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INFO: task hung in msleep (3)

Status: auto-obsoleted due to no activity on 2026/05/28 05:58
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
First crash: 193d, last: 114d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
fe7535ae-6e59-47fc-bcb4-b03088c927cc assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in msleep (3) 2026/05/23 05:09 2026/05/23 05:09 2026/05/23 06:14 c69befb30ac10e158cc9d1557b508ee3f0eca1de

			
		
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in msleep (2) kernel 1 3 441d 568d 0/29 auto-obsoleted due to no activity on 2025/07/05 04:05
upstream INFO: task hung in msleep net 1 2 753d 757d 0/29 auto-obsoleted due to no activity on 2024/08/26 19:16
upstream INFO: task can't die in msleep net 1 C done 10 1913d 1910d 0/29 auto-obsoleted due to no activity on 2023/04/25 11:23

Sample crash report:
INFO: task kworker/0:10:23279 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:10    state:D stack:22112 pid:23279 tgid:23279 ppid:2      task_flags:0x4288060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5340 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 schedule_timeout_uninterruptible kernel/time/sleep_timeout.c:158 [inline]
 msleep+0xa1/0x100 kernel/time/sleep_timeout.c:318
 hub_port_debounce+0x204/0x330 drivers/usb/core/hub.c:4728
 hub_event+0x4991/0x4f30 drivers/usb/core/hub.c:5998
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_exp_gp_kthr/18:
1 lock held by khungtaskd/31:
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5582:
 #0: ffff8880354f30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by udevd/5823:
 #0: ffff88804d7680a0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183
 #1: ffff88803b1c8088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
 #2: ffff8880532a53c8 (kn->active#17){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff8880532a53c8 (kn->active#17){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
 #3: ffff88807b0cb198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline]
 #3: ffff88807b0cb198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
2 locks held by kworker/u8:11/20286:
 #0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655
 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
5 locks held by syz.4.3093/21771:
4 locks held by kworker/0:8/23277:
3 locks held by kworker/0:10/23279:
 #0: ffff88813fe0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
 #0: ffff88813fe0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
 #1: ffffc9000644fc40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #1: ffffc9000644fc40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
 #2: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #2: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
5 locks held by kworker/0:1/28508:
 #0: ffff8880222cd548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
 #0: ffff8880222cd548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
 #1: ffffc90004987c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #1: ffffc90004987c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
 #2: ffff888029ac6198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff888029ac6198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
 #3: ffff88807b0cb198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #3: ffff88807b0cb198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
 #4: ffff8880298c3568 (hcd->bandwidth_mutex){+.+.}-{4:4}, at: usb_set_configuration+0x53e/0x2110 drivers/usb/core/message.c:2075
1 lock held by syz-executor/29725:
1 lock held by syz.3.5295/29735:
 #0: ffffffff8fbcc908 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
 #0: ffffffff8fbcc908 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
1 lock held by syz.1.5296/29745:
 #0: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #0: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xfd9/0x1030 kernel/hung_task.c:515
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 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 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 7e 6d 02 c3 cc cc cc cc cc cc cc 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 43 1d 1c 00 fb f4 <e9> 7c ea 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000246
RAX: 000000000327dc39 RBX: ffffffff819a80dd RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8def2b4b RDI: ffffffff8c27aa00
RBP: ffffffff8e407eb0 R08: ffff8880b863395b R09: 1ffff110170c672b
R10: dffffc0000000000 R11: ffffed10170c672c R12: ffffffff901185b0
R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125464000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000404030 CR3: 000000000e54c000 CR4: 00000000003526f0
DR0: 0000000000000003 DR1: 0000000000000000 DR2: 000000000000008e
DR3: 000000000000057a DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1bd/0x500 kernel/sched/idle.c:332
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
 rest_init+0x2de/0x300 init/main.c:760
 start_kernel+0x385/0x3d0 init/main.c:1210
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/27 05:52 upstream a75cb869a8cc a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in msleep
2025/12/09 18:56 upstream cb015814f8b6 fc20f974 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm32 INFO: task hung in msleep
* Struck through repros no longer work on HEAD.