<html>
    <head>
      <base href="https://bugs.freedesktop.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - WARNING: CPU: 11 PID: 1137 at drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:88 dm_dp_aux_transfer+0xa5/0xc0 [amdgpu]"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=107456">107456</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>WARNING: CPU: 11 PID: 1137 at drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:88 dm_dp_aux_transfer+0xa5/0xc0 [amdgpu]
          </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>normal
          </td>
        </tr>

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

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

        <tr>
          <th>Assignee</th>
          <td>dri-devel@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>marc@dragonfly.plus.com
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=140936" name="attach_140936" title="dmesg output">attachment 140936</a> <a href="attachment.cgi?id=140936&action=edit" title="dmesg output">[details]</a></span>
dmesg output

I see the following warning during boot with Linux kernel 4.18.0-rc6 & 4.17.10:

root@deepthought:~# dmesg | grep WARN
[    9.346100] WARNING: CPU: 11 PID: 1137 at
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:88
dm_dp_aux_transfer+0xa5/0xc0 [amdgpu]
[    9.346162] WARNING: CPU: 14 PID: 1139 at
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:88
dm_dp_aux_transfer+0xa5/0xc0 [amdgpu]


Hardware is Ryzen 7 2700x, Sapphire Technology Radeon RX 480, IIyama ProLite
XB2380HS connected via DVI.

It looks like "dm_dp_aux_transfer" is used to setup DisplayPort, using "struct
drm_dp_aux_msg — DisplayPort AUX channel transaction". Now, with my hardware I
don't have any monitors connected via DisplayPort. Is that relevant?

I patched in a "printk("msg->size = %d\n", msg->size);" and it displays the
result twice, which is curious.

# dmesg | grep -i "msg->size"
[    9.469511] msg->size = -5
[    9.469803] msg->size = -5

Anyway, full "dmesg" attached.</pre>
        </div>
      </p>


      <hr>
      <span>You are receiving this mail because:</span>

      <ul>
          <li>You are the assignee for the bug.</li>
      </ul>
    </body>
</html>