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Date:   Fri, 29 Oct 2021 15:14:00 +0100
From:   Brian Starkey <brian.starkey@arm.com>
To:     George Kennedy <george.kennedy@oracle.com>
Cc:     Ville =?utf-8?B?U3lyasOkbMOk?= <ville.syrjala@linux.intel.com>,
        gregkh@linuxfoundation.org, maarten.lankhorst@linux.intel.com,
        mripard@kernel.org, tzimmermann@suse.de, airlied@linux.ie,
        daniel@ffwll.ch, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, ben.davis@arm.com,
        Liviu.Dudau@arm.com, Dan Carpenter <dan.carpenter@oracle.com>,
        nd@arm.com
Subject: Re: [PATCH] drm: check drm_format_info hsub and vsub to avoid divide
 by zero
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List-ID: <linux-kernel.vger.kernel.org>
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Hi,

On Fri, Oct 29, 2021 at 09:15:28AM -0400, George Kennedy wrote:
> 
> Asking if you have any input on how to deal with hsub and vsub = zero?

That's just a straight mistake on those formats - they should
be 1. My bad for not spotting it in review.

On the one hand, having formats in this table is a nice
machine-readable way to describe them. On the other, as drm_fourcc is
being used as the canonical repository for formats, including ones
not used in DRM, we can end up with situations like this.
(R10/R12 being another example of formats not used in DRM:
20211027233140.12268-1-laurent.pinchart@ideasonboard.com)

Thanks,
-Brian