unregister_netdevice: waiting for DEV to become free (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    18445bf4 Merge tag 'spi-fix-v5.9-rc1' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1710d97a900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=bb68b9e8a8cc842f
dashboard link: https://syzkaller.appspot.com/bug?extid=df400f2f24a1677cd7e0
compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15859986900000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1228fea1900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+df400f2f24a1677cd7e0@xxxxxxxxxxxxxxxxxxxxxxxxx

unregister_netdevice: waiting for lo to become free. Usage count = 1


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