[Nouveau] GeForce 6100 (NV4E) & nouveau regression in 3.12

[Rafał Miłecki]

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?

-- 
Rafał