Re: [PATCH v5 4/7] kvm, mem-hotplug: Reload L1' apic access page on migration in vcpu_enter_guest().

Gleb Natapov
2014-09-11T14:31:52Z

On Thu, Sep 11, 2014 at 04:24:04PM +0200, Paolo Bonzini wrote:
> Il 11/09/2014 16:21, Gleb Natapov ha scritto:
> > As far as I can tell the if that is needed there is:
> >
> > if (!is_guest_mode() || !(vmcs12->secondary_vm_exec_control & ECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES))
> > write(PIC_ACCESS_ADDR)
> >
> > In other words if L2 shares L1 apic access page then reload, otherwise do nothing.
>
> What if the page being swapped out is L1's APIC access page? We don't
> run prepare_vmcs12 in that case because it's an L2->L0->L2 entry, so we
> need to "do something".
We will do something on L2->L1 exit. We will call kvm_reload_apic_access_page().
That is what patch 5 of this series is doing.

--
Gleb.