syzbot has bisected this bug to:
commit cbb537634780172137459dead490d668d437ef4d
Author: Jens Axboe <axboe@xxxxxxxxx>
Date: Mon Dec 9 18:22:50 2019 +0000
io_uring: avoid ring quiesce for fixed file set unregister and update
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10eadc56e00000
start commit: 7ddd09fc Add linux-next specific files for 20191220
git tree: linux-next
final crash: https://syzkaller.appspot.com/x/report.txt?x=12eadc56e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=14eadc56e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=f183b01c3088afc6
dashboard link: https://syzkaller.appspot.com/bug?extid=6bf913476056cb0f8d13
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15653c3ee00000
Reported-by: syzbot+6bf913476056cb0f8d13@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: cbb537634780 ("io_uring: avoid ring quiesce for fixed file set
unregister and update")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection