Re: [PATCH] drm: remove redundant assignment to variable 'ret'

[Jing Xiangfeng]

On 2020/7/15 20:05, Daniel Vetter wrote:
> On Wed, Jul 15, 2020 at 03:05:59PM +0800, Jing Xiangfeng wrote:
> > The variable ret has been assigned the value '-EINVAL'. The assignment
> > in the if() is redundant. We can remove it.
>
> Nope, that's not correct. Before this assignement ret is guaranteed to be
> 0.

Before this assignment ret is '-EINVAL'(see commit 45bc3d26c95a: "drm: 
rework SET_MASTER and DROP_MASTER perm handling"). It is set to 0 above
around the drm_drop_master() calls.

Thanks
> -Daniel
>
> > Signed-off-by: Jing Xiangfeng <jingxiangfeng@xxxxxxxxxx>
> > ---
> >   drivers/gpu/drm/drm_auth.c | 1 -
> >   1 file changed, 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/drm_auth.c b/drivers/gpu/drm/drm_auth.c
> > index 800ac39f3213..6e1b502f2797 100644
> > --- a/drivers/gpu/drm/drm_auth.c
> > +++ b/drivers/gpu/drm/drm_auth.c
> > @@ -299,7 +299,6 @@ int drm_dropmaster_ioctl(struct drm_device *dev, void *data,
> >
> >   	if (file_priv->master->lessor != NULL) {
> >   		DRM_DEBUG_LEASE("Attempt to drop lessee %d as master\n", file_priv->master->lessee_id);
> > -		ret = -EINVAL;
> >   		goto out_unlock;
> >   	}
> >
> > --
> > 2.17.1