Re: [PATCH V19 11/15] drm/xe/ras: Cache disable_vram_page_offline policy at init

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Inconsistent default value for disable_vram_page_offline when configfs is disabled.
--

commit fc4ea47b91e45c757aade7da6b3575d972f0bc5f
Author: Tejas Upadhyay <tejas.upadhyay@intel.com>

drm/xe/ras: Cache disable_vram_page_offline policy at init

This commit caches the configfs attribute disable_vram_page_offline in
the xe_drm_ras structure at initialization. This avoids repeated configfs
lookups during page faults.

> diff --git a/drivers/gpu/drm/xe/xe_ras.c b/drivers/gpu/drm/xe/xe_ras.c
> index d25d25f775310..f11a743990044 100644
> --- a/drivers/gpu/drm/xe/xe_ras.c
> +++ b/drivers/gpu/drm/xe/xe_ras.c
[ ... ]
> @@ -804,6 +805,14 @@ void xe_ras_init(struct xe_device *xe)
>  {
>  	int ret;
>  
> +	/*
> +	 * TODO: Replace platform check with xe->info.has_disable_vram_page_offline
> +	 * once the feature flag is plumbed through device info.
> +	 */
> +	if (xe->info.platform == XE_CRESCENTISLAND)
> +		xe->ras.disable_vram_page_offline =
> +			xe_configfs_get_disable_vram_page_offline(to_pci_dev(xe->drm.dev));

[Severity: Medium]
Will this silently disable VRAM page offlining when configfs is disabled in
the kernel configuration?

When the kernel is built without configfs,
xe_configfs_get_disable_vram_page_offline() is provided by a stub in
drivers/gpu/drm/xe/xe_configfs.h that returns true.

The intended default behavior when configfs is enabled but the attribute is
not set appears to be false (allowing offlining), as defined by
device_defaults in drivers/gpu/drm/xe/xe_configfs.c. By calling the stub and
caching its return value here, kernels built without configfs will silently
have this hardware reliability feature disabled by default.

Should the stub in drivers/gpu/drm/xe/xe_configfs.h be updated to return
false to match the expected default behavior?

> +
>  	xe_drm_ras_init(xe);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260831064942.315720-17-tejas.upadhyay@intel.com?part=11