Re: [PATCH v2] drm/xe: Keep walking on SVM eviction failure

["Ghimiray, Himal Prasad" <himal.prasad.ghimiray@intel.com>]

On 18-09-2026 02:01, Matthew Brost wrote:
> The desired behavior for SVM eviction failures, which can occur due to
> various uncontrollable races, is for TTM to continue walking the LRU
> list and look for another eviction candidate. This is expressed by
> returning -ENOSPC from the ->move() callback.
> 
> Adjust the SVM eviction failure path because of races in ->move() to
> return -ENOSPC so that TTM continues searching for another buffer to
> evict.
> 
> Fixes: 3ca608dc7561 ("drm/xe: Basic SVM BO eviction")
> Cc: stable@vger.kernel.org
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> 
> ---
> v2:
>   - Only convert -EBUSY (races) to -ENOSPC
> ---
>   drivers/gpu/drm/xe/xe_bo.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
> index 9f3f0cb95afa..f2ab9bf43a86 100644
> --- a/drivers/gpu/drm/xe/xe_bo.c
> +++ b/drivers/gpu/drm/xe/xe_bo.c
> @@ -1044,6 +1044,13 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict,
>   		} else {
>   			drm_dbg(&xe->drm, "Evict system allocator BO failed=%pe\n",
>   				ERR_PTR(ret));
> +			/*
> +			 * The semantic we want upon SVM eviction failure
> +			 * because of racing access is keep walking for
> +			 * eviction, which is -ENOSPC.
> +			 */
> +			if (ret == -EBUSY)
> +				ret = -ENOSPC;

LGTM
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>

>   		}
>   
>   		goto out;