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INFO: rcu detected stall in cleanup_mnt

Status: auto-obsoleted due to no activity on 2023/09/19 04:00
Reported-by: syzbot+2a4bf7ea4cf07ea05987@syzkaller.appspotmail.com
First crash: 529d, last: 529d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in cleanup_mnt (2) block 1 1065d 1065d 0/28 closed as invalid on 2022/02/08 10:10
linux-6.1 INFO: rcu detected stall in cleanup_mnt (2) 1 158d 158d 0/3 auto-obsoleted due to no activity on 2024/09/23 19:34
linux-6.1 INFO: rcu detected stall in cleanup_mnt 1 474d 474d 0/3 auto-obsoleted due to no activity on 2023/11/13 00:06
upstream INFO: rcu detected stall in cleanup_mnt exfat 1 1596d 1596d 0/28 auto-closed as invalid on 2020/09/06 14:28
upstream INFO: rcu detected stall in cleanup_mnt (3) reiserfs block 2 540d 550d 0/28 auto-obsoleted due to no activity on 2023/08/29 03:36
linux-5.15 INFO: rcu detected stall in cleanup_mnt (2) origin:lts-only syz done 4 30d 102d 0/3 upstream: reported syz repro on 2024/08/10 23:43

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=17f/1/0x4000000000000000 softirq=67315/67315 fqs=0 
	(detected by 1, t=10502 jiffies, g=95557, q=597)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3547 Comm: syz-executor.4 Not tainted 5.15.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:lockdep_recursion_inc kernel/locking/lockdep.c:431 [inline]
RIP: 0010:lock_is_held_type+0x6a/0x180 kernel/locking/lockdep.c:5664
Code: 2d 9b 84 e7 75 41 83 bd ec 0a 00 00 00 0f 85 db 00 00 00 41 89 f6 49 89 ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 4c 8b 24 24 fa <48> c7 c7 60 0a 8b 8a e8 0a 12 00 00 65 ff 05 a3 8d e7 75 41 83 bd
RSP: 0018:ffffc90000007d18 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88807ce45940
RDX: ffff88807ce45940 RSI: 00000000ffffffff RDI: ffff8880b9a2a218
RBP: 00000000ffffffff R08: ffffffff816f20bb R09: ffff88807cd0c340
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000046
R13: ffff88807ce45940 R14: 00000000ffffffff R15: ffff8880b9a2a218
FS:  0000555556a78400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555557436708 CR3: 000000003ed7d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_is_held include/linux/lockdep.h:287 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1651 [inline]
 __hrtimer_run_queues+0x2f1/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:preempt_schedule_irq+0xf2/0x1c0 kernel/sched/core.c:6776
Code: 89 f5 49 c1 ed 03 eb 0d 48 f7 03 08 00 00 00 0f 84 97 00 00 00 bf 01 00 00 00 e8 59 f3 33 f7 e8 44 3b 63 f7 fb bf 01 00 00 00 <e8> c9 b3 ff ff 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 e9 25 a6 f7 48
RSP: 0018:ffffc9000307fa80 EFLAGS: 00000282
RAX: 97b66edd26312c00 RBX: 1ffff9200060ff58 RCX: ffffffff8162db08
RDX: dffffc0000000000 RSI: ffffffff8a8afc60 RDI: 0000000000000001
RBP: ffffc9000307fb30 R08: dffffc0000000000 R09: fffffbfff1f79650
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200060ff50
R13: 1ffff9200060ff54 R14: ffffc9000307faa0 R15: dffffc0000000000
 irqentry_exit+0x53/0x80 kernel/entry/common.c:426
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
RIP: 0010:synchronize_rcu+0x0/0x1a0 kernel/rcu/tree.c:3746
Code: e8 b5 49 5e 00 e9 68 fd ff ff 48 c7 c7 20 12 92 8c 48 89 de e8 21 e0 bc 02 e9 b5 fa ff ff e8 b7 dd af 08 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 54 53 48 83 e4 e0 48 81 ec 00 01 00 00
RSP: 0018:ffffc9000307fbf8 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff9200060ff88 RCX: ffffffff913c3003
RDX: 0000000000000000 RSI: ffffffff8a8b0a60 RDI: ffffffff8ad86000
RBP: ffffc9000307fcd8 R08: dffffc0000000000 R09: fffffbfff22cef17
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff913ae7b8
R13: 1ffff9200060ff84 R14: 0000000000000206 R15: ffffc9000307fc40
 lockdep_unregister_key+0x4e6/0x5b0 kernel/locking/lockdep.c:6318
 wq_unregister_lockdep kernel/workqueue.c:3506 [inline]
 destroy_workqueue+0x81f/0xae0 kernel/workqueue.c:4473
 xfs_destroy_mount_workqueues+0x3b/0x100 fs/xfs/xfs_super.c:572
 xfs_fs_put_super+0x22c/0x2b0 fs/xfs/xfs_super.c:1097
 generic_shutdown_super+0x136/0x2c0 fs/super.c:475
 kill_block_super+0x7a/0xe0 fs/super.c:1405
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fc8f02fa5d7
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffce9266b18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fc8f02fa5d7
RDX: 00007ffce9266beb RSI: 000000000000000a RDI: 00007ffce9266be0
RBP: 00007ffce9266be0 R08: 00000000ffffffff R09: 00007ffce92669b0
R10: 0000555556a79893 R11: 0000000000000246 R12: 00007fc8f0353cdc
R13: 00007ffce9267ca0 R14: 0000555556a79810 R15: 00007ffce9267ce0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g95557 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=62795
rcu: rcu_preempt kthread starved for 10502 jiffies! g95557 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25592 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3547 Comm: syz-executor.4 Not tainted 5.15.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x81/0x290 mm/kasan/generic.c:189
Code: df 4f 8d 34 1a 4c 89 f5 4c 29 cd 48 83 fd 10 7f 26 48 85 ed 0f 84 3a 01 00 00 49 f7 d2 49 01 da 41 80 39 00 0f 85 c4 01 00 00 <49> ff c1 49 ff c2 75 ee e9 1d 01 00 00 45 89 cf 41 83 e7 07 0f 84
RSP: 0018:ffffc90000007d38 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffffffff1bc786d RCX: ffffffff816f23d6
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8de3c368
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1bc786d
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8880b9a2a200
R13: 0000000000000001 R14: fffffbfff1bc786e R15: ffff88807ce46418
FS:  0000555556a78400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555557436708 CR3: 000000003ed7d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_hrtimer_expire_exit include/trace/events/timer.h:279 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x5f6/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:preempt_schedule_irq+0xf2/0x1c0 kernel/sched/core.c:6776
Code: 89 f5 49 c1 ed 03 eb 0d 48 f7 03 08 00 00 00 0f 84 97 00 00 00 bf 01 00 00 00 e8 59 f3 33 f7 e8 44 3b 63 f7 fb bf 01 00 00 00 <e8> c9 b3 ff ff 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 e9 25 a6 f7 48
RSP: 0018:ffffc9000307fa80 EFLAGS: 00000282
RAX: 97b66edd26312c00 RBX: 1ffff9200060ff58 RCX: ffffffff8162db08
RDX: dffffc0000000000 RSI: ffffffff8a8afc60 RDI: 0000000000000001
RBP: ffffc9000307fb30 R08: dffffc0000000000 R09: fffffbfff1f79650
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200060ff50
R13: 1ffff9200060ff54 R14: ffffc9000307faa0 R15: dffffc0000000000
 irqentry_exit+0x53/0x80 kernel/entry/common.c:426
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
RIP: 0010:synchronize_rcu+0x0/0x1a0 kernel/rcu/tree.c:3746
Code: e8 b5 49 5e 00 e9 68 fd ff ff 48 c7 c7 20 12 92 8c 48 89 de e8 21 e0 bc 02 e9 b5 fa ff ff e8 b7 dd af 08 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 54 53 48 83 e4 e0 48 81 ec 00 01 00 00
RSP: 0018:ffffc9000307fbf8 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff9200060ff88 RCX: ffffffff913c3003
RDX: 0000000000000000 RSI: ffffffff8a8b0a60 RDI: ffffffff8ad86000
RBP: ffffc9000307fcd8 R08: dffffc0000000000 R09: fffffbfff22cef17
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff913ae7b8
R13: 1ffff9200060ff84 R14: 0000000000000206 R15: ffffc9000307fc40
 lockdep_unregister_key+0x4e6/0x5b0 kernel/locking/lockdep.c:6318
 wq_unregister_lockdep kernel/workqueue.c:3506 [inline]
 destroy_workqueue+0x81f/0xae0 kernel/workqueue.c:4473
 xfs_destroy_mount_workqueues+0x3b/0x100 fs/xfs/xfs_super.c:572
 xfs_fs_put_super+0x22c/0x2b0 fs/xfs/xfs_super.c:1097
 generic_shutdown_super+0x136/0x2c0 fs/super.c:475
 kill_block_super+0x7a/0xe0 fs/super.c:1405
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fc8f02fa5d7
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffce9266b18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fc8f02fa5d7
RDX: 00007ffce9266beb RSI: 000000000000000a RDI: 00007ffce9266be0
RBP: 00007ffce9266be0 R08: 00000000ffffffff R09: 00007ffce92669b0
R10: 0000555556a79893 R11: 0000000000000246 R12: 00007fc8f0353cdc
R13: 00007ffce9267ca0 R14: 0000555556a79810 R15: 00007ffce9267ce0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/11 03:58 linux-5.15.y 7349e40704a0 49519f06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_mnt
* Struck through repros no longer work on HEAD.