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

[Andrew Lutomirski]

On Tue, Jun 7, 2011 at 3:12 AM, Eric Anholt <eric at anholt.net> wrote:
> On Thu, 19 May 2011 16:50:00 -0400, 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.
>>
>> Intel DQ67SW.  AMT is enabled but the port 5900 is closed (because I
>> can't figure out how to turn on the kvm).
>>
>> The system boots from UEFI (which is buggy, both because efifb doesn't
>> recognize my hardware, because asking the firmware for the boot menu
>> causes all efivars entries to be ignored, and because unless I set
>> reboot=k the system crashes on reboot).
>>
>> Userspace is F15 running compiz (*not* gnome-shell).
>>
>> BIOS is SWQ6710H.86A.0051.2011.0413.1154.
>>
>> CPU is:
>> processor       : 0
>> vendor_id       : GenuineIntel
>> cpu family      : 6
>> model           : 42
>> model name      : Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz
>> stepping        : 7
>
> I fear this bug is just "getting more asynchronous with the GPU means we
> trigger race conditions on the GPU more easily."  On that note, could
> you retest with Mesa as of this commit, since I'm told this is a GT1 CPU:
>
> commit ef59049c5242a1be7fa59a182d342191185dd62b
> Author: Eric Anholt <eric at anholt.net>
> Date:   Sun Jun 5 23:20:57 2011 -0700
>
>    i965: Fix flipped GT1 vs GT2 URB VS entry count limits.
>

Nope -- I still got the reset-button-not-working hang.

I'm pretty sure I installed mesa right -- I moved everything in
/usr/lib64/dri out of the way and put the files in mesa/lib/ in there.

--Andy