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INFO: rcu detected stall in schedule (3)

Status: closed as invalid on 2020/01/08 05:23
Subsystems: mm cgroups
[Documentation on labels]
First crash: 1899d, last: 1899d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in schedule (5) kernel 1 1384d 1384d 0/28 auto-closed as invalid on 2021/09/03 22:50
upstream INFO: rcu detected stall in schedule (4) cgroups mm 2 1898d 1898d 0/28 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in schedule (2) kernel 10 1934d 1935d 0/28 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in schedule (7) usb C done 49 3d18h 297d 0/28 upstream: reported C repro on 2024/05/27 15:00
upstream INFO: rcu detected stall in schedule kernel 1 2278d 2273d 0/28 auto-closed as invalid on 2019/06/23 09:16
linux-6.1 INFO: rcu detected stall in schedule 4 274d 286d 0/3 auto-obsoleted due to no activity on 2024/09/27 22:30
upstream INFO: rcu detected stall in schedule (6) kernel syz done 1 585d 582d 0/28 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=766/1/0x4000000000000002 softirq=14625/14625 fqs=2726 
	(t=10500 jiffies g=6985 q=227)
rcu: rcu_preempt kthread starved for 5028 jiffies! g6985 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: 8532 Comm: syz-executor.0 Not tainted 5.5.0-rc5-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:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 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:__memcg_kmem_uncharge+0x6/0x1a0 mm/memcontrol.c:2908
Code: bf ac 07 00 74 12 48 81 c3 08 02 00 00 48 89 df 4c 89 f6 e8 8c 85 ff ff 5b 41 5e 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 50 89 f3 49 89 fc 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc90002597d28 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffffffff81489244 RBX: ffffea000232c6c0 RCX: ffff88808e6b6580
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea000232c6c0
RBP: ffffc90002597d30 R08: dffffc0000000000 R09: fffffbfff124248a
R10: fffffbfff124248a R11: 0000000000000000 R12: ffff8880a2007c20
R13: dffffc0000000000 R14: 1ffff11014400f84 R15: ffff8880a2331838
 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline]
 free_thread_stack+0x12e/0x590 kernel/fork.c:284
 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: 0033:0x45a537
Code: 44 00 00 b8 21 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad c0 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 50 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8d c0 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffea09dc7a8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045a537
RDX: 0000000000000001 RSI: 000000000071be90 RDI: 00007ffea09dc7f0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000001da1940
R10: 0000000001da1c10 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea09dc7e0 R14: 0000000000000000 R15: 00007ffea09dc7f0

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/08 05:16 upstream ae6088216ce4 6738e0b3 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/08 04:56 upstream ae6088216ce4 6738e0b3 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/08 04:52 upstream ae6088216ce4 6738e0b3 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/08 03:04 upstream ae6088216ce4 6738e0b3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.