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INFO: rcu detected stall in kernfs_fop_write

Status: closed as invalid on 2019/12/04 14:14
Subsystems: kernel
[Documentation on labels]
First crash: 1884d, last: 1882d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in kernfs_fop_write (3) kernel 1 1627d 1627d 0/28 auto-closed as invalid on 2020/11/13 21:51
upstream INFO: rcu detected stall in kernfs_fop_write (2) kernel 2 1847d 1847d 0/28 closed as invalid on 2020/01/09 08:13

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=8e6/1/0x4000000000000002 softirq=10714/10714 fqs=1 
	(t=10500 jiffies g=6641 q=106)
rcu: rcu_preempt kthread starved for 10497 jiffies! g6641 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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 0
CPU: 0 PID: 8337 Comm: syz-executor.5 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:check_kcov_mode kernel/kcov.c:68 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x14/0x50 kernel/kcov.c:102
Code: 00 00 00 48 8b 3d f4 3c cd 07 48 89 de e8 d4 01 3b 00 5b 5d c3 cc 48 8b 04 24 65 48 8b 0c 25 c0 1d 02 00 65 8b 15 38 84 8b 7e <f7> c2 00 01 1f 00 75 2c 8b 91 80 13 00 00 83 fa 02 75 21 48 8b 91
RSP: 0018:ffffc90002747250 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffffffff81487326 RBX: ffffea00024588c0 RCX: ffff888092ab4100
RDX: 0000000000000001 RSI: 00000000fffffffc RDI: ffffea00024588c0
RBP: ffffc90002747278 R08: 000000000003a728 R09: fffffbfff120248a
R10: fffffbfff120248a R11: 0000000000000000 R12: ffff88808aa659a0
R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff8880988217e8
 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
 preempt_schedule_irq+0xc1/0x140 kernel/sched/core.c:4338
 retint_kernel+0x1b/0x2b
RIP: 0010:batadv_hardif_get_by_netdev+0x105/0x3f0 net/batman-adv/hard-interface.c:72
Code: e8 03 48 89 45 c0 49 c7 c5 78 70 dd 8a 4c 89 65 b8 eb 07 66 90 e8 bb 35 a4 f9 49 8d 5f 18 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 21 ab df f9 4c 39 23 74 0c e8 97 35 a4 f9 e9 58
RSP: 0018:ffffc900027474d8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02
RAX: 1ffff1100ebe9003 RBX: ffff888075f48018 RCX: ffff888092ab4100
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880aed37e20
RBP: ffffc90002747520 R08: dffffc0000000000 R09: ffffed1015da6fc5
R10: ffffed1015da6fc5 R11: 0000000000000000 R12: ffff8880902d8000
R13: ffffffff8add7078 R14: dffffc0000000000 R15: ffff888075f48000
 batadv_hard_if_event+0x89/0xf10 net/batman-adv/hard-interface.c:1031
 notifier_call_chain kernel/notifier.c:95 [inline]
 __raw_notifier_call_chain kernel/notifier.c:396 [inline]
 raw_notifier_call_chain+0xec/0x190 kernel/notifier.c:403
 call_netdevice_notifiers_info net/core/dev.c:1893 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:1905 [inline]
 call_netdevice_notifiers net/core/dev.c:1919 [inline]
 register_netdevice+0xf70/0x1830 net/core/dev.c:9310
 nsim_create+0x1d4/0x230 drivers/net/netdevsim/netdev.c:309
 __nsim_dev_port_add+0x289/0x4d0 drivers/net/netdevsim/dev.c:648
 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:697 [inline]
 nsim_dev_probe+0xb55/0xef0 drivers/net/netdevsim/dev.c:818
 nsim_bus_probe+0x15/0x20 drivers/net/netdevsim/bus.c:242
 really_probe+0x71c/0xf40 drivers/base/dd.c:548
 driver_probe_device+0xfc/0x260 drivers/base/dd.c:721
 __device_attach_driver+0x336/0x3f0 drivers/base/dd.c:828
 bus_for_each_drv+0x12b/0x180 drivers/base/bus.c:430
 __device_attach+0x1ea/0x390 drivers/base/dd.c:894
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:941
 bus_probe_device+0xb9/0x1f0 drivers/base/bus.c:490
 device_add+0x1710/0x1ad0 drivers/base/core.c:2487
 device_register+0x1d/0x20 drivers/base/core.c:2560
 nsim_bus_dev_new drivers/net/netdevsim/bus.c:288 [inline]
 new_device_store+0x286/0x510 drivers/net/netdevsim/bus.c:182
 bus_attr_store+0x78/0x90 drivers/base/bus.c:121
 sysfs_kf_write+0x281/0x2f0 fs/sysfs/file.c:138
 kernfs_fop_write+0x3e4/0x4e0 fs/kernfs/file.c:315
 __vfs_write+0xb8/0x740 fs/read_write.c:494
 vfs_write+0x275/0x590 fs/read_write.c:558
 ksys_write+0x117/0x220 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:620
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x414130
Code: b0 89 c8 f7 d8 eb ed b8 6e 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 83 3d 3d 43 66 00 00 75 14 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 c4 1b 00 00 c3 48 83 ec 08 e8 ca fc ff ff
RSP: 002b:00007ffcc9191d38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000414130
RDX: 0000000000000003 RSI: 00007ffcc9191d60 RDI: 0000000000000004
RBP: 00007ffcc9191d60 R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000000075 R11: 0000000000000246 R12: 00000000004bfc97
R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/04 11:19 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 10:44 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 05:38 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 05:36 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 04:10 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 03:13 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 02:53 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 00:00 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 23:56 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 18:15 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 17:41 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 15:30 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 15:03 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 14:40 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 14:08 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 10:52 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 07:27 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 07:07 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 02:29 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 20:58 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 20:31 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.