Hi Kieran,
Thanks for the feedback.
> Subject: Re: [PATCH 1/2] media: v4l: vsp1: Fix bru null pointer access
>
> Hi Biju,
>
> On 01/03/2021 12:08, Biju Das wrote:
> > RZ/G2L SoC has only BRS. This patch fixes null pointer access,when
> > only BRS is enabled.
> >
> > Fixes: cbb7fa49c7466("media: v4l: vsp1: Rename BRU to BRx")
> > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > ---
> > drivers/media/platform/vsp1/vsp1_drm.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/media/platform/vsp1/vsp1_drm.c
> > b/drivers/media/platform/vsp1/vsp1_drm.c
> > index 86d5e3f4b1ff..f6d2f47a4058 100644
> > --- a/drivers/media/platform/vsp1/vsp1_drm.c
> > +++ b/drivers/media/platform/vsp1/vsp1_drm.c
> > @@ -245,7 +245,7 @@ static int vsp1_du_pipeline_setup_brx(struct
> vsp1_device *vsp1,
> > brx = &vsp1->bru->entity;
> > else if (pipe->brx && !drm_pipe->force_brx_release)
> > brx = pipe->brx;
> > - else if (!vsp1->bru->entity.pipe)
> > + else if (vsp1_feature(vsp1, VSP1_HAS_BRU) &&
> > +!vsp1->bru->entity.pipe)
> > brx = &vsp1->bru->entity;
> > else
> > brx = &vsp1->brs->entity;
>
>
> The comments here describe that the choice to start at the BRU is
> arbitrary, so if we could confirm that there will always be a BRS
> otherwise, we could swap those to save an extra feature check.
As long as we are supporting composition(Multiple inputs with Blend and Raster operations)
There will be either BRU or BRS or both in R-Car Gen3|RZ/G2 SoC's. Currently this is
the case with all SoC variant of this families.
Cheers,
Biju
>
> But as we have both vsp1_feature(vsp1, VSP1_HAS_BRU) and
> vsp1_feature(vsp1, VSP1_HAS_BRS), I don't think that's the case.
>
> I'd almost want to check for vsp1_feature(vsp1, VSP1_HAS_BRS) on the
> brs->entity line to keep the symmetry ... but it wouldn't be needed, as
> it should fall through. If there isn't a BRS there must be a BRU or we
> wouldn't be setting up a brx in the first place ;-)
>
> So I think what you have is good.
>
> Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
