linux-kernel - Re: [PATCH 1/2] drm_edid: Add a function to get EDID base block

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAD=FV=W+fRDOS01LKkeq-k12mj6jnFu5LOc9jAE3LA5w2ubo5g@mail.gmail.com>
Date: Tue, 27 Feb 2024 08:50:23 -0800
From: Doug Anderson <dianders@...omium.org>
To: Jani Nikula <jani.nikula@...ux.intel.com>
Cc: Hsin-Yi Wang <hsinyi@...omium.org>, Neil Armstrong <neil.armstrong@...aro.org>, 
	Jessica Zhang <quic_jesszhan@...cinc.com>, Sam Ravnborg <sam@...nborg.org>, 
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, Maxime Ripard <mripard@...nel.org>, 
	Thomas Zimmermann <tzimmermann@...e.de>, David Airlie <airlied@...il.com>, Daniel Vetter <daniel@...ll.ch>, 
	dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] drm_edid: Add a function to get EDID base block

Hi,

On Tue, Feb 27, 2024 at 1:09 AM Jani Nikula <jani.nikula@...ux.intel.com> wrote:
>
> On Fri, 23 Feb 2024, Hsin-Yi Wang <hsinyi@...omium.org> wrote:
> > It's found that some panels have variants that they share the same panel id
> > although their EDID and names are different. Besides panel id, now we need
> > the hash of entire EDID base block to distinguish these panel variants.
> >
> > Add drm_edid_get_base_block to returns the EDID base block, so caller can
> > further use it to get panel id and/or the hash.
>
> Please reconsider the whole approach here.
>
> Please let's not add single-use special case functions to read an EDID
> base block.
>
> Please consider reading the whole EDID, using the regular EDID reading
> functions, and use that instead.
>
> Most likely you'll only have 1-2 blocks anyway. And you might consider
> caching the EDID in struct panel_edp if reading the entire EDID is too
> slow. (And if it is, this is probably sensible even if the EDID only
> consists of one block.)

That makes a lot of sense! Not quite sure why I didn't just read the
whole EDID in the first place when trying to get the panel ID.

-Doug