[PATCH] drm/vmwgfx: Fix an error return check in vmw_compat_shader_add()

[Haoxiang Li]

In vmw_compat_shader_add(), the return value check of vmw_shader_alloc()
is not proper. Modify the check for the return pointer 'res'.

Found by code review and compiled on ubuntu 20.04.

Fixes: 18e4a4669c50 ("drm/vmwgfx: Fix compat shader namespace")
Cc: sta...@vger.kernel.org
Signed-off-by: Haoxiang Li <lihaoxi...@isrc.iscas.ac.cn>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_shader.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c 
b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
index 69dfe69ce0f8..7ed938710342 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
@@ -923,8 +923,10 @@ int vmw_compat_shader_add(struct vmw_private *dev_priv,
        ttm_bo_unreserve(&buf->tbo);
 
        res = vmw_shader_alloc(dev_priv, buf, size, 0, shader_type);
-       if (unlikely(ret != 0))
+       if (IS_ERR(res)) {
+               ret = PTR_ERR(res);
                goto no_reserve;
+       }
 
        ret = vmw_cmdbuf_res_add(man, vmw_cmdbuf_res_shader,
                                 vmw_shader_key(user_key, shader_type),
-- 
2.25.1