marco map_for_each_event() loops over that array tests for members metric_expr/metric_name/metric_group being non-NULL. Adding this element fixes the issue. Output after: [root@t35lp46 perf]# ./perf test 67 67: Parse and process metrics : Ok [root@t35lp46 perf]# Committer notes: As Ian remarks, this is not s390 specific: <quote Ian> This also shows up with address sanitizer on all architectures (perhaps change the patch title) and perhaps add a "Fixes: <commit>" tag. ================================================================= ==4718==ERROR: AddressSanitizer: global-buffer-overflow on address 0x55c93b4d59e8 at pc 0x55c93a1541e2 bp 0x7ffd24327c60 sp 0x7ffd24327c58 READ of size 8 at 0x55c93b4d59e8 thread T0 #0 0x55c93a1541e1 in find_metric tools/perf/util/metricgroup.c:764:2 #1 0x55c93a153e6c in __resolve_metric tools/perf/util/metricgroup.c:844:9 #2 0x55c93a152f18 in resolve_metric tools/perf/util/metricgroup.c:881:9 #3 0x55c93a1528db in metricgroup__add_metric tools/perf/util/metricgroup.c:943:9 #4 0x55c93a151996 in metricgroup__add_metric_list tools/perf/util/metricgroup.c:988:9 #5 0x55c93a1511b9 in parse_groups tools/perf/util/metricgroup.c:1040:8 #6 0x55c93a1513e1 in metricgroup__parse_groups_test tools/perf/util/metricgroup.c:1082:9 #7 0x55c93a0108ae in __compute_metric tools/perf/tests/parse-metric.c:159:8 #8 0x55c93a010744 in compute_metric tools/perf/tests/parse-metric.c:189:9 #9 0x55c93a00f5ee in test_ipc tools/perf/tests/parse-metric.c:208:2 #10 0x55c93a00f1e8 in test__parse_metric tools/perf/tests/parse-metric.c:345:2 #11 0x55c939fd7202 in run_test tools/perf/tests/builtin-test.c:410:9 #12 0x55c939fd6736 in test_and_print tools/perf/tests/builtin-test.c:440:9 #13 0x55c939fd58c3 in __cmd_test tools/perf/tests/builtin-test.c:661:4 #14 0x55c939fd4e02 in cmd_test tools/perf/tests/builtin-test.c:807:9 #15 0x55c939e4763d in run_builtin tools/perf/perf.c:313:11 #16 0x55c939e46475 in handle_internal_command tools/perf/perf.c:365:8 #17 0x55c939e4737e in run_argv tools/perf/perf.c:409:2 #18 0x55c939e45f7e in main tools/perf/perf.c:539:3 0x55c93b4d59e8 is located 0 bytes to the right of global variable 'pme_test' defined in 'tools/perf/tests/parse-metric.c:17:25' (0x55c93b4d54a0) of size 1352 SUMMARY: AddressSanitizer: global-buffer-overflow tools/perf/util/metricgroup.c:764:2 in find_metric Shadow bytes around the buggy address: 0x0ab9a7692ae0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692af0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 =>0x0ab9a7692b30: 00 00 00 00 00 00 00 00 00 00 00 00 00[f9]f9 f9 0x0ab9a7692b40: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0ab9a7692b50: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0ab9a7692b60: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 00 00 00 00 0x0ab9a7692b70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb Shadow gap: cc </quote> I'm also adding the missing "Fixes" tag and setting just .name to NULL, as doing it that way is more compact (the compiler will zero out everything else) and the table iterators look for .name being NULL as the sentinel marking the end of the table. Fixes: 0a507af ("perf tests: Add parse metric test for ipc metric") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Link: http://lore.kernel.org/lkml/20200825071211.16959-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Yonghong Song says: ==================== Currently, the bpf hashmap iterator takes a bucket_lock, a spin_lock, before visiting each element in the bucket. This will cause a deadlock if a map update/delete operates on an element with the same bucket id of the visited map. To avoid the deadlock, let us just use rcu_read_lock instead of bucket_lock. This may result in visiting stale elements, missing some elements, or repeating some elements, if concurrent map delete/update happens for the same map. I think using rcu_read_lock is a reasonable compromise. For users caring stale/missing/repeating element issues, bpf map batch access syscall interface can be used. Note that another approach is during bpf_iter link stage, we check whether the iter program might be able to do update/delete to the visited map. If it is, reject the link_create. Verifier needs to record whether an update/delete operation happens for each map for this approach. I just feel this checking is too specialized, hence still prefer rcu_read_lock approach. Patch #1 has the kernel implementation and Patch #2 added a selftest which can trigger deadlock without Patch #1. ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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The dev_iommu_priv_set() must be called after probe_device(). This fixes a NULL pointer deference bug when booting a system with kernel cmdline "intel_iommu=on,igfx_off", where the dev_iommu_priv_set() is abused. The following stacktrace was produced: Command line: BOOT_IMAGE=/isolinux/bzImage console=tty1 intel_iommu=on,igfx_off ... DMAR: Host address width 39 DMAR: DRHD base: 0x000000fed90000 flags: 0x0 DMAR: dmar0: reg_base_addr fed90000 ver 1:0 cap 1c0000c40660462 ecap 19e2ff0505e DMAR: DRHD base: 0x000000fed91000 flags: 0x1 DMAR: dmar1: reg_base_addr fed91000 ver 1:0 cap d2008c40660462 ecap f050da DMAR: RMRR base: 0x0000009aa9f000 end: 0x0000009aabefff DMAR: RMRR base: 0x0000009d000000 end: 0x0000009f7fffff DMAR: No ATSR found BUG: kernel NULL pointer dereference, address: 0000000000000038 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.9.0-devel+ #2 Hardware name: LENOVO 20HGS0TW00/20HGS0TW00, BIOS N1WET46S (1.25s ) 03/30/2018 RIP: 0010:intel_iommu_init+0xed0/0x1136 Code: fe e9 61 02 00 00 bb f4 ff ff ff e9 57 02 00 00 48 63 d1 48 c1 e2 04 48 03 50 20 48 8b 12 48 85 d2 74 0b 48 8b 92 d0 02 00 00 48 89 7a 38 ff c1 e9 15 f5 ff ff 48 c7 c7 60 99 ac a7 49 c7 c7 a0 RSP: 0000:ffff96d180073dd0 EFLAGS: 00010282 RAX: ffff8c91037a7d20 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff RBP: ffff96d180073e90 R08: 0000000000000001 R09: ffff8c91039fe3c0 R10: 0000000000000226 R11: 0000000000000226 R12: 000000000000000b R13: ffff8c910367c650 R14: ffffffffa8426d60 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8c9107480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 00000004b100a001 CR4: 00000000003706e0 Call Trace: ? _raw_spin_unlock_irqrestore+0x1f/0x30 ? call_rcu+0x10e/0x320 ? trace_hardirqs_on+0x2c/0xd0 ? rdinit_setup+0x2c/0x2c ? e820__memblock_setup+0x8b/0x8b pci_iommu_init+0x16/0x3f do_one_initcall+0x46/0x1e4 kernel_init_freeable+0x169/0x1b2 ? rest_init+0x9f/0x9f kernel_init+0xa/0x101 ret_from_fork+0x22/0x30 Modules linked in: CR2: 0000000000000038 ---[ end trace 3653722a6f936f18 ]--- Fixes: 01b9d4e ("iommu/vt-d: Use dev_iommu_priv_get/set()") Reported-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Reported-by: Wendy Wang <wendy.wang@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Link: https://lore.kernel.org/linux-iommu/96717683-70be-7388-3d2f-61131070a96a@secunet.com/ Link: https://lore.kernel.org/r/20200903065132.16879-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
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Luo bin says: ==================== hinic: BugFixes The bugs fixed in this patchset have been present since the following commits: patch #1: Fixes: 00e57a6 ("net-next/hinic: Add Tx operation") patch #2: Fixes: 5e126e7 ("hinic: add firmware update support") ==================== Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Nikolay reported a lockdep splat in generic/476 that I could reproduce with btrfs/187. ====================================================== WARNING: possible circular locking dependency detected 5.9.0-rc2+ #1 Tainted: G W ------------------------------------------------------ kswapd0/100 is trying to acquire lock: ffff9e8ef38b6268 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330 but task is already holding lock: ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x65/0x80 slab_pre_alloc_hook.constprop.0+0x20/0x200 kmem_cache_alloc_trace+0x3a/0x1a0 btrfs_alloc_device+0x43/0x210 add_missing_dev+0x20/0x90 read_one_chunk+0x301/0x430 btrfs_read_sys_array+0x17b/0x1b0 open_ctree+0xa62/0x1896 btrfs_mount_root.cold+0x12/0xea legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 vfs_kern_mount.part.0+0x71/0xb0 btrfs_mount+0x10d/0x379 legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 path_mount+0x434/0xc00 __x64_sys_mount+0xe3/0x120 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __mutex_lock+0x7e/0x7e0 btrfs_chunk_alloc+0x125/0x3a0 find_free_extent+0xdf6/0x1210 btrfs_reserve_extent+0xb3/0x1b0 btrfs_alloc_tree_block+0xb0/0x310 alloc_tree_block_no_bg_flush+0x4a/0x60 __btrfs_cow_block+0x11a/0x530 btrfs_cow_block+0x104/0x220 btrfs_search_slot+0x52e/0x9d0 btrfs_lookup_inode+0x2a/0x8f __btrfs_update_delayed_inode+0x80/0x240 btrfs_commit_inode_delayed_inode+0x119/0x120 btrfs_evict_inode+0x357/0x500 evict+0xcf/0x1f0 vfs_rmdir.part.0+0x149/0x160 do_rmdir+0x136/0x1a0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&delayed_node->mutex){+.+.}-{3:3}: __lock_acquire+0x1184/0x1fa0 lock_acquire+0xa4/0x3d0 __mutex_lock+0x7e/0x7e0 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 kthread+0x138/0x160 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &delayed_node->mutex --> &fs_info->chunk_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&fs_info->chunk_mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/100: #0: ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffffa9d65c50 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x115/0x290 #2: ffff9e8e9da260e0 (&type->s_umount_key#48){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0 stack backtrace: CPU: 1 PID: 100 Comm: kswapd0 Tainted: G W 5.9.0-rc2+ #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack+0x92/0xc8 check_noncircular+0x12d/0x150 __lock_acquire+0x1184/0x1fa0 lock_acquire+0xa4/0x3d0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 __mutex_lock+0x7e/0x7e0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? lock_acquire+0xa4/0x3d0 ? btrfs_evict_inode+0x11e/0x500 ? find_held_lock+0x2b/0x80 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 ? _raw_spin_unlock_irqrestore+0x46/0x60 ? add_wait_queue_exclusive+0x70/0x70 ? balance_pgdat+0x670/0x670 kthread+0x138/0x160 ? kthread_create_worker_on_cpu+0x40/0x40 ret_from_fork+0x1f/0x30 This is because we are holding the chunk_mutex when we call btrfs_alloc_device, which does a GFP_KERNEL allocation. We don't want to switch that to a GFP_NOFS lock because this is the only place where it matters. So instead use memalloc_nofs_save() around the allocation in order to avoid the lockdep splat. Reported-by: Nikolay Borisov <nborisov@suse.com> CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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…arnings Since commit 845e0eb ("net: change addr_list_lock back to static key"), cascaded DSA setups (DSA switch port as DSA master for another DSA switch port) are emitting this lockdep warning: ============================================ WARNING: possible recursive locking detected 5.8.0-rc1-00133-g923e4b5032dd-dirty #208 Not tainted -------------------------------------------- dhcpcd/323 is trying to acquire lock: ffff000066dd4268 (&dsa_master_addr_list_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0x44/0x90 but task is already holding lock: ffff00006608c268 (&dsa_master_addr_list_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0x44/0x90 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dsa_master_addr_list_lock_key/1); lock(&dsa_master_addr_list_lock_key/1); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by dhcpcd/323: #0: ffffdbd1381dda18 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x24/0x30 #1: ffff00006614b268 (_xmit_ETHER){+...}-{2:2}, at: dev_set_rx_mode+0x28/0x48 #2: ffff00006608c268 (&dsa_master_addr_list_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0x44/0x90 stack backtrace: Call trace: dump_backtrace+0x0/0x1e0 show_stack+0x20/0x30 dump_stack+0xec/0x158 __lock_acquire+0xca0/0x2398 lock_acquire+0xe8/0x440 _raw_spin_lock_nested+0x64/0x90 dev_mc_sync+0x44/0x90 dsa_slave_set_rx_mode+0x34/0x50 __dev_set_rx_mode+0x60/0xa0 dev_mc_sync+0x84/0x90 dsa_slave_set_rx_mode+0x34/0x50 __dev_set_rx_mode+0x60/0xa0 dev_set_rx_mode+0x30/0x48 __dev_open+0x10c/0x180 __dev_change_flags+0x170/0x1c8 dev_change_flags+0x2c/0x70 devinet_ioctl+0x774/0x878 inet_ioctl+0x348/0x3b0 sock_do_ioctl+0x50/0x310 sock_ioctl+0x1f8/0x580 ksys_ioctl+0xb0/0xf0 __arm64_sys_ioctl+0x28/0x38 el0_svc_common.constprop.0+0x7c/0x180 do_el0_svc+0x2c/0x98 el0_sync_handler+0x9c/0x1b8 el0_sync+0x158/0x180 Since DSA never made use of the netdev API for describing links between upper devices and lower devices, the dev->lower_level value of a DSA switch interface would be 1, which would warn when it is a DSA master. We can use netdev_upper_dev_link() to describe the relationship between a DSA slave and a DSA master. To be precise, a DSA "slave" (switch port) is an "upper" to a DSA "master" (host port). The relationship is "many uppers to one lower", like in the case of VLAN. So, for that reason, we use the same function as VLAN uses. There might be a chance that somebody will try to take hold of this interface and use it immediately after register_netdev() and before netdev_upper_dev_link(). To avoid that, we do the registration and linkage while holding the RTNL, and we use the RTNL-locked cousin of register_netdev(), which is register_netdevice(). Since this warning was not there when lockdep was using dynamic keys for addr_list_lock, we are blaming the lockdep patch itself. The network stack _has_ been using static lockdep keys before, and it _is_ likely that stacked DSA setups have been triggering these lockdep warnings since forever, however I can't test very old kernels on this particular stacked DSA setup, to ensure I'm not in fact introducing regressions. Fixes: 845e0eb ("net: change addr_list_lock back to static key") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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syzbot reported twice a lockdep issue in fib6_del() [1]
which I think is caused by net->ipv6.fib6_null_entry
having a NULL fib6_table pointer.
fib6_del() already checks for fib6_null_entry special
case, we only need to return earlier.
Bug seems to occur very rarely, I have thus chosen
a 'bug origin' that makes backports not too complex.
[1]
WARNING: suspicious RCU usage
5.9.0-rc4-syzkaller #0 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1996 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
4 locks held by syz-executor.5/8095:
#0: ffffffff8a7ea708 (rtnl_mutex){+.+.}-{3:3}, at: ppp_release+0x178/0x240 drivers/net/ppp/ppp_generic.c:401
#1: ffff88804c422dd8 (&net->ipv6.fib6_gc_lock){+.-.}-{2:2}, at: spin_trylock_bh include/linux/spinlock.h:414 [inline]
#1: ffff88804c422dd8 (&net->ipv6.fib6_gc_lock){+.-.}-{2:2}, at: fib6_run_gc+0x21b/0x2d0 net/ipv6/ip6_fib.c:2312
#2: ffffffff89bd6a40 (rcu_read_lock){....}-{1:2}, at: __fib6_clean_all+0x0/0x290 net/ipv6/ip6_fib.c:2613
#3: ffff8880a82e6430 (&tb->tb6_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:359 [inline]
#3: ffff8880a82e6430 (&tb->tb6_lock){+.-.}-{2:2}, at: __fib6_clean_all+0x107/0x290 net/ipv6/ip6_fib.c:2245
stack backtrace:
CPU: 1 PID: 8095 Comm: syz-executor.5 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fd lib/dump_stack.c:118
fib6_del+0x12b4/0x1630 net/ipv6/ip6_fib.c:1996
fib6_clean_node+0x39b/0x570 net/ipv6/ip6_fib.c:2180
fib6_walk_continue+0x4aa/0x8e0 net/ipv6/ip6_fib.c:2102
fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2150
fib6_clean_tree+0xdb/0x120 net/ipv6/ip6_fib.c:2230
__fib6_clean_all+0x120/0x290 net/ipv6/ip6_fib.c:2246
fib6_clean_all net/ipv6/ip6_fib.c:2257 [inline]
fib6_run_gc+0x113/0x2d0 net/ipv6/ip6_fib.c:2320
ndisc_netdev_event+0x217/0x350 net/ipv6/ndisc.c:1805
notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2033
call_netdevice_notifiers_extack net/core/dev.c:2045 [inline]
call_netdevice_notifiers net/core/dev.c:2059 [inline]
dev_close_many+0x30b/0x650 net/core/dev.c:1634
rollback_registered_many+0x3a8/0x1210 net/core/dev.c:9261
rollback_registered net/core/dev.c:9329 [inline]
unregister_netdevice_queue+0x2dd/0x570 net/core/dev.c:10410
unregister_netdevice include/linux/netdevice.h:2774 [inline]
ppp_release+0x216/0x240 drivers/net/ppp/ppp_generic.c:403
__fput+0x285/0x920 fs/file_table.c:281
task_work_run+0xdd/0x190 kernel/task_work.c:141
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:163 [inline]
exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:190
syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 421842e ("net/ipv6: Add fib6_null_entry")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Ido Schimmel says: ==================== net: Fix bridge enslavement failure Patch #1 fixes an issue in which an upper netdev cannot be enslaved to a bridge when it has multiple netdevs with different parent identifiers beneath it. Patch #2 adds a test case using two netdevsim instances. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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When compiling with DEBUG=1 on Fedora 32 I'm getting crash for 'perf test signal': Program received signal SIGSEGV, Segmentation fault. 0x0000000000c68548 in __test_function () (gdb) bt #0 0x0000000000c68548 in __test_function () #1 0x00000000004d62e9 in test_function () at tests/bp_signal.c:61 #2 0x00000000004d689a in test__bp_signal (test=0xa8e280 <generic_ ... #3 0x00000000004b7d49 in run_test (test=0xa8e280 <generic_tests+1 ... #4 0x00000000004b7e7f in test_and_print (t=0xa8e280 <generic_test ... #5 0x00000000004b8927 in __cmd_test (argc=1, argv=0x7fffffffdce0, ... ... It's caused by the symbol __test_function being in the ".bss" section: $ readelf -a ./perf | less [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [28] .bss NOBITS 0000000000c356a0 008346a0 00000000000511f8 0000000000000000 WA 0 0 32 $ nm perf | grep __test_function 0000000000c68548 B __test_function I guess most of the time we're just lucky the inline asm ended up in the ".text" section, so making it specific explicit with push and pop section clauses. $ readelf -a ./perf | less [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [13] .text PROGBITS 0000000000431240 00031240 0000000000306faa 0000000000000000 AX 0 0 16 $ nm perf | grep __test_function 00000000004d62c8 T __test_function Committer testing: $ readelf -wi ~/bin/perf | grep producer -m1 <c> DW_AT_producer : (indirect string, offset: 0x254a): GNU C99 10.2.1 20200723 (Red Hat 10.2.1-1) -mtune=generic -march=x86-64 -ggdb3 -std=gnu99 -fno-omit-frame-pointer -funwind-tables -fstack-protector-all ^^^^^ ^^^^^ ^^^^^ $ Before: $ perf test signal 20: Breakpoint overflow signal handler : FAILED! $ After: $ perf test signal 20: Breakpoint overflow signal handler : Ok $ Fixes: 8fd34e1 ("perf test: Improve bp_signal") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lore.kernel.org/lkml/20200911130005.1842138-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The aliases were never released causing the following leaks:
Indirect leak of 1224 byte(s) in 9 object(s) allocated from:
#0 0x7feefb830628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
#1 0x56332c8f1b62 in __perf_pmu__new_alias util/pmu.c:322
#2 0x56332c8f401f in pmu_add_cpu_aliases_map util/pmu.c:778
#3 0x56332c792ce9 in __test__pmu_event_aliases tests/pmu-events.c:295
#4 0x56332c792ce9 in test_aliases tests/pmu-events.c:367
#5 0x56332c76a09b in run_test tests/builtin-test.c:410
#6 0x56332c76a09b in test_and_print tests/builtin-test.c:440
#7 0x56332c76ce69 in __cmd_test tests/builtin-test.c:695
#8 0x56332c76ce69 in cmd_test tests/builtin-test.c:807
#9 0x56332c7d2214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#10 0x56332c6701a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#11 0x56332c6701a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#12 0x56332c6701a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#13 0x7feefb359cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: 956a783 ("perf test: Test pmu-events aliases")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-11-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The evsel->unit borrows a pointer of pmu event or alias instead of
owns a string. But tool event (duration_time) passes a result of
strdup() caused a leak.
It was found by ASAN during metric test:
Direct leak of 210 byte(s) in 70 object(s) allocated from:
#0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
#1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414
#2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414
#3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
#4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
#5 0x559fbbcc95da in __parse_events util/parse-events.c:2141
#6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406
#7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393
#8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415
#9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498
#10 0x559fbbc0109b in run_test tests/builtin-test.c:410
#11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
#12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
#13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
#14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: f0fbb11 ("perf stat: Implement duration_time as a proper event")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The test_generic_metric() missed to release entries in the pctx. Asan
reported following leak (and more):
Direct leak of 128 byte(s) in 1 object(s) allocated from:
#0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
#1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14)
#2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497)
#3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111
#4 0x55f7e7341667 in expr__add_ref util/expr.c:120
#5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783
#6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858
#7 0x55f7e712390b in compute_single tests/parse-metric.c:128
#8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180
#9 0x55f7e712446d in compute_metric tests/parse-metric.c:196
#10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295
#11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355
#12 0x55f7e70be09b in run_test tests/builtin-test.c:410
#13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
#14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
#15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
#16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: 6d432c4 ("perf tools: Add test_generic_metric function")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The metricgroup__add_metric() can find multiple match for a metric group
and it's possible to fail. Also it can fail in the middle like in
resolve_metric() even for single metric.
In those cases, the intermediate list and ids will be leaked like:
Direct leak of 3 byte(s) in 1 object(s) allocated from:
#0 0x7f4c938f40b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
#1 0x55f7e71c1bef in __add_metric util/metricgroup.c:683
#2 0x55f7e71c31d0 in add_metric util/metricgroup.c:906
#3 0x55f7e71c3844 in metricgroup__add_metric util/metricgroup.c:940
#4 0x55f7e71c488d in metricgroup__add_metric_list util/metricgroup.c:993
#5 0x55f7e71c488d in parse_groups util/metricgroup.c:1045
#6 0x55f7e71c60a4 in metricgroup__parse_groups_test util/metricgroup.c:1087
#7 0x55f7e71235ae in __compute_metric tests/parse-metric.c:164
#8 0x55f7e7124650 in compute_metric tests/parse-metric.c:196
#9 0x55f7e7124650 in test_recursion_fail tests/parse-metric.c:318
#10 0x55f7e7124650 in test__parse_metric tests/parse-metric.c:356
#11 0x55f7e70be09b in run_test tests/builtin-test.c:410
#12 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
#13 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
#14 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
#15 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#16 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#17 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#18 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#19 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: 83de0b7 ("perf metric: Collect referenced metrics in struct metric_ref_node")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The following leaks were detected by ASAN:
Indirect leak of 360 byte(s) in 9 object(s) allocated from:
#0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
#1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333
#2 0x560578f752fc in perf_pmu_parse util/pmu.y:59
#3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73
#4 0x560578e07045 in test__pmu tests/pmu.c:155
#5 0x560578de109b in run_test tests/builtin-test.c:410
#6 0x560578de109b in test_and_print tests/builtin-test.c:440
#7 0x560578de401a in __cmd_test tests/builtin-test.c:661
#8 0x560578de401a in cmd_test tests/builtin-test.c:807
#9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: cff7f95 ("perf tests: Move pmu tests into separate object")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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…kernel/git/kvmarm/kvmarm into kvm-master KVM/arm64 fixes for 5.9, take #2 - Fix handling of S1 Page Table Walk permission fault at S2 on instruction fetch - Cleanup kvm_vcpu_dabt_iswrite()
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syzbot reports a potential lock deadlock between the normal IO path and
->show_fdinfo():
======================================================
WARNING: possible circular locking dependency detected
5.9.0-rc6-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/19710 is trying to acquire lock:
ffff888098ddc450 (sb_writers#4){.+.+}-{0:0}, at: io_write+0x6b5/0xb30 fs/io_uring.c:3296
but task is already holding lock:
ffff8880a11b8428 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_enter+0xe9a/0x1bd0 fs/io_uring.c:8348
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&ctx->uring_lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:956 [inline]
__mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103
__io_uring_show_fdinfo fs/io_uring.c:8417 [inline]
io_uring_show_fdinfo+0x194/0xc70 fs/io_uring.c:8460
seq_show+0x4a8/0x700 fs/proc/fd.c:65
seq_read+0x432/0x1070 fs/seq_file.c:208
do_loop_readv_writev fs/read_write.c:734 [inline]
do_loop_readv_writev fs/read_write.c:721 [inline]
do_iter_read+0x48e/0x6e0 fs/read_write.c:955
vfs_readv+0xe5/0x150 fs/read_write.c:1073
kernel_readv fs/splice.c:355 [inline]
default_file_splice_read.constprop.0+0x4e6/0x9e0 fs/splice.c:412
do_splice_to+0x137/0x170 fs/splice.c:871
splice_direct_to_actor+0x307/0x980 fs/splice.c:950
do_splice_direct+0x1b3/0x280 fs/splice.c:1059
do_sendfile+0x55f/0xd40 fs/read_write.c:1540
__do_sys_sendfile64 fs/read_write.c:1601 [inline]
__se_sys_sendfile64 fs/read_write.c:1587 [inline]
__x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #1 (&p->lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:956 [inline]
__mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103
seq_read+0x61/0x1070 fs/seq_file.c:155
pde_read fs/proc/inode.c:306 [inline]
proc_reg_read+0x221/0x300 fs/proc/inode.c:318
do_loop_readv_writev fs/read_write.c:734 [inline]
do_loop_readv_writev fs/read_write.c:721 [inline]
do_iter_read+0x48e/0x6e0 fs/read_write.c:955
vfs_readv+0xe5/0x150 fs/read_write.c:1073
kernel_readv fs/splice.c:355 [inline]
default_file_splice_read.constprop.0+0x4e6/0x9e0 fs/splice.c:412
do_splice_to+0x137/0x170 fs/splice.c:871
splice_direct_to_actor+0x307/0x980 fs/splice.c:950
do_splice_direct+0x1b3/0x280 fs/splice.c:1059
do_sendfile+0x55f/0xd40 fs/read_write.c:1540
__do_sys_sendfile64 fs/read_write.c:1601 [inline]
__se_sys_sendfile64 fs/read_write.c:1587 [inline]
__x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (sb_writers#4){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:2496 [inline]
check_prevs_add kernel/locking/lockdep.c:2601 [inline]
validate_chain kernel/locking/lockdep.c:3218 [inline]
__lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4441
lock_acquire+0x1f3/0xaf0 kernel/locking/lockdep.c:5029
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write+0x228/0x450 fs/super.c:1672
io_write+0x6b5/0xb30 fs/io_uring.c:3296
io_issue_sqe+0x18f/0x5c50 fs/io_uring.c:5719
__io_queue_sqe+0x280/0x1160 fs/io_uring.c:6175
io_queue_sqe+0x692/0xfa0 fs/io_uring.c:6254
io_submit_sqe fs/io_uring.c:6324 [inline]
io_submit_sqes+0x1761/0x2400 fs/io_uring.c:6521
__do_sys_io_uring_enter+0xeac/0x1bd0 fs/io_uring.c:8349
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
other info that might help us debug this:
Chain exists of:
sb_writers#4 --> &p->lock --> &ctx->uring_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ctx->uring_lock);
lock(&p->lock);
lock(&ctx->uring_lock);
lock(sb_writers#4);
*** DEADLOCK ***
1 lock held by syz-executor.2/19710:
#0: ffff8880a11b8428 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_enter+0xe9a/0x1bd0 fs/io_uring.c:8348
stack backtrace:
CPU: 0 PID: 19710 Comm: syz-executor.2 Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fd lib/dump_stack.c:118
check_noncircular+0x324/0x3e0 kernel/locking/lockdep.c:1827
check_prev_add kernel/locking/lockdep.c:2496 [inline]
check_prevs_add kernel/locking/lockdep.c:2601 [inline]
validate_chain kernel/locking/lockdep.c:3218 [inline]
__lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4441
lock_acquire+0x1f3/0xaf0 kernel/locking/lockdep.c:5029
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write+0x228/0x450 fs/super.c:1672
io_write+0x6b5/0xb30 fs/io_uring.c:3296
io_issue_sqe+0x18f/0x5c50 fs/io_uring.c:5719
__io_queue_sqe+0x280/0x1160 fs/io_uring.c:6175
io_queue_sqe+0x692/0xfa0 fs/io_uring.c:6254
io_submit_sqe fs/io_uring.c:6324 [inline]
io_submit_sqes+0x1761/0x2400 fs/io_uring.c:6521
__do_sys_io_uring_enter+0xeac/0x1bd0 fs/io_uring.c:8349
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e179
Code: 3d b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 0b b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1194e74c78 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: ffffffffffffffda RBX: 00000000000082c0 RCX: 000000000045e179
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000004
RBP: 000000000118cf98 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffd1aa5756f R14: 00007f1194e759c0 R15: 000000000118cf4c
Fix this by just not diving into details if we fail to trylock the
io_uring mutex. We know the ctx isn't going away during this operation,
but we cannot safely iterate buffers/files/personalities if we don't
hold the io_uring mutex.
Reported-by: syzbot+2f8fa4e860edc3066aba@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This patch is to add a new variable 'nested_level' into the net_device
structure.
This variable will be used as a parameter of spin_lock_nested() of
dev->addr_list_lock.
netif_addr_lock() can be called recursively so spin_lock_nested() is
used instead of spin_lock() and dev->lower_level is used as a parameter
of spin_lock_nested().
But, dev->lower_level value can be updated while it is being used.
So, lockdep would warn a possible deadlock scenario.
When a stacked interface is deleted, netif_{uc | mc}_sync() is
called recursively.
So, spin_lock_nested() is called recursively too.
At this moment, the dev->lower_level variable is used as a parameter of it.
dev->lower_level value is updated when interfaces are being unlinked/linked
immediately.
Thus, After unlinking, dev->lower_level shouldn't be a parameter of
spin_lock_nested().
A (macvlan)
|
B (vlan)
|
C (bridge)
|
D (macvlan)
|
E (vlan)
|
F (bridge)
A->lower_level : 6
B->lower_level : 5
C->lower_level : 4
D->lower_level : 3
E->lower_level : 2
F->lower_level : 1
When an interface 'A' is removed, it releases resources.
At this moment, netif_addr_lock() would be called.
Then, netdev_upper_dev_unlink() is called recursively.
Then dev->lower_level is updated.
There is no problem.
But, when the bridge module is removed, 'C' and 'F' interfaces
are removed at once.
If 'F' is removed first, a lower_level value is like below.
A->lower_level : 5
B->lower_level : 4
C->lower_level : 3
D->lower_level : 2
E->lower_level : 1
F->lower_level : 1
Then, 'C' is removed. at this moment, netif_addr_lock() is called
recursively.
The ordering is like this.
C(3)->D(2)->E(1)->F(1)
At this moment, the lower_level value of 'E' and 'F' are the same.
So, lockdep warns a possible deadlock scenario.
In order to avoid this problem, a new variable 'nested_level' is added.
This value is the same as dev->lower_level - 1.
But this value is updated in rtnl_unlock().
So, this variable can be used as a parameter of spin_lock_nested() safely
in the rtnl context.
Test commands:
ip link add br0 type bridge vlan_filtering 1
ip link add vlan1 link br0 type vlan id 10
ip link add macvlan2 link vlan1 type macvlan
ip link add br3 type bridge vlan_filtering 1
ip link set macvlan2 master br3
ip link add vlan4 link br3 type vlan id 10
ip link add macvlan5 link vlan4 type macvlan
ip link add br6 type bridge vlan_filtering 1
ip link set macvlan5 master br6
ip link add vlan7 link br6 type vlan id 10
ip link add macvlan8 link vlan7 type macvlan
ip link set br0 up
ip link set vlan1 up
ip link set macvlan2 up
ip link set br3 up
ip link set vlan4 up
ip link set macvlan5 up
ip link set br6 up
ip link set vlan7 up
ip link set macvlan8 up
modprobe -rv bridge
Splat looks like:
[ 36.057436][ T744] WARNING: possible recursive locking detected
[ 36.058848][ T744] 5.9.0-rc6+ #728 Not tainted
[ 36.059959][ T744] --------------------------------------------
[ 36.061391][ T744] ip/744 is trying to acquire lock:
[ 36.062590][ T744] ffff8c4767509280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_set_rx_mode+0x19/0x30
[ 36.064922][ T744]
[ 36.064922][ T744] but task is already holding lock:
[ 36.066626][ T744] ffff8c4767769280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_uc_add+0x1e/0x60
[ 36.068851][ T744]
[ 36.068851][ T744] other info that might help us debug this:
[ 36.070731][ T744] Possible unsafe locking scenario:
[ 36.070731][ T744]
[ 36.072497][ T744] CPU0
[ 36.073238][ T744] ----
[ 36.074007][ T744] lock(&vlan_netdev_addr_lock_key);
[ 36.075290][ T744] lock(&vlan_netdev_addr_lock_key);
[ 36.076590][ T744]
[ 36.076590][ T744] *** DEADLOCK ***
[ 36.076590][ T744]
[ 36.078515][ T744] May be due to missing lock nesting notation
[ 36.078515][ T744]
[ 36.080491][ T744] 3 locks held by ip/744:
[ 36.081471][ T744] #0: ffffffff98571df0 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x236/0x490
[ 36.083614][ T744] #1: ffff8c4767769280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_uc_add+0x1e/0x60
[ 36.085942][ T744] #2: ffff8c476c8da280 (&bridge_netdev_addr_lock_key/4){+...}-{2:2}, at: dev_uc_sync+0x39/0x80
[ 36.088400][ T744]
[ 36.088400][ T744] stack backtrace:
[ 36.089772][ T744] CPU: 6 PID: 744 Comm: ip Not tainted 5.9.0-rc6+ #728
[ 36.091364][ T744] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 36.093630][ T744] Call Trace:
[ 36.094416][ T744] dump_stack+0x77/0x9b
[ 36.095385][ T744] __lock_acquire+0xbc3/0x1f40
[ 36.096522][ T744] lock_acquire+0xb4/0x3b0
[ 36.097540][ T744] ? dev_set_rx_mode+0x19/0x30
[ 36.098657][ T744] ? rtmsg_ifinfo+0x1f/0x30
[ 36.099711][ T744] ? __dev_notify_flags+0xa5/0xf0
[ 36.100874][ T744] ? rtnl_is_locked+0x11/0x20
[ 36.101967][ T744] ? __dev_set_promiscuity+0x7b/0x1a0
[ 36.103230][ T744] _raw_spin_lock_bh+0x38/0x70
[ 36.104348][ T744] ? dev_set_rx_mode+0x19/0x30
[ 36.105461][ T744] dev_set_rx_mode+0x19/0x30
[ 36.106532][ T744] dev_set_promiscuity+0x36/0x50
[ 36.107692][ T744] __dev_set_promiscuity+0x123/0x1a0
[ 36.108929][ T744] dev_set_promiscuity+0x1e/0x50
[ 36.110093][ T744] br_port_set_promisc+0x1f/0x40 [bridge]
[ 36.111415][ T744] br_manage_promisc+0x8b/0xe0 [bridge]
[ 36.112728][ T744] __dev_set_promiscuity+0x123/0x1a0
[ 36.113967][ T744] ? __hw_addr_sync_one+0x23/0x50
[ 36.115135][ T744] __dev_set_rx_mode+0x68/0x90
[ 36.116249][ T744] dev_uc_sync+0x70/0x80
[ 36.117244][ T744] dev_uc_add+0x50/0x60
[ 36.118223][ T744] macvlan_open+0x18e/0x1f0 [macvlan]
[ 36.119470][ T744] __dev_open+0xd6/0x170
[ 36.120470][ T744] __dev_change_flags+0x181/0x1d0
[ 36.121644][ T744] dev_change_flags+0x23/0x60
[ 36.122741][ T744] do_setlink+0x30a/0x11e0
[ 36.123778][ T744] ? __lock_acquire+0x92c/0x1f40
[ 36.124929][ T744] ? __nla_validate_parse.part.6+0x45/0x8e0
[ 36.126309][ T744] ? __lock_acquire+0x92c/0x1f40
[ 36.127457][ T744] __rtnl_newlink+0x546/0x8e0
[ 36.128560][ T744] ? lock_acquire+0xb4/0x3b0
[ 36.129623][ T744] ? deactivate_slab.isra.85+0x6a1/0x850
[ 36.130946][ T744] ? __lock_acquire+0x92c/0x1f40
[ 36.132102][ T744] ? lock_acquire+0xb4/0x3b0
[ 36.133176][ T744] ? is_bpf_text_address+0x5/0xe0
[ 36.134364][ T744] ? rtnl_newlink+0x2e/0x70
[ 36.135445][ T744] ? rcu_read_lock_sched_held+0x32/0x60
[ 36.136771][ T744] ? kmem_cache_alloc_trace+0x2d8/0x380
[ 36.138070][ T744] ? rtnl_newlink+0x2e/0x70
[ 36.139164][ T744] rtnl_newlink+0x47/0x70
[ ... ]
Fixes: 845e0eb ("net: change addr_list_lock back to static key")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When closing and freeing the source device we could end up doing our final blkdev_put() on the bdev, which will grab the bd_mutex. As such we want to be holding as few locks as possible, so move this call outside of the dev_replace->lock_finishing_cancel_unmount lock. Since we're modifying the fs_devices we need to make sure we're holding the uuid_mutex here, so take that as well. There's a report from syzbot probably hitting one of the cases where the bd_mutex and device_list_mutex are taken in the wrong order, however it's not with device replace, like this patch fixes. As there's no reproducer available so far, we can't verify the fix. https://lore.kernel.org/lkml/000000000000fc04d105afcf86d7@google.com/ dashboard link: https://syzkaller.appspot.com/bug?extid=84a0634dc5d21d488419 WARNING: possible circular locking dependency detected 5.9.0-rc5-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/6878 is trying to acquire lock: ffff88804c17d780 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1804 but task is already holding lock: ffff8880908cfce0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: close_fs_devices.part.0+0x2e/0x800 fs/btrfs/volumes.c:1159 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 btrfs_finish_chunk_alloc+0x281/0xf90 fs/btrfs/volumes.c:5255 btrfs_create_pending_block_groups+0x2f3/0x700 fs/btrfs/block-group.c:2109 __btrfs_end_transaction+0xf5/0x690 fs/btrfs/transaction.c:916 find_free_extent_update_loop fs/btrfs/extent-tree.c:3807 [inline] find_free_extent+0x23b7/0x2e60 fs/btrfs/extent-tree.c:4127 btrfs_reserve_extent+0x166/0x460 fs/btrfs/extent-tree.c:4206 cow_file_range+0x3de/0x9b0 fs/btrfs/inode.c:1063 btrfs_run_delalloc_range+0x2cf/0x1410 fs/btrfs/inode.c:1838 writepage_delalloc+0x150/0x460 fs/btrfs/extent_io.c:3439 __extent_writepage+0x441/0xd00 fs/btrfs/extent_io.c:3653 extent_write_cache_pages.constprop.0+0x69d/0x1040 fs/btrfs/extent_io.c:4249 extent_writepages+0xcd/0x2b0 fs/btrfs/extent_io.c:4370 do_writepages+0xec/0x290 mm/page-writeback.c:2352 __writeback_single_inode+0x125/0x1400 fs/fs-writeback.c:1461 writeback_sb_inodes+0x53d/0xf40 fs/fs-writeback.c:1721 wb_writeback+0x2ad/0xd40 fs/fs-writeback.c:1894 wb_do_writeback fs/fs-writeback.c:2039 [inline] wb_workfn+0x2dc/0x13e0 fs/fs-writeback.c:2080 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 -> #3 (sb_internal#2){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write+0x234/0x470 fs/super.c:1672 sb_start_intwrite include/linux/fs.h:1690 [inline] start_transaction+0xbe7/0x1170 fs/btrfs/transaction.c:624 find_free_extent_update_loop fs/btrfs/extent-tree.c:3789 [inline] find_free_extent+0x25e1/0x2e60 fs/btrfs/extent-tree.c:4127 btrfs_reserve_extent+0x166/0x460 fs/btrfs/extent-tree.c:4206 cow_file_range+0x3de/0x9b0 fs/btrfs/inode.c:1063 btrfs_run_delalloc_range+0x2cf/0x1410 fs/btrfs/inode.c:1838 writepage_delalloc+0x150/0x460 fs/btrfs/extent_io.c:3439 __extent_writepage+0x441/0xd00 fs/btrfs/extent_io.c:3653 extent_write_cache_pages.constprop.0+0x69d/0x1040 fs/btrfs/extent_io.c:4249 extent_writepages+0xcd/0x2b0 fs/btrfs/extent_io.c:4370 do_writepages+0xec/0x290 mm/page-writeback.c:2352 __writeback_single_inode+0x125/0x1400 fs/fs-writeback.c:1461 writeback_sb_inodes+0x53d/0xf40 fs/fs-writeback.c:1721 wb_writeback+0x2ad/0xd40 fs/fs-writeback.c:1894 wb_do_writeback fs/fs-writeback.c:2039 [inline] wb_workfn+0x2dc/0x13e0 fs/fs-writeback.c:2080 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 -> #2 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}: __flush_work+0x60e/0xac0 kernel/workqueue.c:3041 wb_shutdown+0x180/0x220 mm/backing-dev.c:355 bdi_unregister+0x174/0x590 mm/backing-dev.c:872 del_gendisk+0x820/0xa10 block/genhd.c:933 loop_remove drivers/block/loop.c:2192 [inline] loop_control_ioctl drivers/block/loop.c:2291 [inline] loop_control_ioctl+0x3b1/0x480 drivers/block/loop.c:2257 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (loop_ctl_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 lo_open+0x19/0xd0 drivers/block/loop.c:1893 __blkdev_get+0x759/0x1aa0 fs/block_dev.c:1507 blkdev_get fs/block_dev.c:1639 [inline] blkdev_open+0x227/0x300 fs/block_dev.c:1753 do_dentry_open+0x4b9/0x11b0 fs/open.c:817 do_open fs/namei.c:3251 [inline] path_openat+0x1b9a/0x2730 fs/namei.c:3368 do_filp_open+0x17e/0x3c0 fs/namei.c:3395 do_sys_openat2+0x16d/0x420 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_sys_open fs/open.c:1192 [inline] __se_sys_open fs/open.c:1188 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1188 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&bdev->bd_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:2496 [inline] check_prevs_add kernel/locking/lockdep.c:2601 [inline] validate_chain kernel/locking/lockdep.c:3218 [inline] __lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4426 lock_acquire+0x1f3/0xae0 kernel/locking/lockdep.c:5006 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 blkdev_put+0x30/0x520 fs/block_dev.c:1804 btrfs_close_bdev fs/btrfs/volumes.c:1117 [inline] btrfs_close_bdev fs/btrfs/volumes.c:1107 [inline] btrfs_close_one_device fs/btrfs/volumes.c:1133 [inline] close_fs_devices.part.0+0x1a4/0x800 fs/btrfs/volumes.c:1161 close_fs_devices fs/btrfs/volumes.c:1193 [inline] btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1179 close_ctree+0x688/0x6cb fs/btrfs/disk-io.c:4149 generic_shutdown_super+0x144/0x370 fs/super.c:464 kill_anon_super+0x36/0x60 fs/super.c:1108 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2265 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a3/0x530 fs/namespace.c:1118 task_work_run+0xdd/0x190 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:163 [inline] exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:190 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: &bdev->bd_mutex --> sb_internal#2 --> &fs_devs->device_list_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_devs->device_list_mutex); lock(sb_internal#2); lock(&fs_devs->device_list_mutex); lock(&bdev->bd_mutex); *** DEADLOCK *** 3 locks held by syz-executor.0/6878: #0: ffff88809070c0e0 (&type->s_umount_key#70){++++}-{3:3}, at: deactivate_super+0xa5/0xd0 fs/super.c:365 #1: ffffffff8a5b37a8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_close_devices+0x23/0x1f0 fs/btrfs/volumes.c:1178 #2: ffff8880908cfce0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: close_fs_devices.part.0+0x2e/0x800 fs/btrfs/volumes.c:1159 stack backtrace: CPU: 0 PID: 6878 Comm: syz-executor.0 Not tainted 5.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fd lib/dump_stack.c:118 check_noncircular+0x324/0x3e0 kernel/locking/lockdep.c:1827 check_prev_add kernel/locking/lockdep.c:2496 [inline] check_prevs_add kernel/locking/lockdep.c:2601 [inline] validate_chain kernel/locking/lockdep.c:3218 [inline] __lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4426 lock_acquire+0x1f3/0xae0 kernel/locking/lockdep.c:5006 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 blkdev_put+0x30/0x520 fs/block_dev.c:1804 btrfs_close_bdev fs/btrfs/volumes.c:1117 [inline] btrfs_close_bdev fs/btrfs/volumes.c:1107 [inline] btrfs_close_one_device fs/btrfs/volumes.c:1133 [inline] close_fs_devices.part.0+0x1a4/0x800 fs/btrfs/volumes.c:1161 close_fs_devices fs/btrfs/volumes.c:1193 [inline] btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1179 close_ctree+0x688/0x6cb fs/btrfs/disk-io.c:4149 generic_shutdown_super+0x144/0x370 fs/super.c:464 kill_anon_super+0x36/0x60 fs/super.c:1108 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2265 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a3/0x530 fs/namespace.c:1118 task_work_run+0xdd/0x190 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:163 [inline] exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:190 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x460027 RSP: 002b:00007fff59216328 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000076035 RCX: 0000000000460027 RDX: 0000000000403188 RSI: 0000000000000002 RDI: 00007fff592163d0 RBP: 0000000000000333 R08: 0000000000000000 R09: 000000000000000b R10: 0000000000000005 R11: 0000000000000246 R12: 00007fff59217460 R13: 0000000002df2a60 R14: 0000000000000000 R15: 00007fff59217460 Signed-off-by: Josef Bacik <josef@toxicpanda.com> [ add syzbot reference ] Signed-off-by: David Sterba <dsterba@suse.com>
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Ido Schimmel says: ==================== mlxsw: Couple of fixes Patch #1 fixes firmware flashing when CONFIG_MLXSW_CORE=y and CONFIG_MLXFW=m. Patch #2 prevents EMAD transactions from needlessly failing when the system is under heavy load by using exponential backoff. Please consider patch #2 for stable. ==================== Link: https://lore.kernel.org/r/20201117173352.288491-1-idosch@idosch.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Dec 16, 2020
When running test case btrfs/017 from fstests, lockdep reported the following splat: [ 1297.067385] ====================================================== [ 1297.067708] WARNING: possible circular locking dependency detected [ 1297.068022] 5.10.0-rc4-btrfs-next-73 #1 Not tainted [ 1297.068322] ------------------------------------------------------ [ 1297.068629] btrfs/189080 is trying to acquire lock: [ 1297.068929] ffff9f2725731690 (sb_internal#2){.+.+}-{0:0}, at: btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.069274] but task is already holding lock: [ 1297.069868] ffff9f2702b61a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_quota_enable+0x3b/0xa70 [btrfs] [ 1297.070219] which lock already depends on the new lock. [ 1297.071131] the existing dependency chain (in reverse order) is: [ 1297.071721] -> #1 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}: [ 1297.072375] lock_acquire+0xd8/0x490 [ 1297.072710] __mutex_lock+0xa3/0xb30 [ 1297.073061] btrfs_qgroup_inherit+0x59/0x6a0 [btrfs] [ 1297.073421] create_subvol+0x194/0x990 [btrfs] [ 1297.073780] btrfs_mksubvol+0x3fb/0x4a0 [btrfs] [ 1297.074133] __btrfs_ioctl_snap_create+0x119/0x1a0 [btrfs] [ 1297.074498] btrfs_ioctl_snap_create+0x58/0x80 [btrfs] [ 1297.074872] btrfs_ioctl+0x1a90/0x36f0 [btrfs] [ 1297.075245] __x64_sys_ioctl+0x83/0xb0 [ 1297.075617] do_syscall_64+0x33/0x80 [ 1297.075993] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1297.076380] -> #0 (sb_internal#2){.+.+}-{0:0}: [ 1297.077166] check_prev_add+0x91/0xc60 [ 1297.077572] __lock_acquire+0x1740/0x3110 [ 1297.077984] lock_acquire+0xd8/0x490 [ 1297.078411] start_transaction+0x3c5/0x760 [btrfs] [ 1297.078853] btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.079323] btrfs_ioctl+0x2c60/0x36f0 [btrfs] [ 1297.079789] __x64_sys_ioctl+0x83/0xb0 [ 1297.080232] do_syscall_64+0x33/0x80 [ 1297.080680] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1297.081139] other info that might help us debug this: [ 1297.082536] Possible unsafe locking scenario: [ 1297.083510] CPU0 CPU1 [ 1297.084005] ---- ---- [ 1297.084500] lock(&fs_info->qgroup_ioctl_lock); [ 1297.084994] lock(sb_internal#2); [ 1297.085485] lock(&fs_info->qgroup_ioctl_lock); [ 1297.085974] lock(sb_internal#2); [ 1297.086454] *** DEADLOCK *** [ 1297.087880] 3 locks held by btrfs/189080: [ 1297.088324] #0: ffff9f2725731470 (sb_writers#14){.+.+}-{0:0}, at: btrfs_ioctl+0xa73/0x36f0 [btrfs] [ 1297.088799] #1: ffff9f2702b60cc0 (&fs_info->subvol_sem){++++}-{3:3}, at: btrfs_ioctl+0x1f4d/0x36f0 [btrfs] [ 1297.089284] #2: ffff9f2702b61a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_quota_enable+0x3b/0xa70 [btrfs] [ 1297.089771] stack backtrace: [ 1297.090662] CPU: 5 PID: 189080 Comm: btrfs Not tainted 5.10.0-rc4-btrfs-next-73 #1 [ 1297.091132] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 1297.092123] Call Trace: [ 1297.092629] dump_stack+0x8d/0xb5 [ 1297.093115] check_noncircular+0xff/0x110 [ 1297.093596] check_prev_add+0x91/0xc60 [ 1297.094076] ? kvm_clock_read+0x14/0x30 [ 1297.094553] ? kvm_sched_clock_read+0x5/0x10 [ 1297.095029] __lock_acquire+0x1740/0x3110 [ 1297.095510] lock_acquire+0xd8/0x490 [ 1297.095993] ? btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.096476] start_transaction+0x3c5/0x760 [btrfs] [ 1297.096962] ? btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.097451] btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.097941] ? btrfs_ioctl+0x1f4d/0x36f0 [btrfs] [ 1297.098429] btrfs_ioctl+0x2c60/0x36f0 [btrfs] [ 1297.098904] ? do_user_addr_fault+0x20c/0x430 [ 1297.099382] ? kvm_clock_read+0x14/0x30 [ 1297.099854] ? kvm_sched_clock_read+0x5/0x10 [ 1297.100328] ? sched_clock+0x5/0x10 [ 1297.100801] ? sched_clock_cpu+0x12/0x180 [ 1297.101272] ? __x64_sys_ioctl+0x83/0xb0 [ 1297.101739] __x64_sys_ioctl+0x83/0xb0 [ 1297.102207] do_syscall_64+0x33/0x80 [ 1297.102673] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1297.103148] RIP: 0033:0x7f773ff65d87 This is because during the quota enable ioctl we lock first the mutex qgroup_ioctl_lock and then start a transaction, and starting a transaction acquires a fs freeze semaphore (at the VFS level). However, every other code path, except for the quota disable ioctl path, we do the opposite: we start a transaction and then lock the mutex. So fix this by making the quota enable and disable paths to start the transaction without having the mutex locked, and then, after starting the transaction, lock the mutex and check if some other task already enabled or disabled the quotas, bailing with success if that was the case. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux/linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
ojeda
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Drop support for virtualizing adaptive PEBS, as KVM's implementation is architecturally broken without an obvious/easy path forward, and because exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak host kernel addresses to the guest. Bug #1 is that KVM doesn't account for the upper 32 bits of IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters() stores local variables as u8s and truncates the upper bits too, etc. Bug #2 is that, because KVM _always_ sets precise_ip to a non-zero value for PEBS events, perf will _always_ generate an adaptive record, even if the guest requested a basic record. Note, KVM will also enable adaptive PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero, i.e. the guest will only ever see Basic records. Bug #3 is in perf. intel_pmu_disable_fixed() doesn't clear the upper bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE either. I.e. perf _always_ enables ADAPTIVE counters, regardless of what KVM requests. Bug #4 is that adaptive PEBS *might* effectively bypass event filters set by the host, as "Updated Memory Access Info Group" records information that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER. Bug #5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least zeros) when entering a vCPU with adaptive PEBS, which allows the guest to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries" records. Disable adaptive PEBS support as an immediate fix due to the severity of the LBR leak in particular, and because fixing all of the bugs will be non-trivial, e.g. not suitable for backporting to stable kernels. Note! This will break live migration, but trying to make KVM play nice with live migration would be quite complicated, wouldn't be guaranteed to work (i.e. KVM might still kill/confuse the guest), and it's not clear that there are any publicly available VMMs that support adaptive PEBS, let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't support PEBS in any capacity. Link: https://lore.kernel.org/all/20240306230153.786365-1-seanjc@google.com Link: https://lore.kernel.org/all/ZeepGjHCeSfadANM@google.com Fixes: c59a1f1 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS") Cc: stable@vger.kernel.org Cc: Like Xu <like.xu.linux@gmail.com> Cc: Mingwei Zhang <mizhang@google.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhang Xiong <xiong.y.zhang@intel.com> Cc: Lv Zhiyuan <zhiyuan.lv@intel.com> Cc: Dapeng Mi <dapeng1.mi@intel.com> Cc: Jim Mattson <jmattson@google.com> Acked-by: Like Xu <likexu@tencent.com> Link: https://lore.kernel.org/r/20240307005833.827147-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
ojeda
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…"RESET" Set the enable bits for general purpose counters in IA32_PERF_GLOBAL_CTRL when refreshing the PMU to emulate the MSR's architecturally defined post-RESET behavior. Per Intel's SDM: IA32_PERF_GLOBAL_CTRL: Sets bits n-1:0 and clears the upper bits. and Where "n" is the number of general-purpose counters available in the processor. AMD also documents this behavior for PerfMonV2 CPUs in one of AMD's many PPRs. Do not set any PERF_GLOBAL_CTRL bits if there are no general purpose counters, although a literal reading of the SDM would require the CPU to set either bits 63:0 or 31:0. The intent of the behavior is to globally enable all GP counters; honor the intent, if not the letter of the law. Leaving PERF_GLOBAL_CTRL '0' effectively breaks PMU usage in guests that haven't been updated to work with PMUs that support PERF_GLOBAL_CTRL. This bug was recently exposed when KVM added supported for AMD's PerfMonV2, i.e. when KVM started exposing a vPMU with PERF_GLOBAL_CTRL to guest software that only knew how to program v1 PMUs (that don't support PERF_GLOBAL_CTRL). Failure to emulate the post-RESET behavior results in such guests unknowingly leaving all general purpose counters globally disabled (the entire reason the post-RESET value sets the GP counter enable bits is to maintain backwards compatibility). The bug has likely gone unnoticed because PERF_GLOBAL_CTRL has been supported on Intel CPUs for as long as KVM has existed, i.e. hardly anyone is running guest software that isn't aware of PERF_GLOBAL_CTRL on Intel PMUs. And because up until v6.0, KVM _did_ emulate the behavior for Intel CPUs, although the old behavior was likely dumb luck. Because (a) that old code was also broken in its own way (the history of this code is a comedy of errors), and (b) PERF_GLOBAL_CTRL was documented as having a value of '0' post-RESET in all SDMs before March 2023. Initial vPMU support in commit f5132b0 ("KVM: Expose a version 2 architectural PMU to a guests") *almost* got it right (again likely by dumb luck), but for some reason only set the bits if the guest PMU was advertised as v1: if (pmu->version == 1) { pmu->global_ctrl = (1 << pmu->nr_arch_gp_counters) - 1; return; } Commit f19a0c2 ("KVM: PMU emulation: GLOBAL_CTRL MSR should be enabled on reset") then tried to remedy that goof, presumably because guest PMUs were leaving PERF_GLOBAL_CTRL '0', i.e. weren't enabling counters. pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) | (((1ull << pmu->nr_arch_fixed_counters) - 1) << X86_PMC_IDX_FIXED); pmu->global_ctrl_mask = ~pmu->global_ctrl; That was KVM's behavior up until commit c49467a ("KVM: x86/pmu: Don't overwrite the pmu->global_ctrl when refreshing") removed *everything*. However, it did so based on the behavior defined by the SDM , which at the time stated that "Global Perf Counter Controls" is '0' at Power-Up and RESET. But then the March 2023 SDM (325462-079US), stealthily changed its "IA-32 and Intel 64 Processor States Following Power-up, Reset, or INIT" table to say: IA32_PERF_GLOBAL_CTRL: Sets bits n-1:0 and clears the upper bits. Note, kvm_pmu_refresh() can be invoked multiple times, i.e. it's not a "pure" RESET flow. But it can only be called prior to the first KVM_RUN, i.e. the guest will only ever observe the final value. Note #2, KVM has always cleared global_ctrl during refresh (see commit f5132b0 ("KVM: Expose a version 2 architectural PMU to a guests")), i.e. there is no danger of breaking existing setups by clobbering a value set by userspace. Reported-by: Babu Moger <babu.moger@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Like Xu <like.xu.linux@gmail.com> Cc: Mingwei Zhang <mizhang@google.com> Cc: Dapeng Mi <dapeng1.mi@linux.intel.com> Cc: stable@vger.kernel.org Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Link: https://lore.kernel.org/r/20240309013641.1413400-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
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…git/netfilter/nf netfilter pull request 24-04-11 Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patches #1 and #2 add missing rcu read side lock when iterating over expression and object type list which could race with module removal. Patch #3 prevents promisc packet from visiting the bridge/input hook to amend a recent fix to address conntrack confirmation race in br_netfilter and nf_conntrack_bridge. Patch #4 adds and uses iterate decorator type to fetch the current pipapo set backend datastructure view when netlink dumps the set elements. Patch #5 fixes removal of duplicate elements in the pipapo set backend. Patch #6 flowtable validates pppoe header before accessing it. Patch #7 fixes flowtable datapath for pppoe packets, otherwise lookup fails and pppoe packets follow classic path. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
ojeda
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When disabling aRFS under the `priv->state_lock`, any scheduled aRFS works are canceled using the `cancel_work_sync` function, which waits for the work to end if it has already started. However, while waiting for the work handler, the handler will try to acquire the `state_lock` which is already acquired. The worker acquires the lock to delete the rules if the state is down, which is not the worker's responsibility since disabling aRFS deletes the rules. Add an aRFS state variable, which indicates whether the aRFS is enabled and prevent adding rules when the aRFS is disabled. Kernel log: ====================================================== WARNING: possible circular locking dependency detected 6.7.0-rc4_net_next_mlx5_5483eb2 #1 Tainted: G I ------------------------------------------------------ ethtool/386089 is trying to acquire lock: ffff88810f21ce68 ((work_completion)(&rule->arfs_work)){+.+.}-{0:0}, at: __flush_work+0x74/0x4e0 but task is already holding lock: ffff8884a1808cc0 (&priv->state_lock){+.+.}-{3:3}, at: mlx5e_ethtool_set_channels+0x53/0x200 [mlx5_core] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&priv->state_lock){+.+.}-{3:3}: __mutex_lock+0x80/0xc90 arfs_handle_work+0x4b/0x3b0 [mlx5_core] process_one_work+0x1dc/0x4a0 worker_thread+0x1bf/0x3c0 kthread+0xd7/0x100 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x11/0x20 -> #0 ((work_completion)(&rule->arfs_work)){+.+.}-{0:0}: __lock_acquire+0x17b4/0x2c80 lock_acquire+0xd0/0x2b0 __flush_work+0x7a/0x4e0 __cancel_work_timer+0x131/0x1c0 arfs_del_rules+0x143/0x1e0 [mlx5_core] mlx5e_arfs_disable+0x1b/0x30 [mlx5_core] mlx5e_ethtool_set_channels+0xcb/0x200 [mlx5_core] ethnl_set_channels+0x28f/0x3b0 ethnl_default_set_doit+0xec/0x240 genl_family_rcv_msg_doit+0xd0/0x120 genl_rcv_msg+0x188/0x2c0 netlink_rcv_skb+0x54/0x100 genl_rcv+0x24/0x40 netlink_unicast+0x1a1/0x270 netlink_sendmsg+0x214/0x460 __sock_sendmsg+0x38/0x60 __sys_sendto+0x113/0x170 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x40/0xe0 entry_SYSCALL_64_after_hwframe+0x46/0x4e other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->state_lock); lock((work_completion)(&rule->arfs_work)); lock(&priv->state_lock); lock((work_completion)(&rule->arfs_work)); *** DEADLOCK *** 3 locks held by ethtool/386089: #0: ffffffff82ea7210 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 #1: ffffffff82e94c88 (rtnl_mutex){+.+.}-{3:3}, at: ethnl_default_set_doit+0xd3/0x240 #2: ffff8884a1808cc0 (&priv->state_lock){+.+.}-{3:3}, at: mlx5e_ethtool_set_channels+0x53/0x200 [mlx5_core] stack backtrace: CPU: 15 PID: 386089 Comm: ethtool Tainted: G I 6.7.0-rc4_net_next_mlx5_5483eb2 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x60/0xa0 check_noncircular+0x144/0x160 __lock_acquire+0x17b4/0x2c80 lock_acquire+0xd0/0x2b0 ? __flush_work+0x74/0x4e0 ? save_trace+0x3e/0x360 ? __flush_work+0x74/0x4e0 __flush_work+0x7a/0x4e0 ? __flush_work+0x74/0x4e0 ? __lock_acquire+0xa78/0x2c80 ? lock_acquire+0xd0/0x2b0 ? mark_held_locks+0x49/0x70 __cancel_work_timer+0x131/0x1c0 ? mark_held_locks+0x49/0x70 arfs_del_rules+0x143/0x1e0 [mlx5_core] mlx5e_arfs_disable+0x1b/0x30 [mlx5_core] mlx5e_ethtool_set_channels+0xcb/0x200 [mlx5_core] ethnl_set_channels+0x28f/0x3b0 ethnl_default_set_doit+0xec/0x240 genl_family_rcv_msg_doit+0xd0/0x120 genl_rcv_msg+0x188/0x2c0 ? ethnl_ops_begin+0xb0/0xb0 ? genl_family_rcv_msg_dumpit+0xf0/0xf0 netlink_rcv_skb+0x54/0x100 genl_rcv+0x24/0x40 netlink_unicast+0x1a1/0x270 netlink_sendmsg+0x214/0x460 __sock_sendmsg+0x38/0x60 __sys_sendto+0x113/0x170 ? do_user_addr_fault+0x53f/0x8f0 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x40/0xe0 entry_SYSCALL_64_after_hwframe+0x46/0x4e </TASK> Fixes: 45bf454 ("net/mlx5e: Enabling aRFS mechanism") Signed-off-by: Carolina Jubran <cjubran@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Link: https://lore.kernel.org/r/20240411115444.374475-7-tariqt@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ojeda
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Apr 29, 2024
When I did hard offline test with hugetlb pages, below deadlock occurs: ====================================================== WARNING: possible circular locking dependency detected 6.8.0-11409-gf6cef5f8c37f #1 Not tainted ------------------------------------------------------ bash/46904 is trying to acquire lock: ffffffffabe68910 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_slow_dec+0x16/0x60 but task is already holding lock: ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (pcp_batch_high_lock){+.+.}-{3:3}: __mutex_lock+0x6c/0x770 page_alloc_cpu_online+0x3c/0x70 cpuhp_invoke_callback+0x397/0x5f0 __cpuhp_invoke_callback_range+0x71/0xe0 _cpu_up+0xeb/0x210 cpu_up+0x91/0xe0 cpuhp_bringup_mask+0x49/0xb0 bringup_nonboot_cpus+0xb7/0xe0 smp_init+0x25/0xa0 kernel_init_freeable+0x15f/0x3e0 kernel_init+0x15/0x1b0 ret_from_fork+0x2f/0x50 ret_from_fork_asm+0x1a/0x30 -> #0 (cpu_hotplug_lock){++++}-{0:0}: __lock_acquire+0x1298/0x1cd0 lock_acquire+0xc0/0x2b0 cpus_read_lock+0x2a/0xc0 static_key_slow_dec+0x16/0x60 __hugetlb_vmemmap_restore_folio+0x1b9/0x200 dissolve_free_huge_page+0x211/0x260 __page_handle_poison+0x45/0xc0 memory_failure+0x65e/0xc70 hard_offline_page_store+0x55/0xa0 kernfs_fop_write_iter+0x12c/0x1d0 vfs_write+0x387/0x550 ksys_write+0x64/0xe0 do_syscall_64+0xca/0x1e0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pcp_batch_high_lock); lock(cpu_hotplug_lock); lock(pcp_batch_high_lock); rlock(cpu_hotplug_lock); *** DEADLOCK *** 5 locks held by bash/46904: #0: ffff98f6c3bb23f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0 #1: ffff98f6c328e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0 #2: ffff98ef83b31890 (kn->active#113){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0 #3: ffffffffabf9db48 (mf_mutex){+.+.}-{3:3}, at: memory_failure+0x44/0xc70 #4: ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40 stack backtrace: CPU: 10 PID: 46904 Comm: bash Kdump: loaded Not tainted 6.8.0-11409-gf6cef5f8c37f #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x68/0xa0 check_noncircular+0x129/0x140 __lock_acquire+0x1298/0x1cd0 lock_acquire+0xc0/0x2b0 cpus_read_lock+0x2a/0xc0 static_key_slow_dec+0x16/0x60 __hugetlb_vmemmap_restore_folio+0x1b9/0x200 dissolve_free_huge_page+0x211/0x260 __page_handle_poison+0x45/0xc0 memory_failure+0x65e/0xc70 hard_offline_page_store+0x55/0xa0 kernfs_fop_write_iter+0x12c/0x1d0 vfs_write+0x387/0x550 ksys_write+0x64/0xe0 do_syscall_64+0xca/0x1e0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7fc862314887 Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007fff19311268 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007fc862314887 RDX: 000000000000000c RSI: 000056405645fe10 RDI: 0000000000000001 RBP: 000056405645fe10 R08: 00007fc8623d1460 R09: 000000007fffffff R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c R13: 00007fc86241b780 R14: 00007fc862417600 R15: 00007fc862416a00 In short, below scene breaks the lock dependency chain: memory_failure __page_handle_poison zone_pcp_disable -- lock(pcp_batch_high_lock) dissolve_free_huge_page __hugetlb_vmemmap_restore_folio static_key_slow_dec cpus_read_lock -- rlock(cpu_hotplug_lock) Fix this by calling drain_all_pages() instead. This issue won't occur until commit a6b4085 ("mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key"). As it introduced rlock(cpu_hotplug_lock) in dissolve_free_huge_page() code path while lock(pcp_batch_high_lock) is already in the __page_handle_poison(). [linmiaohe@huawei.com: extend comment per Oscar] [akpm@linux-foundation.org: reflow block comment] Link: https://lkml.kernel.org/r/20240407085456.2798193-1-linmiaohe@huawei.com Fixes: a6b4085 ("mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Jane Chu <jane.chu@oracle.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e #3 [fffffe00003fced0] do_nmi at ffffffff8922660d #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 #12 [ffffa65531497b68] printk at ffffffff89318306 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] #18 [ffffa65531497f10] kthread at ffffffff892d2e72 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <lei.chen@smartx.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 amends a missing spot where the set iterator type is unset. This is fixing a issue in the previous pull request. Patch #2 fixes the delete set command abort path by restoring state of the elements. Reverse logic for the activate (abort) case otherwise element state is not restored, this requires to move the check for active/inactive elements to the set iterator callback. From the deactivate path, toggle the next generation bit and from the activate (abort) path, clear the next generation bitmask. Patch #3 skips elements already restored by delete set command from the abort path in case there is a previous delete element command in the batch. Check for the next generation bit just like it is done via set iteration to restore maps. netfilter pull request 24-04-18 * tag 'nf-24-04-18' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nf_tables: fix memleak in map from abort path netfilter: nf_tables: restore set elements when delete set fails netfilter: nf_tables: missing iterator type in lookup walk ==================== Link: https://lore.kernel.org/r/20240418010948.3332346-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Petr Machata says: ==================== mlxsw: Fixes This patchset fixes the following issues: - During driver de-initialization the driver unregisters the EMAD response trap by setting its action to DISCARD. However the manual only permits TRAP and FORWARD, and future firmware versions will enforce this. In patch #1, suppress the error message by aligning the driver to the manual and use a FORWARD (NOP) action when unregistering the trap. - The driver queries the Management Capabilities Mask (MCAM) register during initialization to understand if certain features are supported. However, not all firmware versions support this register, leading to the driver failing to load. Patches #2 and #3 fix this issue by treating an error in the register query as an indication that the feature is not supported. v2: - Patch #2: - Make mlxsw_env_max_module_eeprom_len_query() void ==================== Link: https://lore.kernel.org/r/cover.1713446092.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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… update The rule activity update delayed work periodically traverses the list of configured rules and queries their activity from the device. As part of this task it accesses the entry pointed by 'ventry->entry', but this entry can be changed concurrently by the rehash delayed work, leading to a use-after-free [1]. Fix by closing the race and perform the activity query under the 'vregion->lock' mutex. [1] BUG: KASAN: slab-use-after-free in mlxsw_sp_acl_tcam_flower_rule_activity_get+0x121/0x140 Read of size 8 at addr ffff8881054ed808 by task kworker/0:18/181 CPU: 0 PID: 181 Comm: kworker/0:18 Not tainted 6.9.0-rc2-custom-00781-gd5ab772d32f7 #2 Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019 Workqueue: mlxsw_core mlxsw_sp_acl_rule_activity_update_work Call Trace: <TASK> dump_stack_lvl+0xc6/0x120 print_report+0xce/0x670 kasan_report+0xd7/0x110 mlxsw_sp_acl_tcam_flower_rule_activity_get+0x121/0x140 mlxsw_sp_acl_rule_activity_update_work+0x219/0x400 process_one_work+0x8eb/0x19b0 worker_thread+0x6c9/0xf70 kthread+0x2c9/0x3b0 ret_from_fork+0x4d/0x80 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 1039: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 __kmalloc+0x19c/0x360 mlxsw_sp_acl_tcam_entry_create+0x7b/0x1f0 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x30d/0xb50 mlxsw_sp_acl_tcam_vregion_rehash_work+0x157/0x1300 process_one_work+0x8eb/0x19b0 worker_thread+0x6c9/0xf70 kthread+0x2c9/0x3b0 ret_from_fork+0x4d/0x80 ret_from_fork_asm+0x1a/0x30 Freed by task 1039: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 poison_slab_object+0x102/0x170 __kasan_slab_free+0x14/0x30 kfree+0xc1/0x290 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x3d7/0xb50 mlxsw_sp_acl_tcam_vregion_rehash_work+0x157/0x1300 process_one_work+0x8eb/0x19b0 worker_thread+0x6c9/0xf70 kthread+0x2c9/0x3b0 ret_from_fork+0x4d/0x80 ret_from_fork_asm+0x1a/0x30 Fixes: 2bffc53 ("mlxsw: spectrum_acl: Don't take mutex in mlxsw_sp_acl_tcam_vregion_rehash_work()") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Alexander Zubkov <green@qrator.net> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/1fcce0a60b231ebeb2515d91022284ba7b4ffe7a.1713797103.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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9f74a3d ("ice: Fix VF Reset paths when interface in a failed over aggregate"), the ice driver has acquired the LAG mutex in ice_reset_vf(). The commit placed this lock acquisition just prior to the acquisition of the VF configuration lock. If ice_reset_vf() acquires the configuration lock via the ICE_VF_RESET_LOCK flag, this could deadlock with ice_vc_cfg_qs_msg() because it always acquires the locks in the order of the VF configuration lock and then the LAG mutex. Lockdep reports this violation almost immediately on creating and then removing 2 VF: ====================================================== WARNING: possible circular locking dependency detected 6.8.0-rc6 #54 Tainted: G W O ------------------------------------------------------ kworker/60:3/6771 is trying to acquire lock: ff40d43e099380a0 (&vf->cfg_lock){+.+.}-{3:3}, at: ice_reset_vf+0x22f/0x4d0 [ice] but task is already holding lock: ff40d43ea1961210 (&pf->lag_mutex){+.+.}-{3:3}, at: ice_reset_vf+0xb7/0x4d0 [ice] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&pf->lag_mutex){+.+.}-{3:3}: __lock_acquire+0x4f8/0xb40 lock_acquire+0xd4/0x2d0 __mutex_lock+0x9b/0xbf0 ice_vc_cfg_qs_msg+0x45/0x690 [ice] ice_vc_process_vf_msg+0x4f5/0x870 [ice] __ice_clean_ctrlq+0x2b5/0x600 [ice] ice_service_task+0x2c9/0x480 [ice] process_one_work+0x1e9/0x4d0 worker_thread+0x1e1/0x3d0 kthread+0x104/0x140 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1b/0x30 -> #0 (&vf->cfg_lock){+.+.}-{3:3}: check_prev_add+0xe2/0xc50 validate_chain+0x558/0x800 __lock_acquire+0x4f8/0xb40 lock_acquire+0xd4/0x2d0 __mutex_lock+0x9b/0xbf0 ice_reset_vf+0x22f/0x4d0 [ice] ice_process_vflr_event+0x98/0xd0 [ice] ice_service_task+0x1cc/0x480 [ice] process_one_work+0x1e9/0x4d0 worker_thread+0x1e1/0x3d0 kthread+0x104/0x140 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1b/0x30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pf->lag_mutex); lock(&vf->cfg_lock); lock(&pf->lag_mutex); lock(&vf->cfg_lock); *** DEADLOCK *** 4 locks held by kworker/60:3/6771: #0: ff40d43e05428b38 ((wq_completion)ice){+.+.}-{0:0}, at: process_one_work+0x176/0x4d0 #1: ff50d06e05197e58 ((work_completion)(&pf->serv_task)){+.+.}-{0:0}, at: process_one_work+0x176/0x4d0 #2: ff40d43ea1960e50 (&pf->vfs.table_lock){+.+.}-{3:3}, at: ice_process_vflr_event+0x48/0xd0 [ice] #3: ff40d43ea1961210 (&pf->lag_mutex){+.+.}-{3:3}, at: ice_reset_vf+0xb7/0x4d0 [ice] stack backtrace: CPU: 60 PID: 6771 Comm: kworker/60:3 Tainted: G W O 6.8.0-rc6 #54 Hardware name: Workqueue: ice ice_service_task [ice] Call Trace: <TASK> dump_stack_lvl+0x4a/0x80 check_noncircular+0x12d/0x150 check_prev_add+0xe2/0xc50 ? save_trace+0x59/0x230 ? add_chain_cache+0x109/0x450 validate_chain+0x558/0x800 __lock_acquire+0x4f8/0xb40 ? lockdep_hardirqs_on+0x7d/0x100 lock_acquire+0xd4/0x2d0 ? ice_reset_vf+0x22f/0x4d0 [ice] ? lock_is_held_type+0xc7/0x120 __mutex_lock+0x9b/0xbf0 ? ice_reset_vf+0x22f/0x4d0 [ice] ? ice_reset_vf+0x22f/0x4d0 [ice] ? rcu_is_watching+0x11/0x50 ? ice_reset_vf+0x22f/0x4d0 [ice] ice_reset_vf+0x22f/0x4d0 [ice] ? process_one_work+0x176/0x4d0 ice_process_vflr_event+0x98/0xd0 [ice] ice_service_task+0x1cc/0x480 [ice] process_one_work+0x1e9/0x4d0 worker_thread+0x1e1/0x3d0 ? __pfx_worker_thread+0x10/0x10 kthread+0x104/0x140 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> To avoid deadlock, we must acquire the LAG mutex only after acquiring the VF configuration lock. Fix the ice_reset_vf() to acquire the LAG mutex only after we either acquire or check that the VF configuration lock is held. Fixes: 9f74a3d ("ice: Fix VF Reset paths when interface in a failed over aggregate") Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Dave Ertman <david.m.ertman@intel.com> Reviewed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com> Tested-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> Tested-by: Rafal Romanowski <rafal.romanowski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Link: https://lore.kernel.org/r/20240423182723.740401-5-anthony.l.nguyen@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…nix_gc().
syzbot reported a lockdep splat regarding unix_gc_lock and
unix_state_lock().
One is called from recvmsg() for a connected socket, and another
is called from GC for TCP_LISTEN socket.
So, the splat is false-positive.
Let's add a dedicated lock class for the latter to suppress the splat.
Note that this change is not necessary for net-next.git as the issue
is only applied to the old GC impl.
[0]:
WARNING: possible circular locking dependency detected
6.9.0-rc5-syzkaller-00007-g4d2008430ce8 #0 Not tainted
-----------------------------------------------------
kworker/u8:1/11 is trying to acquire lock:
ffff88807cea4e70 (&u->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff88807cea4e70 (&u->lock){+.+.}-{2:2}, at: __unix_gc+0x40e/0xf70 net/unix/garbage.c:302
but task is already holding lock:
ffffffff8f6ab638 (unix_gc_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffffffff8f6ab638 (unix_gc_lock){+.+.}-{2:2}, at: __unix_gc+0x117/0xf70 net/unix/garbage.c:261
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (unix_gc_lock){+.+.}-{2:2}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
unix_notinflight+0x13d/0x390 net/unix/garbage.c:140
unix_detach_fds net/unix/af_unix.c:1819 [inline]
unix_destruct_scm+0x221/0x350 net/unix/af_unix.c:1876
skb_release_head_state+0x100/0x250 net/core/skbuff.c:1188
skb_release_all net/core/skbuff.c:1200 [inline]
__kfree_skb net/core/skbuff.c:1216 [inline]
kfree_skb_reason+0x16d/0x3b0 net/core/skbuff.c:1252
kfree_skb include/linux/skbuff.h:1262 [inline]
manage_oob net/unix/af_unix.c:2672 [inline]
unix_stream_read_generic+0x1125/0x2700 net/unix/af_unix.c:2749
unix_stream_splice_read+0x239/0x320 net/unix/af_unix.c:2981
do_splice_read fs/splice.c:985 [inline]
splice_file_to_pipe+0x299/0x500 fs/splice.c:1295
do_splice+0xf2d/0x1880 fs/splice.c:1379
__do_splice fs/splice.c:1436 [inline]
__do_sys_splice fs/splice.c:1652 [inline]
__se_sys_splice+0x331/0x4a0 fs/splice.c:1634
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&u->lock){+.+.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
__unix_gc+0x40e/0xf70 net/unix/garbage.c:302
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335
worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(unix_gc_lock);
lock(&u->lock);
lock(unix_gc_lock);
lock(&u->lock);
*** DEADLOCK ***
3 locks held by kworker/u8:1/11:
#0: ffff888015089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline]
#0: ffff888015089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335
#1: ffffc90000107d00 (unix_gc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline]
#1: ffffc90000107d00 (unix_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335
#2: ffffffff8f6ab638 (unix_gc_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffffffff8f6ab638 (unix_gc_lock){+.+.}-{2:2}, at: __unix_gc+0x117/0xf70 net/unix/garbage.c:261
stack backtrace:
CPU: 0 PID: 11 Comm: kworker/u8:1 Not tainted 6.9.0-rc5-syzkaller-00007-g4d2008430ce8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: events_unbound __unix_gc
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
__unix_gc+0x40e/0xf70 net/unix/garbage.c:302
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335
worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Fixes: 47d8ac0 ("af_unix: Fix garbage collector racing against connect()")
Reported-and-tested-by: syzbot+fa379358c28cc87cc307@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=fa379358c28cc87cc307
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240424170443.9832-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ojeda
pushed a commit
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Apr 29, 2024
…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net The following patchset contains two Netfilter/IPVS fixes for net: Patch #1 fixes SCTP checksumming for IPVS with gso packets, from Ismael Luceno. Patch #2 honor dormant flag from netdev event path to fix a possible double hook unregistration. * tag 'nf-24-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nf_tables: honor table dormant flag from netdev release event path ipvs: Fix checksumming on GSO of SCTP packets ==================== Link: https://lore.kernel.org/r/20240425090149.1359547-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
herrnst
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this issue
May 2, 2024
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in Rust 1.75.0, which we were using in the PHYLIB abstractions. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [4] for details. Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could potentially use as an alternative for `ptr_metadata` in the future. For this upgrade, no changes were required (i.e. on our side). The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: rust-lang/rust#91850 [3] Link: Rust-for-Linux/linux#2 [4] Link: rust-lang/rust#96283 [5] Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Tested-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
herrnst
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May 2, 2024
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux/linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
ojeda
added a commit
to ojeda/linux
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May 5, 2024
This is the next upgrade to the Rust toolchain, from 1.77.1 to 1.78.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). It is much smaller than previous upgrades, since the `alloc` fork was dropped in commit 9d0441b ("rust: alloc: remove our fork of the `alloc` crate") [3]. # Unstable features There have been no changes to the set of unstable features used in our own code. Therefore, the only unstable features allowed to be used outside the `kernel` crate is still `new_uninit`. However, since we finally dropped our `alloc` fork [3], all the unstable features used by `alloc` (~30 language ones, ~60 library ones) are not a concern anymore. This reduces the maintenance burden, increases the chances of new compiler versions working without changes and gets us closer to the goal of supporting several compiler versions. It also means that, ignoring non-language/library features, we are currently left with just the few language features needed to implement the kernel `Arc`, the `new_uninit` library feature, the `compiler_builtins` marker and the few `no_*` `cfg`s we pass when compiling `core`/`alloc`. Please see [4] for details. # Required changes ## LLVM's data layout Rust 1.77.0 (i.e. the previous upgrade) introduced a check for matching LLVM data layouts [5]. Then, Rust 1.78.0 upgraded LLVM's bundled major version from 17 to 18 [6], which changed the data layout in x86 [7]. Thus update the data layout in our custom target specification for x86 so that the compiler does not complain about the mismatch: error: data-layout for target `target-5559158138856098584`, `e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128`, differs from LLVM target's `x86_64-linux-gnu` default layout, `e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128` In the future, the goal is to drop the custom target specifications. Meanwhile, if we want to support other LLVM versions used in `rustc` (e.g. for LTO), we will need to add some extra logic (e.g. conditional on LLVM's version, or extracting the data layout from an existing built-in target specification). ## `unused_imports` Rust's `unused_imports` lint covers both unused and redundant imports. Now, in 1.78.0, the lint detects more cases of redundant imports [8]. Thus one of the previous patches cleaned them up. ## Clippy's `new_without_default` Clippy now suggests to implement `Default` even when `new()` is `const`, since `Default::default()` may call `const` functions even if it is not `const` itself [9]. Thus one of the previous patches implemented it. # Other changes in Rust Rust 1.78.0 introduced `feature(asm_goto)` [10] [11]. This feature was discussed in the past [12]. Rust 1.78.0 introduced `feature(const_refs_to_static)` [13] to allow referencing statics in constants and extended `feature(const_mut_refs)` to allow raw mutable pointers in constants. Together, this should cover the kernel's `VTABLE` use case. In fact, the implementation [14] in upstream Rust added a test case for it [15]. Rust 1.78.0 with debug assertions enabled (i.e. `-Cdebug-assertions=y`, kernel's `CONFIG_RUST_DEBUG_ASSERTIONS=y`) now always checks all unsafe preconditions, though without a way to opt-out for particular cases [16]. It would be ideal to have a way to selectively disable certain checks per-call site for this one (i.e. not just per check but for particular instances of a check), even if the vast majority of the checks remain in place [17]. Rust 1.78.0 also improved a couple issues we reported when giving feedback for the new `--check-cfg` feature [18] [19]. # `alloc` upgrade and reviewing As mentioned above, compiler upgrades will not update `alloc` anymore, since we dropped our `alloc` fork [3]. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1780-2024-05-02 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: https://lore.kernel.org/rust-for-linux/20240328013603.206764-1-wedsonaf@gmail.com/ [3] Link: Rust-for-Linux#2 [4] Link: rust-lang/rust#120062 [5] Link: rust-lang/rust#120055 [6] Link: https://reviews.llvm.org/D86310 [7] Link: rust-lang/rust#117772 [8] Link: rust-lang/rust-clippy#10903 [9] Link: rust-lang/rust#119365 [10] Link: rust-lang/rust#119364 [11] Link: https://lore.kernel.org/rust-for-linux/ZWipTZysC2YL7qsq@Boquns-Mac-mini.home/ [12] Link: rust-lang/rust#119618 [13] Link: rust-lang/rust#120932 [14] Link: https://github.com/rust-lang/rust/pull/120932/files#diff-e6fc1622c46054cd46b1d225c5386c5554564b3b0fa8a03c2dc2d8627a1079d9 [15] Link: rust-lang/rust#120969 [16] Link: Rust-for-Linux#354 [17] Link: rust-lang/rust#121202 [18] Link: rust-lang/rust#121237 [19] Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240401212303.537355-4-ojeda@kernel.org [ Added a few more details and links I mentioned in the list. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
asahilina
pushed a commit
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May 10, 2024
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in Rust 1.75.0, which we were using in the PHYLIB abstractions. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [4] for details. Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could potentially use as an alternative for `ptr_metadata` in the future. For this upgrade, no changes were required (i.e. on our side). The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: rust-lang/rust#91850 [3] Link: Rust-for-Linux#2 [4] Link: rust-lang/rust#96283 [5] Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Tested-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
asahilina
pushed a commit
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May 10, 2024
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
jannau
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May 22, 2024
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in Rust 1.75.0, which we were using in the PHYLIB abstractions. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [4] for details. Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could potentially use as an alternative for `ptr_metadata` in the future. For this upgrade, no changes were required (i.e. on our side). The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: rust-lang/rust#91850 [3] Link: Rust-for-Linux#2 [4] Link: rust-lang/rust#96283 [5] Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Tested-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
jannau
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May 22, 2024
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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Pull block updates from Jens Axboe: - Add a partscan attribute in sysfs, fixing an issue with systemd relying on an internal interface that went away. - Attempt #2 at making long running discards interruptible. The previous attempt went into 6.9, but we ended up mostly reverting it as it had issues. - Remove old ida_simple API in bcache - Support for zoned write plugging, greatly improving the performance on zoned devices. - Remove the old throttle low interface, which has been experimental since 2017 and never made it beyond that and isn't being used. - Remove page->index debugging checks in brd, as it hasn't caught anything and prepares us for removing in struct page. - MD pull request from Song - Don't schedule block workers on isolated CPUs * tag 'for-6.10/block-20240511' of git://git.kernel.dk/linux: (84 commits) blk-throttle: delay initialization until configuration blk-throttle: remove CONFIG_BLK_DEV_THROTTLING_LOW block: fix that util can be greater than 100% block: support to account io_ticks precisely block: add plug while submitting IO bcache: fix variable length array abuse in btree_iter bcache: Remove usage of the deprecated ida_simple_xx() API md: Revert "md: Fix overflow in is_mddev_idle" blk-lib: check for kill signal in ioctl BLKDISCARD block: add a bio_await_chain helper block: add a blk_alloc_discard_bio helper block: add a bio_chain_and_submit helper block: move discard checks into the ioctl handler block: remove the discard_granularity check in __blkdev_issue_discard block/ioctl: prefer different overflow check null_blk: Fix the WARNING: modpost: missing MODULE_DESCRIPTION() block: fix and simplify blkdevparts= cmdline parsing block: refine the EOF check in blkdev_iomap_begin block: add a partscan sysfs attribute for disks block: add a disk_has_partscan helper ...
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…rnel/git/netfilter/nf-next Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next: Patch #1 skips transaction if object type provides no .update interface. Patch #2 skips NETDEV_CHANGENAME which is unused. Patch #3 enables conntrack to handle Multicast Router Advertisements and Multicast Router Solicitations from the Multicast Router Discovery protocol (RFC4286) as untracked opposed to invalid packets. From Linus Luessing. Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of dropping them, from Jason Xing. Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0, also from Jason. Patch #6 removes reference in netfilter's sysctl documentation on pickup entries which were already removed by Florian Westphal. Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which allows to evict entries from the conntrack table, also from Florian. Patches #8 to #16 updates nf_tables pipapo set backend to allocate the datastructure copy on-demand from preparation phase, to better deal with OOM situations where .commit step is too late to fail. Series from Florian Westphal. Patch #17 adds a selftest with packetdrill to cover conntrack TCP state transitions, also from Florian. Patch #18 use GFP_KERNEL to clone elements from control plane to avoid quick atomic reserves exhaustion with large sets, reporter refers to million entries magnitude. * tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next: netfilter: nf_tables: allow clone callbacks to sleep selftests: netfilter: add packetdrill based conntrack tests netfilter: nft_set_pipapo: remove dirty flag netfilter: nft_set_pipapo: move cloning of match info to insert/removal path netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone netfilter: nft_set_pipapo: merge deactivate helper into caller netfilter: nft_set_pipapo: prepare walk function for on-demand clone netfilter: nft_set_pipapo: prepare destroy function for on-demand clone netfilter: nft_set_pipapo: make pipapo_clone helper return NULL netfilter: nft_set_pipapo: move prove_locking helper around netfilter: conntrack: remove flowtable early-drop test netfilter: conntrack: documentation: remove reference to non-existent sysctl netfilter: use NF_DROP instead of -NF_DROP netfilter: conntrack: dccp: try not to drop skb in conntrack netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler netfilter: nf_tables: skip transaction if update object is not implemented ==================== Link: https://lore.kernel.org/r/20240512161436.168973-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Xuan Zhuo says:
====================
virtio_net: rx enable premapped mode by default
Actually, for the virtio drivers, we can enable premapped mode whatever
the value of use_dma_api. Because we provide the virtio dma apis.
So the driver can enable premapped mode unconditionally.
This patch set makes the big mode of virtio-net to support premapped mode.
And enable premapped mode for rx by default.
Based on the following points, we do not use page pool to manage these
pages:
1. virtio-net uses the DMA APIs wrapped by virtio core. Therefore,
we can only prevent the page pool from performing DMA operations, and
let the driver perform DMA operations on the allocated pages.
2. But when the page pool releases the page, we have no chance to
execute dma unmap.
3. A solution to #2 is to execute dma unmap every time before putting
the page back to the page pool. (This is actually a waste, we don't
execute unmap so frequently.)
4. But there is another problem, we still need to use page.dma_addr to
save the dma address. Using page.dma_addr while using page pool is
unsafe behavior.
5. And we need space the chain the pages submitted once to virtio core.
More:
https://lore.kernel.org/all/CACGkMEu=Aok9z2imB_c5qVuujSh=vjj1kx12fy9N7hqyi+M5Ow@mail.gmail.com/
Why we do not use the page space to store the dma?
http://lore.kernel.org/all/CACGkMEuyeJ9mMgYnnB42=hw6umNuo=agn7VBqBqYPd7GN=+39Q@mail.gmail.com
====================
Link: https://lore.kernel.org/r/20240511031404.30903-1-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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In dctcp_update_alpha(), we use a module parameter dctcp_shift_g
as follows:
alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g);
...
delivered_ce <<= (10 - dctcp_shift_g);
It seems syzkaller started fuzzing module parameters and triggered
shift-out-of-bounds [0] by setting 100 to dctcp_shift_g:
memcpy((void*)0x20000080,
"/sys/module/tcp_dctcp/parameters/dctcp_shift_g\000", 47);
res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000080ul,
/*flags=*/2ul, /*mode=*/0ul);
memcpy((void*)0x20000000, "100\000", 4);
syscall(__NR_write, /*fd=*/r[0], /*val=*/0x20000000ul, /*len=*/4ul);
Let's limit the max value of dctcp_shift_g by param_set_uint_minmax().
With this patch:
# echo 10 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g
# cat /sys/module/tcp_dctcp/parameters/dctcp_shift_g
10
# echo 11 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g
-bash: echo: write error: Invalid argument
[0]:
UBSAN: shift-out-of-bounds in net/ipv4/tcp_dctcp.c:143:12
shift exponent 100 is too large for 32-bit type 'u32' (aka 'unsigned int')
CPU: 0 PID: 8083 Comm: syz-executor345 Not tainted 6.9.0-05151-g1b294a1f3561 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x201/0x300 lib/dump_stack.c:114
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_shift_out_of_bounds+0x346/0x3a0 lib/ubsan.c:468
dctcp_update_alpha+0x540/0x570 net/ipv4/tcp_dctcp.c:143
tcp_in_ack_event net/ipv4/tcp_input.c:3802 [inline]
tcp_ack+0x17b1/0x3bc0 net/ipv4/tcp_input.c:3948
tcp_rcv_state_process+0x57a/0x2290 net/ipv4/tcp_input.c:6711
tcp_v4_do_rcv+0x764/0xc40 net/ipv4/tcp_ipv4.c:1937
sk_backlog_rcv include/net/sock.h:1106 [inline]
__release_sock+0x20f/0x350 net/core/sock.c:2983
release_sock+0x61/0x1f0 net/core/sock.c:3549
mptcp_subflow_shutdown+0x3d0/0x620 net/mptcp/protocol.c:2907
mptcp_check_send_data_fin+0x225/0x410 net/mptcp/protocol.c:2976
__mptcp_close+0x238/0xad0 net/mptcp/protocol.c:3072
mptcp_close+0x2a/0x1a0 net/mptcp/protocol.c:3127
inet_release+0x190/0x1f0 net/ipv4/af_inet.c:437
__sock_release net/socket.c:659 [inline]
sock_close+0xc0/0x240 net/socket.c:1421
__fput+0x41b/0x890 fs/file_table.c:422
task_work_run+0x23b/0x300 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0x9c8/0x2540 kernel/exit.c:878
do_group_exit+0x201/0x2b0 kernel/exit.c:1027
__do_sys_exit_group kernel/exit.c:1038 [inline]
__se_sys_exit_group kernel/exit.c:1036 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xe4/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x67/0x6f
RIP: 0033:0x7f6c2b5005b6
Code: Unable to access opcode bytes at 0x7f6c2b50058c.
RSP: 002b:00007ffe883eb948 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f6c2b5862f0 RCX: 00007f6c2b5005b6
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
RBP: 0000000000000001 R08: 00000000000000e7 R09: ffffffffffffffc0
R10: 0000000000000006 R11: 0000000000000246 R12: 00007f6c2b5862f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
</TASK>
Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: Yue Sun <samsun1006219@gmail.com>
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/netdev/CAEkJfYNJM=cw-8x7_Vmj1J6uYVCWMbbvD=EFmDPVBGpTsqOxEA@mail.gmail.com/
Fixes: e3118e8 ("net: tcp: add DCTCP congestion control algorithm")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240517091626.32772-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Patch series "Introduce mseal", v10.
This patchset proposes a new mseal() syscall for the Linux kernel.
In a nutshell, mseal() protects the VMAs of a given virtual memory range
against modifications, such as changes to their permission bits.
Modern CPUs support memory permissions, such as the read/write (RW) and
no-execute (NX) bits. Linux has supported NX since the release of kernel
version 2.6.8 in August 2004 [1]. The memory permission feature improves
the security stance on memory corruption bugs, as an attacker cannot
simply write to arbitrary memory and point the code to it. The memory
must be marked with the X bit, or else an exception will occur.
Internally, the kernel maintains the memory permissions in a data
structure called VMA (vm_area_struct). mseal() additionally protects the
VMA itself against modifications of the selected seal type.
Memory sealing is useful to mitigate memory corruption issues where a
corrupted pointer is passed to a memory management system. For example,
such an attacker primitive can break control-flow integrity guarantees
since read-only memory that is supposed to be trusted can become writable
or .text pages can get remapped. Memory sealing can automatically be
applied by the runtime loader to seal .text and .rodata pages and
applications can additionally seal security critical data at runtime. A
similar feature already exists in the XNU kernel with the
VM_FLAGS_PERMANENT [3] flag and on OpenBSD with the mimmutable syscall
[4]. Also, Chrome wants to adopt this feature for their CFI work [2] and
this patchset has been designed to be compatible with the Chrome use case.
Two system calls are involved in sealing the map: mmap() and mseal().
The new mseal() is an syscall on 64 bit CPU, and with following signature:
int mseal(void addr, size_t len, unsigned long flags)
addr/len: memory range.
flags: reserved.
mseal() blocks following operations for the given memory range.
1> Unmapping, moving to another location, and shrinking the size,
via munmap() and mremap(), can leave an empty space, therefore can
be replaced with a VMA with a new set of attributes.
2> Moving or expanding a different VMA into the current location,
via mremap().
3> Modifying a VMA via mmap(MAP_FIXED).
4> Size expansion, via mremap(), does not appear to pose any specific
risks to sealed VMAs. It is included anyway because the use case is
unclear. In any case, users can rely on merging to expand a sealed VMA.
5> mprotect() and pkey_mprotect().
6> Some destructive madvice() behaviors (e.g. MADV_DONTNEED) for anonymous
memory, when users don't have write permission to the memory. Those
behaviors can alter region contents by discarding pages, effectively a
memset(0) for anonymous memory.
The idea that inspired this patch comes from Stephen Röttger’s work in
V8 CFI [5]. Chrome browser in ChromeOS will be the first user of this
API.
Indeed, the Chrome browser has very specific requirements for sealing,
which are distinct from those of most applications. For example, in the
case of libc, sealing is only applied to read-only (RO) or read-execute
(RX) memory segments (such as .text and .RELRO) to prevent them from
becoming writable, the lifetime of those mappings are tied to the lifetime
of the process.
Chrome wants to seal two large address space reservations that are managed
by different allocators. The memory is mapped RW- and RWX respectively
but write access to it is restricted using pkeys (or in the future ARM
permission overlay extensions). The lifetime of those mappings are not
tied to the lifetime of the process, therefore, while the memory is
sealed, the allocators still need to free or discard the unused memory.
For example, with madvise(DONTNEED).
However, always allowing madvise(DONTNEED) on this range poses a security
risk. For example if a jump instruction crosses a page boundary and the
second page gets discarded, it will overwrite the target bytes with zeros
and change the control flow. Checking write-permission before the discard
operation allows us to control when the operation is valid. In this case,
the madvise will only succeed if the executing thread has PKEY write
permissions and PKRU changes are protected in software by control-flow
integrity.
Although the initial version of this patch series is targeting the Chrome
browser as its first user, it became evident during upstream discussions
that we would also want to ensure that the patch set eventually is a
complete solution for memory sealing and compatible with other use cases.
The specific scenario currently in mind is glibc's use case of loading and
sealing ELF executables. To this end, Stephen is working on a change to
glibc to add sealing support to the dynamic linker, which will seal all
non-writable segments at startup. Once this work is completed, all
applications will be able to automatically benefit from these new
protections.
In closing, I would like to formally acknowledge the valuable
contributions received during the RFC process, which were instrumental in
shaping this patch:
Jann Horn: raising awareness and providing valuable insights on the
destructive madvise operations.
Liam R. Howlett: perf optimization.
Linus Torvalds: assisting in defining system call signature and scope.
Theo de Raadt: sharing the experiences and insight gained from
implementing mimmutable() in OpenBSD.
MM perf benchmarks
==================
This patch adds a loop in the mprotect/munmap/madvise(DONTNEED) to
check the VMAs’ sealing flag, so that no partial update can be made,
when any segment within the given memory range is sealed.
To measure the performance impact of this loop, two tests are developed.
[8]
The first is measuring the time taken for a particular system call,
by using clock_gettime(CLOCK_MONOTONIC). The second is using
PERF_COUNT_HW_REF_CPU_CYCLES (exclude user space). Both tests have
similar results.
The tests have roughly below sequence:
for (i = 0; i < 1000, i++)
create 1000 mappings (1 page per VMA)
start the sampling
for (j = 0; j < 1000, j++)
mprotect one mapping
stop and save the sample
delete 1000 mappings
calculates all samples.
Below tests are performed on Intel(R) Pentium(R) Gold 7505 @ 2.00GHz,
4G memory, Chromebook.
Based on the latest upstream code:
The first test (measuring time)
syscall__ vmas t t_mseal delta_ns per_vma %
munmap__ 1 909 944 35 35 104%
munmap__ 2 1398 1502 104 52 107%
munmap__ 4 2444 2594 149 37 106%
munmap__ 8 4029 4323 293 37 107%
munmap__ 16 6647 6935 288 18 104%
munmap__ 32 11811 12398 587 18 105%
mprotect 1 439 465 26 26 106%
mprotect 2 1659 1745 86 43 105%
mprotect 4 3747 3889 142 36 104%
mprotect 8 6755 6969 215 27 103%
mprotect 16 13748 14144 396 25 103%
mprotect 32 27827 28969 1142 36 104%
madvise_ 1 240 262 22 22 109%
madvise_ 2 366 442 76 38 121%
madvise_ 4 623 751 128 32 121%
madvise_ 8 1110 1324 215 27 119%
madvise_ 16 2127 2451 324 20 115%
madvise_ 32 4109 4642 534 17 113%
The second test (measuring cpu cycle)
syscall__ vmas cpu cmseal delta_cpu per_vma %
munmap__ 1 1790 1890 100 100 106%
munmap__ 2 2819 3033 214 107 108%
munmap__ 4 4959 5271 312 78 106%
munmap__ 8 8262 8745 483 60 106%
munmap__ 16 13099 14116 1017 64 108%
munmap__ 32 23221 24785 1565 49 107%
mprotect 1 906 967 62 62 107%
mprotect 2 3019 3203 184 92 106%
mprotect 4 6149 6569 420 105 107%
mprotect 8 9978 10524 545 68 105%
mprotect 16 20448 21427 979 61 105%
mprotect 32 40972 42935 1963 61 105%
madvise_ 1 434 497 63 63 115%
madvise_ 2 752 899 147 74 120%
madvise_ 4 1313 1513 200 50 115%
madvise_ 8 2271 2627 356 44 116%
madvise_ 16 4312 4883 571 36 113%
madvise_ 32 8376 9319 943 29 111%
Based on the result, for 6.8 kernel, sealing check adds
20-40 nano seconds, or around 50-100 CPU cycles, per VMA.
In addition, I applied the sealing to 5.10 kernel:
The first test (measuring time)
syscall__ vmas t tmseal delta_ns per_vma %
munmap__ 1 357 390 33 33 109%
munmap__ 2 442 463 21 11 105%
munmap__ 4 614 634 20 5 103%
munmap__ 8 1017 1137 120 15 112%
munmap__ 16 1889 2153 263 16 114%
munmap__ 32 4109 4088 -21 -1 99%
mprotect 1 235 227 -7 -7 97%
mprotect 2 495 464 -30 -15 94%
mprotect 4 741 764 24 6 103%
mprotect 8 1434 1437 2 0 100%
mprotect 16 2958 2991 33 2 101%
mprotect 32 6431 6608 177 6 103%
madvise_ 1 191 208 16 16 109%
madvise_ 2 300 324 24 12 108%
madvise_ 4 450 473 23 6 105%
madvise_ 8 753 806 53 7 107%
madvise_ 16 1467 1592 125 8 108%
madvise_ 32 2795 3405 610 19 122%
The second test (measuring cpu cycle)
syscall__ nbr_vma cpu cmseal delta_cpu per_vma %
munmap__ 1 684 715 31 31 105%
munmap__ 2 861 898 38 19 104%
munmap__ 4 1183 1235 51 13 104%
munmap__ 8 1999 2045 46 6 102%
munmap__ 16 3839 3816 -23 -1 99%
munmap__ 32 7672 7887 216 7 103%
mprotect 1 397 443 46 46 112%
mprotect 2 738 788 50 25 107%
mprotect 4 1221 1256 35 9 103%
mprotect 8 2356 2429 72 9 103%
mprotect 16 4961 4935 -26 -2 99%
mprotect 32 9882 10172 291 9 103%
madvise_ 1 351 380 29 29 108%
madvise_ 2 565 615 49 25 109%
madvise_ 4 872 933 61 15 107%
madvise_ 8 1508 1640 132 16 109%
madvise_ 16 3078 3323 245 15 108%
madvise_ 32 5893 6704 811 25 114%
For 5.10 kernel, sealing check adds 0-15 ns in time, or 10-30
CPU cycles, there is even decrease in some cases.
It might be interesting to compare 5.10 and 6.8 kernel
The first test (measuring time)
syscall__ vmas t_5_10 t_6_8 delta_ns per_vma %
munmap__ 1 357 909 552 552 254%
munmap__ 2 442 1398 956 478 316%
munmap__ 4 614 2444 1830 458 398%
munmap__ 8 1017 4029 3012 377 396%
munmap__ 16 1889 6647 4758 297 352%
munmap__ 32 4109 11811 7702 241 287%
mprotect 1 235 439 204 204 187%
mprotect 2 495 1659 1164 582 335%
mprotect 4 741 3747 3006 752 506%
mprotect 8 1434 6755 5320 665 471%
mprotect 16 2958 13748 10790 674 465%
mprotect 32 6431 27827 21397 669 433%
madvise_ 1 191 240 49 49 125%
madvise_ 2 300 366 67 33 122%
madvise_ 4 450 623 173 43 138%
madvise_ 8 753 1110 357 45 147%
madvise_ 16 1467 2127 660 41 145%
madvise_ 32 2795 4109 1314 41 147%
The second test (measuring cpu cycle)
syscall__ vmas cpu_5_10 c_6_8 delta_cpu per_vma %
munmap__ 1 684 1790 1106 1106 262%
munmap__ 2 861 2819 1958 979 327%
munmap__ 4 1183 4959 3776 944 419%
munmap__ 8 1999 8262 6263 783 413%
munmap__ 16 3839 13099 9260 579 341%
munmap__ 32 7672 23221 15549 486 303%
mprotect 1 397 906 509 509 228%
mprotect 2 738 3019 2281 1140 409%
mprotect 4 1221 6149 4929 1232 504%
mprotect 8 2356 9978 7622 953 423%
mprotect 16 4961 20448 15487 968 412%
mprotect 32 9882 40972 31091 972 415%
madvise_ 1 351 434 82 82 123%
madvise_ 2 565 752 186 93 133%
madvise_ 4 872 1313 442 110 151%
madvise_ 8 1508 2271 763 95 151%
madvise_ 16 3078 4312 1234 77 140%
madvise_ 32 5893 8376 2483 78 142%
From 5.10 to 6.8
munmap: added 250-550 ns in time, or 500-1100 in cpu cycle, per vma.
mprotect: added 200-750 ns in time, or 500-1200 in cpu cycle, per vma.
madvise: added 33-50 ns in time, or 70-110 in cpu cycle, per vma.
In comparison to mseal, which adds 20-40 ns or 50-100 CPU cycles, the
increase from 5.10 to 6.8 is significantly larger, approximately ten times
greater for munmap and mprotect.
When I discuss the mm performance with Brian Makin, an engineer who worked
on performance, it was brought to my attention that such performance
benchmarks, which measuring millions of mm syscall in a tight loop, may
not accurately reflect real-world scenarios, such as that of a database
service. Also this is tested using a single HW and ChromeOS, the data
from another HW or distribution might be different. It might be best to
take this data with a grain of salt.
This patch (of 5):
Wire up mseal syscall for all architectures.
Link: https://lkml.kernel.org/r/20240415163527.626541-1-jeffxu@chromium.org
Link: https://lkml.kernel.org/r/20240415163527.626541-2-jeffxu@chromium.org
Signed-off-by: Jeff Xu <jeffxu@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Jann Horn <jannh@google.com> [Bug #2]
Cc: Jeff Xu <jeffxu@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jorge Lucangeli Obes <jorgelo@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Cc: Stephen Röttger <sroettger@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Amer Al Shanawany <amer.shanawany@gmail.com>
Cc: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in Rust 1.75.0, which we were using in the PHYLIB abstractions. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [4] for details. Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could potentially use as an alternative for `ptr_metadata` in the future. For this upgrade, no changes were required (i.e. on our side). The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: rust-lang/rust#91850 [3] Link: Rust-for-Linux/linux#2 [4] Link: rust-lang/rust#96283 [5] Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Tested-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux/linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
herrnst
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May 30, 2024
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in Rust 1.75.0, which we were using in the PHYLIB abstractions. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [4] for details. Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could potentially use as an alternative for `ptr_metadata` in the future. For this upgrade, no changes were required (i.e. on our side). The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: rust-lang/rust#91850 [3] Link: Rust-for-Linux/linux#2 [4] Link: rust-lang/rust#96283 [5] Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Tested-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
herrnst
pushed a commit
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May 30, 2024
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux/linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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Unstable features (including language, library, tools...) we currently use.
See as well:
corewanted features & bugfixes #514allocwanted features & bugfixes #408stdwanted features & bugfixes #572rustcwanted features & bugfixes #355rustdocwanted features & bugfixes #350rustfmtwanted features & bugfixes #398bindgenwanted features & bugfixes #353rustupwanted features & bugfixes #396Required (we almost certainly want them)
cfg(no_fp_fmt_parse).core).cfg(no_global_oom_handling).alloc).cfg(no_rc).alloc).alloc: add unstable cfg featuresno_rcandno_syncrust-lang/rust#89891).cfg(no_sync).alloc).alloc: add unstable cfg featuresno_rcandno_syncrust-lang/rust#89891).feature(asm_goto).asm!rust-lang/rust#119365).feature(const_mut_refs)&feature(const_refs_to_static).&mut Tin const contexts (const_mut_refs) rust-lang/rust#57349 and Tracking Issue for const_refs_to_static rust-lang/rust#119618.const TABLEs (settingownerfield toTHIS_MODULE), as well asrust/kernel/module_param.rs(in therustbranch).const_fn.VTABLEtest case (tests/ui/consts/const-ref-to-static-linux-vtable.rs): const_mut_refs: allow mutable pointers to statics rust-lang/rust#120932 (1.78).feature(derive_smart_pointer)(i.e.derive(SmartPointer)).derive(SmartPointer)rust-lang/rust#123430.Arc.derive(SmartPointer)rust-lang/rust#123472.Arc.feature(doc_cfg).#[doc(cfg(…))],#[doc(cfg_hide(…))]anddoc_auto_cfgrust-lang/rust#43781.rust/kernel/lib.rs.doc(cfg(...))from thecfg(...)(to avoid duplication) etc. See also Consider allowing to build docs for the current kernel config #447.feature(impl_trait_in_assoc_type).rnull(https://lore.kernel.org/rust-for-linux/20240313110515.70088-5-nmi@metaspace.dk/).feature(offset_of_nested).offset_of) got stabilized (Stabilize single-field offset_of rust-lang/rust#118799).feature(register_tool).#![register_tool]rust-lang/rust#66079.klintExperimental PR for introducing klint #958.__rust_no_alloc_shim_is_unstable.rust/kernel/allocator.rs.-Zbinary_dep_depinfo=y.-Zbranch-protection.-Z branch-protectionrust-lang/rust#113369.CONFIG_ARM64_BTI_KERNELetc.-Zcf-protection-- see https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/.60-Zbranch-protection.60.20stability/near/391152508.-Zcf-protection=branch(CET).CONFIG_X86_KERNEL_IBT(https://lore.kernel.org/rust-for-linux/20231009224347.2076221-1-mmaurer@google.com/).-Zdebuginfo-compression.-Zdebuginfo-compressionrust-lang/rust#120953.-Zdwarf-version.-Zfixed-x18.-Zfixed-x18rust-lang/rust#124655.-Zfunction-return=thunk-extern.rustcrust-lang/rust#116853.CONFIG_RETHUNK.-Zfunction-return={keep,thunk-extern}option rust-lang/rust#116892.-Zinstrument-mcount.#[coverage]rust-lang/rust#84605 (#[no_coverage]).-Zno-jump-tables.no-jump-tablesrust-lang/rust#116592.CONFIG_X86_KERNEL_IBT(https://lore.kernel.org/rust-for-linux/20231009224347.2076221-1-mmaurer@google.com/).-Zno-jump-tablesrust-lang/rust#105812 (1.68).-Zrandomize-layout(and-Zlayout-seed=<seed>).-Z randomize-layoutrust-lang/rust#106764.CONFIG_RANDSTRUCT*).-Zsanitizer=kcfi&-Zsanitizer-cfi-normalize-integers(KCFI).CONFIG_CFI_CLANG).-Cpanic=abortuntil LLVM'sinvokesupports KCFI bundles: CFI: Abstract Closures and Coroutines rust-lang/rust#123106 (comment).-Ztune-cpu=generic.Makefile.-Zub-checks(cfg(ub_checks)).feature(ub_checks)and-Zub-checksrust-lang/rust#123499.rustdoc's--no-run(-Zunstable-options).--no-runrust-lang/rust#87022.rustdoc's--test-builder(-Zunstable-options).--test-builderrust-lang/rust#102981.Remaining target features unknown to
rustc.#[target_feature]rust-lang/rust#44839.Target specification file or enough command-line flags to replace it.
-Cglobal-target-feature=) could be useful, i.e. a target feature that is required to be set the same way for all compilation units (without requiring a new target). In other words, using flags to create combinations of targets instead of requiring a different for each combination. See-Cfixed-x18discussion as well.Good to have (we could workaround if needed)
--extern force:.--extern forcerust-lang/rust#111302.allocextern to allow "empty" Rust files")).new_uninitis dropped (and there could be other workarounds); added as unstable in 1.71 (Addforceoption for--externflag rust-lang/rust#109421).feature(associated_type_defaults).file_operations.rsto simplify boilerplate needed by drivers, as well aspci.rs(e.g. https://lore.kernel.org/rust-for-linux/20240520172554.182094-10-dakr@redhat.com/).feature(const_refs_to_cell).const_refs_to_cellrust-lang/rust#80384.rust/kernel/driver.rs,offset_of!(iffeature(offset_of)does not pan out).const_heap.feature(const_trait_impl).impl const Trait for Tyand~const(tilde const) syntax rust-lang/rust#67792.rust/kernel/driver.rs(e.g. see_new_id_array!,define_id_array!anddefine_id_table!in https://lore.kernel.org/rust-for-linux/20240520172554.182094-3-dakr@redhat.com/).feature(c_size_t)# rust-lang/rust#88345.rust/kernel/file.rs(so far, but could be anywhere in the abstractions).core_ffi_cgot stabilized in 1.64 (Stabilizecore::ffi:c_*and re-export instd::ffirust-lang/rust#98315) andc_{s,}size_tare now incore::ffisince 1.61 (Provide C FFI types via core::ffi, not just in std rust-lang/rust#94503). We can always go back toc_types.rs.feature(duration_constants).rust/kernel/delay.rs.TimeUnitsto do things like2.seconds()). We can always use our own constants.feature(new_uninit).pin-initAPI.BoxAPIs (which are the ones we need) do not seem to have concerns for stabilization. However, @tgross35 says:feature(ptr_metadata)(core::ptr::metadataandcore::ptr::from_raw_parts_mutfunctions).Arc, and potentially byimpl_zeroable!to include pointers to DSTs when their metadata isZeroablevia thePointeetrait.-Zcrate-attr.-Zfunction-sections(inrustc, it applies to data too).rustc: rust-lang/rust@6b130e3).Makefile(underCONFIG_LD_DEAD_CODE_DATA_ELIMINATION, which is experimental so far).-Zunpretty=expanded.RUSTC_BOOTSTRAP=1only for the target that uses it, if needed).-Zuse-sync-unwind=n.nremains the default.Low priority (we will likely not use them in the end)
feature(allocator_api).allocfork, but we are likely dropping it (https://lore.kernel.org/rust-for-linux/20240328013603.206764-1-wedsonaf@gmail.com/); otherwise: still quite open.feature(coerce_unsized)&feature(unsize)(core::ops::CoerceUnsizedandcore::marker::Unsizetraits).Arc.feature(derive_smart_pointer)instead to avoid depending onArc's needed features; otherwise: "theCoerceUnsizedtrait is unstable and we wish to revisit its design before stabilizing, so for now only stdlib types can be unsized" + there are unsoundness issues, seePinis unsound due to transitive effects ofCoerceUnsizedrust-lang/rust#68015 and APinunsoundness involving animpl DerefMut for Pin<&dyn LocalTrait>rust-lang/rust#85099. See https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/rust-for-linux.20custom.20arc.20unstable.20feature.20requirements.feature(dispatch_from_dyn)(core::ops::DispatchFromDyntrait).Arc.feature(derive_smart_pointer)instead to avoid depending onArc's needed features; otherwise: see https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/rust-for-linux.20custom.20arc.20unstable.20feature.20requirements.feature(pointer_is_aligned)(is_aligned_to).FromBytes(VFS abstractions, Useis_aligned_toinFromBytesonce it's available #1038).is_aligned()) got stabilized in 1.79 (stabilize ptr.is_aligned, move ptr.is_aligned_to to a new feature gate rust-lang/rust#121948).is_aligned_to()may be stabilized, but it needs to be justified.feature(more_fallible_allocation_methods).more_fallible_allocation_methodsrust-lang/rust#86942.alloc.allocfork, but we are likely dropping it (https://lore.kernel.org/rust-for-linux/20240328013603.206764-1-wedsonaf@gmail.com/); otherwise: unknown.feature(receiver_trait)(core::ops::Receivertrait).Arc.feature(derive_smart_pointer)instead to avoid depending onArc's needed features; otherwise: see https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/rust-for-linux.20custom.20arc.20unstable.20feature.20requirements. Another potential solution might befeature(arbitrary_self_types)(Tracking issue for RFC 3519:arbitrary_self_typesrust-lang/rust#44874), though it has different tradeoffs.Done (i.e. stabilized, or not needed anymore, etc.)
--check-cfg.--check-cfgoption rust-lang/rust#123501).cfgs): Limit the number of names and values in check-cfg diagnostics rust-lang/rust#121202 (1.78).CARGO_CRATE_NAMEinstead ofCARGOas a better heuristic for Cargo diagnostics): Use better heuristic for printing Cargo specific diagnostics rust-lang/rust#121237 (1.78).feature(alloc_error_handler).no_global_oom_handling.feature(bench_black_box).std::hint::black_boxrust-lang/rust#64102.samples/rust/rust_stack_probing.rs.feature(concat_idents).concat_identsrust-lang/rust#29599.drivers/android/defs.rsin the past, nothing now.pastecrate is an alternative (or, in general, generating code). We ended up using a proc macro on our side Re-implement concat_idents! in libmacros #826.feature(const_fn_transmute).rust/kernel/str.rs.const_fn_transmute,const_fn_unionrust-lang/rust#85769). It is one of the subfeatures ofconst_fn.feature(const_fn_trait_bound).const fnrust-lang/rust#57563.rust/kernel/file_operations.rsandrust/kernel/module_param.rs.const_fn.feature(const_maybe_uninit_zeroed).const_maybe_uninit_zeroedrust-lang/rust#91850.const_maybe_uninit_zeroedandconst_mem_zeroedrust-lang/rust#116218).feature(const_panic).rust/kernel/print.rs.const_panicrust-lang/rust#89508). It is one of the subfeatures ofconst_fn.feature(const_ptr_offset_from).rust/kernel/driver.rs.const_ptr_offset_from. rust-lang/rust#96240).feature(const_raw_ptr_deref)rust/kernel/str.rs.const_fn_transmutesince that was getting stabilized sooner.feature(const_unreachable_unchecked).unreachable_uncheckedrust-lang/rust#53188.rust/kernel/str.rs.unreachable_uncheckedasconst fnrust-lang/rust#89509). It is one of the subfeatures ofconst_fn.feature(core_ffi_c)module!, etc.core::ffi:c_*and re-export instd::ffirust-lang/rust#98315).feature(core_panic).rust/build_assert.rs.panic!("{}", msg)(2021 edition, allowed in const context since Allowpanic!("{}", computed_str)in const fn. rust-lang/rust#88954).feature(explicit_generic_args_with_impl_trait)explicit_generic_args_with_impl_traitrust-lang/rust#83701.pinned-init.feature(generic_associated_types).rust/kernel/types.rs(PointerWrapper),rust/kernel/file_operations.rs(IoctlHandler).feature(global_asm).rust/module.rsproc macro.module.rs, use codegen instead #77.feature(let_else).let_elsehelps naturally with that (when applicable).rust/macros/paste.rsand potentially everywhere.let elserust-lang/rust#93628).feature(maybe_uninit_extra).#![feature(maybe_uninit_extra,const_maybe_uninit_write)]rust-lang/rust#63567.rust/kernel/miscdev.rs.maybe_uninit_extrarust-lang/rust#92768) (non-const only, which is the only part we need).feature(offset_of)(single-field, i.e. noenum, no nested).#![feature(offset_of)]rust-lang/rust#106655.rust/kernel/workqueue.rsandkernel/kasync/executor/workqueue.rs(https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git/commit/?h=for-6.7-rust-bindings&id=7324b88975c525a013ae0db747df97924ce80675).feature(pin_macro).core::pin::pin!rust-lang/rust#93178.stack_pin_init!andstack_try_pin_init!.::{core,std}::pin::pin!rust-lang/rust#103800).feature(try_reserve).try_reserve: RFC 2116 fallible collection allocation rust-lang/rust#48043.rust/kernel/lib.rs.-Zallow-features.-Zbuild-std.rusttesttarget, back when we had a customalloc).allocanmore. The actual progress is not clear. Seestdwanted features & bugfixes #572.-Zsplit-dwarf-kind=split.splitstops being the default.splitis the default, we will not need it.-Zsymbol-mangling-version=v0.rust/exports.c.The text was updated successfully, but these errors were encountered: