INFO: task hung in netdev_run_todo (4)

Status: upstream: reported syz repro on 2026/08/15 05:07
Reported-by: syzbot+2271061f8b8e1bc1195e@syzkaller.appspotmail.com
First crash: 12d, last: 7d13h
▶ ▼ 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 1389d 1705d 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 356d 356d 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 244d 244d 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 2563d 3118d 0/29 closed as invalid on 2019/10/23 07:29
linux-4.19 INFO: task hung in netdev_run_todo (2) 1 3 2196d 2244d 0/1 auto-closed as invalid on 2020/12/20 04:57
android-44 INFO: task hung in netdev_run_todo 1 1 3057d 3057d 0/2 auto-closed as invalid on 2019/02/22 12:49
upstream INFO: task hung in netdev_run_todo (4) prio:high wireguard 1 956 5h20m 687d 0/29 upstream: reported on 2024/10/09 19:06
android-6-12 INFO: task hung in netdev_run_todo (2) 1 126 3d03h 217d 0/1 premoderation: reported on 2026/01/22 03:02
linux-4.19 INFO: task hung in netdev_run_todo 1 1 2522d 2522d 0/1 auto-closed as invalid on 2020/01/29 06:48
upstream INFO: task hung in netdev_run_todo (3) net 1 24 800d 838d 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 1035d 1035d 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 225d 225d 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 926d 2083d 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 3050d 3050d 0/3 auto-closed as invalid on 2019/02/22 14:57
linux-4.14 INFO: task hung in netdev_run_todo 1 1 1383d 1383d 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 286d 431d 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 648d 829d 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 1805d 2198d 0/29 auto-obsoleted due to no activity on 2023/04/16 04:59

Sample crash report:
INFO: task kworker/u4:0:9 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:23920 pid:    9 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 netdev_run_todo+0x8dd/0xac0 net/core/dev.c:10722
 nsim_destroy+0xb2/0x150 drivers/net/netdevsim/netdev.c:387
 __nsim_dev_port_del+0x155/0x1c0 drivers/net/netdevsim/dev.c:1349
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1362 [inline]
 nsim_dev_reload_destroy+0x160/0x230 drivers/net/netdevsim/dev.c:1561
 nsim_dev_reload_down+0xf9/0x160 drivers/net/netdevsim/dev.c:883
 devlink_reload+0x253/0x770 net/core/devlink.c:3963
 devlink_pernet_pre_exit+0x1aa/0x310 net/core/devlink.c:11543
 ops_pre_exit_list net/core/net_namespace.c:162 [inline]
 cleanup_net+0x58e/0xba0 net/core/net_namespace.c:615
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
INFO: task kworker/u4:3:1172 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:3    state:D stack:20992 pid: 1172 ppid:     2 flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 linkwatch_event+0xa/0x50 net/core/link_watch.c:251
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
INFO: task udevd:3559 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:25008 pid: 3559 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 device_lock include/linux/device.h:809 [inline]
 uevent_show+0x16c/0x320 drivers/base/core.c:2408
 dev_attr_show+0x50/0xb0 drivers/base/core.c:2110
 sysfs_kf_seq_show+0x316/0x4c0 fs/sysfs/file.c:61
 seq_read_iter+0x460/0xc50 fs/seq_file.c:230
 call_read_iter include/linux/fs.h:2167 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0x75e/0xd50 fs/read_write.c:485
 ksys_read+0x153/0x260 fs/read_write.c:623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9a9ec2b407
RSP: 002b:00007fff1359f990 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f9a9eb3d880 RCX: 00007f9a9ec2b407
RDX: 0000000000001000 RSI: 0000564f7dbcc040 RDI: 000000000000000c
RBP: 00007f9a9ed73ff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f9a9ed73ea0 R14: 0000000000000000 R15: 0000564f7dbbd040
 </TASK>
INFO: task dhcpcd:3851 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:25488 pid: 3851 ppid:     1 flags:0x00004202
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 vlan_ioctl_handler+0xef/0x5d0 net/8021q/vlan.c:581
 sock_ioctl+0x23b/0x700 net/socket.c:1231
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8d93e38378
RSP: 002b:00007ffd0ab4bf78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000055ac573f0900 RCX: 00007f8d93e38378
RDX: 00007ffd0ab4bf80 RSI: 0000000000008982 RDI: 000000000000000f
RBP: 00007ffd0ab4bf80 R08: 1999999999999999 R09: 0000000000000000
R10: 00007f8d93eb2fe0 R11: 0000000000000246 R12: 0000000000000002
R13: 000055ac57464d08 R14: 00007ffd0ab4c9d0 R15: 000055ac573f0900
 </TASK>
INFO: task kworker/0:10:4300 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:10    state:D stack:24464 pid: 4300 ppid:     2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4120
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
INFO: task kworker/0:19:4309 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:19    state:D stack:25184 pid: 4309 ppid:     2 flags:0x00004000
Workqueue: events nsim_dev_trap_report_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
INFO: task kworker/1:6:4384 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:6     state:D stack:25296 pid: 4384 ppid:     2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4120
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
INFO: task syz-executor:5655 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22032 pid: 5655 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 ieee80211_rate_control_ops_get net/mac80211/rate.c:192 [inline]
 rate_control_alloc net/mac80211/rate.c:239 [inline]
 ieee80211_init_rate_ctrl_alg+0x171/0x5e0 net/mac80211/rate.c:983
 ieee80211_register_hw+0x23c6/0x3a60 net/mac80211/main.c:1252
 mac80211_hwsim_new_radio+0x209d/0x4050 drivers/net/wireless/mac80211_hwsim.c:3373
 hwsim_new_radio_nl+0xa7d/0xc50 drivers/net/wireless/mac80211_hwsim.c:3949
 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0xd0b/0xfa0 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2519
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x78f/0x940 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 __sys_sendto+0x46d/0x620 net/socket.c:2073
 __do_sys_sendto net/socket.c:2085 [inline]
 __se_sys_sendto net/socket.c:2081 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2081
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f760e8fc90e
RSP: 002b:00007fff485deee8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055558c729500 RCX: 00007f760e8fc90e
RDX: 0000000000000024 RSI: 00007f760f6f2670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff485def64 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f760f6f2670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:5758 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22736 pid: 5758 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 devlink_nl_port_fill+0x346/0x8c0 net/core/devlink.c:995
 devlink_port_notify+0x4c/0x170 net/core/devlink.c:1052
 __devlink_port_type_set net/core/devlink.c:9163 [inline]
 devlink_port_type_eth_set+0x30d/0x470 net/core/devlink.c:9219
 __nsim_dev_port_add+0x82e/0xa80 drivers/net/netdevsim/dev.c:1325
 nsim_dev_port_add_all+0x37/0x100 drivers/net/netdevsim/dev.c:1372
 nsim_dev_probe+0x75e/0x9d0 drivers/net/netdevsim/dev.c:1513
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x276/0xc70 drivers/base/dd.c:595
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a7/0x480 drivers/base/dd.c:999
 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
 device_add+0xbcf/0x1050 drivers/base/core.c:3427
 nsim_bus_dev_new drivers/net/netdevsim/bus.c:435 [inline]
 new_device_store+0x3e3/0x770 drivers/net/netdevsim/bus.c:302
 kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x748/0xd70 fs/read_write.c:594
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1ef8e5e90e
RSP: 002b:00007ffed92ce488 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00005555851ff500 RCX: 00007f1ef8e5e90e
RDX: 0000000000000003 RSI: 00007ffed92ce510 RDI: 0000000000000005
RBP: 00007f1ef8f358cb R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffed92ce510 R14: 00007f1ef9c54620 R15: 0000000000000003
 </TASK>
INFO: task syz-executor:5761 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22736 pid: 5761 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 del_device_store+0xd3/0x3a0 drivers/net/netdevsim/bus.c:344
 kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x748/0xd70 fs/read_write.c:594
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6615ef390e
RSP: 002b:00007ffebc58ea38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000555582b31500 RCX: 00007f6615ef390e
RDX: 0000000000000001 RSI: 00007ffebc58eac0 RDI: 0000000000000005
RBP: 00007f6615fca8a7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffebc58eac0 R14: 00007f6616ce9620 R15: 0000000000000003
 </TASK>

Showing all locks held in the system:
7 locks held by kworker/u4:0/9:
 #0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90000ce7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8d441a50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
 #3: ffffffff8d472f68 (devlink_mutex){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0xa4/0x310 net/core/devlink.c:11534
 #4: ffff88807cb6b660 (&nsim_bus_dev->nsim_bus_reload_lock){+.+.}-{3:3}, at: nsim_dev_reload_down+0x57/0x160 drivers/net/netdevsim/dev.c:870
 #5: ffff88805a8b6400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline]
 #5: ffff88805a8b6400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x109/0x230 drivers/net/netdevsim/dev.c:1561
 #6: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x8dd/0xac0 net/core/dev.c:10722
1 lock held by khungtaskd/27:
 #0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:3/1172:
 #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90005467d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
3 locks held by kworker/0:3/1335:
 #0: ffff888016c71938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90005b67d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x82/0xa90 net/wireless/reg.c:2437
4 locks held by udevd/3559:
 #0: ffff88801e92bd58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0x9d/0xc50 fs/seq_file.c:182
 #1: ffff88801faed888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x55/0x3c0 fs/kernfs/file.c:112
 #2: ffff8880768ee830 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x75/0x3c0 fs/kernfs/file.c:113
 #3: ffff88805659f178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
 #3: ffff88805659f178 (&dev->mutex){....}-{3:3}, at: uevent_show+0x16c/0x320 drivers/base/core.c:2408
2 locks held by dhcpcd/3851:
 #0: ffffffff8d435d28 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x21b/0x700 net/socket.c:1229
 #1: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0xef/0x5d0 net/8021q/vlan.c:581
2 locks held by getty/3944:
 #0: ffff88802c6ae098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/0:10/4300:
 #0: ffff88802b645938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc900030bfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4120
3 locks held by kworker/0:19/4309:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc9000314fd00 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffff88805a8b6400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
3 locks held by kworker/1:6/4384:
 #0: ffff88802b645938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc900049efd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4120
4 locks held by syz-executor/5655:
 #0: ffffffff8d4aa630 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
 #1: ffffffff8d4aa488 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8d4aa488 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x161/0xfa0 net/netlink/genetlink.c:790
 #2: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_register_hw+0x239f/0x3a60 net/mac80211/main.c:1251
 #3: ffffffff8c1d4a08 (param_lock){+.+.}-{3:3}, at: ieee80211_rate_control_ops_get net/mac80211/rate.c:192 [inline]
 #3: ffffffff8c1d4a08 (param_lock){+.+.}-{3:3}, at: rate_control_alloc net/mac80211/rate.c:239 [inline]
 #3: ffffffff8c1d4a08 (param_lock){+.+.}-{3:3}, at: ieee80211_init_rate_ctrl_alg+0x171/0x5e0 net/mac80211/rate.c:983
6 locks held by syz-executor/5758:
 #0: ffff88807f1d2460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590
 #1: ffff88805be40888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287
 #2: ffff888023f8d1d8 (kn->active#363){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1fd/0x500 fs/kernfs/file.c:288
 #3: ffffffff8cd8ad28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x14c/0x770 drivers/net/netdevsim/bus.c:295
 #4: ffff88805659f178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
 #4: ffff88805659f178 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
 #5: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: devlink_nl_port_fill+0x346/0x8c0 net/core/devlink.c:995
4 locks held by syz-executor/5761:
 #0: ffff88807f1d2460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590
 #1: ffff88805cbc1888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287
 #2: ffff888023f8d2c0 (kn->active#362){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1fd/0x500 fs/kernfs/file.c:288
 #3: ffffffff8cd8ad28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd3/0x3a0 drivers/net/netdevsim/bus.c:344
4 locks held by syz-executor/5764:
 #0: ffff88807f1d2460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590
 #1: ffff88805bff6c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287
 #2: ffff888023f8d2c0 (kn->active#362){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1fd/0x500 fs/kernfs/file.c:288
 #3: ffffffff8cd8ad28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd3/0x3a0 drivers/net/netdevsim/bus.c:344
5 locks held by syz.2.74/5902:
 #0: ffff888024abd4f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1056
 #1: ffff8880761c8460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590
 #2: ffff88801b3cc488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287
 #3: ffff88801abbc918 (kn->active){++++}-{0:0}, at: kernfs_fop_write_iter+0x1fd/0x500 fs/kernfs/file.c:288
 #4: ffffffff8c1d4a08 (param_lock){+.+.}-{3:3}, at: kernel_param_lock kernel/params.c:598 [inline]
 #4: ffffffff8c1d4a08 (param_lock){+.+.}-{3:3}, at: param_attr_store+0xcb/0x300 kernel/params.c:583
1 lock held by syz-executor/5904:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5907:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5910:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5913:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5916:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5919:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5922:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5925:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5928:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5931:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/5934:
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d44d988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe1b/0xe60 kernel/hung_task.c:369
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4313 Comm: kworker/u4:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:168 [inline]
RIP: 0010:unwind_next_frame+0x1a6/0x1cf0 arch/x86/kernel/unwind_orc.c:448
Code: 46 ff 39 e8 0f 86 56 14 00 00 89 e8 4c 8d 24 85 5c fc 9e 8e 4c 89 e0 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 <84> c0 0f 85 dd 15 00 00 45 8b 24 24 89 e8 ff c0 4c 8d 2c 85 5c fc
RSP: 0018:ffffc9000319eef0 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffc9000319ef88 RCX: ffffffff962f5f00
RDX: dffffc0000000000 RSI: 0000000000090081 RDI: 0000000000000001
RBP: 00000000000064c6 R08: ffffc9000319f050 R09: 0000000000000002
R10: dffffc0000000000 R11: fffff52000633dfd R12: ffffffff8ea08f74
R13: ffffc9000319f300 R14: ffffffff8164c664 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb04289e000 CR3: 000000007dc52000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack+0x35/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348
 kvfree_call_rcu+0x105/0x7f0 kernel/rcu/tree.c:3600
 cfg80211_update_known_bss+0x184/0xb60 net/wireless/scan.c:-1
 cfg80211_bss_update+0x156/0x21a0 net/wireless/scan.c:1830
 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2552 [inline]
 cfg80211_inform_bss_frame_data+0x88d/0x1ed0 net/wireless/scan.c:2585
 ieee80211_bss_info_update+0x6ba/0xa80 net/mac80211/scan.c:190
 ieee80211_rx_bss_info net/mac80211/ibss.c:1123 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1614 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1763/0x2b50 net/mac80211/ibss.c:1643
 ieee80211_iface_process_skb net/mac80211/iface.c:1465 [inline]
 ieee80211_iface_work+0x714/0xc50 net/mac80211/iface.c:1519
 cfg80211_wiphy_work+0x224/0x260 net/wireless/core.c:433
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/20 07:18 linux-5.15.y 0eb903b5b519 1e72964b .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in netdev_run_todo
2026/08/15 05:06 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in netdev_run_todo
* Struck through repros no longer work on HEAD.