Re: [PATCH] drm/nouveau/bios: set info only when the return is not 0

[Tom Rix]

On 7/15/22 12:09 PM, Lyude Paul wrote:
> On Mon, 2022-07-04 at 17:32 -0400, Lyude Paul wrote:
> > Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
> >
> > Currently on flakey internet in the back of a car, so I probably won't be
> > able
> > to push this until I get back tonight or early tomorrow
> Whoops! Slipped my mind when I got back, but I just remembered it now so I
> will go ahead and push :). apologies for the delay!

Thanks!

T

> > On Sat, 2022-07-02 at 11:39 -0400, Tom Rix wrote:
> > > clang static analysis reports
> > > drivers/gpu/drm/nouveau/nvkm/subdev/bios/pmu.c:68:17: warning: The right
> > > operand of '*' is a garbage value [core.UndefinedBinaryOperatorResult]
> > >          switch (!!data * *ver) {
> > >                         ^ ~~~~
> > > A switch statement with only a default should be reduced to an if.
> > >
> > > If nvbios_pmuEp() returns 0, via the data variable, the output info
> > > parameter
> > > is not used.  So set info only when data is not 0.
> > >
> > > The struct nvbios_pmuE only has the type and data elements.  Since both of
> > > these
> > > are explicitly set, memset is not needed.  So remove it.
> > >
> > > Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
> > > ---
> > >   drivers/gpu/drm/nouveau/nvkm/subdev/bios/pmu.c | 5 +----
> > >   1 file changed, 1 insertion(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/pmu.c
> > > b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/pmu.c
> > > index b4a308f3cf7b..49e2664a734c 100644
> > > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/pmu.c
> > > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/pmu.c
> > > @@ -64,12 +64,9 @@ nvbios_pmuEp(struct nvkm_bios *bios, int idx, u8 *ver,
> > > u8
> > > *hdr,
> > >               struct nvbios_pmuE *info)
> > >   {
> > >          u32 data = nvbios_pmuEe(bios, idx, ver, hdr);
> > > -       memset(info, 0x00, sizeof(*info));
> > > -       switch (!!data * *ver) {
> > > -       default:
> > > +       if (data) {
> > >                  info->type = nvbios_rd08(bios, data + 0x00);
> > >                  info->data = nvbios_rd32(bios, data + 0x02);
> > > -               break;
> > >          }
> > >          return data;
> > >   }