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<base href="https://bugs.freedesktop.org/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Freeze during activation of external display on Lenovo X260"
href="https://bugs.freedesktop.org/show_bug.cgi?id=94930">94930</a>
</td>
</tr>
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<th>Summary</th>
<td>Freeze during activation of external display on Lenovo X260
</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>
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<th>OS</th>
<td>Linux (All)
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
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<th>Priority</th>
<td>medium
</td>
</tr>
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<th>Component</th>
<td>DRM/Intel
</td>
</tr>
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<th>Assignee</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>dennis.wassenberg@secunet.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=122921" name="attach_122921" title="dmesg drm.debug=1">attachment 122921</a> <a href="attachment.cgi?id=122921&action=edit" title="dmesg drm.debug=1">[details]</a></span>
dmesg drm.debug=1
Hi all,
I tried to connect an external display to a Lenovo X260. It doen't matter if it
is connected via HDMI or m-DP. Every time I activate the connected display
(e.g. Xubuntu - Settings->Display->Select External Display->Use this output)
the system will freeze completely. A reboot is possible by holding the power
button for 4 seconds only.
It is not possible to get a dmesg output which shows a kernel oops / panic
because the cpu seems to stop working completely. I will attach a default dmesg
output and a dmesg output with drm.debug=1. Even trying to create a crash dump
via pstore efi backend creates no crash dumps.
To make sure that this issue is not associated with
<a href="https://bugzilla.kernel.org/show_bug.cgi?id=110941">https://bugzilla.kernel.org/show_bug.cgi?id=110941</a> I added intel_pstate=no_hwp
to kernel command line.
This freeze will not occur with Ubuntu wily kernel <= 4.4.6. It starts freezing
with Ubuntu wily kernel >= 4.5. So maybe it looks like a regression? Using
Ubuntu xenial it freezes not dependent on the kernel version. I checked it with
default kernel of beta2 (Ubuntu-4.4.0-15) and the latest kernel
Ubuntu-4.4.0-18.34.
I dont't know if this is related to
<a class="bz_bug_link
bz_status_NEW "
title="NEW - Kernel 4.5.0 crashes when docking Lenovo T450s (with external monitor connected): GPF(drm_dp_payload_send_msg)"
href="show_bug.cgi?id=94534">https://bugs.freedesktop.org/show_bug.cgi?id=94534</a> but there a Haswell CPU is
involved (Skylake here).
I have also reported this bug on bugzilla.kernel.org
(<a href="https://bugzilla.kernel.org/show_bug.cgi?id=116201">https://bugzilla.kernel.org/show_bug.cgi?id=116201</a>), not sure where the best
place to report this is.
Best regards,
Dennis</pre>
</div>
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