Memory corruption starting in i915 code, in 3.2-rc5

[Ben Widawsky]

On 12/16/2011 11:22 AM, Keith Packard wrote:
> On Tue, 13 Dec 2011 19:26:50 +0100, Daniel Vetter <daniel at ffwll.ch> wrote:
>> On Tue, Dec 13, 2011 at 10:14:46AM -0800, Keith Packard wrote:
>>> On Tue, 13 Dec 2011 10:14:15 -0500, Alex Villací­s Lasso <a_villacis at palosanto.com> wrote:
>>>
>>>> By using a bootable USB stick, I could check the logs, which
>>>> showed many segfaults at /lib64/ld-2.14.90.so .
>>>
>>> Ouch!
>>>
>>> Please let me know if you find anything further; I'd like to get a
>>> revert sent upstream in the next day or so.
>>
>> I think the revert is trtd. But if you revert it, please also
>> revert/disable the ilk vt-d workaound or apply one of Ben's patches,
>> because that one _does_ blow up, too.
> 
> Only if VT-d is enabled though, and that patch is now old enough that
> reverting it may cause additional problems.
> 
> Ben's patches still appear to have problems -- they don't appear to
> resolve the infinite recursion issue for unknown reasons.
> 
> I'm going to revert the patch which causes the reported regression, then
> wait for Eric to finish up his request queue cleanups and revisit this
> problem after that.

If this is referring to Dave Airlie's comment that it blows up, I think
he took that back as a bad backport on his part (maybe he can confirm).

Aside from that, I never saw anyone report my patch as bad... or good.

Ben