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INFO: task hung in walk_component

Status: auto-closed as invalid on 2019/10/25 08:50
Reported-by: syzbot+c0ac915a755c76bf5334@syzkaller.appspotmail.com
First crash: 1816d, last: 1816d
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in walk_component 1 1139d 1139d 0/1 auto-closed as invalid on 2021/07/04 02:47
upstream INFO: task hung in walk_component (5) fuse C inconclusive 31 3d16h 605d 0/26 upstream: reported C repro on 2022/08/22 12:38
upstream INFO: task hung in walk_component (3) fs 9 858d 1029d 0/26 closed as invalid on 2022/02/07 19:19
linux-4.19 INFO: task hung in walk_component (2) 2 928d 983d 0/1 auto-closed as invalid on 2022/01/31 04:51
upstream INFO: task hung in walk_component (2) fuse 31 1133d 1133d 20/26 fixed on 2021/04/09 19:46
upstream INFO: task hung in walk_component (4) fs 4 769d 792d 0/26 auto-closed as invalid on 2022/06/09 10:18
linux-4.19 INFO: task hung in walk_component (3) f2fs C error 5 475d 624d 0/1 upstream: reported C repro on 2022/08/03 09:11
upstream INFO: task hung in walk_component fuse 1 2106d 2106d 0/26 closed as invalid on 2018/09/05 12:51

Sample crash report:
   Free memory is 1688kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3522) because
   cache 404kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1688kB above reserved
INFO: task cron:1977 blocked for more than 140 seconds.
      Not tainted 4.4.174+ #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
cron            D
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3559) because
   cache 404kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1688kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.4' (1817) because
   cache 404kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1688kB above reserved
 ffff8801d67578d8 25088  1977      1 0x00000000
 ffff8801d67578d8 ffff8801d66dc740 2d46e947e5f41160 ffff8801d66dc740
 0000000000000000 ffff8801d66dd000 ffff8801db71f180 ffff8801db71f1a8
 ffff8801db71e898 ffff8801d7668000 ffff8801d66dc740 ffffed003acea001
Call Trace:
 [<ffffffff82709b79>] schedule+0x99/0x1d0 kernel/sched/core.c:3355
 [<ffffffff8270a333>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3388
 [<ffffffff8270c492>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8270c492>] mutex_lock_nested+0x3c2/0xb80 kernel/locking/mutex.c:621
 [<ffffffff814c12a2>] lookup_slow fs/namei.c:1693 [inline]
 [<ffffffff814c12a2>] walk_component+0x8a2/0x1000 fs/namei.c:1806
 [<ffffffff814c3f5f>] lookup_last fs/namei.c:2178 [inline]
 [<ffffffff814c3f5f>] path_lookupat.isra.0+0x18f/0x3f0 fs/namei.c:2195
 [<ffffffff814cae94>] filename_lookup+0x1a4/0x3b0 fs/namei.c:2229
 [<ffffffff814cb1f3>] user_path_at_empty+0x43/0x50 fs/namei.c:2403
 [<ffffffff814a52e6>] user_path_at include/linux/namei.h:52 [inline]
 [<ffffffff814a52e6>] vfs_fstatat+0xc6/0x170 fs/stat.c:106
 [<ffffffff814a64f4>] vfs_stat fs/stat.c:123 [inline]
 [<ffffffff814a64f4>] SYSC_newstat fs/stat.c:270 [inline]
 [<ffffffff814a64f4>] SyS_newstat+0x94/0x100 fs/stat.c:266
 [<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-fuzzer' (2091) because
   cache 404kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3447) because
   cache 404kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3430) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3479) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3572) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3543) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3082) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3530) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
1 lock held by cron/1977:
 #0:  (&type->i_mutex_dir_key#3){+.+.+.}, at: [<ffffffff814c12a2>] lookup_slow fs/namei.c:1693 [inline]
 #0:  (&type->i_mutex_dir_key#3){+.+.+.}, at: [<ffffffff814c12a2>] walk_component+0x8a2/0x1000 fs/namei.c:1806
Sending NMI to all CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 20 Comm: khungtaskd Not tainted 4.4.174+ #4
task: ffff8801da6c2f80 task.stack: ffff8800001c0000
RIP: 0010:[<ffffffff8109b617>]  [<ffffffff8109b617>] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:62 [inline]
RIP: 0010:[<ffffffff8109b617>]  [<ffffffff8109b617>] flat_send_IPI_mask+0xf7/0x1b0 arch/x86/kernel/apic/apic_flat_64.c:69
RSP: 0018:ffff8800001c7c88  EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000c00 RCX: 0000000000000000
RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fc300
RBP: ffff8800001c7cb8 R08: 0000000000000018 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000246
R13: 0000000003000000 R14: ffffffff82e5f2e0 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a1a008 CR3: 00000001c0604000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Stack:
 0000000000000001 ffffffff82e5f2e0 ffffffff831a6ac0 fffffbfff0634c34
 000000000001b6c0 0000000000000008 ffff8800001c7cd8 ffffffff81092bee
 0000000000000008 ffffffff82924260 ffff8800001c7d30 ffffffff81ab8252
Call Trace:
 [<ffffffff81092bee>] nmi_raise_cpu_backtrace+0x5e/0x80 arch/x86/kernel/apic/hw_nmi.c:33
 [<ffffffff81ab8252>] nmi_trigger_all_cpu_backtrace.cold+0xa1/0xae lib/nmi_backtrace.c:85
 [<ffffffff81092ca4>] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 [<ffffffff813b4762>] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline]
 [<ffffffff813b4762>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff813b4762>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff813b4762>] watchdog.cold+0xd3/0xee kernel/hung_task.c:238
 [<ffffffff811342c3>] kthread+0x273/0x310 kernel/kthread.c:211
 [<ffffffff82718fc5>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:537
Code: 00 c3 5f ff 80 e6 10 75 e1 41 c1 e5 18 44 89 2c 25 10 c3 5f ff 44 89 fa 09 da 80 cf 04 41 83 ff 02 0f 44 d3 89 14 25 00 c3 5f ff <41> f7 c4 00 02 00 00 75 1e 4c 89 e7 57 9d 0f 1f 44 00 00 e8 f1 
NMI backtrace for cpu 1
CPU: 1 PID: 3441 Comm: syz-executor.2 Not tainted 4.4.174+ #4
task: ffff8801151217c0 task.stack: ffff8800032c0000
RIP: 0010:[<ffffffff8211e7bc>]  [<ffffffff8211e7bc>] lowmem_scan+0x44c/0xbf0 drivers/staging/android/lowmemorykiller.c:129
RSP: 0018:ffff8800032c75b8  EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff8800375b33c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8211e78d RDI: ffff8800375b2f94
RBP: ffff8800032c7658 R08: ffff88013ebbb758 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8800375b2f80 R14: 000000000000221e R15: 00000000000003e8
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3497) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1672kB above reserved
FS:  00007fe40d3dd700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a19128 CR3: 00000000a33dc000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Stack:
 ffffffff8211e5af ffffffff821122ff ffff8800032c7608 0000000000000246
 ffffffff82ea7320 ffff8801151217c0 0000000000000ea7 ffff8800032c7730
 fffffbfff05c1200 0000223100000600 ffff88013ebbb758 ffff88018f600000
Call Trace:
 [<ffffffff813ee8e2>] do_shrink_slab mm/vmscan.c:357 [inline]
 [<ffffffff813ee8e2>] shrink_slab.part.0+0x402/0xb30 mm/vmscan.c:455
 [<ffffffff813f742c>] shrink_slab mm/vmscan.c:425 [inline]
 [<ffffffff813f742c>] shrink_zone+0x4bc/0x610 mm/vmscan.c:2448
 [<ffffffff813f7bef>] shrink_zones mm/vmscan.c:2603 [inline]
 [<ffffffff813f7bef>] do_try_to_free_pages mm/vmscan.c:2653 [inline]
 [<ffffffff813f7bef>] try_to_free_pages+0x66f/0x1260 mm/vmscan.c:2861
 [<ffffffff813d09af>] __perform_reclaim mm/page_alloc.c:2915 [inline]
 [<ffffffff813d09af>] __alloc_pages_direct_reclaim mm/page_alloc.c:2936 [inline]
 [<ffffffff813d09af>] __alloc_pages_slowpath mm/page_alloc.c:3201 [inline]
 [<ffffffff813d09af>] __alloc_pages_nodemask+0x8af/0x14b0 mm/page_alloc.c:3313
 [<ffffffff813d1cf3>] __alloc_pages include/linux/gfp.h:415 [inline]
 [<ffffffff813d1cf3>] __alloc_pages_node include/linux/gfp.h:428 [inline]
 [<ffffffff813d1cf3>] alloc_pages_node include/linux/gfp.h:442 [inline]
 [<ffffffff813d1cf3>] alloc_kmem_pages_node+0x23/0x30 mm/page_alloc.c:3504
 [<ffffffff810cae87>] alloc_thread_stack_node kernel/fork.c:167 [inline]
 [<ffffffff810cae87>] dup_task_struct kernel/fork.c:353 [inline]
 [<ffffffff810cae87>] copy_process+0x2e7/0x68a0 kernel/fork.c:1363
 [<ffffffff810d186e>] _do_fork+0x14e/0xdc0 kernel/fork.c:1806
 [<ffffffff810d253f>] sys_fork+0x1f/0x30 kernel/fork.c:1877
 [<ffffffff82718cb7>] tracesys+0x88/0x8d
Code: fb ff ff 48 89 f8 48 c1 e8 03 42 0f b6 14 20 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 e2 05 00 00 f6 83 d6 fb ff ff 20 <75> 91 e8 2d ae 1e ff 4c 89 ef e8 15 40 2a ff 48 85 c0 48 89 c3 
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'getty' (3241) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1548kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (3441) (tgid 3441), adj 1000,
   to free 35348kB on behalf of 'syz-executor.2' (3229) because
   cache 648kB is below limit 6144kB for oom_score_adj 0
   Free memory is 1548kB above reserved

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/04/29 11:13 https://android.googlesource.com/kernel/common android-4.4 62872f952d6b b617407b .config console log report ci-android-44-kasan-gce
* Struck through repros no longer work on HEAD.