[PATCH] drm/amdkfd: Fix type of reset_type parameter in hqd_destroy() callback

[Alex Deucher]

Applied.  Thanks!

Alex

On Mon, Oct 17, 2022 at 12:30 PM Nathan Chancellor <nathan at kernel.org> wrote:
>
> When booting a kernel compiled with CONFIG_CFI_CLANG on a machine with
> an RX 6700 XT, there is a CFI failure in kfd_destroy_mqd_cp():
>
>   [   12.894543] CFI failure at kfd_destroy_mqd_cp+0x2a/0x40 [amdgpu] (target: hqd_destroy_v10_3+0x0/0x260 [amdgpu]; expected type: 0x8594d794)
>
> Clang's kernel Control Flow Integrity (kCFI) makes sure that all
> indirect call targets have a type that exactly matches the function
> pointer prototype. In this case, hqd_destroy()'s third parameter,
> reset_type, should have a type of 'uint32_t' but every implementation of
> this callback has a third parameter type of 'enum kfd_preempt_type'.
>
> Update the function pointer prototype to match reality so that there is
> no more CFI violation.
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1738
> Signed-off-by: Nathan Chancellor <nathan at kernel.org>
> ---
>
> No Fixes tag, as I could not pin down exactly when this started. I
> suspect it is
>
> Fixes: 70539bd79500 ("drm/amd: Update MEC HQD loading code for KFD")
>
> but I did not want to add that without a second look. Feel free to add
> it during patch application if it makes sense.
>
>  drivers/gpu/drm/amd/include/kgd_kfd_interface.h | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/include/kgd_kfd_interface.h b/drivers/gpu/drm/amd/include/kgd_kfd_interface.h
> index e85364dff4e0..5cb3e8634739 100644
> --- a/drivers/gpu/drm/amd/include/kgd_kfd_interface.h
> +++ b/drivers/gpu/drm/amd/include/kgd_kfd_interface.h
> @@ -262,8 +262,9 @@ struct kfd2kgd_calls {
>                                 uint32_t queue_id);
>
>         int (*hqd_destroy)(struct amdgpu_device *adev, void *mqd,
> -                               uint32_t reset_type, unsigned int timeout,
> -                               uint32_t pipe_id, uint32_t queue_id);
> +                               enum kfd_preempt_type reset_type,
> +                               unsigned int timeout, uint32_t pipe_id,
> +                               uint32_t queue_id);
>
>         bool (*hqd_sdma_is_occupied)(struct amdgpu_device *adev, void *mqd);
>
>
> base-commit: 9abf2313adc1ca1b6180c508c25f22f9395cc780
> --
> 2.38.0
>