syzbot


INFO: task hung in do_unlinkat (5)

Status: upstream: reported C repro on 2024/06/02 14:09
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+08b113332e19a9378dd5@syzkaller.appspotmail.com
First crash: 558d, last: 18h45m
Cause bisection: failed (error log, bisect log)
  
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] Monthly kernfs report (Jan 2025) 0 (1) 2025/01/16 10:12
[syzbot] [kernfs?] [bcachefs?] [exfat?] INFO: task hung in do_unlinkat (5) 0 (2) 2024/11/26 01:26
Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in do_unlinkat (2) 1 1 1051d 1051d 0/1 auto-obsoleted due to no activity on 2023/03/27 07:50
android-49 INFO: task hung in do_unlinkat 1 5 2603d 2715d 0/3 auto-closed as invalid on 2019/02/24 11:49
upstream INFO: task hung in do_unlinkat (2) fs 1 4 1709d 1709d 0/29 auto-closed as invalid on 2021/05/17 08:41
linux-6.1 INFO: task hung in do_unlinkat origin:upstream missing-backport 1 C inconclusive 12 161d 287d 0/3 upstream: reported C repro on 2024/12/30 08:52
upstream INFO: task hung in do_unlinkat exfat 1 34 2464d 2700d 0/29 closed as dup on 2018/10/27 13:26
upstream INFO: task hung in do_unlinkat (3) fs 1 2 1428d 1471d 0/29 closed as invalid on 2022/02/07 19:19
linux-4.19 INFO: task hung in do_unlinkat 1 1 1181d 1181d 0/1 auto-obsoleted due to no activity on 2022/11/17 10:56
upstream INFO: task hung in do_unlinkat (4) exfat 1 4 1020d 1126d 0/29 auto-obsoleted due to no activity on 2023/04/08 02:53
linux-5.15 INFO: task hung in do_unlinkat 1 3 371d 519d 0/3 auto-obsoleted due to no activity on 2025/01/15 03:04
Last patch testing requests (6)
Created Duration User Patch Repo Result
2025/06/15 06:54 23m retest repro upstream OK log
2025/06/15 06:54 23m retest repro upstream OK log
2025/04/05 13:56 17m retest repro upstream report log
2025/04/05 13:56 16m retest repro upstream report log
2024/12/21 18:21 17m retest repro upstream report log
2024/12/21 18:21 19m retest repro upstream report log

Sample crash report:
INFO: task syz.4.46:6197 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46        state:D stack:28232 pid:6197  tgid:6185  ppid:5801   task_flags:0x400040 flags:0x000[  285.943490][   T38] task:syz.4.46        state:D stack:28232 pid:6197  tgid:6185  ppid:5801   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1025 [inline]
 do_unlinkat+0x1c7/0x570 fs/namei.c:4724
 __do_sys_unlinkat fs/namei.c:4778 [inline]
 __se_sys_unlinkat fs/namei.c:4771 [inline]
 __x64_sys_unlinkat+0xd3/0xf0 fs/namei.c:4771
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9108eec9
RSP: 002b:00007feb8f2d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007feb912e6090 RCX: 00007feb9108eec9
RDX: 0000000000000000 RSI: 0000200000000380 RDI: ffffffffffffff9c
RBP: 00007feb91111f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb912e6128 R14: 00007feb912e6090 R15: 00007ffdffee5028
 </TASK>
INFO: task syz.4.46:6198 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46        state:D stack:26456 pid:6198  tgid:6185  ppid:5801   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1025 [inline]
 filename_create+0x1f8/0x3c0 fs/namei.c:4226
 do_mknodat+0x184/0x4d0 fs/namei.c:4359
 __do_sys_mknod fs/namei.c:4405 [inline]
 __se_sys_mknod fs/namei.c:4403 [inline]
 __x64_sys_mknod+0x8c/0xa0 fs/namei.c:4403
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9108eec9
RSP: 002b:00007feb8f2b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007feb912e6180 RCX: 00007feb9108eec9
RDX: 0000000000000708 RSI: 0000000000008000 RDI: 00002000000000c0
RBP: 00007feb91111f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb912e6218 R14: 00007feb912e6180 R15: 00007ffdffee5028
 </TASK>
INFO: task syz.4.46:6208 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46        state:D stack:27240 pid:6208  tgid:6185  ppid:5801   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1025 [inline]
 filename_create+0x1f8/0x3c0 fs/namei.c:4226
 do_mkdirat+0xa0/0x590 fs/namei.c:4478
 __do_sys_mkdirat fs/namei.c:4503 [inline]
 __se_sys_mkdirat fs/namei.c:4501 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9108d617
RSP: 002b:00007feb8ee90e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007feb8ee90ef0 RCX: 00007feb9108d617
RDX: 00000000000001ff RSI: 0000200000000040 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000040
R13: 00007feb8ee90eb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task syz.4.46:6209 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46        state:D stack:29224 pid:6209  tgid:6185  ppid:5801   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1025 [inline]
 filename_create+0x1f8/0x3c0 fs/namei.c:4226
 do_mkdirat+0xa0/0x590 fs/namei.c:4478
 __do_sys_mkdirat fs/namei.c:4503 [inline]
 __se_sys_mkdirat fs/namei.c:4501 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9108eec9
RSP: 002b:00007feb8ea6e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007feb912e6360 RCX: 00007feb9108eec9
RDX: 00000000000001c0 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007feb91111f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb912e63f8 R14: 00007feb912e6360 R15: 00007ffdffee5028
 </TASK>
INFO: task syz.4.46:6210 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46        state:D stack:29192 pid:6210  tgid:6185  ppid:5801   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 __rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114
 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
 __down_read kernel/locking/rwsem.c:1466 [inline]
 down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539
 inode_lock_shared include/linux/fs.h:995 [inline]
 lookup_slow+0x46/0x70 fs/namei.c:1832
 walk_component+0x2d2/0x400 fs/namei.c:2151
 lookup_last fs/namei.c:2652 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2676
 filename_lookup+0x212/0x570 fs/namei.c:2705
 user_path_at+0x3a/0x60 fs/namei.c:3215
 do_mount fs/namespace.c:4047 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x2d4/0x410 fs/namespace.c:4215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9108eec9
RSP: 002b:00007feb8e64b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007feb912e6450 RCX: 00007feb9108eec9
RDX: 0000200000000080 RSI: 0000200000000180 RDI: 0000000000000000
RBP: 00007feb91111f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001214040 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb912e64e8 R14: 00007feb912e6450 R15: 00007ffdffee5028
 </TASK>
INFO: task syz.4.46:6213 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46        state:D stack:28264 pid:6213  tgid:6185  ppid:5801   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 __rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114
 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
 __down_read kernel/locking/rwsem.c:1466 [inline]
 down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539
 inode_lock_shared include/linux/fs.h:995 [inline]
 lookup_slow+0x46/0x70 fs/namei.c:1832
 walk_component+0x2d2/0x400 fs/namei.c:2151
 lookup_last fs/namei.c:2652 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2676
 filename_lookup+0x212/0x570 fs/namei.c:2705
 kern_path+0x35/0x50 fs/namei.c:2863
 ovl_mount_dir_noesc fs/overlayfs/params.c:239 [inline]
 ovl_mount_dir fs/overlayfs/params.c:270 [inline]
 ovl_kern_path fs/overlayfs/params.c:396 [inline]
 ovl_parse_layer fs/overlayfs/params.c:445 [inline]
 ovl_parse_param+0xb0e/0xee0 fs/overlayfs/params.c:633
 vfs_parse_fs_param+0x1a9/0x420 fs/fs_context.c:146
 vfs_parse_fs_qstr fs/fs_context.c:187 [inline]
 vfs_parse_fs_string include/linux/fs_context.h:142 [inline]
 vfs_parse_monolithic_sep+0x25d/0x320 fs/fs_context.c:227
 do_new_mount+0x2cb/0xa10 fs/namespace.c:3723
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9108eec9
RSP: 002b:00007feb8e228038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007feb912e6540 RCX: 00007feb9108eec9
RDX: 0000200000000b80 RSI: 0000200000000180 RDI: 0000000000000000
RBP: 00007feb91111f91 R08: 0000200000000380 R09: 0000000000000000
R10: 0000000000a00008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb912e65d8 R14: 00007feb912e6540 R15: 00007ffdffee5028
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
 #0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90000127ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90000127ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
 #0: ffffffff8d7aa4c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d7aa4c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d7aa4c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/58:
 #0: ffff88801a294938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88801a294938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc9000124fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc9000124fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8ea6a9e0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669
 #3: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12807
4 locks held by kworker/u8:5/144:
 #0: ffff88814047a938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88814047a938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90003a77ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90003a77ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffff8881437600d0 (&type->s_umount_key#77){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
 #3: ffff88805c5428e8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
2 locks held by kworker/u8:9/1155:
 #0: ffff88813fe29138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88813fe29138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc9000487fba0 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc9000487fba0 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
2 locks held by dhcpcd/5464:
 #0: ffff88803a5c6918 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269
 #1: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6822
2 locks held by getty/5561:
 #0: ffff88823bf3e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5799:
3 locks held by kworker/u8:14/6021:
 #0: ffff88814cf1e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88814cf1e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc9000c557ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc9000c557ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
4 locks held by syz.4.46/6188:
2 locks held by syz.4.46/6197:
 #0: ffff888143760480 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: do_unlinkat+0x1c7/0x570 fs/namei.c:4724
2 locks held by syz.4.46/6198:
 #0: ffff888143760480 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226
2 locks held by syz.4.46/6208:
 #0: ffff888143760480 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226
2 locks held by syz.4.46/6209:
 #0: ffff888143760480 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
 #1: ffff88805c542cb8 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226
1 lock held by syz.4.46/6210:
 #0: ffff88805c542cb8 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:995 [inline]
 #0: ffff88805c542cb8 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1832
1 lock held by syz.4.46/6213:
 #0: ffff88805c542cb8 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:995 [inline]
 #0: ffff88805c542cb8 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1832
1 lock held by syz-executor/7227:
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/7285:
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
1 lock held by syz-executor/7349:
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/7746:
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/7811:
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8ea778f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
6 locks held by syz.5.279/7857:
1 lock held by syz-executor/7858:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:407
Code: 09 b3 fc 44 89 f9 d3 e5 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 6c bb 14 fd 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 87 0b be 05 cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc900001678d0 EFLAGS: 00000202
RAX: 0000000000000034 RBX: 0000000000000034 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000000003f8 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff850be350 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffffff990bef00 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888126cc9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb2e7a1dc80 CR3: 00000000402ba000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_port_out include/linux/serial_core.h:811 [inline]
 serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3192 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
 serial8250_console_write+0x1291/0x1b40 drivers/tty/serial/8250/8250_port.c:3342
 console_emit_next_record kernel/printk/printk.c:3091 [inline]
 console_flush_all+0x666/0xb40 kernel/printk/printk.c:3199
 __console_flush_and_unlock+0x9b/0x160 kernel/printk/printk.c:3258
 legacy_kthread_func+0x13b/0x1a0 kernel/printk/printk.c:3611
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (118):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/13 06:13 upstream 3a8660878839 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/10/09 09:35 upstream cd5a0afbdf80 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/10/03 18:17 upstream e406d57be7bd 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/09/29 15:55 upstream e5f0a698b34e 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/09/03 01:07 upstream e6b9dce0aeeb 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/09/02 15:43 upstream b320789d6883 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/08/18 22:51 upstream c17b750b3ad9 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/08/12 04:22 upstream 8f5ae30d69d7 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/08/05 03:42 upstream d632ab86aff2 f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/07/24 13:44 upstream 25fae0b93d1d 65d60d73 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/07/10 02:02 upstream 8c2e52ebbe88 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/07/09 11:54 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/06/28 21:58 upstream aaf724ed6926 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/06/19 06:54 upstream fb4d33ab452e ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/25 08:26 upstream d0c22de9995b ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/16 22:59 upstream 3c21441eeffc f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/09 18:03 upstream 9c69f8884904 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/08 22:39 upstream 2c89c1b655c0 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/08 01:54 upstream 707df3375124 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/04 15:36 upstream e8ab83e34bdc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/04 14:08 upstream e8ab83e34bdc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/03 10:34 upstream 95d3481af6dc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/03 06:17 upstream 2bfcee565c3a b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/05/01 19:13 upstream 4f79eaa2ceac 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/28 04:42 upstream b4432656b36e c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/27 19:45 upstream 5bc1018675ec c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/27 11:50 upstream 5bc1018675ec c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/22 10:21 upstream a33b5a08cbbd 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/21 22:43 upstream 9d7a0577c9db 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/21 04:56 upstream 6fea5fabd332 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/19 14:43 upstream 3088d26962e8 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/19 07:19 upstream 3088d26962e8 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/03/21 11:59 upstream b3ee1e460951 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/03/14 13:17 upstream 4003c9e78778 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/03/09 11:37 upstream b7c90e3e717a 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/03/06 00:38 upstream bb2281fb05e5 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/03/04 18:21 upstream 99fa936e8e4f c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/02/28 08:37 upstream 1e15510b71c9 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/02/21 00:55 upstream e9a8cac0bf89 0808a665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/02/19 05:10 upstream 6537cfb395f3 9a14138f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/02/12 04:01 upstream 09fbf3d50205 f2baddf5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/02/01 12:20 upstream 69b8923f5003 aa47157c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/01/07 21:05 upstream fbfd64d25c7a f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/01/04 21:45 upstream ab75170520d4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/12/05 18:13 upstream feffde684ac2 29f61fce .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/12/04 21:34 upstream feffde684ac2 b50eb251 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/12/01 09:08 upstream bcc8eda6d349 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/11/30 11:50 upstream 509f806f7f70 68914665 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/11/29 13:54 upstream 7af08b57bcb9 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/11/26 01:25 upstream 9f16d5e6f220 11dbc254 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/11/14 06:15 upstream 0a9b9d17f3a7 bb3f8425 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/07/31 11:51 upstream 22f546873149 6fde257d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_unlinkat
2024/06/23 12:19 upstream 5f583a3162ff edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_unlinkat
2024/05/22 04:48 upstream b6394d6f7159 1014eca7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/05/16 14:46 upstream 3c999d1ae3c7 ef5d53ed .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_unlinkat
2024/05/10 10:19 upstream 448b3fe5a0ea de979bc2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/05/03 08:20 upstream 49a73b1652c5 ddfc15a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2024/04/28 23:56 upstream e67572cd2204 07b455f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_unlinkat
2025/04/09 11:48 linux-next 46086739de22 988b336c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in do_unlinkat
* Struck through repros no longer work on HEAD.