Re: [PATCH] drm/vmwgfx: Zero initialize handle in vmw_execbuf_process

From: Deepak Singh Rawat
Date: Mon Mar 11 2019 - 13:00:44 EST


Hi Nathan,

Thanks for doing this. I will include this in vmwgfx-next.

Reviewed-by: Deepak Rawat <drawat@xxxxxxxxxx>

On Thu, 2019-03-07 at 15:26 -0700, Nathan Chancellor wrote:
> When building with -Wsometimes-uninitialized, Clang warns:
>
> drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c:3964:7: warning: variable
> 'handle' is used uninitialized whenever '?:' condition is false
> [-Wsometimes-uninitialized]
>
> It's not wrong; however, in practice, this is never an issue because
> the value of handle isn't used when user_fence_rep is NULL because
> vmw_execbuf_copy_fence_user returns immediately when that is the
> case.
> Just zero initialize this variable so that Clang no longer warns.
>
> Link:
> https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2FClangBuiltLinux%2Flinux%2Fissues%2F397&amp;data=02%7C01%7Cdrawat%40vmware.com%7C6b9c429d16d844a5740c08d6a34bedb4%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C636875943916412703&amp;sdata=Yf7%2BzrbZS96yNJQewYQQ7YsHUDtJSvPaomyTJFZjsDk%3D&amp;reserved=0
> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> ---
> drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> index 88b8178d4687..4ba06c2828a1 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> @@ -3829,7 +3829,7 @@ int vmw_execbuf_process(struct drm_file
> *file_priv,
> struct vmw_sw_context *sw_context = &dev_priv->ctx;
> struct vmw_fence_obj *fence = NULL;
> struct vmw_cmdbuf_header *header;
> - uint32_t handle;
> + uint32_t handle = 0;
> int ret;
> int32_t out_fence_fd = -1;
> struct sync_file *sync_file = NULL;