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INFO: task hung in chown_common (3)

Status: auto-closed as invalid on 2021/05/20 23:06
Subsystems: fuse
[Documentation on labels]
First crash: 1212d, last: 1161d
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in chown_common (2) 1 477d 477d 0/1 upstream: reported on 2023/01/05 10:16
upstream INFO: task hung in chown_common fs 35 2008d 2116d 0/26 closed as invalid on 2018/12/31 08:00
android-414 INFO: task hung in chown_common 1 1821d 1821d 0/1 auto-closed as invalid on 2019/10/25 08:39
upstream INFO: task hung in chown_common (5) fuse 1 517d 517d 0/26 auto-obsoleted due to no activity on 2023/04/09 00:18
android-49 INFO: task hung in chown_common 10 2070d 2117d 0/3 auto-closed as invalid on 2019/02/22 14:39
upstream INFO: task hung in chown_common (2) fs 1 1460d 1460d 0/26 auto-closed as invalid on 2020/07/25 16:03
upstream INFO: task hung in chown_common (4) v9fs C error inconclusive 7 653d 781d 0/26 closed as invalid on 2022/10/12 18:37
linux-4.19 INFO: task hung in chown_common 2 881d 919d 0/1 auto-closed as invalid on 2022/03/26 21:13
upstream INFO: task can't die in iget5_locked fuse 7 1156d 1181d 20/26 fixed on 2021/04/09 19:46

Sample crash report:
INFO: task syz-executor.1:12913 blocked for more than 143 seconds.
      Not tainted 5.11.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:29632 pid:12913 ppid:  8436 flags:0x00000004
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write_common kernel/locking/rwsem.c:1258 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x132/0x150 kernel/locking/rwsem.c:1407
 inode_lock include/linux/fs.h:773 [inline]
 chown_common+0x2d0/0x550 fs/open.c:671
 do_fchownat+0x126/0x1e0 fs/open.c:704
 __do_sys_chown fs/open.c:724 [inline]
 __se_sys_chown fs/open.c:722 [inline]
 __x64_sys_chown+0x77/0xb0 fs/open.c:722
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x466019
RSP: 002b:00007fbdfe8f1188 EFLAGS: 00000246 ORIG_RAX: 000000000000005c
RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000466019
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200004c0
RBP: 00000000004bd067 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008
R13: 00007ffcbd4311df R14: 00007fbdfe8f1300 R15: 0000000000022000
INFO: task syz-executor.1:12926 blocked for more than 143 seconds.
      Not tainted 5.11.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:27776 pid:12926 ppid:  8436 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write_common kernel/locking/rwsem.c:1258 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x132/0x150 kernel/locking/rwsem.c:1407
 inode_lock include/linux/fs.h:773 [inline]
 lock_mount+0x8a/0x2e0 fs/namespace.c:2198
 do_new_mount_fc fs/namespace.c:2824 [inline]
 do_new_mount fs/namespace.c:2883 [inline]
 path_mount+0x1787/0x20c0 fs/namespace.c:3211
 do_mount fs/namespace.c:3224 [inline]
 __do_sys_mount fs/namespace.c:3432 [inline]
 __se_sys_mount fs/namespace.c:3409 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3409
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x466019
RSP: 002b:00007fbdfe8af188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 000000000056c158 RCX: 0000000000466019
RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000
RBP: 00000000004bd067 R08: 0000000020002140 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c158
R13: 00007ffcbd4311df R14: 00007fbdfe8af300 R15: 0000000000022000
INFO: task syz-executor.1:12933 blocked for more than 143 seconds.
      Not tainted 5.11.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:29080 pid:12933 ppid:  8436 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write_common kernel/locking/rwsem.c:1258 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x132/0x150 kernel/locking/rwsem.c:1407
 inode_lock include/linux/fs.h:773 [inline]
 chown_common+0x2d0/0x550 fs/open.c:671
 do_fchownat+0x126/0x1e0 fs/open.c:704
 __do_sys_chown fs/open.c:724 [inline]
 __se_sys_chown fs/open.c:722 [inline]
 __x64_sys_chown+0x77/0xb0 fs/open.c:722
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x466019
RSP: 002b:00007fbdfe88e188 EFLAGS: 00000246 ORIG_RAX: 000000000000005c
RAX: ffffffffffffffda RBX: 000000000056c200 RCX: 0000000000466019
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200004c0
RBP: 00000000004bd067 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c200
R13: 00007ffcbd4311df R14: 00007fbdfe88e300 R15: 0000000000022000

Showing all locks held in the system:
2 locks held by kworker/u4:1/24:
 #0: ffff8880b9d34d18 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1320 [inline]
 #0: ffff8880b9d34d18 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x217/0x21a0 kernel/sched/core.c:4995
 #1: ffff8880b9d20088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833
1 lock held by khungtaskd/1649:
 #0: ffffffff8bd73da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6259
1 lock held by in:imklog/8131:
 #0: ffff888012566430 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947
2 locks held by syz-executor.1/12905:
2 locks held by syz-executor.1/12913:
 #0: ffff88807cc7a460 (sb_writers#20){.+.+}-{0:0}, at: do_fchownat+0x101/0x1e0 fs/open.c:701
 #1: ffff888078671850 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline]
 #1: ffff888078671850 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: chown_common+0x2d0/0x550 fs/open.c:671
1 lock held by syz-executor.1/12926:
 #0: ffff888078671850 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline]
 #0: ffff888078671850 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2198
2 locks held by syz-executor.1/12933:
 #0: ffff88807cc7a460 (sb_writers#20){.+.+}-{0:0}, at: do_fchownat+0x101/0x1e0 fs/open.c:701
 #1: ffff888078671850 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline]
 #1: ffff888078671850 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: chown_common+0x2d0/0x550 fs/open.c:671

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1649 Comm: khungtaskd Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd43/0xfa0 kernel/hung_task.c:294
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12905 Comm: syz-executor.1 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:202 [inline]
RIP: 0010:arch_atomic_fetch_add_unless include/linux/atomic-arch-fallback.h:1163 [inline]
RIP: 0010:arch_atomic_add_unless include/linux/atomic-arch-fallback.h:1183 [inline]
RIP: 0010:atomic_add_unless include/asm-generic/atomic-instrumented.h:789 [inline]
RIP: 0010:_atomic_dec_and_lock+0x7a/0x100 lib/dec_and_lock.c:24
Code: 44 89 e6 bf 01 00 00 00 e8 73 07 9a fd 41 83 fc 01 74 39 e8 48 01 9a fd 41 8d 54 24 ff 44 89 e0 f0 0f b1 13 41 0f 94 c5 31 ff <41> 89 c4 44 89 ee e8 0b 09 9a fd 45 84 ed 74 c1 45 31 e4 e8 1e 01
RSP: 0018:ffffc90001de74b8 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff888078671908 RCX: ffffc9000a792000
RDX: 0000000000000001 RSI: ffffffff83d8d6d8 RDI: 0000000000000000
RBP: ffff888078671788 R08: 0000000000000001 R09: ffff88807867190b
R10: ffffffff83d8d6cd R11: 0000000000000000 R12: 0000000000000002
R13: ffff88807cc7a001 R14: ffff888078671788 R15: ffffc90001de75a0
FS:  00007fbdfe912700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fab59966000 CR3: 0000000013564000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 iput.part.0+0x67/0x810 fs/inode.c:1671
 iput+0x58/0x70 fs/inode.c:1669
 fuse_iget+0x24e/0x610 fs/fuse/inode.c:356
 fuse_lookup_name+0x447/0x630 fs/fuse/dir.c:439
 fuse_lookup.part.0+0xdf/0x390 fs/fuse/dir.c:469
 fuse_lookup+0x70/0x90 fs/fuse/dir.c:465
 __lookup_slow+0x24c/0x480 fs/namei.c:1544
 lookup_slow fs/namei.c:1561 [inline]
 walk_component+0x418/0x6a0 fs/namei.c:1861
 lookup_last fs/namei.c:2312 [inline]
 path_lookupat+0x1ba/0x830 fs/namei.c:2336
 filename_lookup+0x19f/0x560 fs/namei.c:2369
 user_path_at include/linux/namei.h:59 [inline]
 vfs_statx+0x142/0x390 fs/stat.c:185
 vfs_fstatat fs/stat.c:207 [inline]
 vfs_stat include/linux/fs.h:3118 [inline]
 __do_sys_newstat+0x91/0x110 fs/stat.c:349
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x466019
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbdfe912188 EFLAGS: 00000246 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466019
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020009040
RBP: 00000000004bd067 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffcbd4311df R14: 00007fbdfe912300 R15: 0000000000022000

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/19 23:04 upstream f40ddce88593 f689d40a .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in chown_common
2021/02/19 18:11 upstream f40ddce88593 f689d40a .config console log report info ci-upstream-kasan-gce INFO: task hung in chown_common
2021/02/03 06:29 upstream 3aaf0a27ffc2 624dad51 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in chown_common
2021/02/03 04:17 upstream 3aaf0a27ffc2 624dad51 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in chown_common
2021/01/28 04:37 upstream 76c057c84d28 eefc07f2 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in chown_common
2021/02/19 20:02 upstream f40ddce88593 f689d40a .config console log report info ci-upstream-kasan-gce-386 INFO: task hung in chown_common
2021/02/03 02:50 upstream 3aaf0a27ffc2 624dad51 .config console log report info ci-upstream-kasan-gce-386 INFO: task hung in chown_common
2021/01/13 16:12 upstream e609571b5ffa a945f0a3 .config console log report info ci-upstream-kasan-gce-root
2020/12/31 05:41 upstream f6e1ea196492 5cc121d6 .config console log report info ci-upstream-kasan-gce-selinux-root
2020/12/31 05:37 upstream f6e1ea196492 5cc121d6 .config console log report info ci-upstream-kasan-gce
2020/12/31 05:35 upstream f6e1ea196492 5cc121d6 .config console log report info ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.