<html>
<head>
<base href="https://bugs.freedesktop.org/">
</head>
<body><span class="vcard"><a class="email" href="mailto:martin.peres@free.fr" title="Martin Peres <martin.peres@free.fr>"> <span class="fn">Martin Peres</span></a>
</span> changed
<a class="bz_bug_link
bz_status_ASSIGNED "
title="ASSIGNED - [CI] igt@kms_rotation_crc@* - CRC mismatch"
href="https://bugs.freedesktop.org/show_bug.cgi?id=103925">bug 103925</a>
<br>
<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>What</th>
<th>Removed</th>
<th>Added</th>
</tr>
<tr>
<td style="text-align:right;">Priority</td>
<td>high
</td>
<td>medium
</td>
</tr>
<tr>
<td style="text-align:right;">i915 platform</td>
<td>BXT, CFL, CNL, KBL
</td>
<td>BYT
</td>
</tr></table>
<p>
<div>
<b><a class="bz_bug_link
bz_status_ASSIGNED "
title="ASSIGNED - [CI] igt@kms_rotation_crc@* - CRC mismatch"
href="https://bugs.freedesktop.org/show_bug.cgi?id=103925#c27">Comment # 27</a>
on <a class="bz_bug_link
bz_status_ASSIGNED "
title="ASSIGNED - [CI] igt@kms_rotation_crc@* - CRC mismatch"
href="https://bugs.freedesktop.org/show_bug.cgi?id=103925">bug 103925</a>
from <span class="vcard"><a class="email" href="mailto:martin.peres@free.fr" title="Martin Peres <martin.peres@free.fr>"> <span class="fn">Martin Peres</span></a>
</span></b>
<pre>The igt@kms_rotation_crc is verifying that the HW properly supports rotations.
A rotated FB is created using the CPU, displayed, then a CRC is collected.
Then, the non-rotated version of the same FB is created, displayed rotated
using the rotation KMS property, and the CRC is compared to the previous one.
If they do not match, then it means the HW implementation is differing from the
SW one.
We trust the SW implementation of the rotation, so this failure means that the
HW is behaving in an unexpected way.
The worst possible user impact is that rotated displays are corrupted on the
affected platforms (mostly BSW, BYT, GLK, SKL?, which seem to be the slowest
machines we have). On ICL, the reproduction rate is really low (2 failures in
1.5 months, once on icl-y, once on icl-u).
This is mostly affecting slow platforms, which are not usually used as desktop
PC which is were rotated displays may be seen the most. Tablet-like machines do
not use upstream. Also, BYT, BSW and GLK have been broken for years, without
users filing bugs for it. Because of this, let's lower the priority of this bug
to reflect the small portion of affected users in the worst case scenario (if
any).</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are the QA Contact for the bug.</li>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>