diff --git a/[refs] b/[refs]
index feed5aace651..5862457eb4ab 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: de12d44fcad409e1b2956ef0ffd48818423fc701
+refs/heads/master: 497a3ff9877424108020c7091c7886b364c0486e
diff --git a/trunk/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/trunk/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 1a4c84cecca7..c14eb764e096 100644
--- a/trunk/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/trunk/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -706,6 +706,10 @@ static struct drm_framebuffer_funcs vmw_framebuffer_dmabuf_funcs = {
 	.create_handle = vmw_framebuffer_create_handle,
 };
 
+/**
+ * We need to reserve the start of vram because the host might
+ * scribble to it at mode changes, so we need to reserve it.
+ */
 static int vmw_surface_dmabuf_pin(struct vmw_framebuffer *vfb)
 {
 	struct vmw_private *dev_priv = vmw_priv(vfb->base.dev);
@@ -729,6 +733,9 @@ static int vmw_surface_dmabuf_pin(struct vmw_framebuffer *vfb)
 	return ret;
 }
 
+/**
+ * See vmw_surface_dmabuf_pin.
+ */
 static int vmw_surface_dmabuf_unpin(struct vmw_framebuffer *vfb)
 {
 	struct ttm_buffer_object *bo;
@@ -745,6 +752,9 @@ static int vmw_surface_dmabuf_unpin(struct vmw_framebuffer *vfb)
 	return 0;
 }
 
+/**
+ * Pin the dmabuffer to the start of vram.
+ */
 static int vmw_framebuffer_dmabuf_pin(struct vmw_framebuffer *vfb)
 {
 	struct vmw_private *dev_priv = vmw_priv(vfb->base.dev);