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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Reoccuring CPU pipe [A|B] FIFO underrun followed by corrupt external monitor"
href="https://bugs.freedesktop.org/show_bug.cgi?id=103029">103029</a>
</td>
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<th>Summary</th>
<td>Reoccuring CPU pipe [A|B] FIFO underrun followed by corrupt external monitor
</td>
</tr>
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<th>Product</th>
<td>DRI
</td>
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<th>Version</th>
<td>unspecified
</td>
</tr>
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<th>Hardware</th>
<td>x86-64 (AMD64)
</td>
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<th>OS</th>
<td>Linux (All)
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
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<th>Severity</th>
<td>normal
</td>
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<th>Priority</th>
<td>medium
</td>
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<th>Component</th>
<td>DRM/Intel
</td>
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<th>Assignee</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
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<th>Reporter</th>
<td>martin.weinberg@comcast.net
</td>
</tr>
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<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=134548" name="attach_134548" title="Output of lspci">attachment 134548</a> <a href="attachment.cgi?id=134548&action=edit" title="Output of lspci">[details]</a></span>
Output of lspci
Since Kernel 4.13, I've been experiencing problems with my Lenovo T440s while
on the Ultradock using HDMI. No problems on earlier kernel. This has occured
on 4.13.0 through 4.13.3 (*current*).
A mostly successful work around is to suspend and resume off the dock.
T440s is Haswell; output of lspci attached. I'm using Ubuntu 17.04, uname -a
is:
Linux magpie 4.13.3-041303-generic #201709200606 SMP Wed Sep 20 10:12:46 UTC
2017 x86_64 x86_64 x86_64 GNU/Linux
Specifically, the log contains entries like: *ERROR* fifo underrun on pipe B
Some fraction of the time, but not every time, this occurs, the external screen
becomes corrupted. It acts as if it's lost sync.
There are no additional kernel messages. To help, I rebooted with
drm.debug=0xe to capture an "event". I'm attaching part of the log with drm
messages below.</pre>
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