Re: [PATCH v5 10/11] drm/xe/configfs: Only allow configurations for supported devices

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Tue, Jul 29, 2025 at 01:42:14PM +0200, Michal Wajdeczko wrote:
> Since we already lookup for the real PCI device before we allow
> to create its directory config, we might also check if the found
> device matches our driver PCI ID list. This will prevent creation
> of the directory configs for the unsupported devices.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
> ---
> v2: rebased
> ---
>  drivers/gpu/drm/xe/xe_configfs.c | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_configfs.c b/drivers/gpu/drm/xe/xe_configfs.c
> index 5f145ccdf535..766775772eef 100644
> --- a/drivers/gpu/drm/xe/xe_configfs.c
> +++ b/drivers/gpu/drm/xe/xe_configfs.c
> @@ -275,11 +275,22 @@ static const struct config_item_type xe_config_device_type = {
>  	.ct_owner	= THIS_MODULE,
>  };
>  
> +static const struct xe_device_desc *xe_match_desc(struct pci_dev *pdev)
> +{
> +	struct device_driver *driver = driver_find("xe", &pci_bus_type);
> +	struct pci_driver *drv = to_pci_driver(driver);
> +	const struct pci_device_id *ids = drv ? drv->id_table : NULL;
> +	const struct pci_device_id *found = pci_match_id(ids, pdev);
> +
> +	return found ? (const void *)found->driver_data : NULL;
> +}
> +
>  static struct config_group *xe_config_make_device_group(struct config_group *group,
>  							const char *name)
>  {
>  	unsigned int domain, bus, slot, function;
>  	struct xe_config_group_device *dev;
> +	const struct xe_device_desc *match;
>  	struct pci_dev *pdev;
>  	char canonical[16];
>  	int ret;
> @@ -297,8 +308,14 @@ static struct config_group *xe_config_make_device_group(struct config_group *gro
>  	pdev = pci_get_domain_bus_and_slot(domain, bus, PCI_DEVFN(slot, function));
>  	if (!pdev)
>  		return ERR_PTR(-ENODEV);
> +
> +	match = xe_match_desc(pdev);
> +
>  	pci_dev_put(pdev);
>  
> +	if (!match)
> +		return ERR_PTR(-ECANCELED);

why ECANCELED instead of ENODEV?

> +
>  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
>  	if (!dev)
>  		return ERR_PTR(-ENOMEM);
> -- 
> 2.47.1
>