From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Li <dli@virtualiron.com>
Subject: vmcs_revision_id: do we care?
Date: Tue, 08 Jan 2008 17:40:17 -0500
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Right now when xen finds out a SMP host has processors with different 
vmcs_revision_id, it considers it a bug.

xen/arch/x86/hvm/vmx/vmcs.c:vmx_init_vmcs_config():

rdmsr(MSR_IA32_VMX_BASIC_MSR, vmx_msr_low, vmx_msr_high);

if ( smp_processor_id() == 0 )
{
    vmcs_revision_id = vmx_msr_low;
}
else
{
    BUG_ON(vmcs_revision_id != vmx_msr_low);
}

Does anyone know why are we doing this? Can we change that check into a 
warning message?