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INFO: rcu detected stall in sys_mkdir (2)

Status: closed as invalid on 2019/12/04 14:04
Subsystems: cgroups
[Documentation on labels]
First crash: 1599d, last: 1597d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_mkdir (3) cgroups 1 1563d 1563d 0/26 closed as invalid on 2020/01/08 05:33
upstream INFO: rcu detected stall in sys_mkdir (7) ext4 1 238d 238d 0/26 auto-obsoleted due to no activity on 2023/10/24 07:40
upstream INFO: rcu detected stall in sys_mkdir mm 2 1731d 1732d 0/26 auto-closed as invalid on 2019/10/25 14:21
upstream INFO: rcu detected stall in sys_mkdir (6) ext4 2 809d 818d 0/26 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in sys_mkdir (4) kernel 2 1563d 1562d 0/26 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_mkdir (5) tomoyo 1 945d 945d 0/26 auto-closed as invalid on 2021/12/15 23:48

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=86e/1/0x4000000000000002 softirq=11958/11958 fqs=39 
	(t=10501 jiffies g=6345 q=105)
rcu: rcu_preempt kthread starved for 10424 jiffies! g6345 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29048    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 0
CPU: 0 PID: 8274 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: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:free_thread_stack+0x18b/0x590 kernel/fork.c:284
Code: ff ff e8 28 04 00 00 43 80 3c 2e 00 74 08 4c 89 e7 e8 09 a0 69 00 49 8b 1c 24 48 83 c3 08 48 89 d8 48 c1 e8 03 42 80 3c 28 00 <74> 08 48 89 df e8 eb 9f 69 00 48 8b 1b e9 82 ff ff ff e8 5e 2a 2e
RSP: 0018:ffffc90001f576c8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff11012116bb1 RBX: ffff8880908b5d88 RCX: ffff888094a3a000
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea00025c9f80
RBP: ffffc90001f57700 R08: 000000000003a728 R09: ffffed10140abf17
R10: ffffed10140abf17 R11: 0000000000000000 R12: ffff8880908b5e20
R13: dffffc0000000000 R14: 1ffff11012116bc4 R15: ffff8880a055f8a8
 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
 schedule_timeout+0x46/0x240 kernel/time/timer.c:1871
 do_wait_for_common+0x2e7/0x4d0 kernel/sched/completion.c:83
 __wait_for_common kernel/sched/completion.c:104 [inline]
 wait_for_common kernel/sched/completion.c:115 [inline]
 wait_for_completion+0x47/0x60 kernel/sched/completion.c:136
 __wait_rcu_gp+0x2b1/0x2f0 kernel/rcu/update.c:374
 synchronize_rcu+0xe3/0x100 kernel/rcu/tree.c:2768
 rcu_sync_enter+0x1ae/0x2a0 kernel/rcu/sync.c:149
 percpu_down_write+0x30/0x3c0 kernel/locking/percpu-rwsem.c:146
 cpuset_css_online+0x59/0x7e0 kernel/cgroup/cpuset.c:2733
 online_css+0xbb/0x230 kernel/cgroup/cgroup.c:5047
 css_create kernel/cgroup/cgroup.c:5118 [inline]
 cgroup_apply_control_enable+0xd46/0x1240 kernel/cgroup/cgroup.c:3064
 cgroup_mkdir+0xeb8/0x1280 kernel/cgroup/cgroup.c:5327
 kernfs_iop_mkdir+0x133/0x270 fs/kernfs/dir.c:1127
 vfs_mkdir+0x43f/0x610 fs/namei.c:3811
 do_mkdirat+0x1d7/0x320 fs/namei.c:3834
 __do_sys_mkdir fs/namei.c:3850 [inline]
 __se_sys_mkdir fs/namei.c:3848 [inline]
 __x64_sys_mkdir+0x60/0x70 fs/namei.c:3848
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a97
Code: 1f 40 00 b8 5a 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 7d c2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 5d c2 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffecca3d9c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000459a97
RDX: 00007ffecca3da23 RSI: 00000000000001ff RDI: 00007ffecca3da10
RBP: 00000000000000f8 R08: 0000000000000000 R09: 0000000000000013
R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000416180
R13: 00007ffecca3de38 R14: 0000000000000000 R15: 00007ffecca3da10

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/04 10:52 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 17:44 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 14:49 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 08:30 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 00:49 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.