Nouveau - Feb 2014 - GeForce 6100 (NV4E) & nouveau regression in 3.12

2014-02-11 11:41 GMT+01:00 Ilia Mirkin <imirkin at
alum.mit.edu>:
> (b) bisect. you can (almost) definitely restrict the bisect to
> drivers/gpu/drm/nouveau. if you have additional computational power, i
> would recommend looking into distcc for speeding up the compiles. it
> may be interesting to also try 3.6.x since 3.7 received a pretty big
> rewrite. but a git bisect is a lot more direct in figuring these
> things out :)
>
> After I watched your video, it definitely brought back memories of
> another bug or perhaps email on this list a while back (definitely
> within the past year), but unfortunately I can't quite place it :(
I've finally bisected between 3.10 and 3.11:

78ae0ad403daf11cf63da86923d2b5dbeda3af8f is the first bad commit
commit 78ae0ad403daf11cf63da86923d2b5dbeda3af8f
Author: Ben Skeggs <bskeggs at redhat.com>
Date: Wed Aug 21 11:30:36 2013 +1000

    drm/nv04/disp: fix framebuffer pin refcounting

I've booted that commit and one commit older few times. Every time I
booted 78ae0ad I got corruption. Every time I booted 6ff8c76 (it's the
earlier commit), it was OK.

Ben: any idea why this commit caused regression for my hardware? From
the commit message I assume it was supposed to affect some ancient
nv04 hardware only. Did it accidentally touch my nv4e path code maybe?

-- 
Rafa?

On Sun, Feb 16, 2014 at 10:17 AM, Rafa? Mi?ecki <zajec5 at gmail.com>
wrote:
> 2014-02-11 11:41 GMT+01:00 Ilia Mirkin <imirkin at alum.mit.edu>:
>> (b) bisect. you can (almost) definitely restrict the bisect to
>> drivers/gpu/drm/nouveau. if you have additional computational power, i
>> would recommend looking into distcc for speeding up the compiles. it
>> may be interesting to also try 3.6.x since 3.7 received a pretty big
>> rewrite. but a git bisect is a lot more direct in figuring these
>> things out :)
>>
>> After I watched your video, it definitely brought back memories of
>> another bug or perhaps email on this list a while back (definitely
>> within the past year), but unfortunately I can't quite place it :(
>
> I've finally bisected between 3.10 and 3.11:
>
> 78ae0ad403daf11cf63da86923d2b5dbeda3af8f is the first bad commit
> commit 78ae0ad403daf11cf63da86923d2b5dbeda3af8f
> Author: Ben Skeggs <bskeggs at redhat.com>
> Date: Wed Aug 21 11:30:36 2013 +1000
>
>     drm/nv04/disp: fix framebuffer pin refcounting
>
> I've booted that commit and one commit older few times. Every time I
> booted 78ae0ad I got corruption. Every time I booted 6ff8c76 (it's the
> earlier commit), it was OK.
But I bet if you restart X, you get a backtrace, right?
>
> Ben: any idea why this commit caused regression for my hardware? From
> the commit message I assume it was supposed to affect some ancient
> nv04 hardware only. Did it accidentally touch my nv4e path code maybe?
All pre-nv50 hardware (including your nv4e) use this path.

  -ilia

2014-02-16 19:55 GMT+01:00 Ilia Mirkin <imirkin at
alum.mit.edu>:
> On Sun, Feb 16, 2014 at 10:17 AM, Rafa? Mi?ecki <zajec5 at gmail.com>
wrote:
>> 2014-02-11 11:41 GMT+01:00 Ilia Mirkin <imirkin at alum.mit.edu>:
>>> (b) bisect. you can (almost) definitely restrict the bisect to
>>> drivers/gpu/drm/nouveau. if you have additional computational
power, i
>>> would recommend looking into distcc for speeding up the compiles.
it
>>> may be interesting to also try 3.6.x since 3.7 received a pretty
big
>>> rewrite. but a git bisect is a lot more direct in figuring these
>>> things out :)
>>>
>>> After I watched your video, it definitely brought back memories of
>>> another bug or perhaps email on this list a while back (definitely
>>> within the past year), but unfortunately I can't quite place it
:(
>>
>> I've finally bisected between 3.10 and 3.11:
>>
>> 78ae0ad403daf11cf63da86923d2b5dbeda3af8f is the first bad commit
>> commit 78ae0ad403daf11cf63da86923d2b5dbeda3af8f
>> Author: Ben Skeggs <bskeggs at redhat.com>
>> Date: Wed Aug 21 11:30:36 2013 +1000
>>
>>     drm/nv04/disp: fix framebuffer pin refcounting
>>
>> I've booted that commit and one commit older few times. Every time
I
>> booted 78ae0ad I got corruption. Every time I booted 6ff8c76 (it's
the
>> earlier commit), it was OK.
>
> But I bet if you restart X, you get a backtrace, right?
That's right.

78ae0ad:
Corruptions

6ff8c76:
WARNING: at drivers/gpu/drm/nouveau/nouveau_bo.c:151
nouveau_bo_del_ttm+0x80/0x90 [nouveau]()
(after quiting X by "init 3")

-- 
Rafa?