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INFO: rcu detected stall in sys_futex (2)

Status: auto-closed as invalid on 2019/10/25 14:11
Subsystems: kernel
[Documentation on labels]
First crash: 1853d, last: 1709d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_futex (3) kernel 959 1541d 1590d 0/26 auto-closed as invalid on 2020/03/08 12:44
upstream INFO: rcu detected stall in sys_futex (4) kernel 1 790d 790d 0/26 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in sys_futex kernel 1 1915d 1915d 0/26 closed as invalid on 2018/12/31 04:10
linux-5.15 INFO: rcu detected stall in sys_futex 4 87d 261d 0/3 upstream: reported on 2023/07/11 05:38
linux-6.1 INFO: rcu detected stall in sys_futex 5 13h28m 267d 0/3 upstream: reported on 2023/07/05 11:35
upstream INFO: rcu detected stall in sys_futex (5) kernel 12 521d 766d 0/26 auto-obsoleted due to no activity on 2023/02/12 18:33
upstream INFO: rcu detected stall in sys_futex (6) kernel 10 90d 325d 0/26 auto-obsoleted due to no activity on 2024/03/29 00:57

Sample crash report:
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 	1-...!: (1 ticks this GP) idle=f9e/1/0x4000000000000002 softirq=304110/304110 fqs=0 
	(t=11110 jiffies g=515585 q=246)
rcu: rcu_sched kthread starved for 11110 jiffies! g515585 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_sched       I28872    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x772/0x1530 kernel/sched/core.c:3880
 schedule+0xa5/0x260 kernel/sched/core.c:3944
 schedule_timeout+0x44e/0xbc0 kernel/time/timer.c:1807
 rcu_gp_fqs_loop kernel/rcu/tree.c:1611 [inline]
 rcu_gp_kthread+0x835/0x1320 kernel/rcu/tree.c:1768
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8994 Comm: syz-fuzzer Not tainted 5.2.0+ #71
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x16f/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x22d/0x25c lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2736 [inline]
 rcu_sched_clock_irq.cold+0x491/0x8c0 kernel/rcu/tree.c:2183
 update_process_times+0x32/0x80 kernel/time/timer.c:1639
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1296
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x364/0xd90 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x2ea/0x730 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1068 [inline]
 smp_apic_timer_interrupt+0x10b/0x550 arch/x86/kernel/apic/apic.c:1093
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828
 </IRQ>
RIP: 0010:__preempt_count_sub arch/x86/include/asm/preempt.h:84 [inline]
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x54/0x70 kernel/locking/spinlock.c:199
Code: c0 a0 e3 d2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 1e 48 83 3d d5 65 a0 01 00 74 12 fb 66 0f 1f 44 00 00 <65> ff 0d ad 7f cf 78 41 5c 5d c3 0f 0b 48 c7 c7 a0 e3 d2 88 e8 d3
RSP: 0018:ffff8880a499f848 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a5c74 RBX: ffff88808cc74380 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff88808cc74bcc
RBP: ffff8880a499f850 R08: ffff88808cc74380 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880ae935380
R13: ffff8880a98cc340 R14: ffff8880a1e0c580 R15: 0000000000000000
 finish_lock_switch kernel/sched/core.c:3004 [inline]
 finish_task_switch+0x11d/0x690 kernel/sched/core.c:3104
 context_switch kernel/sched/core.c:3257 [inline]
 __schedule+0x77a/0x1530 kernel/sched/core.c:3880
 schedule+0xa5/0x260 kernel/sched/core.c:3944
 freezable_schedule include/linux/freezer.h:172 [inline]
 futex_wait_queue_me+0x30c/0x600 kernel/futex.c:2629
 futex_wait+0x228/0x5e0 kernel/futex.c:2735
 do_futex+0x175/0x1dd0 kernel/futex.c:3646
 __do_sys_futex kernel/futex.c:3707 [inline]
 __se_sys_futex kernel/futex.c:3675 [inline]
 __x64_sys_futex+0x3f7/0x590 kernel/futex.c:3675
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45ddf3
Code: cc cc cc cc cc cc cc 48 8b 7c 24 08 8b 74 24 10 8b 54 24 14 4c 8b 54 24 18 4c 8b 44 24 20 44 8b 4c 24 28 b8 ca 00 00 00 0f 05 <89> 44 24 30 c3 cc cc cc cc cc cc cc cc 8b 7c 24 08 48 8b 74 24 10
RSP: 002b:000000c420037e80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045ddf3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000017c4b18
RBP: 000000c420037ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 000000c420037eb8 R11: 0000000000000246 R12: 0000000000430120
R13: 00000000000000f1 R14: 0000000000000011 R15: 0000000000000000

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/07/24 12:00 upstream c6dd78fcb8ee 32329ceb .config console log report ci-upstream-kasan-gce-root
2019/06/18 06:32 upstream 9e0babf2c06c 442206d7 .config console log report ci-upstream-kasan-gce
2019/04/29 18:25 upstream 37624b58542f b617407b .config console log report ci-upstream-kasan-gce-smack-root
2019/04/16 20:29 upstream b5de3c5026f5 505ab413 .config console log report ci-upstream-kasan-gce-root
2019/03/02 06:41 upstream a215ce8f0e00 1c0e457a .config console log report ci-upstream-kasan-gce-smack-root
2019/04/11 20:53 linux-next 2f4c4d833153 13030ef8 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.