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INFO: rcu detected stall in sys_timerfd_settime (4)

Status: upstream: reported on 2025/06/06 11:45
Reported-by: syzbot+2327d54f806b6e01214b@syzkaller.appspotmail.com
First crash: 76d, last: 12d
▶ ▼ 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 380d 420d 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 1377d 1445d 0/29 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in sys_timerfd_settime (4) fs 1 1 494d 494d 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 947d 947d 0/29 auto-obsoleted due to no activity on 2023/04/25 06:19
linux-6.1 INFO: rcu detected stall in sys_timerfd_settime (3) 1 2 64d 127d 0/3 upstream: reported on 2025/04/16 01:08
upstream INFO: rcu detected stall in sys_timerfd_settime (3) fs 1 2 589d 642d 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 194d 399d 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 799d 799d 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 791d 791d 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 273d 273d 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 245d 245d 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: 	1-...!: (1 GPs behind) idle=ad3/1/0x4000000000000000 softirq=29861/29862 fqs=134 
	(detected by 0, t=10506 jiffies, g=39337, q=2194)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10235 Comm: syz.5.1817 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31
Code: 41 5f 5d c3 48 c7 c7 57 57 b8 8b eb 0a 48 c7 c7 fc 68 a2 8b 48 89 de e8 18 86 e1 07 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 43 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9
RSP: 0018:ffffc90000dd0878 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88805fa21dc0 RCX: ffffffff815cacb4
RDX: 0000000000000008 RSI: 0000000000000008 RDI: ffffffff8ffb70c0
RBP: 0000000000000009 R08: dffffc0000000000 R09: fffffbfff1ff6e19
R10: fffffbfff1ff6e19 R11: 1ffffffff1ff6e18 R12: 0000000000000200
R13: dffffc0000000000 R14: ffff88805fa228b0 R15: 0000000000000015
FS:  00007f7364bf06c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c406246 CR3: 000000002af13000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:197 [inline]
 mark_lock+0x94/0x320 kernel/locking/lockdep.c:4569
 mark_usage kernel/locking/lockdep.c:4512 [inline]
 __lock_acquire+0xd5a/0x7c60 kernel/locking/lockdep.c:4966
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 advance_sched+0x6ca/0x940 net/sched/sch_taprio.c:769
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 7e db aa f7 48 89 df e8 46 b0 ab f7 e8 91 46 cc f7 fb bf 01 00 00 00 <e8> 76 d4 9f f7 65 8b 05 17 d4 50 76 85 c0 74 02 5b c3 e8 c4 de 4e
RSP: 0018:ffffc9000315fd20 EFLAGS: 00000282
RAX: 144ebb5de37e7800 RBX: ffff888061954888 RCX: 144ebb5de37e7800
RDX: dffffc0000000000 RSI: ffffffff8a0b15c0 RDI: 0000000000000001
RBP: 7fffffffffffffff R08: dffffc0000000000 R09: ffffed100c32a912
R10: ffffed100c32a912 R11: 1ffff1100c32a911 R12: 1ffff1100c32a910
R13: ffff888061954800 R14: ffff8880686e5b81 R15: 7fffffffffffffff
 spin_unlock_irq include/linux/spinlock.h:413 [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:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f7366988be9
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:00007f7364bf0038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007f7366baffa0 RCX: 00007f7366988be9
RDX: 0000200000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007f7366a0be19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7366bb0038 R14: 00007f7366baffa0 R15: 00007ffd78068268
 </TASK>
rcu: rcu_preempt kthread starved for 9835 jiffies! g39337 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:28032 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 9363 Comm: kworker/0:18 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events jump_label_update_timeout
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969
Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 a6 46 0b 00 83 e3 01 75 07 e8 3c 43 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7
RSP: 0018:ffffc9000319f940 EFLAGS: 00000293
RAX: ffffffff816c810b RBX: 0000000000000001 RCX: ffff888020b88000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000319fa80 R08: dffffc0000000000 R09: fffffbfff1ff6e19
R10: fffffbfff1ff6e19 R11: 1ffffffff1ff6e18 R12: ffff8880b9140588
R13: 1ffff110172280b1 R14: ffff8880b903b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1442 [inline]
 text_poke_bp_batch+0x2a9/0x7c0 arch/x86/kernel/alternative.c:1642
 text_poke_flush arch/x86/kernel/alternative.c:1833 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1840
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 __static_key_slow_dec_cpuslocked+0xf0/0x150 kernel/jump_label.c:248
 __static_key_slow_dec kernel/jump_label.c:255 [inline]
 jump_label_update_timeout+0x1a/0x20 kernel/jump_label.c:263
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/08 15:41 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_timerfd_settime
2025/08/05 11:57 linux-5.15.y c79648372d02 37880f40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_timerfd_settime
2025/07/04 16:19 linux-5.15.y 3dea0e7f549e d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_timerfd_settime
2025/06/11 18:36 linux-5.15.y 1c700860e8bc 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_timerfd_settime
2025/06/06 11:44 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_timerfd_settime
* Struck through repros no longer work on HEAD.