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Subject: Re: [Xen-devel] [PATCH v2 08/11] xen/hvmlite: Extend APIC operations
 for HVMlite guests
To: David Vrabel <david.vrabel@citrix.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>, <konrad.wilk@oracle.com>
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From: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= <roger.pau@citrix.com>
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Date: Thu, 4 Feb 2016 13:14:44 +0100
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El 4/2/16 a les 11:04, David Vrabel ha escrit:
> On 01/02/16 15:38, Boris Ostrovsky wrote:
>> HVMlite guests need to be viewed as having APIC, otherwise smpboot code,
>> for example, will complain.
> 
> I think we should consider always giving HVMlite guests an emulated
> APIC.  I think this eliminates one of the biggest differences between
> HVMlite and native/KVM guests and will reduce the risk of future
> breakage in this area.

Right, I'm not opposed to that, but I think we should keep the hypercall
interface in order to bring up vCPUs. IMHO it's useful for unikernels
for example (do those support SMP?), and in general allows for
easier/faster CPU-bringup as compared to bare metal.

Then if we indeed decide to provide and emulated lapic, should we also
at least provide the ACPI MADT table in order to enumerate them?

Roger.