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INFO: task hung in netdev_run_todo

Status: closed as invalid on 2019/10/23 07:29
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+8cd13ab48843d67c58f0@syzkaller.appspotmail.com
First crash: 2913d, last: 2354d
▶ ▼ Duplicate bugs (8)
Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
INFO: task hung in check_lifetime net 1 1 2915d 2914d 0/29 closed as dup on 2018/02/12 10:05
INFO: task hung in __tun_chr_ioctl net 1 2 2642d 2874d 0/29 closed as dup on 2018/03/19 06:35
INFO: task hung in tun_chr_close net 1 5 2323d 2905d 0/29 closed as dup on 2018/02/16 08:24
INFO: task hung in fib6_rules_net_exit net 1 1 2863d 2862d 0/29 closed as dup on 2018/03/31 16:17
INFO: task hung in tunnel_key_exit_net net 1 syz 8 2486d 2862d 0/29 closed as dup on 2018/03/31 15:45
INFO: task hung in reg_check_chans_work net 1 15 2848d 2907d 0/29 closed as dup on 2018/02/14 15:33
INFO: task hung in ip6gre_exit_batch_net net 1 6 2304d 2797d 0/29 closed as dup on 2018/06/04 15:23
INFO: task hung in linkwatch_event net 1 C 82 2295d 2907d 0/29 closed as dup on 2018/02/14 15:33
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
INFO: task hung in netdev_run_todo 1 (2) 2018/06/08 08:20
▶ ▼ Similar bugs (16)
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 1180d 1496d 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 147d 147d 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 35d 35d 0/3 upstream: reported on 2025/12/26 15:48
linux-4.19 INFO: task hung in netdev_run_todo (2) 1 3 1987d 2035d 0/1 auto-closed as invalid on 2020/12/20 04:57
android-44 INFO: task hung in netdev_run_todo 1 1 2848d 2848d 0/2 auto-closed as invalid on 2019/02/22 12:49
upstream INFO: task hung in netdev_run_todo (4) wireguard ppp 1 749 7d13h 478d 0/29 upstream: reported on 2024/10/09 19:06
android-6-12 INFO: task hung in netdev_run_todo (2) 1 8 now 8d20h 0/1 premoderation: reported on 2026/01/22 03:02
linux-4.19 INFO: task hung in netdev_run_todo 1 1 2313d 2313d 0/1 auto-closed as invalid on 2020/01/29 06:48
upstream INFO: task hung in netdev_run_todo (3) net 1 24 591d 629d 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 826d 826d 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 16d 16d 0/2 upstream: reported on 2026/01/14 20:32
upstream INFO: task hung in netdev_run_todo (2) staging wireguard usb 1 C error 241 717d 1874d 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 2841d 2841d 0/3 auto-closed as invalid on 2019/02/22 14:57
linux-4.14 INFO: task hung in netdev_run_todo 1 1 1174d 1174d 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 77d 222d 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 439d 620d 0/3 auto-obsoleted due to no activity on 2025/01/26 20:30

Sample crash report:
INFO: task kworker/u4:3:86 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:3    D24280    86      2 0x80004000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4003
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 netdev_run_todo+0x4d4/0x7b0 net/core/dev.c:8992
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112
 ip_tunnel_delete_nets+0x423/0x5f0 net/ipv4/ip_tunnel.c:1114
 vti_exit_batch_net+0x23/0x30 net/ipv4/ip_vti.c:474
 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:175
 cleanup_net+0x4e2/0xa60 net/core/net_namespace.c:594
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/0:12:13275 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:12    D26304 13275      2 0x80004000
Workqueue: events linkwatch_event
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4003
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 linkwatch_event+0xf/0x70 net/core/link_watch.c:242
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/1:23:20405 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:23    D27608 20405      2 0x80004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4003
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 addrconf_dad_work+0xad/0x1150 net/ipv6/addrconf.c:4032
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/0:15:20555 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:15    D27272 20555      2 0x80004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4003
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 addrconf_dad_work+0xad/0x1150 net/ipv6/addrconf.c:4032
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task syz-executor.3:24107 blocked for more than 144 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D24544 24107      1 0x80004002
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline]
 synchronize_rcu_expedited+0x544/0x5b0 kernel/rcu/tree_exp.h:816
 synchronize_net+0x3b/0x60 net/core/dev.c:9264
 rollback_registered_many+0xa37/0xdd0 net/core/dev.c:8232
 rollback_registered+0x109/0x1d0 net/core/dev.c:8243
 unregister_netdevice_queue net/core/dev.c:9290 [inline]
 unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9283
 unregister_netdevice include/linux/netdevice.h:2631 [inline]
 __tun_detach+0xd8a/0x1040 drivers/net/tun.c:723
 tun_detach drivers/net/tun.c:740 [inline]
 tun_chr_close+0xe0/0x180 drivers/net/tun.c:3442
 __fput+0x2ff/0x890 fs/file_table.c:280
 ____fput+0x16/0x20 fs/file_table.c:313
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x92f/0x2e50 kernel/exit.c:879
 do_group_exit+0x135/0x360 kernel/exit.c:983
 __do_sys_exit_group kernel/exit.c:994 [inline]
 __se_sys_exit_group kernel/exit.c:992 [inline]
 __x64_sys_exit_group+0x44/0x50 kernel/exit.c:992
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: 24 60 48 8b 42 08 48 8b 4a 10 48 8b 5a 18 48 8b 72 20 48 8b 7a 28 48 8b 3f 4c 8b 42 30 48 8b 52 38 48 85 d2 76 62 48 89 44 24 <58> 4c 89 44 24 28 48 89 0c 24 48 89 5c 24 08 48 c7 44 24 10 00 00
RSP: 002b:00007ffc20b38888 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 0000000000459829
RDX: 0000000000413430 RSI: 0000000000a74ef0 RDI: 0000000000000000
RBP: 00000000004be569 R08: 000000000000000c R09: 0000000000000000
R10: 0000555556663940 R11: 0000000000000246 R12: 00007ffc20b39b30
R13: 000055555666c980 R14: 0000000000000000 R15: 00007ffc20b3abc0
INFO: task syz-executor.0:24146 blocked for more than 144 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D29488 24146  23989 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4003
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 sock_do_ioctl+0x24e/0x2f0 net/socket.c:1051
 sock_ioctl+0x3ed/0x780 net/socket.c:1189
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: 24 60 48 8b 42 08 48 8b 4a 10 48 8b 5a 18 48 8b 72 20 48 8b 7a 28 48 8b 3f 4c 8b 42 30 48 8b 52 38 48 85 d2 76 62 48 89 44 24 <58> 4c 89 44 24 28 48 89 0c 24 48 89 5c 24 08 48 c7 44 24 10 00 00
RSP: 002b:00007f68a8df6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f68a8df76d4
R13: 00000000004c31dd R14: 00000000004d6918 R15: 00000000ffffffff
INFO: task syz-executor.1:24152 blocked for more than 144 seconds.
      Not tainted 5.3.0-rc5+ #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28384 24152      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4003
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock net/core/rtnetlink.c:72 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:657
 __sys_sendto+0x262/0x380 net/socket.c:1952
 __do_sys_sendto net/socket.c:1964 [inline]
 __se_sys_sendto net/socket.c:1960 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1960
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x413673
Code: 3b 44 88 37 48 8d 42 04 48 8d 4f ff eb 0a c6 01 00 48 83 c0 04 48 ff c9 4c 39 d8 76 f1 31 d2 49 8d 5b 02 48 39 c3 75 0a 0f b6 <01> 83 e0 cc 09 c2 88 11 48 8b 6c 24 48 48 83 c4 50 c3 48 89 d0 48
RSP: 002b:00007ffef3697e48 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000413673
RDX: 0000000000000028 RSI: 0000000000a70070 RDI: 0000000000000003
RBP: 00007ffef3697eb0 R08: 00007ffef3697e50 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffef36981b8 R14: 0000000000000000 R15: 0000000000000000
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 PID: 1057 Comm: khungtaskd Not tainted 5.3.0-rc5+ #119
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0x9d0/0xef0 kernel/hung_task.c:289
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/08/21 04:34 upstream 15d90b242290 4ea67ff8 .config console log report ci-upstream-kasan-gce-root
2018/12/10 12:27 upstream 40e020c129cf 6565f24d .config console log report ci-upstream-kasan-gce-smack-root
2018/11/01 15:47 upstream 5b7449810ae6 1f38e9ae .config console log report ci-upstream-kasan-gce-smack-root
2018/09/24 00:00 upstream 6bf4ca7fbc85 28d9ac76 .config console log report ci-upstream-kasan-gce-smack-root
2018/03/29 15:07 upstream 0b412605ef5f d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/02/08 07:43 upstream 581e400ff935 9fb5ec43 .config console log report ci-upstream-kasan-gce-386
2019/07/02 04:12 bpf-next 8daed7677a1d cccc4302 .config console log report ci-upstream-bpf-next-kasan-gce
2019/06/15 20:57 net-next-old 877cd9ffbc9c 442206d7 .config console log report ci-upstream-net-kasan-gce
2018/03/31 14:18 net-next-old c0b6edef0bf0 8fbce0e4 .config console log report ci-upstream-net-kasan-gce
2018/03/30 17:19 net-next-old 18845557fd6f d47f0ed6 .config console log report ci-upstream-net-kasan-gce
2018/03/30 16:28 net-next-old 18845557fd6f d47f0ed6 .config console log report ci-upstream-net-kasan-gce
2019/02/22 19:23 linux-next 94a47529a645 6a5fcca4 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.