[Bug 94122] New: [SKL] SKL freezes when using a sprite with two monitors connected

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=94122

            Bug ID: 94122
           Summary: [SKL] SKL freezes when using a sprite with two
                    monitors connected
           Product: DRI
           Version: unspecified
          Hardware: Other
                OS: All
            Status: NEW
          Severity: normal
          Priority: medium
         Component: DRM/Intel
          Assignee: intel-gfx-bugs at lists.freedesktop.org
          Reporter: przanoni at gmail.com
        QA Contact: intel-gfx-bugs at lists.freedesktop.org
                CC: intel-gfx-bugs at lists.freedesktop.org

How to reproduce the bug:
1. Get a SKL machine with eDP+HDMI connected
2. Boot it
3. Kill the display manager so fbcon shows up
4. sudo ./kms_frontbuffer_tracking --show-hidden --run-subtest nop-1p-rte
5. If the machine is not frozen (50% chance), wait a few seconds and then goto
step 4.

The machine freeze is a complete freeze. You can even see a red led lighting up
on the motherboard.

Notice that even though the subtest we're running only lights up a single pipe,
the bug only happens if I have eDP+HDMI connected.

Now, if you open kms_frontbuffer_tracking.c, go to function rte_subtest() and
then uncomment the call to set_sprite_for_test(), then you won't be able to
freeze the machine.

Notice that I've been experiencing different types of dual-monitor problems on
SKL even since. Previously, I couldn't even boot with eDP+HDMI because the
machine would freeze while loading the driver. Since some watermarks patches
solved this issue, I believe this bug may also have some relationship with
watermarks.

It is also worth mentioning that just booting my SKL machine with the two
monitors connected already gives me dmesg errors, such as WARN_ON(!wm_changed).

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20160212/e09dc75e/attachment.html>