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INFO: rcu detected stall in kernfs_fop_write (3)

Status: auto-closed as invalid on 2020/11/13 21:51
Subsystems: kernel
[Documentation on labels]
First crash: 1342d, last: 1342d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in kernfs_fop_write (2) kernel 2 1562d 1562d 0/26 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in kernfs_fop_write kernel 21 1597d 1599d 0/26 closed as invalid on 2019/12/04 14:14

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (2 ticks this GP) idle=026/1/0x4000000000000000 softirq=121678/121678 fqs=0 
	(detected by 1, t=10502 jiffies, g=236597, q=216)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3905 Comm: systemd-udevd Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:match_held_lock+0x0/0x170 kernel/locking/lockdep.c:4485
Code: ce 8b 05 8b a2 c0 02 85 c0 75 c4 48 c7 c6 00 a5 4b 88 48 c7 c7 40 a5 4b 88 e8 ce c2 53 f9 0f 0b 5b c3 c3 0f 1f 80 00 00 00 00 <48> 39 77 10 0f 84 99 00 00 00 66 f7 47 22 f0 ff 74 4f 55 53 48 83
RSP: 0018:ffffc90000007da0 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81648fff
RDX: dffffc0000000000 RSI: ffff8880ae627758 RDI: ffff8880a069ca10
RBP: ffff8880a069c140 R08: 0000000000000000 R09: ffffffff8ab1fd4f
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880ae627758
R13: ffff8880a069ca10 R14: ffff8880a069ca10 R15: 0000000000000082
FS:  00007f37e4d5c8c0(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560e09360738 CR3: 00000000a05f2000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __lock_is_held kernel/locking/lockdep.c:4779 [inline]
 lock_is_held_type+0x72/0xf0 kernel/locking/lockdep.c:5042
 lock_is_held include/linux/lockdep.h:267 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1490 [inline]
 __hrtimer_run_queues+0xa52/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_apic_timer_interrupt+0xb2/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline]
RIP: 0010:kmem_cache_free.part.0+0x8c/0x1f0 mm/slab.c:3694
Code: e8 99 25 00 00 84 c0 74 76 41 f7 c4 00 02 00 00 74 4e e8 b7 fe c5 ff 48 83 3d 17 20 02 08 00 0f 84 2f 01 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 4c 8b 64 24 20 0f 1f 44 00 00 65 8b 05 ce 7e 4d 7e
RSP: 0018:ffffc90005587bc8 EFLAGS: 00000282
RAX: 0000000001d332bb RBX: ffff888097c7d900 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff8880a9051d00 R08: 0000000000000001 R09: ffffffff8c5eda3f
R10: fffffbfff18bdb47 R11: 0000000000000001 R12: 0000000000000282
R13: ffffffff863510df R14: 0000000000000002 R15: 0000000000000000
 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:622
 __kfree_skb net/core/skbuff.c:679 [inline]
 consume_skb net/core/skbuff.c:837 [inline]
 consume_skb+0xcf/0x160 net/core/skbuff.c:831
 uevent_net_broadcast_untagged lib/kobject_uevent.c:336 [inline]
 kobject_uevent_net_broadcast lib/kobject_uevent.c:408 [inline]
 kobject_uevent_env+0xafb/0x12c0 lib/kobject_uevent.c:592
 kobject_synth_uevent+0x700/0x817 lib/kobject_uevent.c:208
 uevent_store+0x20/0x50 drivers/base/core.c:1980
 dev_attr_store+0x50/0x80 drivers/base/core.c:1683
 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:138
 kernfs_fop_write+0x268/0x490 fs/kernfs/file.c:315
 vfs_write+0x2b0/0x730 fs/read_write.c:576
 ksys_write+0x12d/0x250 fs/read_write.c:631
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f37e3bcf970
Code: 73 01 c3 48 8b 0d 28 d5 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 99 2d 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 7e 9b 01 00 48 89 04 24
RSP: 002b:00007ffff9da2908 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f37e3bcf970
RDX: 0000000000000007 RSI: 0000560e0935d6a0 RDI: 000000000000000e
RBP: 0000560e0935d6a0 R08: 0000560e09360800 R09: 00007f37e4d5c8c0
R10: 0000000000000110 R11: 0000000000000246 R12: 0000000000000007
R13: 0000000000000001 R14: 0000560e09360720 R15: 0000000000000007
rcu: rcu_preempt kthread starved for 10502 jiffies! g236597 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29080    10      2 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1879
 rcu_gp_fqs_loop kernel/rcu/tree.c:1888 [inline]
 rcu_gp_kthread+0xae5/0x1b50 kernel/rcu/tree.c:2058
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/15 21:47 net-next-old 7fca4dee610d 424dd8e7 .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.