syzbot suspects this issue was fixed by commit:

commit f671a691e299f58835d4660d642582bf0e8f6fda
Author: Desmond Cheong Zhi Xi [off-list ref]
Date:   Fri Jul 2 09:18:30 2021 +0000

    fcntl: fix potential deadlocks for &fown_struct.lock

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15fa8017300000
start commit:   293837b9ac8d Revert "i915: fix remap_io_sg to verify the p..
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=18fade5827eb74f7
dashboard link: https://syzkaller.appspot.com/bug?extid=8073030e235a5a84dd31
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=171390add00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10050553d00000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: fcntl: fix potential deadlocks for &fown_struct.lock

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