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INFO: rcu detected stall in schedule (2)

Status: closed as invalid on 2019/12/04 14:04
Subsystems: kernel
[Documentation on labels]
First crash: 1606d, last: 1605d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in schedule (5) kernel 1 1055d 1055d 0/26 auto-closed as invalid on 2021/09/03 22:50
upstream INFO: rcu detected stall in schedule (4) cgroups mm 2 1569d 1569d 0/26 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in schedule (3) mm cgroups 4 1570d 1570d 0/26 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in schedule kernel 1 1949d 1944d 0/26 auto-closed as invalid on 2019/06/23 09:16
upstream INFO: rcu detected stall in schedule (6) kernel syz done 1 256d 253d 0/26 auto-obsoleted due to no activity on 2023/11/21 16:15

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=3ea/1/0x4000000000000002 softirq=13396/13398 fqs=36 
	(t=10500 jiffies g=6869 q=151)
rcu: rcu_preempt kthread starved for 10422 jiffies! g6869 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29032    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8373 Comm: syz-executor.1 Not tainted 5.4.0-syzkaller #0
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+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 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:2827 [inline]
 rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:mod_memcg_page_state+0xe/0x190 include/linux/memcontrol.h:652
Code: 00 eb 05 e8 04 29 2e 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 54 53 41 89 f6 <48> 89 fb e8 da 28 2e 00 48 83 c3 38 48 89 d8 48 c1 e8 03 49 bc 00
RSP: 0018:ffffc900021a7d10 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff110129d1981 RBX: ffff888094e8cc08 RCX: 0000000000000000
RDX: ffffc90005129000 RSI: 00000000fffffffc RDI: ffffea00029e5440
RBP: ffffc900021a7d30 R08: 000000000003a768 R09: ffffed10131812c7
R10: ffffed10131812c7 R11: 0000000000000000 R12: ffff888094e8cca0
R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff888098c09628
 free_thread_stack+0x168/0x590 kernel/fork.c:280
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 exit_to_usermode_loop arch/x86/entry/common.c:150 [inline]
 prepare_exit_to_usermode+0x2d4/0x5b0 arch/x86/entry/common.c:195
 ret_from_intr+0x26/0x36
RIP: 0033:0x4045f7
Code: 25 28 00 00 00 48 89 44 24 28 31 c0 84 d2 75 3e 8b 3f 40 0f b6 de be 64 63 00 00 89 da e8 f1 5e 05 00 85 c0 0f 85 a2 00 00 00 <64> 48 89 2c 25 00 ff ff ff 48 8b 44 24 28 64 48 33 04 25 28 00 00
RSP: 002b:00007f5d2d9b3cb0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045a4e7
RDX: 0000000000000000 RSI: 0000000000006364 RDI: 00000000000000e8
RBP: 000000000075bfa8 R08: 00007f5d2d9b4700 R09: 00007f5d2d9b4700
R10: 00007f5d2d9b49d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd941db58f R14: 00007f5d2d9b49c0 R15: 000000000075bf2c

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/03 23:33 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 20:41 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 18:21 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 17:27 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 14:28 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 10:42 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 07:10 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:15 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:14 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 03:44 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.