syzbot has bisected this bug to: commit c0d9271ecbd891cdeb0fad1edcdd99ee717a655f Author: Yong Zhao <Yong.Zhao@xxxxxxx> Date: Fri Feb 1 23:36:21 2019 +0000 drm/amdgpu: Delete user queue doorbell variables bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1433ece4a00000 start commit: f49aa1de Merge tag 'for-5.2-rc1-tag' of git://git.kernel.o.. git tree: net-next final crash: https://syzkaller.appspot.com/x/report.txt?x=1633ece4a00000 console output: https://syzkaller.appspot.com/x/log.txt?x=1233ece4a00000 kernel config: https://syzkaller.appspot.com/x/.config?x=fc045131472947d7 dashboard link: https://syzkaller.appspot.com/bug?extid=94cc2a66fc228b23f360 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=163731f8a00000 Reported-by: syzbot+94cc2a66fc228b23f360@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: c0d9271ecbd8 ("drm/amdgpu: Delete user queue doorbell variables") For information about bisection process see: https://goo.gl/tpsmEJ#bisection