Re: [PATCH] Revert "drm/i915: fix vblank wait test condition"

Sitsofe Wheeler
2010-09-05T09:38:08Z

On Sun, Sep 05, 2010 at 10:58:45AM +0300, Pekka Enberg wrote:
>
> I haven't heard of this problem. Is it reported on LKML? Is it a
> regression from 2.6.35?

Yes I did report it on the LKML (the initial report is
http://lkml.org/lkml/2010/8/23/432 ) but I've being trying to track
other reports mentioning similar symptoms too (e.g. I mentioned the
previous link to you in http://lkml.org/lkml/2010/8/29/52 ) but it seems
like they might different. The Intel guys spent a good while doing
investigations and having me try patches which is what led to a half fix
( http://marc.info/?l=linux-kernel&m=128267471015593&w=2 ) but there are
still situations which show problems (e.g. after suspend to ram). I've
also created a bug on the xorg bugzilla (
http://bugs.freedesktop.org/show_bug.cgi?id=29857 ) which has more
debugging information. The problem is there are so many symptoms but
worse, the triggers are weird/marginal so it's hard to tell if it has
been fixed.

Yes it is a regression from 2.6.35 see
http://lkml.org/lkml/2010/8/24/132 where I bisected it down to commit
9d0498a2bf7455159b317f19531a3e5db2ecc9c4 .

--
Sitsofe | http://sucs.org/~sits/