<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 - After commit f21a21983ef13a, the display is turned off"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=96675">96675</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>After commit f21a21983ef13a, the display is turned off
          </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>larry.finger@lwfinger.net
          </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=124717" name="attach_124717" title="Output of dmesg with drm.debug=3 taken AFTER the faulty commit">attachment 124717</a> <a href="attachment.cgi?id=124717&action=edit" title="Output of dmesg with drm.debug=3 taken AFTER the faulty commit">[details]</a></span>
Output of dmesg with drm.debug=3 taken AFTER the faulty commit

As soon as kernel 4.7-rcX is started, the display is blanked, and it is never
turned on again. This problem was bisected to commit
f21a21983ef13a031250c4c3f6018e29a549d0f1
("drm/i915: Splitting intel_dp_detect"). The adapter in question is the
integrated graphics controller on a Toshiba Tecra A50 laptop. The output of
"lspci -nnv" for that controller is as follows: 

00:02.0 VGA compatible controller [0300]: Intel Corporation 4th Gen Core
Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA
controller])
        Subsystem: Toshiba America Info Systems Device [1179:0002]
        Flags: bus master, fast devsel, latency 0, IRQ 27
        Memory at e0000000 (64-bit, non-prefetchable) [size=4M]
        Memory at d0000000 (64-bit, prefetchable) [size=256M]
        I/O ports at 4000 [size=64]
        Expansion ROM at <unassigned> [disabled]
        Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
        Capabilities: [d0] Power Management version 2
        Capabilities: [a4] PCI Advanced Features
        Kernel driver in use: i915
        Kernel modules: i915

Disabling i915 with a "nomodeset" on the kernel command line allows the system
to boot normally.</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>
          <li>You are the assignee for the bug.</li>
      </ul>
    </body>
</html>