Re: possible deadlock in kill_fasync

[syzbot]

syzbot has bisected this issue to:

commit e918188611f073063415f40fae568fa4d86d9044
Author: Boqun Feng <boqun.feng@xxxxxxxxx>
Date:   Fri Aug 7 07:42:20 2020 +0000

    locking: More accurate annotations for read_lock()

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=10b46429500000
start commit:   7c8ca812 Add linux-next specific files for 20201117
git tree:       linux-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=12b46429500000
console output: https://syzkaller.appspot.com/x/log.txt?x=14b46429500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ff4bc71371dc5b13
dashboard link: https://syzkaller.appspot.com/bug?extid=3e12e14ee01b675e1af2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14b1dba6500000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12de8636500000

Reported-by: syzbot+3e12e14ee01b675e1af2@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: e918188611f0 ("locking: More accurate annotations for read_lock()")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection