[OE-core] Fix for the APIC hangs in qemux86-64

[Richard Purdie]

On Wed, 2017-12-13 at 08:38 -0500, Bruce Ashfield wrote:
> On 12/13/2017 07:34 AM, Richard Purdie wrote:
> > 
> > Hi Bruce,
> > 
> > https://bugzilla.yoctoproject.org/show_bug.cgi?id=12301
> > 
> > We've root caused the hangs we're seeing in qemux86-64 on our
> > autobuilder workers. We've identified a commit on 4.15-rc3 which
> > fixes
> > the issue but backporting it to the autobuilder's host kernels will
> > be
> > a pain.
> > 
> > As a workaround I'd like to enable x2apic on qemux86-64. Since that
> > works via MSRs it avoids the problem.
> > 
> > Would it be a big issue to set CONFIG_X86_X2APIC=y for qemux86-64?
> Nope. No big deal at all. I've used the same config i the past
> when doing work with rt-KVM, so I know it well.
> 
> I'll prep a commit, and send it along as part of a rebased set
> of kernel patches.

Thanks, much appreciated.

Did we get to the bottom of the 4.12 selftest failures?

We may also need to backport the defconfig change back to the older
releases so we don't get the hangs in those builds either...

Cheers,

Richard