syzbot


INFO: rcu detected stall in sys_clock_settime

Status: upstream: reported on 2023/07/13 03:09
Reported-by: syzbot+b9b138957d968392c98d@syzkaller.appspotmail.com
First crash: 647d, last: 41d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in sys_clock_settime origin:lts-only C done 37 39d 740d 0/3 upstream: reported C repro on 2023/04/11 17:25
upstream INFO: rcu detected stall in sys_clock_settime kernel C done inconclusive 444 11d 1743d 0/28 upstream: reported C repro on 2020/07/12 17:54

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 ticks this GP) idle=d7b/1/0x4000000000000000 softirq=16574/16574 fqs=0 
	(detected by 0, t=10506 jiffies, g=19749, q=1446)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7024 Comm: syz.0.1038 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4724 [inline]
RIP: 0010:__lock_acquire+0x99a/0x1ff0 kernel/locking/lockdep.c:4962
Code: 8e 80 e1 07 80 c1 03 38 c1 0f 8c f8 fe ff ff 48 c7 c7 18 bb 0a 8e e8 05 91 67 00 48 ba 00 00 00 00 00 fc ff df e9 dd fe ff ff <44> 38 7c 24 54 4c 8b 6c 24 30 4c 8b 7c 24 20 4c 8b 64 24 48 76 37
RSP: 0018:ffffc90000dd0a60 EFLAGS: 00000046
RAX: ffff88807b95c668 RBX: 00000000000f4012 RCX: ffff88807b95c670
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff88807b95c654
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff88807b95c668 R14: 1ffff1100f72b8d7 R15: ffff88807b95c602
FS:  00007f1bd89fb6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000000240 CR3: 0000000060374000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1db/0x4f0 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+0x6ce/0x940 net/sched/sch_taprio.c:769
 __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:ffffc900031cfb60 EFLAGS: 00000206
RAX: 3a0245206c282900 RBX: 1ffff92000639f70 RCX: ffffffff81633dd8
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: ffffc900031cfbf0 R08: dffffc0000000000 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000639f6c R14: ffffc900031cfb80 R15: 0000000000000246
 clock_was_set+0x67d/0x880 kernel/time/hrtimer.c:970
 do_settimeofday64+0x673/0x7e0 kernel/time/timekeeping.c:1328
 __do_sys_clock_settime kernel/time/posix-timers.c:1124 [inline]
 __se_sys_clock_settime kernel/time/posix-timers.c:1112 [inline]
 __x64_sys_clock_settime+0x232/0x270 kernel/time/posix-timers.c:1112
 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: 0033:0x7f1bdab92169
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:00007f1bd89fb038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f1bdadaafa0 RCX: 00007f1bdab92169
RDX: 0000000000000000 RSI: 0000400000000240 RDI: 0000000000000000
RBP: 00007f1bdac132a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1bdadaafa0 R15: 00007fff355bfeb8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g19749 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=14670
rcu: rcu_preempt kthread starved for 10506 jiffies! g19749 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
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:27064 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7024 Comm: syz.0.1038 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__kasan_check_read+0x0/0x10 mm/kasan/shadow.c:31
Code: d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c7 37 01 3d 8c eb 0a 48 c7 c7 6f 01 3d 8c 4c 89 fe e8 56 b3 73 08 31 db eb d7 cc cc <89> f6 48 8b 0c 24 31 d2 e9 63 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24
RSP: 0018:ffffc90000dd09d8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8162e2ff
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9098c100
RBP: f273e68c3196d937 R08: dffffc0000000000 R09: fffffbfff2131822
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000002
R13: ffff88807b95c668 R14: ffff88807b95bb80 R15: ffff88807b95c6e0
FS:  00007f1bd89fb6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000000240 CR3: 0000000060374000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <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]
 __lock_acquire+0x1209/0x1ff0 kernel/locking/lockdep.c:5009
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_activate+0x63/0x4e0 lib/debugobjects.c:694
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:475 [inline]
 enqueue_hrtimer+0x30/0x390 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1705 [inline]
 __hrtimer_run_queues+0x6b6/0xcf0 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:ffffc900031cfb60 EFLAGS: 00000206
RAX: 3a0245206c282900 RBX: 1ffff92000639f70 RCX: ffffffff81633dd8
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: ffffc900031cfbf0 R08: dffffc0000000000 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000639f6c R14: ffffc900031cfb80 R15: 0000000000000246
 clock_was_set+0x67d/0x880 kernel/time/hrtimer.c:970
 do_settimeofday64+0x673/0x7e0 kernel/time/timekeeping.c:1328
 __do_sys_clock_settime kernel/time/posix-timers.c:1124 [inline]
 __se_sys_clock_settime kernel/time/posix-timers.c:1112 [inline]
 __x64_sys_clock_settime+0x232/0x270 kernel/time/posix-timers.c:1112
 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: 0033:0x7f1bdab92169
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:00007f1bd89fb038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f1bdadaafa0 RCX: 00007f1bdab92169
RDX: 0000000000000000 RSI: 0000400000000240 RDI: 0000000000000000
RBP: 00007f1bdac132a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1bdadaafa0 R15: 00007fff355bfeb8
 </TASK>

Crashes (32):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/10 20:03 linux-5.15.y c16c81c81336 16256247 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2025/02/18 01:03 linux-5.15.y c16c81c81336 429ea007 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2025/01/22 19:14 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_settime
2025/01/18 05:16 linux-5.15.y 4735586da88e f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/12/17 12:01 linux-5.15.y 963e654022cc f93b2b55 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/12/17 11:59 linux-5.15.y 963e654022cc f93b2b55 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/12/15 00:07 linux-5.15.y 963e654022cc 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/10/11 22:21 linux-5.15.y 3a5928702e71 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/09/26 20:47 linux-5.15.y 3a5928702e71 9314348a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/08/21 20:08 linux-5.15.y fa93fa65db6e db5852f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/07/25 23:15 linux-5.15.y 7c6d66f0266f 3f86dfed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/07/23 14:44 linux-5.15.y 7c6d66f0266f e50e8da5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/07/11 06:12 linux-5.15.y f45bea23c39c c699c2eb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/07/05 09:52 linux-5.15.y f45bea23c39c 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/06/25 22:47 linux-5.15.y 4878aadf2d15 dec8bc94 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/06/15 06:40 linux-5.15.y c61bd26ae81a f429ab00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/06/10 19:39 linux-5.15.y c61bd26ae81a 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/05/31 15:37 linux-5.15.y c61bd26ae81a 0c378259 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/05/29 05:12 linux-5.15.y c61bd26ae81a 34889ee3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/05/24 04:24 linux-5.15.y 83655231580b 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/05/20 20:20 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/05/10 00:57 linux-5.15.y 284087d4f7d5 de979bc2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/04/27 19:09 linux-5.15.y b925f60c6ee7 07b455f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/04/16 00:47 linux-5.15.y fa3df276cd36 b9af7e61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/04/06 12:31 linux-5.15.y 9465fef4ae35 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/03/20 09:53 linux-5.15.y b95c01af2113 a485f239 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2024/03/01 19:52 linux-5.15.y 80efc6265290 83acf9e0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2023/12/14 00:10 linux-5.15.y d0fc081c6241 3222d10c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2023/12/12 03:03 linux-5.15.y 8a1d809b0545 28b24332 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2023/09/08 21:50 linux-5.15.y aff03380bda4 6654cf89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2023/09/08 16:20 linux-5.15.y aff03380bda4 6654cf89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
2023/07/13 03:08 linux-5.15.y d54cfc420586 86081196 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_clock_settime
* Struck through repros no longer work on HEAD.