linux-kernel - Re: [RFC PATCH v2 0/3] Add support modifiers for drivers whose planes only support linear layout

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:   Thu, 13 Jan 2022 13:44:18 +0000
From:   Daniel Stone <daniel@...ishbar.org>
To:     Tomohito Esaki <etom@...l.co.jp>
Cc:     dri-devel@...ts.freedesktop.org,
        Alex Deucher <alexander.deucher@....com>,
        Christian König <christian.koenig@....com>,
        "Pan, Xinhui" <Xinhui.Pan@....com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        Ben Skeggs <bskeggs@...hat.com>,
        Michel Dänzer <mdaenzer@...hat.com>,
        Simon Ser <contact@...rsion.fr>,
        Qingqing Zhuo <qingqing.zhuo@....com>,
        Bas Nieuwenhuizen <bas@...nieuwenhuizen.nl>,
        Mark Yacoub <markyacoub@...omium.org>,
        Sean Paul <seanpaul@...omium.org>,
        Evan Quan <evan.quan@....com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Petr Mladek <pmladek@...e.com>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>,
        Lee Jones <lee.jones@...aro.org>,
        Abhinav Kumar <abhinavk@...eaurora.org>,
        Dmitry Baryshkov <dmitry.baryshkov@...aro.org>,
        Rob Clark <robdclark@...omium.org>,
        amd-gfx@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        nouveau@...ts.freedesktop.org,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Damian Hobson-Garcia <dhobsong@...l.co.jp>,
        Takanari Hayama <taki@...l.co.jp>
Subject: Re: [RFC PATCH v2 0/3] Add support modifiers for drivers whose planes
 only support linear layout

Hi Esaki-san,

On Thu, 13 Jan 2022 at 09:44, Tomohito Esaki <etom@...l.co.jp> wrote:
> Some drivers whose planes only support linear layout fb do not support format
> modifiers.
> These drivers should support modifiers, however the DRM core should handle this
> rather than open-coding in every driver.
>
> In this patch series, these drivers expose format modifiers based on the
> following suggestion[1].

Thanks for the series, it looks like the right thing to do.

Can you please change the patch ordering though? At the moment there
will be a bisection break at patch #1, because the legacy drivers will
suddenly start gaining modifier support, before it is removed in patch
#2.

I think a better order would be:
  1: add fb_modifiers_not_supported flag to core and drivers
  2: add default modifiers (and set allow_fb_modifiers) if
fb_modifiers_not_supported flag is not set
  3: remove allow_fb_modifiers flag

Cheers,
Daniel