Re: [PATCH 1/2] drm/xe/vf: Don't support changing GuC reset policy

[Michal Wajdeczko <michal.wajdeczko@intel.com>]

On 03.04.2025 11:41, Lukasz Laguna wrote:
> VF can't change GuC reset policy. Ensure the driver does not attempt to
> do so by adding an assertion.

none of xe_guc_ads() functions are applicable for the VFs by definition,
since GuC ADS is purely a PF/native responsibility

why do we want to assert just one of these function?

it should either fail (due to use of the privileged H2G action) or crash
(due to use of previously uninitialized structures)

I'm not sure that we want to annotate/pollute all privileged parts of
the driver with !IS_SRIOV_VF asserts

> 
> Signed-off-by: Lukasz Laguna <lukasz.laguna@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_guc_ads.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_guc_ads.c b/drivers/gpu/drm/xe/xe_guc_ads.c
> index bee4e0cfe7b8..2ea07d28728e 100644
> --- a/drivers/gpu/drm/xe/xe_guc_ads.c
> +++ b/drivers/gpu/drm/xe/xe_guc_ads.c
> @@ -990,6 +990,8 @@ int xe_guc_ads_scheduler_policy_toggle_reset(struct xe_guc_ads *ads)
>  	struct xe_bo *bo;
>  	int ret = 0;
>  
> +	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
> +
>  	policies = kmalloc(sizeof(*policies), GFP_KERNEL);
>  	if (!policies)
>  		return -ENOMEM;