SV: i915 update to Linux 3.8 ready!

[Anders Bolt-Evensen]

> -----Opprinnelig melding-----
> Fra: owner-freebsd-x11 at freebsd.org [mailto:owner-freebsd-
> x11 at freebsd.org] På vegne av Jean-Sébastien Pédron
> Sendt: fredag 11. mars 2016 22.08
> Til: freebsd-x11 at freebsd.org
> Emne: Re: i915 update to Linux 3.8 ready!
> 
> On 11/03/2016 21:23, Frederic Chardon wrote:
> > Hi!
> 
> Hi!
> 
> > I now have a very reproducible panic in Xorg on my 965GM (Dell
> > Latitude D630). No problem at the console with i915kms loaded.
> 
> How do you reproduce it?
> 
> > vm_fault: pager read error, pid 44151 (Xorg) Kernel page fault with
> > the following non-sleepable locks held:
> > exclusive rw vm object (vm object) r = 0 (0xfffff80205757528) locked @
> > /usr/src/sys/modules/drm2/i915kms/../../../dev/drm2/i915/i915_gem.c:16
> > 26
> > stack backtrace:
> > #0 0xffffffff80405490 at witness_debugger+0x70
> > #1 0xffffffff80406777 at witness_warn+0x3d7
> > #2 0xffffffff805eb137 at trap_pfault+0x57
> > #3 0xffffffff805ea7c4 at trap+0x284
> > #4 0xffffffff805cc857 at calltrap+0x8
> > #5 0xffffffff805a1428 at vm_fault+0x78
> > #6 0xffffffff805eb1f5 at trap_pfault+0x115
> > #7 0xffffffff805ea882 at trap+0x342
> > #8 0xffffffff805cc857 at calltrap+0x8
> 
> Could you please send the whole core.txt.$n?
> 
> --
> Jean-Sébastien Pédron

I am not 100 % sure it is the same issue as Frederic Chardon reported, but the problem I have is at least very similar to this one.
It seems to be a bit of a random problem. It does not occur every time, but when it does, it is "caused" by normal usage, e.g. working with a document in LibreOffice and browsing the web.
As a side note, I have been testing i915 for a few months now, and it's only after the merge to HEAD that this problem has occurred to me. I decided to switch back to HEAD once the new i915 driver was committed. 
Whole contents of core.txt.9 is available from here: https://www.dropbox.com/s/zbkwlqvp4hi3ukc/core.txt.9?dl=0 (I tried to include it as an attachment, but I got a message from the owner of the mailing list that said the message was too big, so I shared the file on Dropbox instead).

Like I said, it may or may not be the same problem as the one Frederic Chardon has, but if it is, I hope this will help identifying and/or solving the problem.

Anders