syzbot has bisected this issue to:
commit 6a3c7f5c87854e948c3c234e5f5e745c7c553722
Author: Nikolay Borisov <nborisov@xxxxxxxx>
Date: Thu May 28 08:05:13 2020 +0000
btrfs: don't balance btree inode pages from buffered write path
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14f973c2900000
start commit: 5631c5e0 Merge tag 'xfs-5.9-merge-7' of git://git.kernel.o..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=16f973c2900000
console output: https://syzkaller.appspot.com/x/log.txt?x=12f973c2900000
kernel config: https://syzkaller.appspot.com/x/.config?x=afba7c06f91e56eb
dashboard link: https://syzkaller.appspot.com/bug?extid=7b1677fecb5976b0a099
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=155d73fa900000
Reported-by: syzbot+7b1677fecb5976b0a099@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 6a3c7f5c8785 ("btrfs: don't balance btree inode pages from buffered write path")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
