[Intel-gfx] [PATCH] drm/i915: Revert i915.semaphore=1 default from 47ae63e0

[Ivan Bulatovic]

On Tue, 24 May 2011 13:10:27 -0400
Andrew Lutomirski <luto at mit.edu> wrote:

> On Thu, May 19, 2011 at 4:50 PM, Andrew Lutomirski <luto at mit.edu>
> wrote:
> > On Thu, May 19, 2011 at 3:56 PM, Keith Packard <keithp at keithp.com>
> > wrote:
> >> On Fri, 13 May 2011 12:14:54 -0400, Andy Lutomirski <luto at MIT.EDU>
> >> wrote:
> >>
> >>> My Q67 / i7-2600 box has rev09 Sandy Bridge graphics.  It hangs
> >>> instantly when GNOME loads and it hangs so hard the reset button
> >>> doesn't work.  Setting i915.semaphore=0 fixes it.
> >>
> >> Can you describe precisely what hardware you have? The make and
> >> model of the motherboard and the exact model of CPU? I'd like to
> >> get this issue resolved for 2.6.40 and need to have a reliable way
> >> to reproduce the hang; replicating your hardware may be a good way
> >> of doing that.
> >
> 
> I'm getting hangs on my X220 Core i7 laptop as well with 2.6.39 and
> i915.semaphores=1.  They're not as reliable -- sometimes the system
> hangs on log in, sometimes after a few seconds, and sometimes it
> doesn't hang.
> 
> --Andy

I haven't had GPU hangs since this patch:

https://bugs.freedesktop.org/show_bug.cgi?id=33921#c23

Poll the FIFO for free entries before writing the register

Gigabyte GA-H67MA-UD2H-B3 + i5 2400 here.