Re: [PATCH] drm/virtio: remove some redundant code

[Su Hui]

On 2023/7/12 14:36, Dan Carpenter wrote:

> On Wed, Jul 12, 2023 at 09:18:42AM +0800, Su Hui wrote:
> > On 2023/7/11 19:13, Dan Carpenter wrote:
> > > On Tue, Jul 11, 2023 at 05:00:31PM +0800, Su Hui wrote:
> > > > virtio_gpu_get_vbuf always be successful,
> > > > so remove the error judgment.
> > > No, just ignore the static checker false positive in this case.  The
> > > intent of the code is clear that if it did have an error it should
> > > return an error pointer.
> > Hi, Dan,
> >
> > Function "virtio_gpu_get_vbuf" call "kmem_cache_zalloc (vgdev->vbufs,
> > GFP_KERNEL | __GFP_NOFAIL)" to
> > allocate memory. Adding the " __GFP_NOFAIL”flag make sure it won't fail. And
> > "virtio_gpu_get_vbuf" never
> > return an error code, so I think this is not a false positive.
> We all see this and agree.
>
> However the check for if (IS_ERR()) is written deliberately because we
> might change the code to return error pointers in the future.  Static
> checkers are looking for code that does something unintentional but in
> this case the code was written that way deliberately.
Got it ,  I shouldn't remove it because the check may be useful in the 
future.
Thanks for your explanation.

Su Hui

> regards,
> dan carpenter