syzbot has bisected this bug to:

commit 0e034f5c4bc408c943f9c4a06244415d75d7108c
Author: Linus Torvalds [off-list ref]
Date:   Wed May 18 18:51:25 2016 +0000

     iwlwifi: fix mis-merge that breaks the driver

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=10f955f0600000
start commit:   3bfe1fc4 Merge tag 'for-5.3/dm-changes-2' of git://git.ker..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=12f955f0600000
console output: https://syzkaller.appspot.com/x/log.txt?x=14f955f0600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dcfc65ee492509c6
dashboard link: https://syzkaller.appspot.com/bug?extid=ad8ca40ecd77896d51e2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=135cbed0600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14dd4e34600000

Reported-by: syzbot+ad8ca40ecd77896d51e2@syzkaller.appspotmail.com
Fixes: 0e034f5c4bc4 ("iwlwifi: fix mis-merge that breaks the driver")

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