INFO: task can't die in netdev_run_todo

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    4993e4fe Add linux-next specific files for 20200814
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1181e1a6900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2055bd0d83d5ee16
dashboard link: https://syzkaller.appspot.com/bug?extid=22a310041c3467f85d12
compiler:       gcc (GCC) 10.1.0-syz 20200507
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=145b6aa6900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+22a310041c3467f85d12@xxxxxxxxxxxxxxxxxxxxxxxxx

INFO: task syz-executor.1:8005 can't die for more than 143 seconds.
syz-executor.1  D25048  8005      1 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
 __mutex_lock_common kernel/locking/mutex.c:1033 [inline]
 __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
 netdev_run_todo+0x705/0xac0 net/core/dev.c:10104
 sit_exit_batch_net+0x4ad/0x6c0 net/ipv6/sit.c:1945


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