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      <base href="https://bugs.freedesktop.org/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Massive graphical corruption on wide multihead display"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=85910">85910</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Massive graphical corruption on wide multihead display
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>xorg
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Other
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Driver/intel
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>chris@chris-wilson.co.uk
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>a.nielsen@shikadi.net
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Three monitors, set up as three screens with Xinerama enabled, left to right:

 - 2560x1600 normal rotation
 - 1600x1200 left rotation
 - 1600x1200 left rotation

If one of the 1600x1200 screens is rotated back to normal orientation,
everything continues to work fine.  But if *both* are rotated back to normal,
everything goes haywire.

When typing into a window parts of the screen will alternate between normal and
black, sometimes the whole screen will go black except for the last few letters
typed in a terminal, using a menu can make all three monitors flash between
grey and black over the whole screen, etc.  The mouse cursor is the only thing
that behaves normally the whole time.

Putting one of the screens back to 'left' rotation immediately makes everything
return to normal and all graphical corruption disappear.

This bug happens 100% of the time, and it doesn't matter whether the
arrangement is handled via xorg.conf or via xrandr, both methods are able to
produce (and then fix) the corruption by rotating the various screens.

It does not appear to be an issue with the overall X desktop size, because the
problem still happens if the origin of the screens is moved to overlap another
screen, reducing the size of the full X display.  When there is corruption, it
affects all three displays (it is not limited to the ones being rotated.)

Here is a sample config:

Section "Device"
    Identifier "d_intel"
    Driver "intel"

    Option "monitor-DP1"   "m_dell_3008wfp"
    Option "monitor-HDMI1" "m_dell_2001fp"
    Option "monitor-HDMI3" "m_dell_2007fp"
    Option "monitor-VGA1"  "none"
EndSection

Section "Monitor"
    Identifier "m_dell_3008wfp"

    Option "PreferredMode" "2560x1600"
    Option "Enable" "true"
    Option "Rotate" "normal"
    Option "Primary" "true"
EndSection

Section "Monitor"
    Identifier "m_dell_2001fp"

    Option "PreferredMode" "1600x1200"
    Option "Enable" "true"
#    Option "Rotate" "left"  # Corruption if both rotations are off
    Option "RightOf" "m_dell_3008wfp"
EndSection

Section "Monitor"
    Identifier "m_dell_2007fp"

    Option "PreferredMode" "1600x1200"
    Option "Enable" "true"
#    Option "Rotate" "left"  # Corruption if both rotations are off
#    Option "RightOf" "m_dell_2001fp"
    Option "Position" "2560 0"
EndSection

Section "Screen"
    Identifier "s_intel_1"
    Device "d_intel"
    Monitor "m_dell_3008wfp"
EndSection

Section "Screen"
    Identifier "s_intel_2"
    Device "d_intel"
    Monitor "m_dell_2001fp"
EndSection

Section "Screen"
    Identifier "s_intel_3"
    Device "d_intel"
    Monitor "m_dell_2007fp"
EndSection

Section "ServerLayout"
    Identifier   "l_intel"

    Screen "s_intel_1"
    Screen "s_intel_2"
    Screen "s_intel_3"
EndSection</pre>
        </div>
      </p>
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