Re: [PATCH 3/4] drm/ttm: Don't leak a resource on eviction error

[Nirmoy Das]

On 6/22/2023 12:14 PM, Thomas Hellström wrote:
> On eviction errors other than -EMULTIHOP we were leaking a resource.
> Fix.
>
> Fixes: 403797925768 ("drm/ttm: Fix multihop assert on eviction.")
> Cc: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
> Cc: Christian König <christian.koenig@xxxxxxx>
> Cc: Christian Koenig <christian.koenig@xxxxxxx>
> Cc: Huang Rui <ray.huang@xxxxxxx>
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Cc: <stable@xxxxxxxxxxxxxxx> # v5.15+
> Signed-off-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>

Reviewed-by: Nirmoy Das <nirmoy.das@xxxxxxxxx>

> ---
>   drivers/gpu/drm/ttm/ttm_bo.c | 16 ++++++++--------
>   1 file changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index 615d30c4262d..89530f2a027f 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -462,14 +462,14 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo,
>   	ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
>   	if (ret == -EMULTIHOP) {
>   		ret = ttm_bo_bounce_temp_buffer(bo, &evict_mem, ctx, &hop);
> -		if (ret) {
> -			if (ret != -ERESTARTSYS && ret != -EINTR)
> -				pr_err("Buffer eviction failed\n");
> -			ttm_resource_free(bo, &evict_mem);
> -			goto out;
> -		}
> -		/* try and move to final place now. */
> -		goto bounce;
> +		if (!ret)
> +			/* try and move to final place now. */
> +			goto bounce;
> +	}
> +	if (ret) {
> +		ttm_resource_free(bo, &evict_mem);
> +		if (ret != -ERESTARTSYS && ret != -EINTR)
> +			pr_err("Buffer eviction failed\n");
>   	}
>   out:
>   	return ret;