syzbot has bisected this issue to:
commit 5c074eeabbd332b11559f7fc1e89d456f94801fb
Author: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Date: Wed Nov 14 12:20:29 2018 +0000
udmabuf: set read/write flag when exporting
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12b21bbfa80000
start commit: db906f0ca6bb Merge tag 'phy-for-6.6' of git://git.kernel.o..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=11b21bbfa80000
console output: https://syzkaller.appspot.com/x/log.txt?x=16b21bbfa80000
kernel config: https://syzkaller.appspot.com/x/.config?x=3bd57a1ac08277b0
dashboard link: https://syzkaller.appspot.com/bug?extid=17a207d226b8a5fb0fd9
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11609f38680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14c1fc00680000
Reported-by: syzbot+17a207d226b8a5fb0fd9@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 5c074eeabbd3 ("udmabuf: set read/write flag when exporting")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
