From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <levinsasha928@gmail.com>
Subject: Re: KVM_MAX_VCPUS
Date: Sat, 13 Oct 2012 22:32:13 -0400
Message-ID: <507A242D.9070708@gmail.com>
References: <5079EB5B.8080102@hp.com>
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To: Chegu Vinod <chegu_vinod@hp.com>
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On 10/13/2012 06:29 PM, Chegu Vinod wrote:
> Hello,
> 
> Wanted to get a clarification about KVM_MAX_VCPUS(currently set to 254)
>  in kvm_host.h file. The kvm_vcpu *vcpus array is sized based on KVM_MAX_VCPUS.
> (i.e. a max of 254 elements in the array).
>  
> An 8bit APIC id should allow for 256 ID's. Reserving one for Broadcast should
> leave 255 ID's.  Is there one more ID reserved for some other purpose ? (hence
> leading to KVM_MAX_VCPUS being set to 254 and not 255).

Another ID goes to the IO-APIC.


Thanks,
Sasha