[PATCH] drm/amdgpu: fixx NULL pointer deref in gmc_v9_0_get_vm_pte

[Alex Deucher]

On Wed, Dec 7, 2022 at 2:49 AM Christian König
<ckoenig.leichtzumerken at gmail.com> wrote:
>
> We not only need to make sure that we have a BO, but also that the BO
> has some backing store.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> index 50386eb2eec8..afc0cfed5065 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> @@ -1185,6 +1185,8 @@ static void gmc_v9_0_get_vm_pte(struct amdgpu_device *adev,
>                                 struct amdgpu_bo_va_mapping *mapping,
>                                 uint64_t *flags)
>  {
> +       struct amdgpu_bo *bo = mapping->bo_va->base.bo;
> +
>         *flags &= ~AMDGPU_PTE_EXECUTABLE;
>         *flags |= mapping->flags & AMDGPU_PTE_EXECUTABLE;
>
> @@ -1196,7 +1198,7 @@ static void gmc_v9_0_get_vm_pte(struct amdgpu_device *adev,
>                 *flags &= ~AMDGPU_PTE_VALID;
>         }
>
> -       if (mapping->bo_va->base.bo)
> +       if (bo && bo->resource)
>                 gmc_v9_0_get_coherence_flags(adev, mapping->bo_va->base.bo,
>                                              mapping, flags);
>  }
> --
> 2.34.1
>