linux-kernel - Re: [RFC PATCH 04/10] drm/panel_helper: Introduce drm_panel

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]

Date:   Fri, 1 Sep 2023 16:44:37 -0700
From:   Doug Anderson <dianders@...omium.org>
To:     Maxime Ripard <mripard@...nel.org>
Cc:     dri-devel@...ts.freedesktop.org,
        Linus Walleij <linus.walleij@...aro.org>,
        Daniel Vetter <daniel@...ll.ch>,
        David Airlie <airlied@...il.com>,
        Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH 04/10] drm/panel_helper: Introduce drm_panel_helper

Hi,

On Fri, Sep 1, 2023 at 6:42 AM Doug Anderson <dianders@...omium.org> wrote:
>
> > > The above solves the problem with panels wanting to power sequence
> > > themselves at remove() time, but not at shutdown() time. Thus we'd
> > > still have a dependency on having all drivers use
> > > drm_atomic_helper_shutdown() so that work becomes a dependency.
> >
> > Does it? I think it can be done in parallel?
>
> I don't think it can be in parallel. While it makes sense for panels
> to call drm_panel_remove() at remove time, it doesn't make sense for
> them to call it at shutdown time. That means that the trick of having
> the panel get powered off in drm_panel_remove() won't help for
> shutdown. For shutdown, which IMO is the more important case, we need
> to wait until all drm drivers call drm_atomic_helper_shutdown()
> properly.

FWIW, it was a bit of a slog, but I've managed to put together a RFT
series. Good thing it's Friday and beer-o-clock. Please enjoy
reviewing.

Ugh. It's now two series because there are too many recipients. Email
is fun. OK, these should be at:

* https://lore.kernel.org/r/20230901234015.566018-1-dianders@chromium.org
- patches targeting drm-misc

* https://lore.kernel.org/r/20230901234202.566951-1-dianders@chromium.org
- patches targeting something that's not drm-misc

-Doug