drm/ttm: Handle in-memory region copies

commit 9a0599ddeae012a771bba5e23393fc52d8a59d89 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index af894584dd90..068341ad1f5f 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -347,7 +347,9 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
         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