commit 9a0599ddeae012a771bba5e23393fc52d8a59d89
author Jakob Bornecrantz <jakob@vmware.com> Wed Oct 30 02:46:56 2013 -0700
committer Thomas Hellstrom <thellstrom@vmware.com> Wed Nov 06 04:35:58 2013 -0800
tree 378cc851a1bbdbded9b73f47eaa946ad1b01446d
parent 15205fbcbe5abf52d6b064c5e8d2f901518d14a2

drm/ttm: Handle in-memory region copies

Fix the case where the ttm pointer may be NULL causing
a NULL pointer dereference.

Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Thomas Hellström <thellstrom@vmware.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/ttm/ttm_bo_util.c

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 7cc904d..8369e35c 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -348,7 +348,9 @@
 	if (old_iomap == NULL && ttm == NULL)
 		goto out2;
 
-	if (ttm->state == tt_unpopulated) {
+	/* TTM might be null for moves within the same region.
+	 */
+	if (ttm && ttm->state == tt_unpopulated) {
 		ret = ttm->bdev->driver->ttm_tt_populate(ttm);
 		if (ret) {
 			/* if we fail here don't nuke the mm node