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INFO: rcu detected stall in sys_clock_nanosleep (3)

Status: upstream: reported on 2025/01/22 19:59
Reported-by: syzbot+b63e85390d08ec9c5308@syzkaller.appspotmail.com
First crash: 62d, last: 14d
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_clock_nanosleep 1 562d 562d 0/3 auto-obsoleted due to no activity on 2023/12/20 18:13
linux-6.1 INFO: rcu detected stall in sys_clock_nanosleep (2) 4 286d 440d 0/3 auto-obsoleted due to no activity on 2024/09/21 09:26
upstream INFO: rcu detected stall in sys_clock_nanosleep (5) kernel C error done 91 1d18h 587d 0/28 upstream: reported C repro on 2023/08/17 09:25
upstream INFO: rcu detected stall in sys_clock_nanosleep (4) kernel 6 910d 1030d 0/28 auto-obsoleted due to no activity on 2022/12/31 21:43
upstream INFO: rcu detected stall in sys_clock_nanosleep (3) kernel 3 1208d 1217d 0/28 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in sys_clock_nanosleep kernel 1 1463d 1463d 0/28 auto-closed as invalid on 2021/06/22 18:23
linux-6.1 INFO: rcu detected stall in sys_clock_nanosleep 1 738d 738d 0/3 auto-obsoleted due to no activity on 2023/07/17 12:13
upstream INFO: rcu detected stall in sys_clock_nanosleep (2) kernel 1 1340d 1340d 0/28 auto-closed as invalid on 2021/10/22 22:53
linux-5.15 INFO: rcu detected stall in sys_clock_nanosleep (2) 2 364d 437d 0/3 auto-obsoleted due to no activity on 2024/07/04 20:17

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=979/1/0x4000000000000000 softirq=42117/42117 fqs=0 
	(detected by 1, t=10502 jiffies, g=51945, q=126)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9820 Comm: syz-executor Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:99 [inline]
RIP: 0010:do_raw_spin_unlock+0x1b/0x8b0 kernel/locking/spinlock_debug.c:140
Code: 07 db 08 66 2e 0f 1f 84 00 00 00 00 00 66 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 28 49 89 ff 48 bb 00 00 00 00 00 fc ff df <48> 8d 57 04 48 89 d0 48 c1 e8 03 48 89 44 24 10 0f b6 04 18 84 c0
RSP: 0018:ffffc90000007c50 EFLAGS: 00000086
RAX: 8fcb2aa0f745b900 RBX: dffffc0000000000 RCX: ffffc90000007b03
RDX: 0000000000000000 RSI: ffffffff8aab3e20 RDI: ffff88807c0dbae8
RBP: ffff88807c0dbae8 R08: dffffc0000000000 R09: fffffbfff1c150ee
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88807c0db800
R13: ffff88807c0dbb40 R14: dffffc0000000000 R15: ffff88807c0dbae8
FS:  00005555746ec500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555746ec808 CR3: 000000005078c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:151 [inline]
 _raw_spin_unlock+0x1a/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:403 [inline]
 advance_sched+0x68b/0x940 net/sched/sch_taprio.c:765
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 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_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 42 80 81 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e7 9e 0e f7 65 8b 05 f8 81 b9 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90002eafba0 EFLAGS: 00000206
RAX: 8fcb2aa0f745b900 RBX: 1ffff920005d5f78 RCX: ffffffff96a92f03
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: ffffc90002eafc30 R08: ffffffff81870420 R09: ffffed10171c5441
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff920005d5f74 R14: ffffc90002eafbc0 R15: 0000000000000246
 hrtimer_start_expires include/linux/hrtimer.h:434 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1968 [inline]
 do_nanosleep+0x164/0x7b0 kernel/time/hrtimer.c:2044
 hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2100
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1313 [inline]
 __se_sys_clock_nanosleep+0x323/0x3b0 kernel/time/posix-timers.c:1290
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ffaf4338a25
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007ffe785435a0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000142 RCX: 00007ffaf4338a25
RDX: 00007ffe785435e0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe7854364c R08: 0000000000000000 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000097
R13: 00000000000927c0 R14: 000000000004933d R15: 00007ffe785436a0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g51945 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=16758
rcu: rcu_preempt kthread starved for 10502 jiffies! g51945 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:26712 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 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: 9820 Comm: syz-executor Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__remove_hrtimer kernel/time/hrtimer.c:1117 [inline]
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1668 [inline]
RIP: 0010:__hrtimer_run_queues+0x3e1/0xcf0 kernel/time/hrtimer.c:1752
Code: 00 00 c6 02 00 80 e3 01 0f b6 db 31 ff 89 de e8 d5 ff 10 00 84 db 75 0a e8 6c fd 10 00 e9 86 00 00 00 48 8b bc 24 88 00 00 00 <4c> 89 f6 e8 07 3c c9 02 84 c0 74 07 e8 4e fd 10 00 eb 6b 48 8b 9c
RSP: 0018:ffffc90000007d60 EFLAGS: 00000002
RAX: 0000000000010000 RBX: 0000000000000001 RCX: ffff888026389dc0
RDX: ffff888026389dc0 RSI: 0000000000000001 RDI: ffff8880b8e2a350
RBP: ffffc90000007ea8 R08: ffffffff816f881b R09: fffffbfff1c150ee
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b8e2a200
R13: ffff8880b8e2a200 R14: ffff88807c0dbb40 R15: dffffc0000000000
FS:  00005555746ec500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555746ec808 CR3: 000000005078c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 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_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 42 80 81 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e7 9e 0e f7 65 8b 05 f8 81 b9 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90002eafba0 EFLAGS: 00000206
RAX: 8fcb2aa0f745b900 RBX: 1ffff920005d5f78 RCX: ffffffff96a92f03
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: ffffc90002eafc30 R08: ffffffff81870420 R09: ffffed10171c5441
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff920005d5f74 R14: ffffc90002eafbc0 R15: 0000000000000246
 hrtimer_start_expires include/linux/hrtimer.h:434 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1968 [inline]
 do_nanosleep+0x164/0x7b0 kernel/time/hrtimer.c:2044
 hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2100
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1313 [inline]
 __se_sys_clock_nanosleep+0x323/0x3b0 kernel/time/posix-timers.c:1290
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ffaf4338a25
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007ffe785435a0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000142 RCX: 00007ffaf4338a25
RDX: 00007ffe785435e0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe7854364c R08: 0000000000000000 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000097
R13: 00000000000927c0 R14: 000000000004933d R15: 00007ffe785436a0
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/12 01:54 linux-5.15.y c16c81c81336 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_nanosleep
2025/01/22 19:59 linux-5.15.y 4735586da88e a44b0418 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_nanosleep
* Struck through repros no longer work on HEAD.