<html>
    <head>
      <base href="https://bugs.freedesktop.org/" />
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - sna: (Haswell) X-server freezes when enabling DP at docking station"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=71267">71267</a>
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>chris@chris-wilson.co.uk
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>sna: (Haswell) X-server freezes when enabling DP at docking station
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>consume.noise@gmail.com
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Other
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Driver/intel
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>xorg
          </td>
        </tr></table>
      <p>
        <div>
        <pre>HW: Lenovo T440s with a Thinkpad Ultra Dock and a Dell U2410

The T440s was at the docking station when powering on.

If I start the X-server, plugin the Monitor to a DP connector at the docking
station and call `xrandr --output DP2 --preferred` the X-server freezes.
(Doesn't happen without the docking station at the mDP connector directly at
the notebook.)

By freeze I mean:
- no cursor movement
- no VT switching

Though the maschine is reachable via ssh:
- X-server ignores `kill -9`

After 2 minutes the following kernel message shows up:
[  480.195776] INFO: task kworker/0:1:34 blocked for more than 120 seconds.    
[  480.195779] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
[  480.195781] kworker/0:1     D 0000000000000246     0    34      2 0x00000000
[  480.195803] Workqueue: events ironlake_panel_vdd_work [i915]     
[  480.195805]  ffff880118cebd50 0000000000000046 0000000000014500
ffff880118cebfd8
[  480.195809]  ffff880118cebfd8 0000000000014500 ffff880119218870
ffff88011f214570
[  480.195812]  0000000000000001 ffff880118cebcd8 ffffffff8109a884
ffff88011f2d4500
[  480.195816] Call Trace:     
[  480.195822]  [<ffffffff8109a884>] ? dequeue_entity+0x144/0x4d0     
[  480.195825]  [<ffffffff81099815>] ? set_next_entity+0x95/0xb0     
[  480.195829]  [<ffffffff810135a8>] ? __switch_to+0x118/0x4e0     
[  480.195833]  [<ffffffff814e1029>] schedule+0x29/0x70     
[  480.195835]  [<ffffffff814e1463>] schedule_preempt_disabled+0x23/0x30       
[  480.195839]  [<ffffffff814df9d8>] __mutex_lock_slowpath+0x168/0x3b0         
[  480.195843]  [<ffffffff814dfc32>] mutex_lock+0x12/0x30     
[  480.195852]  [<ffffffffa060a8b5>] ironlake_panel_vdd_work+0x25/0x40 [i915]  
[  480.195855]  [<ffffffff8107c6e7>] process_one_work+0x167/0x450     
[  480.195858]  [<ffffffff8107d0f1>] worker_thread+0x121/0x3a0     
[  480.195861]  [<ffffffff8107cfd0>] ? manage_workers.isra.23+0x2b0/0x2b0      
[  480.195865]  [<ffffffff81083960>] kthread+0xc0/0xd0     
[  480.195868]  [<ffffffff810838a0>] ? kthread_create_on_node+0x120/0x120      
[  480.195871]  [<ffffffff814ea52c>] ret_from_fork+0x7c/0xb0     
[  480.195875]  [<ffffffff810838a0>] ? kthread_create_on_node+0x120/0x120

The bug occured with
  o kernel 3.10.12
  o xorg 1.14.3
  o xf86-video-intel 2.11.15

For this test and the following logs it has been reproduced with
  o kernel 3.11.6
  o xorg 1.14.4
  o xf86-video-intel (at git head - dc61705 sna: Use an inplace exchange for
large untiled BO).

A test with kernel 3.12 is in the queue.</pre>
        </div>
      </p>
      <hr>
      <span>You are receiving this mail because:</span>
      
      <ul>
          <li>You are the QA Contact for the bug.</li>
      </ul>
    </body>
</html>