Re: [PATCH] xen, apic: Setup our own APIC driver and validator for APIC IDs.

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Mar 02, 2015 at 05:25:55PM +0000, David Vrabel wrote:
> On 02/03/15 17:06, Konrad Rzeszutek Wilk wrote:
> > Subject: [PATCH] x86/xen: Provide a "Xen PV" APIC driver to support >255 VCPUs
> > 
> > Instead of mangling the default APIC driver, provide a Xen PV guest
> > specific one that explicitly provides appropriate methods.
> > 
> > This allows use to report that all APIC IDs are valid, allowing dom0
> > to boot with more than 255 VCPUs.
> > 
> > Since the probe order of APIC drivers is link dependent, we add in an
> > late probe function to change to the Xen PV if it hadn't been done
> > during bootup.
> 
> Applied to devel/for-linus-4.1, thanks.

Thank you.
> 
> I've only given the briefest of smoke-tests.  It would probably be a
> good idea to queue this branch for some testing early.

<nods>

I did the 'perf' test which does use the IPI in an PV guest and
in dom0 and it worked. And naturally bootup on an machine with an unholy
amount of CPUs (x2APIC) - and also smaller ones.

And then the smoke-test that Boris does as well (on a sister lab setup).

But it would be good to make sure this patch does not blow anything up.
> 
> David