[PATCH] drm/xe/oa: Fix potential NPD when OA is not initialized

[Dixit, Ashutosh]

On Wed, 19 Jun 2024 10:54:27 -0700, Michal Wajdeczko wrote:
>
> If oa->xe can be NULL then we shall not use it as a valid pointer.

Hi Michal, thanks for catching this:

Reviewed-by: Ashutosh Dixit <ashutosh.dixit at intel.com>

> Fixes: cdf02fe1a94a ("drm/xe/oa/uapi: Add/remove OA config perf ops")
> Fixes: b6fd51c62119 ("drm/xe/oa/uapi: Define and parse OA stream properties")
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Ashutosh Dixit <ashutosh.dixit at intel.com>
> Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
> ---
>  drivers/gpu/drm/xe/xe_oa.c | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_oa.c b/drivers/gpu/drm/xe/xe_oa.c
> index 34206e0b6a08..2277af816a34 100644
> --- a/drivers/gpu/drm/xe/xe_oa.c
> +++ b/drivers/gpu/drm/xe/xe_oa.c
> @@ -1725,7 +1725,8 @@ static int xe_oa_user_extensions(struct xe_oa *oa, u64 extension, int ext_number
>   */
>  int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *file)
>  {
> -	struct xe_oa *oa = &to_xe_device(dev)->oa;
> +	struct xe_device *xe = to_xe_device(dev);
> +	struct xe_oa *oa = &xe->oa;
>	struct xe_file *xef = to_xe_file(file);
>	struct xe_oa_open_param param = {};
>	const struct xe_oa_format *f;
> @@ -1733,7 +1734,7 @@ int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *f
>	int ret;
>
>	if (!oa->xe) {
> -		drm_dbg(&oa->xe->drm, "xe oa interface not available for this system\n");
> +		drm_dbg(&xe->drm, "xe oa interface not available for this system\n");
>		return -ENODEV;
>	}
>
> @@ -2005,7 +2006,8 @@ static int create_dynamic_oa_sysfs_entry(struct xe_oa *oa,
>   */
>  int xe_oa_add_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *file)
>  {
> -	struct xe_oa *oa = &to_xe_device(dev)->oa;
> +	struct xe_device *xe = to_xe_device(dev);
> +	struct xe_oa *oa = &xe->oa;
>	struct drm_xe_oa_config param;
>	struct drm_xe_oa_config *arg = ¶m;
>	struct xe_oa_config *oa_config, *tmp;
> @@ -2013,7 +2015,7 @@ int xe_oa_add_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *fi
>	int err, id;
>
>	if (!oa->xe) {
> -		drm_dbg(&oa->xe->drm, "xe oa interface not available for this system\n");
> +		drm_dbg(&xe->drm, "xe oa interface not available for this system\n");
>		return -ENODEV;
>	}
>
> @@ -2106,13 +2108,14 @@ int xe_oa_add_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *fi
>   */
>  int xe_oa_remove_config_ioctl(struct drm_device *dev, u64 data, struct drm_file *file)
>  {
> -	struct xe_oa *oa = &to_xe_device(dev)->oa;
> +	struct xe_device *xe = to_xe_device(dev);
> +	struct xe_oa *oa = &xe->oa;
>	struct xe_oa_config *oa_config;
>	u64 arg, *ptr = u64_to_user_ptr(data);
>	int ret;
>
>	if (!oa->xe) {
> -		drm_dbg(&oa->xe->drm, "xe oa interface not available for this system\n");
> +		drm_dbg(&xe->drm, "xe oa interface not available for this system\n");
>		return -ENODEV;
>	}
>
> --
> 2.43.0
>