Re: [Intel-gfx] [PATCH v3 06/28] drm/i915/gvt: Error out on an attempt to shadowing an unknown GTT entry type

Wang, Zhi A
2023-05-15T11:28:14Z

On 5/13/2023 8:35 AM, Sean Christopherson wrote:

Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>

> Bail from ppgtt_populate_shadow_entry() if an unexpected GTT entry type
> is encountered instead of subtly falling through to the common "direct
> shadow" path. Eliminating the default/error path's reliance on the common
> handling will allow hoisting intel_gvt_dma_map_guest_page() into the case
> statements so that the 2MiB case can try intel_gvt_dma_map_guest_page()
> and fallback to splitting the entry on failure.
>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---
> drivers/gpu/drm/i915/gvt/gtt.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
> index 2aed31b497c9..61e38acee2d5 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.c
> +++ b/drivers/gpu/drm/i915/gvt/gtt.c
> @@ -1306,6 +1306,7 @@ static int ppgtt_populate_shadow_entry(struct intel_vgpu *vgpu,
> return -EINVAL;
> default:
> GEM_BUG_ON(1);
> + return -EINVAL;
> }
>
> /* direct shadow */