linux-kernel - Re: [PATCH v4 3/5] drm: add SimpleDRM driver

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]

Date:   Fri, 2 Sep 2016 08:11:11 +0200
From:   Daniel Vetter <daniel@...ll.ch>
To:     David Herrmann <dh.herrmann@...il.com>
Cc:     Noralf Trønnes <noralf@...nnes.org>,
        linux-kernel <linux-kernel@...r.kernel.org>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        devicetree <devicetree@...r.kernel.org>
Subject: Re: [PATCH v4 3/5] drm: add SimpleDRM driver

On Fri, Sep 2, 2016 at 1:48 AM, David Herrmann <dh.herrmann@...il.com> wrote:
> So either the drm_simple_kms_helpers are buggy, or the SimpleDRM use
> of it. On DPMS updates, I get:
>
> Sep 02 01:00:39 david-t2 kernel:
> [drm:drm_atomic_helper_commit_cleanup_done [drm_kms_helper]] *ERROR*
> [CRTC:25:crtc-0] flip_done timed out
> Sep 02 01:00:39 david-t2 kernel: ------------[ cut here ]------------
> Sep 02 01:00:39 david-t2 kernel: WARNING: CPU: 3 PID: 352 at
> drivers/gpu/drm/drm_atomic_helper.c:1549
> drm_atomic_helper_commit_hw_done+0xab/0xb0 [drm_kms_helper]
>
> The atomic-commit originates in:
> drm_atomic_helper_connector_dpms()
>
> Any idea what is missing there? I haven't looked much into the
> atomic-helpers, yet.

The bugfix for that is in latest drm-misc (or well, should be at
least). And you need to make sure to call drm_crtc_send_vblank_event
(if there's an event) from your update hook. That /should/ work, but I
didn't test it myself. flip_done not happening is when the
driver/helpers fail to submit the event for some reason or another.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch