[PATCH] drm/vmwgfx: clean up some error pointer checking

[Dan Carpenter]

The vmw_user_bo_noref_lookup() function cannot return NULL.  If it
could, then this function would return PTR_ERR(NULL) which is success.
Returning success without initializing "*vmw_bo_p = vmw_bo;" would
lead to an uninitialized variable bug in the caller.  Smatch complains
about this:

drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c:1177 vmw_translate_mob_ptr() warn: 
passing zero to 'PTR_ERR'
drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c:1314 vmw_cmd_dx_bind_query() error: 
uninitialized symbol 'vmw_bo'.

Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c 
b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index d49de4905efa..f085dbd4736d 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -1172,7 +1172,7 @@ static int vmw_translate_mob_ptr(struct vmw_private 
*dev_priv,
 
        vmw_validation_preload_bo(sw_context->ctx);
        vmw_bo = vmw_user_bo_noref_lookup(sw_context->filp, handle);
-       if (IS_ERR_OR_NULL(vmw_bo)) {
+       if (IS_ERR(vmw_bo)) {
                VMW_DEBUG_USER("Could not find or use MOB buffer.\n");
                return PTR_ERR(vmw_bo);
        }
@@ -1226,7 +1226,7 @@ static int vmw_translate_guest_ptr(struct vmw_private 
*dev_priv,
 
        vmw_validation_preload_bo(sw_context->ctx);
        vmw_bo = vmw_user_bo_noref_lookup(sw_context->filp, handle);
-       if (IS_ERR_OR_NULL(vmw_bo)) {
+       if (IS_ERR(vmw_bo)) {
                VMW_DEBUG_USER("Could not find or use GMR region.\n");
                return PTR_ERR(vmw_bo);
        }
-- 
2.35.1