INFO: task hung in do_uevent

Status: upstream: reported C repro on 2026/08/07 00:00
Subsystems: gfs2
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+b114bbe890d76037877c@syzkaller.appspotmail.com
First crash: 7d07h, last: 11h23m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
42178c03 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in do_uevent 2026/08/02 01:38 2026/08/02 01:38 2026/08/02 02:07 e611ffe1
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [gfs2?] INFO: task hung in do_uevent 0 (1) 2026/08/07 00:00
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in do_uevent 1 2 3d02h 3d02h 0/3 upstream: reported on 2026/08/05 00:48
linux-6.6 INFO: task hung in do_uevent 1 3 3d02h 3d05h 0/2 upstream: reported on 2026/08/04 22:04
linux-6.1 INFO: task hung in do_uevent 1 5 3d02h 3d06h 0/3 upstream: reported on 2026/08/04 21:23

Sample crash report:
INFO: task syz-executor291:5623 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor291 state:D stack:26184 pid:5623  tgid:5623  ppid:5622   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x125c/0x6730 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0xdd/0x2c0 kernel/sched/core.c:7326
 do_uevent+0x427/0x530 fs/dlm/lockspace.c:206
 new_lockspace fs/dlm/lockspace.c:583 [inline]
 __dlm_new_lockspace+0x1698/0x1fa0 fs/dlm/lockspace.c:638
 dlm_new_user_lockspace+0x60/0x90 fs/dlm/lockspace.c:671
 device_create_lockspace fs/dlm/user.c:414 [inline]
 device_write+0x930/0x1c90 fs/dlm/user.c:606
 vfs_write+0x2aa/0x1050 fs/read_write.c:685
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faf45fdf6c9
RSP: 002b:00007ffc57d9a3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007faf45fdf6c9
RDX: 0000000000000080 RSI: 0000200000000d00 RDI: 0000000000000005
RBP: 6769666e6f632f2e R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffc57d9a518
R13: 0000200000000008 R14: 00007faf46072c40 R15: 0000000000000002
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:2/36:
 #0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:667
 #1: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:218 [inline]
 #1: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2e8e/0x6730 kernel/sched/core.c:7228
 #2: ffff8880b8426298 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x124/0x1d0 kernel/time/timer.c:1004
 #3: ffffffff9b978ca0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x144/0x4b0 lib/debugobjects.c:873
 #4: ffffffff8ea99840 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
1 lock held by klogd/4968:
 #0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:667
2 locks held by getty/5376:
 #0: ffff8880357b10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor291/5623:
 #0: ffffffff9b7cf4c0 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xb8/0x1fa0 fs/dlm/lockspace.c:632
1 lock held by dlm_recoverd/5625:
 #0: ffff888079814a18 (&ls->ls_in_recovery){+.+.}-{4:4}, at: dlm_recoverd+0xbd/0x1f90 fs/dlm/recoverd.c:400

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x141/0x190 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xcb1/0x1030 kernel/hung_task.c:561
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: d6 8b 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d a3 5f 10 00 fb f4 <e9> 3c 4a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e807e10 EFLAGS: 00000246
RAX: 00000000000c7b8b RBX: ffffffff8e891480 RCX: ffffffff8bbb42d5
RDX: 0000000000000000 RSI: ffffffff8e1a8186 RDI: ffffffff8c402680
RBP: fffffbfff1d12290 R08: 0000000000000001 R09: ffffed101708678d
R10: ffff8880b8433c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffffff1d00fc6 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888123dd8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558a95fb1660 CR3: 000000000e994000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:768
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
 rest_init+0x251/0x260 init/main.c:717
 start_kernel+0x48e/0x490 init/main.c:1175
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x158
 </TASK>

Crashes (38):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/05 01:24 upstream 848acc8ffe1b d4abbeac .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/05 00:47 upstream 848acc8ffe1b d4abbeac .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/05 02:41 linux-next cc2b5f627e8c d4abbeac .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in do_uevent
2026/08/07 16:22 upstream 364465ab19de e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_uevent
2026/08/07 16:19 upstream 364465ab19de e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_uevent
2026/08/07 08:28 upstream 364465ab19de c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/05 23:59 upstream 0d8395707651 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_uevent
2026/08/04 18:31 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 18:14 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 18:09 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 17:07 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 17:02 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 16:19 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 16:01 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 15:50 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 15:45 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 15:16 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 15:16 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in do_uevent
2026/08/04 15:07 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:59 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:59 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 14:56 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:54 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:54 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 14:52 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 14:48 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:44 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:36 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in do_uevent
2026/08/04 14:00 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 13:39 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 13:31 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/08/04 13:29 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in do_uevent
2026/07/31 22:56 upstream 8ba098e6b6ff 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/07/31 19:55 upstream 8ba098e6b6ff 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in do_uevent
2026/08/04 19:23 linux-next cc2b5f627e8c d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in do_uevent
2026/08/04 18:08 linux-next cc2b5f627e8c d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in do_uevent
2026/08/04 17:17 linux-next cc2b5f627e8c d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in do_uevent
2026/08/04 13:21 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in do_uevent
* Struck through repros no longer work on HEAD.