[PATCH] drm/gk20a/fb: fix NULL dereference

[Alexandre Courbot]

gk20a_ram_put() can be called with a NULL nouveau_mem in case of error.
Handle that case the way is it done in other RAM drivers.

Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
---
 drivers/gpu/drm/nouveau/core/subdev/fb/ramgk20a.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/nouveau/core/subdev/fb/ramgk20a.c b/drivers/gpu/drm/nouveau/core/subdev/fb/ramgk20a.c
index 403c88f07b99..7effd1a63458 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/fb/ramgk20a.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/fb/ramgk20a.c
@@ -36,6 +36,8 @@ gk20a_ram_put(struct nouveau_fb *pfb, struct nouveau_mem **pmem)
 	int i;
 
 	*pmem = NULL;
+	if (unlikely(mem == NULL))
+		return;
 
 	for (i = 0; i < mem->size; i++) {
 		struct page *page;
-- 
1.9.2