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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: 47d, last: 19d
▶ ▼ 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 351d 391d 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 1349d 1416d 0/29 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in sys_timerfd_settime (4) fs 1 1 466d 466d 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 918d 918d 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 36d 98d 0/3 upstream: reported on 2025/04/16 01:08
upstream INFO: rcu detected stall in sys_timerfd_settime (3) fs 1 2 560d 613d 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 165d 370d 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 770d 770d 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 762d 762d 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 244d 244d 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 216d 216d 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-...!: (0 ticks this GP) idle=525/1/0x4000000000000000 softirq=18745/18745 fqs=14 
	(detected by 0, t=10502 jiffies, g=22941, q=139)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7237 Comm: syz.5.1027 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:hlock_id kernel/locking/lockdep.c:399 [inline]
RIP: 0010:__lock_acquire+0xf19/0x7c60 kernel/locking/lockdep.c:5000
Code: c7 44 24 60 00 00 00 00 eb 06 b0 01 89 44 24 60 4c 89 b4 24 c8 00 00 00 48 8b 44 24 58 42 0f b6 04 00 84 c0 0f 85 5f 5a 00 00 <45> 8b 24 24 48 83 7d 10 00 0f 84 a3 00 00 00 48 8b 84 24 88 00 00
RSP: 0018:ffffc90000dd08e0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff960c0f01
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffba0c8
RBP: ffffc90000dd0b30 R08: dffffc0000000000 R09: fffffbfff1ff741a
R10: fffffbfff1ff741a R11: 1ffffffff1ff7419 R12: ffff88801d2d6450
R13: ffff88801d2d5940 R14: 1ffff11003a5ac84 R15: ffffffffffffffff
FS:  00007f6c6a19d6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c34c3cc CR3: 00000000568eb000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0x9f/0xe0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1694 [inline]
 __hrtimer_run_queues+0x5ff/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 8e 7b a9 f7 48 89 df e8 56 50 aa f7 e8 91 f5 ca f7 fb bf 01 00 00 00 <e8> 86 74 9e f7 65 8b 05 27 84 4f 76 85 c0 74 02 5b c3 e8 d4 8e 4d
RSP: 0018:ffffc900046efd20 EFLAGS: 00000282
RAX: 32a2098aaae66c00 RBX: ffff888060075088 RCX: 32a2098aaae66c00
RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001
RBP: 7fffffffffffffff R08: dffffc0000000000 R09: ffffed100c00ea12
R10: ffffed100c00ea12 R11: 1ffff1100c00ea11 R12: 1ffff1100c00ea10
R13: ffff888060075000 R14: ffff8880764ac281 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: 0033:0x7f6c6c335929
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:00007f6c6a19d038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007f6c6c55cfa0 RCX: 00007f6c6c335929
RDX: 0000200000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007f6c6c3b7b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6c6c55cfa0 R15: 00007fff06bb0fc8
 </TASK>
rcu: rcu_preempt kthread starved for 10430 jiffies! g22941 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: 4229 Comm: kworker/0:4 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events bpf_prog_free_deferred
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:3932 [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+0xb92/0xd70 kernel/smp.c:969
Code: 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 a6 55 0b 00 83 e3 01 75 07 e8 3c 52 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 04 24 01 00 00 00 74 1e e8 15
RSP: 0018:ffffc900030ff840 EFLAGS: 00000293
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffff888062e93b80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900030ff980 R08: dffffc0000000000 R09: fffffbfff1ff741a
R10: fffffbfff1ff741a R11: 1ffffffff1ff7419 R12: ffff8880b9140588
R13: 1ffff110172280b1 R14: ffff8880b903b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 __purge_vmap_area_lazy+0x216/0x18f0 mm/vmalloc.c:1683
 _vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2107
 vm_remove_mappings mm/vmalloc.c:2584 [inline]
 __vunmap+0x70d/0xa40 mm/vmalloc.c:2611
 bpf_jit_binary_free kernel/bpf/core.c:918 [inline]
 bpf_jit_free+0x92/0x180 kernel/bpf/core.c:931
 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 (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.