Hello,

syzbot has tested the proposed patch and the reproducer did not trigger  
crash:

Reported-and-tested-by:  
syzbot+e1a1577ca8bcb47b769a@syzkaller.appspotmail.com

Note: the tag will also help syzbot to understand when the bug is fixed.

Tested on upstream commit
4bf772b14675411a69b3c807f73006de0fe4b649 (Fri Feb 2 01:48:47 2018 +0000)
Merge tag 'drm-for-v4.16' of git://people.freedesktop.org/~airlied/linux

compiler: gcc (GCC) 7.1.1 20170620
Patch is attached.
Kernel config is attached.


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