linux-kernel - Re: [PATCH] drm: of: Properly try all possible cases for bridge/panel detection

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] [day] [month] [year] [list]

Message-ID: <YjSu4QSocJkvI1QQ@aptenodytes>
Date:   Fri, 18 Mar 2022 17:10:09 +0100
From:   Paul Kocialkowski <paul.kocialkowski@...tlin.com>
To:     Jagan Teki <jagan@...rulasolutions.com>
Cc:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        Linus Walleij <linus.walleij@...aro.org>
Subject: Re: [PATCH] drm: of: Properly try all possible cases for
 bridge/panel detection

Hi Jagan,

On Fri 18 Mar 22, 21:35, Jagan Teki wrote:
> Hi Paul,
> 
> On Wed, Mar 9, 2022 at 8:02 PM Paul Kocialkowski
> <paul.kocialkowski@...tlin.com> wrote:
> >
> > While bridge/panel detection was initially relying on the usual
> > port/ports-based of graph detection, it was recently changed to
> > perform the lookup on any child node that is not port/ports
> > instead when such a node is available, with no fallback on the
> > usual way.
> >
> > This results in breaking detection when a child node is present
> > but does not contain any panel or bridge node, even when the
> > usual port/ports-based of graph is there.
> 
> Can you add that pipeline example on the commit message, it gives more
> information on specific use cases why the existing code breaks.

Ah I just sent v2 before reading your message.

Well I think the description says it all: the problem shows as soon as there's
a child node to the node passed to drm_of_find_panel_or_bridge and it's really
independent from the of graph setup in the end.

I think Maxime put some examples on the original thread (v4 of your patch).

Paul

-- 
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)