[Mesa-dev] [Bug 36919] Yo Frankie: Crash in dst_register

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=36919

José Fonseca <jfonseca at vmware.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
                 CC|                            |brianp at vmware.com,
                   |                            |jfonseca at vmware.com

--- Comment #13 from José Fonseca <jfonseca at vmware.com> 2011-05-11 06:25:10 PDT ---
I've managed to get a gltrace that captures the assertion failure by recording
the app with AMD's fglrx driver:

  http://people.freedesktop.org/~jrfonseca/traces/yofrankie-1.1b-fglrx.trace

And I've run an automated git bisect with it:

  git bisect start 2812b60a84a2992516db28b37b305c2a7eb5f424
5d7c27f5ec2f30c264dc2d53c4980970b3a13ee5
  git bisect run /path/to/glretrace-bisect.py --build 'scons -j4 libgl-xlib' --
-b -db /srv/shared/automation/traces/yofrankie-1.1b-fglrx.trace

(I'll commit the glretrace-bisect.py script after cleanup it up)
and got

3aa21f93dc1329c6f956277f2746c2a0bdae5446 is the first bad commit
commit 3aa21f93dc1329c6f956277f2746c2a0bdae5446
Author: Ian Romanick <ian.d.romanick at intel.com>
Date:   Fri Apr 15 18:38:54 2011 -0700

    mesa: Fix bugs in ff fragment shader fog handling

    This patch fixes two bugs related to fog in the fixed-function
    fragment shader generation code.

    Fog was only lowered to instructions if MRTs were used.  The fragment
    shader assembler always lowers "fog option" code to instructions, and
    many drivers (e.g., r300) expect this.

    When fog lowering did happen, it was after the instruction count was
    checked against implementation limits.  Since fog lowering may add up
    to 5 instructions, a program that was below the limits before lowering
    may exceed the limits after lowering.

    NOTE: This is a candidate for the stable branches.

    Reviewed-by: Eric Anholt <eric at anholt.net>
    Acked-by: Corbin Simpson <MostAwesomeDude at gmail.com>
    Acked-by: Alex Deucher <alexdeucher at gmail.com>

It's a simple change, and finding the fix was trivial:

commit 7a271151a5d6990c8325008f19ab621d730d06c4
Author: José Fonseca <jfonseca at vmware.com>
Date:   Wed May 11 14:01:17 2011 +0100

    mesa: Don't append fog code for programs that don't output color.

    Fixes fdo 36919.

    NOTE: This is a candidate for the stable branches.

    It should be cherry-picked to the sames branches that
    3aa21f93dc1329c6f956277f2746c2a0bdae5446 was.

-- 
Configure bugmail: https://bugs.freedesktop.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.