• Bug#878170: xserver-xorg-video-radeon: Fails to match video to vsync

    From Michel =?UTF-8?Q?D=C3=A4nzer?=@21:1/5 to Anton Ivanov on Fri Oct 13 00:20:06 2017
    XPost: linux.debian.bugs.dist

    On 10/10/17 07:50 PM, Anton Ivanov wrote:
    Package: xserver-xorg-video-radeon
    Version: 1:7.8.0-1+b1
    Severity: important

    Dear Maintainer,

    Radeon (and amdgpu for that matter) in stretch no longer match frames
    to vsync correctly. This is observable with vdpau, opengl and plain
    xvideo.

    This used to work correctly in jessie so this is a recent regression.

    This is also observable in both full screen and windowed mode. The
    bottom ~5-10% of the picture updates on the wrong vsycn which is
    clearly visible especially in action sequences and animation.

    Tested with vlc, mplayer, xine and other software in a variety of
    output modes. I think I have eliminated other possible common factors
    leaving the video driver (and/or firmware) the most likely culprit.

    The only possibilities for reliably avoiding tearing in Xorg have always
    been:

    1. Using a compositing manager which uses OpenGL for rendering
    2. Running an application in fullscreen, using page flipping (i.e. the
    application must use something like OpenGL / VDPAU / VA-API / ... for
    rendering / presentation, but not something like XVideo or even pure
    X11)
    3. Enabling TearFree

    Note that 1.+2. are not sufficient when using rotation or other
    transforms via the RandR extension.


    Does your setup fall under any of these cases? If not, you may just have
    gotten lucky before.


    --
    Earthling Michel Dänzer | http://www.amd.com
    Libre software enthusiast | Mesa and X developer

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Anton Ivanov@21:1/5 to michel@daenzer.net on Fri Oct 13 00:20:03 2017
    XPost: linux.debian.bugs.dist

    It tears in full screen with and without compositing in xfce



    On 11 October 2017 09:40:59 BST, "Michel Dänzer" <michel@daenzer.net> wrote: >On 10/10/17 07:50 PM, Anton Ivanov wrote:
    Package: xserver-xorg-video-radeon
    Version: 1:7.8.0-1+b1
    Severity: important

    Dear Maintainer,

    Radeon (and amdgpu for that matter) in stretch no longer match frames
    to vsync correctly. This is observable with vdpau, opengl and plain
    xvideo.

    This used to work correctly in jessie so this is a recent regression.

    This is also observable in both full screen and windowed mode. The
    bottom ~5-10% of the picture updates on the wrong vsycn which is
    clearly visible especially in action sequences and animation.

    Tested with vlc, mplayer, xine and other software in a variety of
    output modes. I think I have eliminated other possible common factors
    leaving the video driver (and/or firmware) the most likely culprit.

    The only possibilities for reliably avoiding tearing in Xorg have
    always
    been:

    1. Using a compositing manager which uses OpenGL for rendering
    2. Running an application in fullscreen, using page flipping (i.e. the
    application must use something like OpenGL / VDPAU / VA-API / ... for
    rendering / presentation, but not something like XVideo or even pure
    X11)
    3. Enabling TearFree

    Note that 1.+2. are not sufficient when using rotation or other
    transforms via the RandR extension.


    Does your setup fall under any of these cases? If not, you may just
    have
    gotten lucky before.


    --
    Earthling Michel Dänzer |
    http://www.amd.com
    Libre software enthusiast | Mesa and X
    developer

    --
    Sent from my Android device with K-9 Mail. Please excuse my brevity. <html><head></head><body>It tears in full screen with and without compositing in xfce<br>

    <br><br><div class="gmail_quote">On 11 October 2017 09:40:59 BST, &quot;Michel Dänzer&quot; &lt;michel@daenzer.net&gt; wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
    <pre class="k9mail">On 10/10/17 07:50 PM, Anton Ivanov wrote:<br /><blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"> Package: xserver-xorg-video-radeon<br /> Version: 1:7.8.0-1+b1<br />
    Severity: important<br /> <br /> Dear Maintainer,<br /> <br /> Radeon (and amdgpu for that matter) in stretch no longer match frames<br /> to vsync correctly. This is observable with vdpau, opengl and plain<br /> xvideo. <br /> <br /> This used to work
    correctly in jessie so this is a recent regression.<br /> <br /> This is also obser
  • From Michel =?UTF-8?Q?D=C3=A4nzer?=@21:1/5 to Anton Ivanov on Fri Oct 13 01:10:14 2017
    XPost: linux.debian.bugs.dist

    On 11/10/17 10:58 AM, Anton Ivanov wrote:
    It tears in full screen with and without compositing in xfce

    Tearing is expected while compositing is in effect, because xfwm4 4.12's compositor cannot avoid tearing.

    So the question is why there's tearing even without compositing. Can you provide the terminal output of e.g. mplayer when there is tearing in fullscreen?


    --
    Earthling Michel Dänzer | http://www.amd.com
    Libre software enthusiast | Mesa and X developer

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)