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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: 21h54m, last: 21h54m
▶ ▼ Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_timerfd_settime (2) 3 305d 345d 0/3 auto-obsoleted due to no activity on 2024/11/14 05:49
upstream INFO: rcu detected stall in sys_timerfd_settime fs 3 1302d 1370d 0/28 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in sys_timerfd_settime (4) fs 1 419d 419d 0/28 auto-obsoleted due to no activity on 2024/06/12 13:14
upstream INFO: rcu detected stall in sys_timerfd_settime (2) net 1 872d 872d 0/28 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 52d 52d 0/3 upstream: reported on 2025/04/16 01:08
upstream INFO: rcu detected stall in sys_timerfd_settime (3) fs 2 514d 566d 0/28 auto-obsoleted due to no activity on 2024/04/09 00:01
upstream INFO: rcu detected stall in sys_timerfd_settime (5) fs 17 119d 323d 0/28 auto-obsoleted due to no activity on 2025/05/09 08:53
linux-5.15 INFO: rcu detected stall in sys_timerfd_settime 1 724d 724d 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 716d 716d 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 198d 198d 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 170d 170d 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=381/1/0x4000000000000000 softirq=21020/21020 fqs=0 
	(detected by 1, t=10504 jiffies, g=28781, q=918)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7771 Comm: syz.2.1021 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
RIP: 0010:do_raw_spin_lock+0xa0/0x280 kernel/locking/spinlock_debug.c:114
Code: 0f b6 04 38 84 c0 0f 85 9a 01 00 00 41 8b 06 3d ad 4e ad de 0f 85 16 01 00 00 4c 8d 63 10 4d 89 e6 49 c1 ee 03 43 80 3c 3e 00 <74> 08 4c 89 e7 e8 a6 01 60 00 49 8b 04 24 65 48 8b 0d 2a 37 a5 7e
RSP: 0018:ffffc90000007b40 EFLAGS: 00000046
RAX: 00000000dead4ead RBX: ffffffff96325a48 RCX: 1ffff92000000f6c
RDX: 0000000000000000 RSI: ffffffff8a0b2460 RDI: ffffffff96325a48
RBP: ffffc90000007bf0 R08: dffffc0000000000 R09: fffffbfff1ff3619
R10: fffffbfff1ff3619 R11: 1ffffffff1ff3618 R12: ffffffff96325a58
R13: ffffffff96325a40 R14: 1ffffffff2c64b4b R15: dffffc0000000000
FS:  00007fca3d3566c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3071eff8 CR3: 0000000060499000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]
 _raw_spin_lock_irqsave+0xb0/0xf0 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x63/0x340 lib/debugobjects.c:749
 debug_hrtimer_deactivate kernel/time/hrtimer.c:415 [inline]
 debug_deactivate+0x1d/0x1c0 kernel/time/hrtimer.c:471
 __run_hrtimer kernel/time/hrtimer.c:1658 [inline]
 __hrtimer_run_queues+0x2db/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 9a b1 f7 48 89 df e8 56 6f b2 f7 e8 a1 13 d3 f7 fb bf 01 00 00 00 <e8> 86 93 a6 f7 65 8b 05 27 a3 57 76 85 c0 74 02 5b c3 e8 d4 ad 55
RSP: 0018:ffffc9000357fd20 EFLAGS: 00000282
RAX: 1bf230984a6c1600 RBX: ffff88805e4dd888 RCX: 1bf230984a6c1600
RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001
RBP: 7fffffffffffffff R08: dffffc0000000000 R09: ffffed100bc9bb12
R10: ffffed100bc9bb12 R11: 1ffff1100bc9bb11 R12: 1ffff1100bc9bb10
R13: ffff88805e4dd800 R14: ffff888076ead401 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: 0033:0x7fca3f4ee929
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:00007fca3d356038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007fca3f715fa0 RCX: 00007fca3f4ee929
RDX: 0000200000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007fca3f570b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fca3f715fa0 R15: 00007ffe99eed138
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10503 jiffies! g28781 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=11442
rcu: rcu_preempt kthread starved for 10504 jiffies! g28781 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:27008 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7771 Comm: syz.2.1021 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__lock_release kernel/locking/lockdep.c:5311 [inline]
RIP: 0010:lock_release+0x254/0x870 kernel/locking/lockdep.c:5643
Code: 83 3e 00 0f 85 ca 03 00 00 4d 8d 74 24 20 4c 89 f3 48 c1 eb 03 42 0f b6 04 2b 84 c0 4c 8b 7c 24 20 0f 85 90 04 00 00 41 8b 06 <3d> 00 00 10 00 72 3c 89 c1 81 e1 00 00 f0 ff 25 ff ff 0f 00 8d bc
RSP: 0018:ffffc90000007ae0 EFLAGS: 00000046
RAX: 00000000000c4000 RBX: 1ffff1100497c167 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffffffff96325a60 RDI: ffff888024be0b18
RBP: ffffc90000007bf0 R08: dffffc0000000000 R09: fffffbfff1ad157e
R10: fffffbfff1ad157e R11: 1ffffffff1ad157d R12: ffff888024be0b18
R13: dffffc0000000000 R14: ffff888024be0b38 R15: 1ffff92000000f68
FS:  00007fca3d3566c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3071eff8 CR3: 0000000060499000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_unlock_irqrestore+0x6d/0x100 kernel/locking/spinlock.c:194
 debug_object_activate+0x2d2/0x480 lib/debugobjects.c:712
 debug_hrtimer_activate kernel/time/hrtimer.c:410 [inline]
 debug_activate kernel/time/hrtimer.c:465 [inline]
 enqueue_hrtimer+0x30/0x370 kernel/time/hrtimer.c:1074
 __run_hrtimer kernel/time/hrtimer.c:1707 [inline]
 __hrtimer_run_queues+0x65a/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 9a b1 f7 48 89 df e8 56 6f b2 f7 e8 a1 13 d3 f7 fb bf 01 00 00 00 <e8> 86 93 a6 f7 65 8b 05 27 a3 57 76 85 c0 74 02 5b c3 e8 d4 ad 55
RSP: 0018:ffffc9000357fd20 EFLAGS: 00000282
RAX: 1bf230984a6c1600 RBX: ffff88805e4dd888 RCX: 1bf230984a6c1600
RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001
RBP: 7fffffffffffffff R08: dffffc0000000000 R09: ffffed100bc9bb12
R10: ffffed100bc9bb12 R11: 1ffff1100bc9bb11 R12: 1ffff1100bc9bb10
R13: ffff88805e4dd800 R14: ffff888076ead401 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: 0033:0x7fca3f4ee929
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:00007fca3d356038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007fca3f715fa0 RCX: 00007fca3f4ee929
RDX: 0000200000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007fca3f570b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fca3f715fa0 R15: 00007ffe99eed138
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.