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INFO: rcu detected stall in ext4_file_write_iter (4)

Status: closed as invalid on 2022/02/08 10:32
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+03464269af631f4a4bdf@syzkaller.appspotmail.com
First crash: 1109d, last: 1040d
Cause bisection: introduced by (bisect log) [no-op commit]:
commit 38f703663d4c82ead5b51b8860deeef19d6dcb6d
Author: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue Jul 27 10:32:51 2021 +0000

  KVM: arm64: Count VMID-wide TLB invalidations

Crash: INFO: rcu detected stall in corrupted (log)
Repro: C syz .config
  
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
Re: [syzbot] INFO: rcu detected stall in ext4_file_write_iter (4) 1 (1) 2022/02/08 10:32
Re: [syzbot] INFO: rcu detected stall in ext4_file_write_iter (4) 2 (2) 2021/12/29 21:29
[syzbot] INFO: rcu detected stall in ext4_file_write_iter (4) 0 (1) 2021/12/22 17:33
▶ ▼ Similar bugs (15)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_file_write_iter (8) mm 3 347d 402d 0/28 auto-obsoleted due to no activity on 2024/03/14 12:59
linux-5.15 INFO: rcu detected stall in ext4_file_write_iter 1 370d 370d 0/3 auto-obsoleted due to no activity on 2024/02/29 20:44
upstream INFO: rcu detected stall in ext4_file_write_iter (3) block 5 1205d 1294d 0/28 auto-closed as invalid on 2021/11/07 19:52
upstream INFO: rcu detected stall in ext4_file_write_iter (5) mm 3 945d 945d 0/28 auto-closed as invalid on 2022/06/25 07:58
linux-6.1 INFO: rcu detected stall in ext4_file_write_iter 1 239d 239d 0/3 auto-obsoleted due to no activity on 2024/07/10 06:27
upstream INFO: rcu detected stall in ext4_file_write_iter (7) mm bpf ext4 3 453d 495d 23/28 fixed on 2023/10/12 12:47
android-49 INFO: rcu detected stall in ext4_file_write_iter syz 2 2003d 2044d 0/3 public: reported syz repro on 2019/04/23 08:58
upstream INFO: rcu detected stall in ext4_file_write_iter (2) ext4 1 1506d 1506d 0/28 auto-closed as invalid on 2021/01/10 12:58
linux-4.14 INFO: rcu detected stall in ext4_file_write_iter C 7 646d 2055d 0/1 upstream: reported C repro on 2019/04/12 16:30
upstream INFO: rcu detected stall in ext4_file_write_iter C inconclusive done 93 1568d 2100d 15/28 fixed on 2020/09/25 01:17
linux-4.19 INFO: rcu detected stall in ext4_file_write_iter C error 9 706d 2047d 0/1 upstream: reported C repro on 2019/04/20 13:09
upstream INFO: rcu detected stall in ext4_file_write_iter (6) ext4 C error 8 594d 657d 22/28 fixed on 2023/06/08 14:41
upstream INFO: rcu detected stall in ext4_file_write_iter (9) mm 8 163d 227d 0/28 auto-obsoleted due to no activity on 2024/09/14 13:24
linux-4.19 BUG: soft lockup in ext4_file_write_iter 1 1250d 1250d 0/1 auto-closed as invalid on 2021/10/22 22:26
android-5-15 BUG: soft lockup in ext4_file_write_iter 6 168d 234d 0/2 auto-obsoleted due to no activity on 2024/09/09 02:51

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 1, t=10502 jiffies, g=5077, q=32)
rcu: All QSes seen, last rcu_preempt kthread activity 3349 (4295002251-4294998902), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 3350 jiffies! g5077 f0x2 RCU_GP_CLEANUP(7) ->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:26576 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xb72/0x1460 kernel/sched/core.c:6253
 preempt_schedule_common kernel/sched/core.c:6419 [inline]
 preempt_schedule+0x14d/0x190 kernel/sched/core.c:6444
 preempt_schedule_thunk+0x16/0x18
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
 rcu_gp_cleanup+0x4f4/0xbc0 kernel/rcu/tree.c:2059
 rcu_gp_kthread+0xb3/0x350 kernel/rcu/tree.c:2132
 kthread+0x468/0x490 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 3645 Comm: syz-executor587 Not tainted 5.16.0-rc6-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:88 [inline]
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation+0x1ff/0x270 kernel/rcu/tree_stall.h:481
 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3878 [inline]
 rcu_sched_clock_irq+0x23d5/0x2bc0 kernel/rcu/tree.c:2597
 update_process_times+0x197/0x200 kernel/time/timer.c:1785
 tick_sched_handle kernel/time/tick-sched.c:226 [inline]
 tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0010:unwind_next_frame+0xaa1/0x1fc0
Code: 42 8a 04 30 84 c0 48 8b 5c 24 78 48 8b 6c 24 20 0f 85 e1 11 00 00 c6 03 00 ba 10 00 00 00 48 8b 7c 24 28 31 f6 e8 af b0 95 00 <e9> 66 04 00 00 48 89 5c 24 60 49 8d 7d 08 48 89 f8 48 c1 e8 03 42
RSP: 0018:ffffc900027de900 EFLAGS: 00000202
RAX: ffffc900027dea10 RBX: ffffc900027de9f5 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900027dea20
RBP: ffffffff8e814392 R08: dffffc0000000000 R09: ffffc900027dea10
R10: fffff520004fbd44 R11: 0000000000000000 R12: 1ffffffff1d02872
R13: ffffc900027de9c0 R14: dffffc0000000000 R15: ffffffff8e814396
 arch_stack_walk+0x112/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x11b/0x1e0 kernel/stacktrace.c:122
 save_stack+0xff/0x200 mm/page_owner.c:119
 __set_page_owner+0x42/0x2f0 mm/page_owner.c:181
 prep_new_page mm/page_alloc.c:2418 [inline]
 get_page_from_freelist+0x729/0x9e0 mm/page_alloc.c:4149
 __alloc_pages+0x255/0x580 mm/page_alloc.c:5369
 alloc_slab_page mm/slub.c:1793 [inline]
 allocate_slab+0xcc/0x4d0 mm/slub.c:1930
 new_slab mm/slub.c:1993 [inline]
 ___slab_alloc+0x41e/0xc40 mm/slub.c:3022
 __slab_alloc mm/slub.c:3109 [inline]
 slab_alloc_node mm/slub.c:3200 [inline]
 slab_alloc mm/slub.c:3242 [inline]
 kmem_cache_alloc+0x276/0x310 mm/slub.c:3247
 kmem_cache_zalloc include/linux/slab.h:714 [inline]
 alloc_buffer_head+0x20/0xf0 fs/buffer.c:3309
 alloc_page_buffers+0x309/0x5a0 fs/buffer.c:832
 create_empty_buffers+0x36/0x640 fs/buffer.c:1560
 ext4_block_write_begin+0x300/0x1840 fs/ext4/inode.c:1060
 ext4_da_write_begin+0x58c/0x9b0 fs/ext4/inode.c:2966
 generic_perform_write+0x2dd/0x600 mm/filemap.c:3754
 ext4_buffered_write_iter+0x391/0x520 fs/ext4/file.c:269
 ext4_file_write_iter+0x8f7/0x1bd0
 do_iter_readv_writev+0x54f/0x740
 do_iter_write+0x21e/0x7b0 fs/read_write.c:851
 iter_file_splice_write+0x7eb/0xfa0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0xe6/0x1c0 fs/splice.c:936
 splice_direct_to_actor+0x529/0xd00 fs/splice.c:891
 do_splice_direct+0x291/0x3e0 fs/splice.c:979
 do_sendfile+0x6fe/0x1040 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64+0x171/0x1d0 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f364932b0a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd55ee2f98 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f364932b0a9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 00008400fffffffa R11: 0000000000000246 R12: 00007f36492ee880
R13: 0000000000000000 R14: 00007ffd55ee2fc0 R15: 00007ffd55ee2fb0
 </TASK>
sched: RT throttling activated
----------------
Code disassembly (best guess):
   0:	42 8a 04 30          	mov    (%rax,%r14,1),%al
   4:	84 c0                	test   %al,%al
   6:	48 8b 5c 24 78       	mov    0x78(%rsp),%rbx
   b:	48 8b 6c 24 20       	mov    0x20(%rsp),%rbp
  10:	0f 85 e1 11 00 00    	jne    0x11f7
  16:	c6 03 00             	movb   $0x0,(%rbx)
  19:	ba 10 00 00 00       	mov    $0x10,%edx
  1e:	48 8b 7c 24 28       	mov    0x28(%rsp),%rdi
  23:	31 f6                	xor    %esi,%esi
  25:	e8 af b0 95 00       	callq  0x95b0d9
* 2a:	e9 66 04 00 00       	jmpq   0x495 <-- trapping instruction
  2f:	48 89 5c 24 60       	mov    %rbx,0x60(%rsp)
  34:	49 8d 7d 08          	lea    0x8(%r13),%rdi
  38:	48 89 f8             	mov    %rdi,%rax
  3b:	48 c1 e8 03          	shr    $0x3,%rax
  3f:	42                   	rex.X

Crashes (58):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/24 04:24 upstream 76657eaef4a7 6caa12e4 .config console log report syz C ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/18 17:25 upstream 9eaa88c7036e 44068e19 .config console log report syz C ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2022/01/21 00:34 upstream fa2e1ba3e9e3 b838eb76 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2022/01/20 01:13 upstream 1d1df41c5a33 5da9499f .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2022/01/06 05:27 upstream 49ef78e59b07 6acc789a .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2022/01/02 00:47 upstream 278218f6778b e1768e9c .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/31 15:40 upstream 4f3d93c6eaff 36bd2e48 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/31 14:20 upstream 4f3d93c6eaff 36bd2e48 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/31 03:23 upstream 74c78b4291b4 36bd2e48 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/31 03:21 upstream 74c78b4291b4 36bd2e48 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 23:07 upstream ecf71de775a0 76c8cf06 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 20:21 upstream a8ad9a2434dc 76c8cf06 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 18:42 upstream a8ad9a2434dc 76c8cf06 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 17:30 upstream a8ad9a2434dc 76c8cf06 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 10:10 upstream a8ad9a2434dc 6b3c5e64 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/25 22:11 upstream e2ae0d4a6b0b 6caa12e4 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/24 14:09 upstream 7a29b11da965 6caa12e4 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/24 01:10 upstream 76657eaef4a7 6caa12e4 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/23 06:16 upstream 3f066e882bf1 6caa12e4 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/23 06:09 upstream 3f066e882bf1 6caa12e4 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/22 02:27 upstream 2f47a9a4dfa3 6caa12e4 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/22 01:43 upstream 2f47a9a4dfa3 6caa12e4 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/21 18:23 upstream 6e0567b73052 a938f0b8 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/21 18:04 upstream 6e0567b73052 a938f0b8 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/21 17:51 upstream 6e0567b73052 a938f0b8 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/21 17:51 upstream 6e0567b73052 a938f0b8 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/18 13:21 upstream 9eaa88c7036e 44068e19 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/14 15:15 upstream 5472f14a3742 d018dd31 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/12 03:49 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/12 03:39 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/12 03:29 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/12 03:29 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/09 16:59 upstream 2a987e65025e b54aa474 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/08 16:33 upstream 2a987e65025e a4a2a501 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/07 18:53 upstream cd8c917a56f2 0230ba3e .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2021/11/13 00:26 upstream 7246f4dcaccc 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/11/22 04:42 bpf c0d95d3380ee 4eb20a4e .config console log report info ci-upstream-bpf-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
2022/01/18 13:59 net-next-old fe8152b38d3a 731a2d23 .config console log report info ci-upstream-net-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
2022/01/12 23:10 bpf-next 775a64e3845c 44d1319a .config console log report info ci-upstream-bpf-next-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
2022/01/11 23:34 bpf-next 775a64e3845c 44d1319a .config console log report info ci-upstream-bpf-next-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
2022/01/04 04:25 net-next-old 7590fc6f80ac 7f723fbe .config console log report info ci-upstream-net-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
2021/12/31 08:39 linux-next ea586a076e8a 36bd2e48 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 23:01 linux-next ea586a076e8a 76c8cf06 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 22:34 linux-next ea586a076e8a 76c8cf06 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/28 10:19 linux-next ea586a076e8a 6b3c5e64 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/23 16:27 linux-next 79f063d60c8c 6caa12e4 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/22 17:31 linux-next 2bd48302750c 6caa12e4 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/21 17:44 linux-next 07f8c60fe60f a938f0b8 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/21 17:43 linux-next 07f8c60fe60f a938f0b8 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
2021/12/15 12:24 linux-next ea922272cbe5 f752fb53 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in ext4_file_write_iter
* Struck through repros no longer work on HEAD.