Re: [PATCH v4 08/14] KVM: ARM: World-switch implementation

Will Deacon
2012-11-30T17:14:49Z

On Fri, Nov 30, 2012 at 04:47:40PM +0000, Christoffer Dall wrote:
> On Fri, Nov 30, 2012 at 10:15 AM, Will Deacon <will.deacon@arm.com> wrote:
> > At this point, VM1 is running and VM0:VCPU1 is running. VM0:VCPU0 is not
> > running because physical CPU0 is handling an interrupt. The problem is that
> > when VCPU0 *is* resumed, it will update the VMID of VM0 and could be
> > scheduled in parallel with VCPU1 but with a different VMID.
> >
> > How do you avoid this in the current code?
> >
> I don't. Nice catch. Please apply your interesting brain to the following fix:)

I'm far too sober to look at your patch right now, but I'll think about it
over the weekend [I can't break it at a quick glance] :)

In the meantime, can you think about whether the TLB operations need to run
on every CPU please?

Will