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INFO: rcu detected stall in sys_timerfd_settime (3)

Status: upstream: reported on 2025/04/16 01:08
Reported-by: syzbot+c67f6a9bb931ba170dea@syzkaller.appspotmail.com
First crash: 137d, last: 2d21h
▶ ▼ Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_timerfd_settime (2) 1 3 390d 430d 0/3 auto-obsoleted due to no activity on 2024/11/14 05:49
upstream INFO: rcu detected stall in sys_timerfd_settime fs 1 3 1388d 1455d 0/29 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in sys_timerfd_settime (4) fs 1 1 505d 505d 0/29 auto-obsoleted due to no activity on 2024/06/12 13:14
upstream INFO: rcu detected stall in sys_timerfd_settime (2) net 1 1 957d 957d 0/29 auto-obsoleted due to no activity on 2023/04/25 06:19
linux-5.15 INFO: rcu detected stall in sys_timerfd_settime (4) 1 5 23d 86d 0/3 upstream: reported on 2025/06/06 11:45
upstream INFO: rcu detected stall in sys_timerfd_settime (3) fs 1 2 599d 652d 0/29 auto-obsoleted due to no activity on 2024/04/09 00:01
upstream INFO: rcu detected stall in sys_timerfd_settime (5) fs 1 17 204d 409d 0/29 auto-obsoleted due to no activity on 2025/05/09 08:53
linux-5.15 INFO: rcu detected stall in sys_timerfd_settime 1 1 809d 809d 0/3 auto-obsoleted due to no activity on 2023/09/22 02:06
linux-6.1 INFO: rcu detected stall in sys_timerfd_settime 1 1 801d 801d 0/3 auto-obsoleted due to no activity on 2023/09/29 23:03
linux-5.15 INFO: rcu detected stall in sys_timerfd_settime (3) 1 1 283d 283d 0/3 auto-obsoleted due to no activity on 2025/03/01 03:09
linux-6.1 INFO: rcu detected stall in sys_timerfd_settime (2) 1 1 255d 255d 0/3 auto-obsoleted due to no activity on 2025/03/29 01:59

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=cbbc/1/0x4000000000000000 softirq=50984/50984 fqs=0
	(detected by 1, t=10506 jiffies, g=68441, q=243 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11846 Comm: syz.0.2712 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [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+0x74/0x290 mm/kasan/generic.c:189
Code: df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 <4c> 01 db 41 80 39 00 0f 85 c1 01 00 00 49 ff c1 48 ff c3 75 ee e9
RSP: 0018:ffffc90000007800 EFLAGS: 00000002
RAX: 0000000000000001 RBX: e00000000dea3db7 RCX: ffffffff8163aab4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90ae1240
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff215c248
R10: fffffbfff215c249 R11: 1ffffffff215c248 R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000000000001 R15: dffffc0000000001
FS:  00007fa4ef5c86c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3cc89e CR3: 000000004318c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 mark_lock+0x94/0x320 kernel/locking/lockdep.c:4606
 mark_usage kernel/locking/lockdep.c:4520 [inline]
 __lock_acquire+0xc25/0x7c50 kernel/locking/lockdep.c:5003
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
 debug_object_activate+0x6a/0x490 lib/debugobjects.c:698
 debug_hrtimer_activate kernel/time/hrtimer.c:448 [inline]
 debug_activate kernel/time/hrtimer.c:503 [inline]
 enqueue_hrtimer+0x30/0x3f0 kernel/time/hrtimer.c:1110
 __run_hrtimer kernel/time/hrtimer.c:1769 [inline]
 __hrtimer_run_queues+0x68e/0xd60 kernel/time/hrtimer.c:1816
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1878
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 18 42 f7 48 89 df e8 e6 dd 42 f7 e8 61 d1 65 f7 fb bf 01 00 00 00 <e8> 46 5b 36 f7 65 8b 05 67 14 e1 75 85 c0 74 02 5b c3 e8 b4 25 df
RSP: 0018:ffffc9000c927d20 EFLAGS: 00000282
RAX: 532741bfbfe30c00 RBX: ffff8880564cb488 RCX: 532741bfbfe30c00
RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: 0000000000000001
RBP: 7fffffffffffffff R08: dffffc0000000000 R09: ffffed100ac99692
R10: ffffed100ac99692 R11: 1ffff1100ac99691 R12: 1ffff1100ac99690
R13: ffff8880564cb400 R14: ffff88807c51b401 R15: 7fffffffffffffff
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 do_timerfd_settime+0xe3a/0x1080 fs/timerfd.c:521
 __do_sys_timerfd_settime fs/timerfd.c:567 [inline]
 __se_sys_timerfd_settime fs/timerfd.c:558 [inline]
 __x64_sys_timerfd_settime+0x15e/0x210 fs/timerfd.c:558
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa4ee78ebe9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa4ef5c8038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007fa4ee9b5fa0 RCX: 00007fa4ee78ebe9
RDX: 0000200000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007fa4ee811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa4ee9b6038 R14: 00007fa4ee9b5fa0 R15: 00007fffa941ac98
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g68441 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=29512
rcu: rcu_preempt kthread starved for 10506 jiffies! g68441 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:26496 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </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: 11846 Comm: syz.0.2712 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:122 [inline]
RIP: 0010:lock_acquire+0x133/0x490 kernel/locking/lockdep.c:5638
Code: 3d a5 b3 bc 0c 00 0f 84 f1 00 00 00 65 8b 05 34 87 9f 7e 85 c0 0f 85 2f 01 00 00 65 4c 8b 35 e4 7c 9f 7e 49 81 c6 dc 0a 00 00 <4c> 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 19 02 00 00 41 83
RSP: 0018:ffffc90000007b40 EFLAGS: 00000086
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 532741bfbfe30c00
RDX: 0000000000000000 RSI: ffffffff8adefac0 RDI: ffffffff8adefa80
RBP: ffffc90000007c58 R08: dffffc0000000000 R09: fffffbfff1c3ee26
R10: fffffbfff1c3ee26 R11: 1ffffffff1c3ee25 R12: 0000000000000000
R13: 1ffff92000000f74 R14: ffff888024e0465c R15: dffffc0000000000
FS:  00007fa4ef5c86c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3cc89e CR3: 000000004318c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0x47/0x970 net/sched/sch_taprio.c:700
 __run_hrtimer kernel/time/hrtimer.c:1752 [inline]
 __hrtimer_run_queues+0x554/0xd60 kernel/time/hrtimer.c:1816
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1878
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 18 42 f7 48 89 df e8 e6 dd 42 f7 e8 61 d1 65 f7 fb bf 01 00 00 00 <e8> 46 5b 36 f7 65 8b 05 67 14 e1 75 85 c0 74 02 5b c3 e8 b4 25 df
RSP: 0018:ffffc9000c927d20 EFLAGS: 00000282
RAX: 532741bfbfe30c00 RBX: ffff8880564cb488 RCX: 532741bfbfe30c00
RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: 0000000000000001
RBP: 7fffffffffffffff R08: dffffc0000000000 R09: ffffed100ac99692
R10: ffffed100ac99692 R11: 1ffff1100ac99691 R12: 1ffff1100ac99690
R13: ffff8880564cb400 R14: ffff88807c51b401 R15: 7fffffffffffffff
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 do_timerfd_settime+0xe3a/0x1080 fs/timerfd.c:521
 __do_sys_timerfd_settime fs/timerfd.c:567 [inline]
 __se_sys_timerfd_settime fs/timerfd.c:558 [inline]
 __x64_sys_timerfd_settime+0x15e/0x210 fs/timerfd.c:558
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa4ee78ebe9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa4ef5c8038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007fa4ee9b5fa0 RCX: 00007fa4ee78ebe9
RDX: 0000200000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007fa4ee811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa4ee9b6038 R14: 00007fa4ee9b5fa0 R15: 00007fffa941ac98
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/28 18:33 linux-6.1.y f89b6e15694c e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_timerfd_settime
2025/06/17 21:01 linux-6.1.y 58485ff1a74f e77fae15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_timerfd_settime
2025/04/16 01:07 linux-6.1.y 420102835862 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_timerfd_settime
* Struck through repros no longer work on HEAD.