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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 - [GLK] Fifo underrun when changing resolution"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=100302">100302</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>[GLK] Fifo underrun when changing resolution
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>DRI
          </td>
        </tr>

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

        <tr>
          <th>Hardware</th>
          <td>x86-64 (AMD64)
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux (All)
          </td>
        </tr>

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

        <tr>
          <th>Severity</th>
          <td>critical
          </td>
        </tr>

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

        <tr>
          <th>Component</th>
          <td>DRM/Intel
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>christophe.prigent@intel.com
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=130351" name="attach_130351" title="kern.log">attachment 130351</a> <a href="attachment.cgi?id=130351&action=edit" title="kern.log">[details]</a></span>
kern.log

System Environment
=======
Ubuntu 16.10
libdrm-2.4.75-7-gf6499b1 from <a href="http://cgit.freedesktop.org/mesa/drm">http://cgit.freedesktop.org/mesa/drm</a>
cairo 1.15.4-6-g5854dd9 from <a href="http://cgit.freedesktop.org/cairo">http://cgit.freedesktop.org/cairo</a>
Kernel: 4.10.0-15ccc64 branch drm-tip from <a href="https://cgit.freedesktop.org/drm-tip">https://cgit.freedesktop.org/drm-tip</a>
commit 15ccc648be8c8717d0e7b7d6ac6038394c15f898
Author: Ander Conselvan de Oliveira <<a href="mailto:ander.conselvan.de.oliveira@intel.com">ander.conselvan.de.oliveira@intel.com</a>>
Date:   Mon Feb 27 09:13:30 2017 +0200
drm-tip: 2017y-02m-27d-07h-11m-41s UTC integration manifest

Regression
=======
Tested for the first time

Bug detailed description
=======
This problem only affect eDP so far, but is sending FIFO under run in dmesg
after changing resolutions and having other programs running in the background

Reproduce Steps
==============
Enter in UI with your credentials
Open Libreoffice
Open glxgears
Open a terminal, change resolution
Xrandr --output eDP-1 --mode 1024x768
xrandr --output eDP-1 --mode 640x480
xrandr --output eDP-1 --mode 1920x1080


Expected Result
=============
dmesg should be clean of FIFO underun caused by kernel

Actual Result
===========
[  399.346861] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU
pipe A FIFO underrun
[  399.346967] [drm:intel_fbc_underrun_work_fn [i915]] Disabling FBC due to
FIFO  underrun.</pre>
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