Re: [PATCH v2] x86, hotplug: fix llc shared map unreleased during cpu hotplug

Borislav Petkov
2014-07-22T09:44:30Z

On Tue, Jul 22, 2014 at 05:30:23PM +0800, Wanpeng Li wrote:
> On Tue, Jul 22, 2014 at 04:46:41AM -0400, Chen, Gong wrote:
> >On Tue, Jul 22, 2014 at 04:04:52PM +0800, Wanpeng Li wrote:
> >> Subject: [PATCH v2] x86, hotplug: fix llc shared map unreleased during cpu
> >> hotplug
> >
> >See this link:
> >https://lkml.org/lkml/2014/7/17/78
>
> Interesting, thanks for your pointing out.

Well, we might end up doing both.

Yasuaki's patch makes the core numbering stable which makes a lot of
sense in and of itself.

However, if some code somewhere relies implicitly on the fact that a set
bit in LLC mask means that core is online and goes and does stuff on it,
Wanpeng's reported splat will happen.

So probably we will have to have *stable* core numbers *and* clear the
LLC mask in order to be on the safe side of things.

Thanks.

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
--