Re: general protection fault in syscall_return_slowpath

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 033724d6864245a11f8e04c066002e6ad22b3fd0
Author: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Date:   Wed Jul 15 01:51:02 2020 +0000

    fbdev: Detect integer underflow at "struct fbcon_ops"->clear_margins.

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=13f979f6900000
start commit:   63623fd4 Merge tag 'for-linus' of git://git.kernel.org/pub..
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=5d2e033af114153f
dashboard link: https://syzkaller.appspot.com/bug?extid=cd66e43794b178bb5cd6
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12a42329e00000

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

#syz fix: fbdev: Detect integer underflow at "struct fbcon_ops"->clear_margins.

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