On Wed, Jun 25, 2025 at 01:39:35PM -0400, Rodrigo Vivi wrote:
> On Wed, Jun 25, 2025 at 10:21:58AM -0500, Dan Carpenter wrote:
> > There was an error pointer vs NULL bug in __igt_breadcrumbs_smoketest().
> > The __mock_request_alloc() function implements the
> > smoketest->request_alloc() function pointer. It was supposed to return
> > error pointers, but it propogates the NULL return from mock_request()
> > so in the event of a failure, it would lead to a NULL pointer
> > dereference.
> >
> > To fix this, change the mock_request() function to return error pointers
> > and update all the callers to expect that.
> >
> > Fixes: 52c0fdb25c7c ("drm/i915: Replace global breadcrumbs with per-context
> > interrupt tracking")
> > Signed-off-by: Dan Carpenter <dan.carpen...@linaro.org>
> > ---
> > V2: In v1 I just updated __mock_request_alloc() to return an error pointer
> > but in v2, I changed mock_request() to update an error pointer and
> > updated all the callers. It's a more extensive change, but hopefully
> > cleaner.
>
> Thank you
>
> Reviewed-by: Rodrigo Vivi <rodrigo.v...@intel.com>
and pushed to drm-intel-next
Thanks again
>
>
> >
> > drivers/gpu/drm/i915/selftests/i915_request.c | 20 +++++++++----------
> > drivers/gpu/drm/i915/selftests/mock_request.c | 2 +-
> > 2 files changed, 11 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c
> > b/drivers/gpu/drm/i915/selftests/i915_request.c
> > index 88870844b5bd..2fb7a9e7efec 100644
> > --- a/drivers/gpu/drm/i915/selftests/i915_request.c
> > +++ b/drivers/gpu/drm/i915/selftests/i915_request.c
> > @@ -73,8 +73,8 @@ static int igt_add_request(void *arg)
> > /* Basic preliminary test to create a request and let it loose! */
> >
> > request = mock_request(rcs0(i915)->kernel_context, HZ / 10);
> > - if (!request)
> > - return -ENOMEM;
> > + if (IS_ERR(request))
> > + return PTR_ERR(request);
> >
> > i915_request_add(request);
> >
> > @@ -91,8 +91,8 @@ static int igt_wait_request(void *arg)
> > /* Submit a request, then wait upon it */
> >
> > request = mock_request(rcs0(i915)->kernel_context, T);
> > - if (!request)
> > - return -ENOMEM;
> > + if (IS_ERR(request))
> > + return PTR_ERR(request);
> >
> > i915_request_get(request);
> >
> > @@ -160,8 +160,8 @@ static int igt_fence_wait(void *arg)
> > /* Submit a request, treat it as a fence and wait upon it */
> >
> > request = mock_request(rcs0(i915)->kernel_context, T);
> > - if (!request)
> > - return -ENOMEM;
> > + if (IS_ERR(request))
> > + return PTR_ERR(request);
> >
> > if (dma_fence_wait_timeout(&request->fence, false, T) != -ETIME) {
> > pr_err("fence wait success before submit (expected
> > timeout)!\n");
> > @@ -219,8 +219,8 @@ static int igt_request_rewind(void *arg)
> > GEM_BUG_ON(IS_ERR(ce));
> > request = mock_request(ce, 2 * HZ);
> > intel_context_put(ce);
> > - if (!request) {
> > - err = -ENOMEM;
> > + if (IS_ERR(request)) {
> > + err = PTR_ERR(request);
> > goto err_context_0;
> > }
> >
> > @@ -237,8 +237,8 @@ static int igt_request_rewind(void *arg)
> > GEM_BUG_ON(IS_ERR(ce));
> > vip = mock_request(ce, 0);
> > intel_context_put(ce);
> > - if (!vip) {
> > - err = -ENOMEM;
> > + if (IS_ERR(vip)) {
> > + err = PTR_ERR(vip);
> > goto err_context_1;
> > }
> >
> > diff --git a/drivers/gpu/drm/i915/selftests/mock_request.c
> > b/drivers/gpu/drm/i915/selftests/mock_request.c
> > index 09f747228dff..1b0cf073e964 100644
> > --- a/drivers/gpu/drm/i915/selftests/mock_request.c
> > +++ b/drivers/gpu/drm/i915/selftests/mock_request.c
> > @@ -35,7 +35,7 @@ mock_request(struct intel_context *ce, unsigned long
> > delay)
> > /* NB the i915->requests slab cache is enlarged to fit mock_request */
> > request = intel_context_create_request(ce);
> > if (IS_ERR(request))
> > - return NULL;
> > + return request;
> >
> > request->mock.delay = delay;
> > return request;
> > --
> > 2.47.2
> >
