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INFO: rcu detected stall in do_faccessat (4)

Status: auto-closed as invalid on 2021/09/26 22:47
Subsystems: fs
[Documentation on labels]
First crash: 1487d, last: 1487d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in do_faccessat (6) kernel 1 1 601d 601d 0/29 auto-obsoleted due to no activity on 2024/02/29 22:48
linux-5.15 INFO: rcu detected stall in do_faccessat 1 1 61d 61d 0/3 upstream: reported on 2025/06/24 03:01
upstream INFO: rcu detected stall in do_faccessat (7) fs 1 1 225d 225d 0/29 auto-obsoleted due to no activity on 2025/04/10 08:15
upstream INFO: rcu detected stall in do_faccessat (2) fs 1 1 1803d 1803d 0/29 auto-closed as invalid on 2020/12/14 19:23
upstream INFO: rcu detected stall in do_faccessat (3) fs 1 1 1706d 1706d 0/29 auto-closed as invalid on 2021/03/21 19:47
upstream INFO: rcu detected stall in do_faccessat (5) fs 1 2 1384d 1404d 0/29 auto-closed as invalid on 2022/02/07 01:08
upstream INFO: rcu detected stall in do_faccessat fs 1 1 1901d 1901d 0/29 auto-closed as invalid on 2020/09/07 18:08

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=8e7/1/0x4000000000000000 softirq=184185/184187 fqs=0 
	(detected by 0, t=10502 jiffies, g=355385, q=75)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 442 Comm: systemd-udevd Not tainted 5.14.0-rc3-next-20210727-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_acquire+0x27e/0x54a0 kernel/locking/lockdep.c:4950
Code: b7 44 24 20 49 8d 7c 24 08 48 89 fa 48 c1 ea 03 66 25 00 e0 09 c8 66 41 89 44 24 20 48 b8 00 00 00 00 00 fc ff df 80 3c 02 00 <0f> 85 43 3b 00 00 48 8b 84 24 28 01 00 00 49 8d 7c 24 10 48 89 fa
RSP: 0018:ffffc90000dc0ad0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff903e5a30 RCX: 0000000000000000
RDX: 1ffff110050f94df RSI: 000000000000005b RDI: ffff8880287ca6f8
RBP: 0000000000000000 R08: 1ffff110050f94dd R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880287ca6f0
R13: ffff8880287c9c80 R14: 0000000000000000 R15: 0000000000000001
FS:  00007f20bc6778c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000005451f8 CR3: 00000000310f9000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159
 debug_object_activate+0x12e/0x3e0 lib/debugobjects.c:656
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:475 [inline]
 enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:982
 __run_hrtimer kernel/time/hrtimer.c:1554 [inline]
 __hrtimer_run_queues+0xb02/0xe50 kernel/time/hrtimer.c:1601
 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:191
Code: 74 24 10 e8 7a a3 2b f8 48 89 ef e8 22 19 2c f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 13 f1 1f f8 65 8b 05 bc 67 d2 76 85 c0 74 0a 5b 5d c3 e8 50 64
RSP: 0018:ffffc9000258f910 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff1fa05f2
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000001
RBP: ffffc9000258fa80 R08: 0000000000000001 R09: ffffffff8fcfd8af
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:414 [inline]
 __wake_up_common_lock+0xde/0x130 kernel/sched/wait.c:140
 __d_lookup_done+0x201/0x4b0 fs/dcache.c:2685
 d_lookup_done include/linux/dcache.h:373 [inline]
 d_lookup_done include/linux/dcache.h:369 [inline]
 __lookup_slow+0x3d0/0x480 fs/namei.c:1647
 lookup_slow fs/namei.c:1663 [inline]
 walk_component+0x40f/0x6a0 fs/namei.c:1959
 lookup_last fs/namei.c:2414 [inline]
 path_lookupat+0x1bb/0x860 fs/namei.c:2438
 filename_lookup+0x1c6/0x5b0 fs/namei.c:2467
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x127/0x850 fs/open.c:425
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f20bb4e99c7
Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe95a83038 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 000055c96814f880 RCX: 00007f20bb4e99c7
RDX: 00746e657665752f RSI: 0000000000000000 RDI: 00007ffe95a83040
RBP: 00007ffe95a830b0 R08: 000000000000f000 R09: 0000000000001010
R10: 0000000000000020 R11: 0000000000000246 R12: 000055c9665bc856
R13: 000055c968152eb0 R14: 00007ffe95a83040 R15: 000055c96815d248
rcu: rcu_preempt kthread starved for 10502 jiffies! g355385 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28720 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4700 [inline]
 __schedule+0x949/0x2710 kernel/sched/core.c:5957
 schedule+0xd3/0x290 kernel/sched/core.c:6036
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1879
 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1963
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 445 Comm: syz-executor.2 Not tainted 5.14.0-rc3-next-20210727-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481
 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3886 [inline]
 rcu_sched_clock_irq+0x2125/0x2200 kernel/rcu/tree.c:2605
 update_process_times+0x16d/0x200 kernel/time/timer.c:1783
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421
 __run_hrtimer kernel/time/hrtimer.c:1537 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1601
 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:check_kcov_mode+0x31/0x40 kernel/kcov.c:175
Code: 89 c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 8b 96 3c 15 00 00 85 d2 74 0b 8b 86 18 15 00 00 39 f8 0f 94 c0 <c3> 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 31 c0 65 8b 15 77 30
RSP: 0018:ffffc9000249fca0 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffff8880b9d55b60 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffff8880287c8000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff816a7fd6 R11: 0000000000000000 R12: ffffed10173aab6d
R13: 0000000000000001 R14: ffff8880b9d55b68 R15: 0000000000000001
 write_comp_data kernel/kcov.c:218 [inline]
 __sanitizer_cov_trace_const_cmp4+0x1c/0x70 kernel/kcov.c:284
 csd_lock_wait kernel/smp.c:440 [inline]
 smp_call_function_many_cond+0x476/0xc20 kernel/smp.c:967
 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1133
 on_each_cpu include/linux/smp.h:71 [inline]
 clock_was_set+0x21/0x30 kernel/time/hrtimer.c:889
 do_settimeofday64 kernel/time/timekeeping.c:1327 [inline]
 do_settimeofday64+0x3dd/0x5c0 kernel/time/timekeeping.c:1293
 do_sys_settimeofday64 kernel/time/time.c:195 [inline]
 do_sys_settimeofday64+0x1de/0x260 kernel/time/time.c:169
 __do_sys_clock_settime kernel/time/posix-timers.c:1079 [inline]
 __se_sys_clock_settime kernel/time/posix-timers.c:1067 [inline]
 __x64_sys_clock_settime+0x1a1/0x280 kernel/time/posix-timers.c:1067
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665e9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe10750f188 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000000
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffdb79565bf R14: 00007fe10750f300 R15: 0000000000022000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/07/28 22:46 linux-next 42d0b5f52c9b 9a4781d4 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in do_faccessat
* Struck through repros no longer work on HEAD.