INFO: task hung in netdev_run_todo (2)

Status: premoderation: reported on 2026/01/22 03:02
Reported-by: syzbot+f4c9b9509664219a17ad@syzkaller.appspotmail.com
First crash: 226d, last: 1d06h
▶ ▼ Similar bugs (18)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in netdev_run_todo (3) 1 15 1398d 1714d 0/1 auto-obsoleted due to no activity on 2023/03/07 08:19
linux-6.6 INFO: task hung in netdev_run_todo 1 1 364d 364d 0/2 auto-obsoleted due to no activity on 2025/12/14 15:00
linux-5.15 INFO: task hung in netdev_run_todo (3) 1 1 252d 252d 0/3 auto-obsoleted due to no activity on 2026/04/05 15:48
upstream INFO: task hung in netdev_run_todo net 1 12 2572d 3127d 0/29 closed as invalid on 2019/10/23 07:29
linux-4.19 INFO: task hung in netdev_run_todo (2) 1 3 2205d 2252d 0/1 auto-closed as invalid on 2020/12/20 04:57
linux-5.15 INFO: task hung in netdev_run_todo (4) 1 syz 2 16d 21d 0/3 upstream: reported syz repro on 2026/08/15 05:07
android-44 INFO: task hung in netdev_run_todo 1 1 3066d 3066d 0/2 auto-closed as invalid on 2019/02/22 12:49
upstream INFO: task hung in netdev_run_todo (4) prio:high wireguard 1 959 14h04m 695d 0/29 upstream: reported on 2024/10/09 19:06
linux-4.19 INFO: task hung in netdev_run_todo 1 1 2531d 2531d 0/1 auto-closed as invalid on 2020/01/29 06:48
upstream INFO: task hung in netdev_run_todo (3) net 1 24 809d 846d 0/29 auto-obsoleted due to no activity on 2024/08/07 04:24
linux-5.15 INFO: task hung in netdev_run_todo 1 1 1044d 1044d 0/3 auto-obsoleted due to no activity on 2024/02/04 09:09
linux-6.6 INFO: task hung in netdev_run_todo (2) 1 1 233d 233d 0/2 auto-obsoleted due to no activity on 2026/04/24 20:32
upstream INFO: task hung in netdev_run_todo (2) staging wireguard usb 1 syz, C error 241 935d 2091d 0/29 auto-obsoleted due to no activity on 2024/05/05 22:51
android-49 INFO: task hung in netdev_run_todo 1 1 3058d 3058d 0/3 auto-closed as invalid on 2019/02/22 14:57
linux-4.14 INFO: task hung in netdev_run_todo 1 1 1391d 1391d 0/1 auto-obsoleted due to no activity on 2023/03/13 17:45
android-6-12 INFO: task hung in netdev_run_todo 1 184 295d 440d 0/1 auto-obsoleted due to no activity on 2026/01/03 01:56
linux-5.15 INFO: task hung in netdev_run_todo (2) 1 54 656d 837d 0/3 auto-obsoleted due to no activity on 2025/01/26 20:30
upstream INFO: task can't die in netdev_run_todo net 1 syz error 2 1814d 2207d 0/29 auto-obsoleted due to no activity on 2023/04/16 04:59

Sample crash report:
INFO: task syz-executor:2122 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:2122  tgid:2122  ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6063 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7883
 __schedule_loop kernel/sched/core.c:7960 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7975
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rcu_barrier+0x4d/0x580 kernel/rcu/tree.c:4589
 netdev_run_todo+0x118/0xce0 net/core/dev.c:10912
 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
 tun_detach drivers/net/tun.c:704 [inline]
 tun_chr_close+0xc5/0x150 drivers/net/tun.c:3520
 __fput+0x208/0xa30 fs/file_table.c:447
 ____fput+0x20/0x30 fs/file_table.c:475
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa46/0x2850 kernel/exit.c:955
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
 get_signal+0x134c/0x1490 kernel/signal.c:2933
 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc137f592d7
RSP: 002b:00007ffdd44e0b50 EFLAGS: 00000202
RAX: fffffffffffffffc RBX: 00005555809e2500 RCX: 00007fc137f592d7
RDX: 00007ffdd44e0b90 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffdd44e0bfc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000001388
R13: 00000000000927c0 R14: 0000000000037a72 R15: 00007ffdd44e0c50
 </TASK>
INFO: task syz.0.721:2925 blocked for more than 127 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.721       state:D stack:0     pid:2925  tgid:2925  ppid:295    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6063 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7883
 __schedule_loop kernel/sched/core.c:7960 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7975
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rcu_barrier+0x4d/0x580 kernel/rcu/tree.c:4589
 netdev_run_todo+0x118/0xce0 net/core/dev.c:10912
 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
 tun_detach drivers/net/tun.c:704 [inline]
 tun_chr_close+0xc5/0x150 drivers/net/tun.c:3520
 __fput+0x208/0xa30 fs/file_table.c:447
 ____fput+0x20/0x30 fs/file_table.c:475
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa46/0x2850 kernel/exit.c:955
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
 get_signal+0x134c/0x1490 kernel/signal.c:2933
 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f601195e98e
RSP: 002b:00007f6012906f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f60129076c0 RCX: 00007f601195e98e
RDX: 00007f6012906fb0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6011a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6011c26038 R14: 00007f6011c25fa0 R15: 00007ffc6de9b018
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0aeaa9ab517470fdb6a7d2a0748c92464a674951
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xe45/0xf90 kernel/hung_task.c:423
 kthread+0x2c4/0x360 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 45 Comm: kworker/1:1 Not tainted syzkaller #0 0aeaa9ab517470fdb6a7d2a0748c92464a674951
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
RIP: 0010:stack_trace_consume_entry+0xa6/0x2a0 kernel/stacktrace.c:93
Code: 41 0f b6 04 17 84 c0 0f 85 8d 01 00 00 45 89 34 24 b0 01 e9 a2 00 00 00 31 c0 e9 9b 00 00 00 48 89 f8 48 c1 e8 03 80 3c 10 00 <48> 89 75 c0 74 2b 49 89 ff 49 89 d4 4c 89 45 c8 4d 89 ce 4c 89 55
RSP: 0018:ffffc900002301d0 EFLAGS: 00000246
RAX: 1ffff9200004605c RBX: 1ffff9200004605e RCX: 0000000000046000
RDX: dffffc0000000000 RSI: ffffffff81508c28 RDI: ffffc900002302e0
RBP: ffffc90000230218 R08: ffffc900002302f0 R09: ffffc900002302e8
R10: 000000000000000e R11: ffffffff8175a5e0 R12: ffffc900002302ec
R13: 1ffff9200004605d R14: 0000000000000000 R15: 1ffff9200004605d
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f64489f84c0 CR3: 0000000120996000 CR4: 00000000003526b0
DR0: 000000006000000c DR1: 0000000000000000 DR2: 0000000000000000

Crashes (133):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/04 04:16 android16-6.12 1eab233d5fae 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/09/03 11:46 android16-6.12 8473ff8a565c 6a988719 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/09/01 12:32 android16-6.12 77b3c87e00dc 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/29 18:09 android16-6.12 36bee94a7cf9 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/29 10:01 android16-6.12 36bee94a7cf9 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/28 14:30 android16-6.12 3ebc81d80f95 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/28 02:05 android16-6.12 3ebc81d80f95 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/24 17:17 android16-6.12 e8c85685a629 b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/17 15:54 android16-6.12 b21af26d1628 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/14 09:35 android16-6.12 c3360dde0a9e b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/08/06 22:33 android16-6.12 749a6f9d41aa c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/31 07:30 android16-6.12 7d66c8550304 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/29 22:12 android16-6.12 f1c9c21d1c2f 6ef5c1e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/27 23:39 android16-6.12 a12ab5a23a35 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/27 06:55 android16-6.12 579215f16d4e 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/23 04:37 android16-6.12 6599be6df4d0 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/22 20:12 android16-6.12 b739cd4ffbe5 4a865b71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/21 05:43 android16-6.12 5aeb3ef16d03 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/20 18:01 android16-6.12 c3f9cafa739b de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/19 18:02 android16-6.12 0fd55a309793 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/18 09:09 android16-6.12 0fd55a309793 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/14 13:45 android16-6.12 5dd528d5e93a 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/14 03:40 android16-6.12 5dd528d5e93a 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/11 10:45 android16-6.12 0026e4ecedf0 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/10 01:01 android16-6.12 0e0925f37543 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/07 20:16 android16-6.12 68c198f6d8bc 76cdc0c0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/05 18:40 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/07/03 19:12 android16-6.12 d36feda1de57 58bf2096 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/28 13:18 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/28 08:28 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/27 07:21 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/27 00:14 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/26 10:50 android16-6.12 cc87569b5721 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/25 23:13 android16-6.12 cc87569b5721 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/25 06:21 android16-6.12 f222c1f727d9 cfa969bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/25 00:52 android16-6.12 f222c1f727d9 302586aa .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/23 19:09 android16-6.12 8f68185b8289 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/23 12:28 android16-6.12 8f68185b8289 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/22 03:43 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/21 06:50 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/18 12:15 android16-6.12 8f68185b8289 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/17 14:45 android16-6.12 8f68185b8289 62cc6db3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/16 04:02 android16-6.12 8f68185b8289 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/14 22:09 android16-6.12 8f68185b8289 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
2026/06/13 17:29 android16-6.12 8f68185b8289 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in netdev_run_todo
* Struck through repros no longer work on HEAD.