linux-kernel - Re: [PATCH v2 8/9] drm/rockchip: gem: Don't alloc/free gem buf before drm dev registered

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Message-ID: <20170403074101.f3ykqpdphklwummz@phenom.ffwll.local>
Date:   Mon, 3 Apr 2017 09:41:01 +0200
From:   Daniel Vetter <daniel@...ll.ch>
To:     Jeffy Chen <jeffy.chen@...k-chips.com>
Cc:     linux-kernel@...r.kernel.org, briannorris@...omium.org,
        dianders@...omium.org, dri-devel@...ts.freedesktop.org,
        tfiga@...omium.org, linux-rockchip@...ts.infradead.org,
        zyw@...k-chips.com, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH v2 8/9] drm/rockchip: gem: Don't alloc/free gem buf
 before drm dev registered

On Sat, Apr 01, 2017 at 07:35:28PM +0800, Jeffy Chen wrote:
> Signed-off-by: Jeffy Chen <jeffy.chen@...k-chips.com>
> ---
> 
> Changes in v2: None

Wut? How is this even possible? If you haven't registered the driver yet,
there's no way for userspace to call allocation functions. Anything else
is a driver bug that should be handled by fixing the driver load sequence.
The only thing I can imagine is that you init the fbdev stuff too early,
in that case pls fix that. Not apply this duct-tape here.

Thanks, Daniel

> 
>  drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> index df9e570..2bf8024 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> @@ -184,6 +184,9 @@ static int rockchip_gem_alloc_buf(struct rockchip_gem_object *rk_obj,
>  	struct drm_device *drm = obj->dev;
>  	struct rockchip_drm_private *private = drm->dev_private;
>  
> +	if (!drm->registered)
> +		return -ENODEV;
> +
>  	if (private->domain)
>  		return rockchip_gem_alloc_iommu(rk_obj, alloc_kmap);
>  	else
> @@ -208,6 +211,11 @@ static void rockchip_gem_free_dma(struct rockchip_gem_object *rk_obj)
>  
>  static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj)
>  {
> +	struct drm_device *drm = rk_obj->base.dev;
> +
> +	if (!drm->registered)
> +		return;
> +
>  	if (rk_obj->pages)
>  		rockchip_gem_free_iommu(rk_obj);
>  	else
> -- 
> 2.1.4
> 
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

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