[drm/ttm] Memory corruption problem when ttm_tt_init() fails.

hi

I've encountered [BUG: unable to handle kernel NULL pointer dereference at] which has call stack like your pattern2. And before this happended, I got a lot of memory allocation failure warnings. And my kernel is 3.10.0-327.62.1.el7.x86_64.

Since, you mentioned it may be a bug of drm/tmm. So, I checked drm/ttm for possible patch to fix this problem, but found nothing. Could you please tell me is there any progress of this problem that you detected.

Best wished!

Jinxiang, Gu