[Intel-gfx] [PATCH 2/3] drm/i915/gvt: Return -EIO if host enable_execlists not enabled when loading GVT-g

[Chris Wilson]

On Fri, May 26, 2017 at 11:04:18AM +0800, Chuanxiao Dong wrote:
> GVT-g relies on the enable_execlists parameter in i915. If this option
> is not enabled for GVT-g, should return -EIO to make i915 driver loading
> failed.
> 
> Suggested-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Signed-off-by: Chuanxiao Dong <chuanxiao.dong at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_gvt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_gvt.c b/drivers/gpu/drm/i915/intel_gvt.c
> index dde9c78..c90d476 100644
> --- a/drivers/gpu/drm/i915/intel_gvt.c
> +++ b/drivers/gpu/drm/i915/intel_gvt.c
> @@ -97,7 +97,7 @@ int intel_gvt_init(struct drm_i915_private *dev_priv)
>  
>  	if (!i915.enable_execlists) {
>  		DRM_INFO("GPU guest virtualisation [GVT-g] disabled due to disabled execlist submission [i915.enable_execlists module parameter]\n");
> -		goto bail;
> +		return -EIO;

Hmm, interesting debate as to whether or not you still want to set
i915.enable_gvt=0 to indicate gvt being lost. Since this will cause the
driver to fail to load, it should be now DRM_ERROR("and the error
message changed to reflect the fatal failure!") and having modprobe
report -EIO with i915.enable_gvt still to 1 seems like the best approach.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre