syzbot


INFO: task hung in netdev_run_todo (4)

Status: upstream: reported on 2024/10/09 19:06
Subsystems: wireguard
[Documentation on labels]
Reported-by: syzbot+894cca71fa925aabfdb2@syzkaller.appspotmail.com
First crash: 341d, last: 2d04h
Discussions (4)
Title Replies (including bot) Last reply
[syzbot] Monthly wireguard report (May 2025) 0 (1) 2025/05/12 06:34
[syzbot] Monthly wireguard report (Feb 2025) 0 (1) 2025/02/26 15:11
[syzbot] Monthly wireguard report (Dec 2024) 0 (1) 2024/12/26 09:01
[syzbot] [net?] INFO: task hung in netdev_run_todo (4) 0 (1) 2024/10/09 19:06
Similar bugs (13)
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 993d 1309d 0/1 auto-obsoleted due to no activity on 2023/03/07 08:19
upstream INFO: task hung in netdev_run_todo net 1 12 2167d 2721d 0/29 closed as invalid on 2019/10/23 07:29
linux-4.19 INFO: task hung in netdev_run_todo (2) 1 3 1800d 1847d 0/1 auto-closed as invalid on 2020/12/20 04:57
android-44 INFO: task hung in netdev_run_todo 1 1 2661d 2661d 0/2 auto-closed as invalid on 2019/02/22 12:49
linux-4.19 INFO: task hung in netdev_run_todo 1 1 2126d 2126d 0/1 auto-closed as invalid on 2020/01/29 06:48
upstream INFO: task hung in netdev_run_todo (3) net 1 24 404d 441d 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 639d 639d 0/3 auto-obsoleted due to no activity on 2024/02/04 09:09
upstream INFO: task hung in netdev_run_todo (2) staging wireguard usb 1 C error 241 530d 1686d 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 2653d 2653d 0/3 auto-closed as invalid on 2019/02/22 14:57
linux-4.14 INFO: task hung in netdev_run_todo 1 1 986d 986d 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 59 3d15h 35d 0/1 premoderation: reported on 2025/06/22 07:19
linux-5.15 INFO: task hung in netdev_run_todo (2) 1 54 251d 432d 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 1409d 1802d 0/29 auto-obsoleted due to no activity on 2023/04/16 04:59

Sample crash report:
INFO: task syz-executor:5865 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc7-syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:20360 pid:5865  tgid:5865  ppid:1      task_flags:0x40054c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
 netdev_run_todo+0x327/0xea0 net/core/dev.c:11376
 tun_detach drivers/net/tun.c:639 [inline]
 tun_chr_close+0x13c/0x1c0 drivers/net/tun.c:3396
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x22e0 kernel/exit.c:964
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e5f98d3bc
RSP: 002b:00007f8e5fcdfd80 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f8e5f98d3bc
RDX: 0000000000000030 RSI: 00007f8e5fcdfe40 RDI: 00000000000000f9
RBP: 00007f8e5fcdfdec R08: 0000000000000000 R09: 0079746972756365
R10: 00007f8e5fb837e0 R11: 0000000000000246 R12: 0000000000000040
R13: 00005555854f3590 R14: 000000000003709e R15: 00007f8e5fcdfe40
 </TASK>
INFO: task syz-executor:5867 blocked for more than 144 seconds.
      Not tainted 6.16.0-rc7-syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21592 pid:5867  tgid:5867  ppid:1      task_flags:0x40054c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
 netdev_run_todo+0x327/0xea0 net/core/dev.c:11376
 tun_detach drivers/net/tun.c:639 [inline]
 tun_chr_close+0x13c/0x1c0 drivers/net/tun.c:3396
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x22e0 kernel/exit.c:964
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e72d8d3bc
RSP: 002b:00007f4e730dfd80 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007f4e72d8d3bc
RDX: 0000000000000030 RSI: 00007f4e730dfe40 RDI: 00000000000000f9
RBP: 00007f4e730dfdec R08: 0000000000000000 R09: 0079746972756365
R10: 00007f4e72f837e0 R11: 0000000000000246 R12: 000000000000004d
R13: 00000000000927c0 R14: 000000000003427e R15: 00007f4e730dfe40
 </TASK>
INFO: task syz.4.328:7140 blocked for more than 145 seconds.
      Not tainted 6.16.0-rc7-syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.328       state:D stack:25304 pid:7140  tgid:7138  ppid:5866   task_flags:0x40044c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
 netdev_run_todo+0x327/0xea0 net/core/dev.c:11376
 tun_detach drivers/net/tun.c:639 [inline]
 tun_chr_close+0x13c/0x1c0 drivers/net/tun.c:3396
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x22e0 kernel/exit.c:964
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0d0458e9a9
RSP: 002b:00007f0d0548b038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007f0d047b6080 RCX: 00007f0d0458e9a9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f0d04610d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f0d047b6080 R15: 00007f0d048dfa28
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by kworker/u8:5/135:
2 locks held by getty/5606:
 #0: ffff8880354020a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5865:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz-executor/5867:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
2 locks held by kworker/1:4/5913:
2 locks held by kworker/1:5/5936:
6 locks held by kworker/0:7/5981:
1 lock held by syz.4.328/7140:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz.2.330/7144:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
6 locks held by kworker/u8:9/7173:
 #0: ffff88801b2fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801b2fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc9000b827bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000b827bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffffffff8f50f510 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
 #3: ffff88805627e0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
 #3: ffff88805627e0e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
 #3: ffff88805627e0e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
 #4: ffff888035165250 (&devlink->lock_key#4){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
 #4: ffff888035165250 (&devlink->lock_key#4){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
 #4: ffff888035165250 (&devlink->lock_key#4){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
 #5: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
2 locks held by kworker/1:9/7175:
2 locks held by kworker/1:10/7179:
1 lock held by syz-executor/7191:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz-executor/7193:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz-executor/7194:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz-executor/7197:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz-executor/7199:
 #0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
4 locks held by syz-executor/7278:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88802994c088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: 
ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7281:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88802797a088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
7 locks held by syz-executor/7285:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888057dc7088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}
, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
 #4: ffff8880223c50e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
 #4: ffff8880223c50e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
 #4: ffff8880223c50e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292
 #5: ffff8880223c4250 (&devlink->lock_key#6){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675
 #6: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
4 locks held by syz-executor/7288:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888038d25888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7291:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88802faa8888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7331:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888089d61088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7338:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888087116488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7339:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888084b62c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7348:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888027fce488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7352:
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888032154428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88803fc3d088 (&of->mutex){+.+.}-{4:4}
, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff888026d84a58 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8eda9908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:470
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 24 Comm: kworker/1:0 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events nsim_dev_hwstats_traffic_work
RIP: 0010:lockdep_hardirqs_on+0xa7/0x150 kernel/locking/lockdep.c:4476
Code: 0a 00 00 48 3b 83 e0 0a 00 00 0f 85 80 00 00 00 49 89 fe 48 c7 c7 11 64 99 8d e8 44 19 00 00 65 c7 05 e1 72 32 07 01 00 00 00 <4c> 89 b3 90 0a 00 00 8b 83 88 0a 00 00 ff c0 89 83 88 0a 00 00 89
RSP: 0018:ffffc90000a078f8 EFLAGS: 00000082
RAX: 0000000000000001 RBX: ffff88801d6c8000 RCX: 5e716813f4a0a700
RDX: 0000000000000002 RSI: ffffffff8d996411 RDI: ffffffff8be28d00
RBP: ffffc90000a079a0 R08: ffffffff8fa1dcf7 R09: 1ffffffff1f43b9e
R10: dffffc0000000000 R11: fffffbfff1f43b9f R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff8b702635 R15: 1ffff92000140f24
FS:  0000000000000000(0000) GS:ffff888125d23000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48619a0263 CR3: 0000000033fa0000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
 _raw_spin_unlock_irqrestore+0x85/0x110 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 backlog_unlock_irq_restore net/core/dev.c:252 [inline]
 enqueue_to_backlog+0xa45/0xfa0 net/core/dev.c:5180
 netif_rx_internal+0x130/0x560 net/core/dev.c:5491
 __netif_rx+0x78/0xc0 net/core/dev.c:5511
 loopback_xmit+0x47a/0x6f0 drivers/net/loopback.c:90
 __netdev_start_xmit include/linux/netdevice.h:5215 [inline]
 netdev_start_xmit include/linux/netdevice.h:5224 [inline]
 xmit_one net/core/dev.c:3830 [inline]
 dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3846
 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4713
 dev_queue_xmit include/linux/netdevice.h:3355 [inline]
 neigh_hh_output include/net/neighbour.h:523 [inline]
 neigh_output include/net/neighbour.h:537 [inline]
 ip_finish_output2+0xd03/0x1160 net/ipv4/ip_output.c:235
 synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
 nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623
 nf_hook include/linux/netfilter.h:272 [inline]
 NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315
 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:317
 __netif_receive_skb_one_core net/core/dev.c:5977 [inline]
 __netif_receive_skb+0x143/0x380 net/core/dev.c:6090
 process_backlog+0x60e/0x14f0 net/core/dev.c:6442
 __napi_poll+0xc7/0x480 net/core/dev.c:7414
 napi_poll net/core/dev.c:7478 [inline]
 net_rx_action+0x707/0xe30 net/core/dev.c:7605
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:queue_delayed_work_on+0x201/0x280 kernel/workqueue.c:2566
Code: 4d 85 e4 75 16 e8 2f 3b 35 00 eb 15 e8 28 3b 35 00 e8 73 ad e2 09 4d 85 e4 74 ea e8 19 3b 35 00 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 66 43 c7 44 2f 09 00 00 43 c6 44 2f 0b 00
RSP: 0018:ffffc900001e7980 EFLAGS: 00000293
RAX: ffffffff818aebb7 RBX: ffff88807cf03501 RCX: ffff88801d6c8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900001e7a70 R08: ffffffff8fa1dcf7 R09: 1ffffffff1f43b9e
R10: dffffc0000000000 R11: fffffbfff1f43b9f R12: 0000000000000200
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff9200003cf38
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (434):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/23 00:37 upstream 89be9a83ccf1 85deaf45 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in netdev_run_todo
2025/07/21 21:41 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/21 19:22 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/21 13:53 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/21 13:53 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/20 09:19 upstream bf61759db409 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/19 21:31 upstream bf61759db409 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/19 07:34 upstream 4871b7cb27f4 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/18 11:21 upstream 6832a9317eee f550e092 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/18 05:11 upstream 6832a9317eee 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/17 03:41 upstream e2291551827f 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/16 22:16 upstream 155a3c003e55 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/16 04:18 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/14 22:13 upstream 347e9f5043c8 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/14 10:04 upstream 347e9f5043c8 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/13 13:52 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/13 00:33 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/13 00:32 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/11 16:10 upstream bc9ff192a6c9 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/10 11:46 upstream 8c2e52ebbe88 19d4829f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/10 03:36 upstream 8c2e52ebbe88 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/09 14:13 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/09 08:23 upstream 733923397fd9 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/08 16:29 upstream d7b8f8e20813 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/08 14:47 upstream d7b8f8e20813 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/07 14:38 upstream d7b8f8e20813 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/04 19:50 upstream 4c06e63b9203 d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/02 19:24 upstream b4911fb0b060 0cd59a8f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/02 13:11 upstream 66701750d556 0cd59a8f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/01 13:19 upstream 66701750d556 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/01 02:08 upstream 66701750d556 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/30 20:50 upstream d0b3b7b22dfa 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/29 18:11 upstream afa9a6f4f574 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/29 01:39 upstream dfba48a70cb6 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/28 20:58 upstream aaf724ed6926 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/28 18:38 upstream aaf724ed6926 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/28 14:22 upstream 35e261cd95dd fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in netdev_run_todo
2025/06/28 01:23 upstream 35e261cd95dd 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in netdev_run_todo
2025/06/27 20:55 upstream 67a993863163 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in netdev_run_todo
2025/06/10 03:01 upstream 19272b37aa4f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in netdev_run_todo
2024/10/13 22:33 upstream ba01565ced22 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in netdev_run_todo
2024/10/06 16:49 upstream 8f602276d390 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in netdev_run_todo
2024/09/27 16:51 upstream 075dbe9f6e3c 2b1784d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in netdev_run_todo
2025/07/06 03:02 upstream 05df91921da6 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in netdev_run_todo
2025/02/25 10:53 upstream d082ecbc71e9 d34966d1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-compat INFO: task hung in netdev_run_todo
2024/09/21 15:34 upstream 1868f9d0260e 6f888b75 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 INFO: task hung in netdev_run_todo
2025/05/22 18:47 net 3fab2d2d901a 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in netdev_run_todo
2025/06/11 07:25 net-next c09ef59e17c6 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in netdev_run_todo
2025/07/01 18:35 linux-next 1343433ed389 ffe4b334 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in netdev_run_todo
2025/07/25 04:58 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 fb8f743d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/24 16:48 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 65d60d73 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/24 04:18 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 0c1d6ded .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/22 03:24 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 1555463b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/18 01:14 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 88248e14 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/17 13:39 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 89164500 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/15 02:33 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 03fcfc4b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/14 14:06 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 d8fc7335 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/04 16:29 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 d869b261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/04 04:44 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 76ad128c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/07/03 15:59 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 a3c808e4 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
2025/06/30 18:59 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next fda589c28604 6e83b42d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 INFO: task hung in netdev_run_todo
* Struck through repros no longer work on HEAD.