Re: [PATCH v2 1/2] drm: Add a drm_drv_enabled() to check if drivers should be enabled

From: Sam Ravnborg <sam@ravnborg.org>
To: Javier Martinez Canillas <javierm@redhat.com>
Cc: "David Airlie" <airlied@linux.ie>,
	"Daniel Vetter" <daniel.vetter@ffwll.ch>,
	dri-devel@lists.freedesktop.org,
	"Gurchetan Singh" <gurchetansingh@chromium.org>,
	"Dave Airlie" <airlied@redhat.com>,
	amd-gfx@lists.freedesktop.org,
	"VMware Graphics" <linux-graphics-maintainer@vmware.com>,
	"Peter Robinson" <pbrobinson@gmail.com>,
	nouveau@lists.freedesktop.org, spice-devel@lists.freedesktop.org,
	"Michel Dänzer" <michel@daenzer.net>,
	"Ben Skeggs" <bskeggs@redhat.com>,
	intel-gfx@lists.freedesktop.org,
	"Jani Nikula" <jani.nikula@linux.intel.com>,
	"Hans de Goede" <hdegoede@redhat.com>,
	"Rodrigo Vivi" <rodrigo.vivi@intel.com>,
	virtualization@lists.linux-foundation.org,
	"Pekka Paalanen" <pekka.paalanen@collabora.com>,
	"Pan, Xinhui" <Xinhui.Pan@amd.com>,
	linux-kernel@vger.kernel.org,
	"Thomas Zimmermann" <tzimmermann@suse.de>,
	"Alex Deucher" <alexander.deucher@amd.com>,
	"Christian König" <christian.koenig@amd.com>
Subject: Re: [PATCH v2 1/2] drm: Add a drm_drv_enabled() to check if drivers should be enabled
Date: Thu, 4 Nov 2021 20:28:54 +0100	[thread overview]
Message-ID: <YYQ0doL/F3ULjXyr@ravnborg.org> (raw)
In-Reply-To: <eddff405-18f5-31cf-9981-27343384e12c@redhat.com>

Hi Javier,

> 
> >>>  
> >>> -	if (vgacon_text_force() && i915_modparams.modeset == -1)
> >>> +	ret = drm_drv_enabled(&driver);
> >>
> >> You pass the local driver variable here - which looks wrong as this is
> >> not the same as the driver variable declared in another file.
> >
> 
> Yes, Jani mentioned it already. I got confused and thought that the driver
> variable was also defined in the same compilation unit...
> 
> Maybe I could squash the following change?
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index b18a250e5d2e..b8f399b76363 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -89,7 +89,7 @@
>  #include "intel_region_ttm.h"
>  #include "vlv_suspend.h"
>  
> -static const struct drm_driver driver;
> +const struct drm_driver driver;
No, variables with such a generic name will clash.

Just add a
const drm_driver * i915_drm_driver(void)
{
	return &driver;
}

And then use this function to access the drm_driver variable.

	Sam
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization