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INFO: rcu detected stall in newfstatat (2)

Status: auto-closed as invalid on 2022/08/20 09:41
Subsystems: kernfs
[Documentation on labels]
First crash: 728d, last: 693d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in newfstatat (3) usb C done 30 39d 309d 0/26 upstream: reported C repro on 2023/06/10 09:07
upstream INFO: rcu detected stall in newfstatat fs 2 823d 839d 0/26 closed as invalid on 2022/02/08 09:50

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=589/1/0x4000000000000000 softirq=30665/30666 fqs=1 
	(detected by 1, t=10502 jiffies, g=46537, q=111)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 2967 Comm: udevd Not tainted 5.18.0-rc7-syzkaller-00181-geaea45fc0e7b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:lock_is_held_type+0x106/0x140 kernel/locking/lockdep.c:5689
Code: 65 0f c1 05 34 65 95 76 83 f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 44 89 e8 5b 5d 41 5c <41> 5d 41 5e 41 5f c3 45 31 ed eb b9 0f 0b 48 c7 c7 20 44 cc 89 e8
RSP: 0018:ffffc90000007c18 EFLAGS: 00000096
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000010003 RDI: 0000000000000000
RBP: 1ffff92000000f8b R08: 0000000000000000 R09: ffffffff8db8eb17
R10: fffffbfff1b71d62 R11: 0000000000000001 R12: 0000000000000001
R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88807c37acb0
FS:  00007f9ad60fe840(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9786fa0000 CR3: 000000007c006000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_is_held include/linux/lockdep.h:283 [inline]
 rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0x522/0x720 kernel/locking/lockdep.c:5652
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194
 debug_object_activate+0x287/0x3e0 lib/debugobjects.c:689
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:475 [inline]
 enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1702 [inline]
 __hrtimer_run_queues+0xb02/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:kasan_check_range+0x16/0x180 mm/kasan/generic.c:188
Code: ff ff 89 43 08 5b 5d c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 48 85 f6 0f 84 3c 01 00 00 49 89 f9 41 54 44 0f b6 c2 49 01 f1 55 <53> 0f 82 18 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 48 39 c7 0f 86
RSP: 0018:ffffc9000304f768 EFLAGS: 00000292
RAX: 0000000000000000 RBX: ffff888011e11cd8 RCX: ffffffff896f7665
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888011e11cd8
RBP: ffff888140f17740 R08: 0000000000000001 R09: ffff888011e11ce0
R10: fffffbfff200e521 R11: 0000000000000001 R12: 1ffff92000609ef2
R13: dffffc0000000000 R14: ffff888011e11cd8 R15: ffffc9000304fba0
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_long_add_return_acquire include/linux/atomic/atomic-instrumented.h:1309 [inline]
 rwsem_read_trylock kernel/locking/rwsem.c:237 [inline]
 __down_read_common kernel/locking/rwsem.c:1213 [inline]
 __down_read kernel/locking/rwsem.c:1223 [inline]
 down_read+0xa5/0x440 kernel/locking/rwsem.c:1463
 kernfs_dop_revalidate+0xec/0x600 fs/kernfs/dir.c:1091
 d_revalidate fs/namei.c:854 [inline]
 d_revalidate fs/namei.c:851 [inline]
 lookup_fast+0x385/0x6d0 fs/namei.c:1668
 walk_component+0xcf/0x6a0 fs/namei.c:2016
 link_path_walk.part.0+0x7ef/0xf70 fs/namei.c:2347
 link_path_walk fs/namei.c:2271 [inline]
 path_lookupat+0xc8/0x860 fs/namei.c:2498
 filename_lookup+0x1c6/0x590 fs/namei.c:2528
 vfs_statx+0x148/0x390 fs/stat.c:228
 vfs_fstatat+0x8c/0xb0 fs/stat.c:255
 __do_sys_newfstatat+0x91/0x110 fs/stat.c:425
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9ad5d251da
Code: 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 0b 00 00 00 66 2e 0f 1f 84 00 00 00 00 00 90 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 69 fc 0c 00 f7
RSP: 002b:00007ffc72ce4858 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffc72ce5418 RCX: 00007f9ad5d251da
RDX: 00007ffc72ce4868 RSI: 00007ffc72ce4cf8 RDI: 00000000ffffff9c
RBP: 00007ffc72ce48f8 R08: 0000000000000000 R09: 000055cee848e060
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc72ce4cf8
R13: 00007ffc72ce4868 R14: 000055cee84572c0 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g46537 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28944 pid:   16 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5073 [inline]
 __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6388
 schedule+0xd2/0x1f0 kernel/sched/core.c:6460
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1971
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2144
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 45 Comm: kworker/u4:2 Not tainted 5.18.0-rc7-syzkaller-00181-geaea45fc0e7b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound toggle_allocation_gate
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:490
 print_other_cpu_stall kernel/rcu/tree_stall.h:595 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:741 [inline]
 rcu_pending kernel/rcu/tree.c:3923 [inline]
 rcu_sched_clock_irq+0x1f7c/0x2150 kernel/rcu/tree.c:2625
 update_process_times+0x16d/0x200 kernel/time/timer.c:1788
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243
 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:csd_lock_wait kernel/smp.c:411 [inline]
RIP: 0010:smp_call_function_many_cond+0x499/0x1110 kernel/smp.c:969
Code: 01 89 ee e8 99 d2 0b 00 85 ed 74 47 48 8b 04 24 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 fc 83 c5 03 e8 59 d0 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 21 0a 00 00 8b 43 08 31
RSP: 0018:ffffc90000d6f950 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b9c44fc0 RCX: 0000000000000000
RDX: ffff888018438180 RSI: ffffffff816ca537 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff816ca55d R11: 0000000000000000 R12: ffffed10173889f9
R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000
 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1135
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1184 [inline]
 text_poke_bp_batch+0x22c/0x6b0 arch/x86/kernel/alternative.c:1372
 text_poke_flush arch/x86/kernel/alternative.c:1542 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:1539 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1549
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x32f/0x410 kernel/jump_label.c:830
 static_key_enable_cpuslocked+0x1b1/0x260 kernel/jump_label.c:177
 static_key_enable+0x16/0x20 kernel/jump_label.c:190
 toggle_allocation_gate mm/kfence/core.c:774 [inline]
 toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:766
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
----------------
Code disassembly (best guess):
   0:	65 0f c1 05 34 65 95 	xadd   %eax,%gs:0x76956534(%rip)        # 0x7695653c
   7:	76
   8:	83 f8 01             	cmp    $0x1,%eax
   b:	75 29                	jne    0x36
   d:	9c                   	pushfq
   e:	58                   	pop    %rax
   f:	f6 c4 02             	test   $0x2,%ah
  12:	75 3d                	jne    0x51
  14:	48 f7 04 24 00 02 00 	testq  $0x200,(%rsp)
  1b:	00
  1c:	74 01                	je     0x1f
  1e:	fb                   	sti
  1f:	48 83 c4 08          	add    $0x8,%rsp
  23:	44 89 e8             	mov    %r13d,%eax
  26:	5b                   	pop    %rbx
  27:	5d                   	pop    %rbp
  28:	41 5c                	pop    %r12
* 2a:	41 5d                	pop    %r13 <-- trapping instruction
  2c:	41 5e                	pop    %r14
  2e:	41 5f                	pop    %r15
  30:	c3                   	retq
  31:	45 31 ed             	xor    %r13d,%r13d
  34:	eb b9                	jmp    0xffffffef
  36:	0f 0b                	ud2
  38:	48 c7 c7 20 44 cc 89 	mov    $0xffffffff89cc4420,%rdi
  3f:	e8                   	.byte 0xe8

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/05/22 09:34 upstream eaea45fc0e7b 7268fa62 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in newfstatat
2022/04/17 21:02 upstream a2c29ccd9477 8bcc32a6 .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in newfstatat
* Struck through repros no longer work on HEAD.