Re: [PATCH] drm/i915/selftests: fix an error code in copy()

Andi Shyti
2023-05-26T14:52:42Z

Hi Dan,

On Fri, May 26, 2023 at 04:14:25PM +0300, Dan Carpenter wrote:
> On Fri, May 26, 2023 at 02:58:01PM +0200, Andi Shyti wrote:
> > Hi Dan,
> >
> > On Fri, May 26, 2023 at 02:59:31PM +0300, Dan Carpenter wrote:
> > > Return the error code if i915_gem_object_create_internal() fails,
> > > instead of returning success.
> > >
> > > Fixes: cf586021642d ("drm/i915/gt: Pipelined page migration")
> > > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> > > ---
> > > drivers/gpu/drm/i915/gt/selftest_migrate.c | 4 +++-
> > > 1 file changed, 3 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/gt/selftest_migrate.c b/drivers/gpu/drm/i915/gt/selftest_migrate.c
> > > index e677f2da093d..a26429fd5326 100644
> > > --- a/drivers/gpu/drm/i915/gt/selftest_migrate.c
> > > +++ b/drivers/gpu/drm/i915/gt/selftest_migrate.c
> > > @@ -55,8 +55,10 @@ static int copy(struct intel_migrate *migrate,
> > >
> > > sz = src->base.size;
> > > dst = i915_gem_object_create_internal(i915, sz);
> > > - if (IS_ERR(dst))
> > > + if (IS_ERR(dst)) {
> > > + err = PTR_ERR(dst);
> > > goto err_free_src;
> > > + }
> >
> > I think it was intentional to return '0' when
> > i915_gem_object_create_internal() failed, as we are not testing
> > object creation here.
> >
> > I don't really mind this patch, but, on the other hand, returning
> > an error value here might provide a biased information.
>
> Something we could consider is to make it more obvious that it's
> intentional. Smatch counts it as intentional if there is an "err = 0;"
> within a few lines of the goto.
>
> But let's just leave it. I've already marked this static checker
> warning as dealt with. If I see it again and maybe that will motivate
> me to add an err = 0; assignment. People imagine that kernel code must
> be 100% perfect with no static checker warnings etc but really it's
> almost the weekend and this is fine.

yes, I can accept an explicit "err = 0" with a comment on it. I
think it totally makes sense.

Do you want to do it or shall I take care of it?

Thanks,
Andi