From mboxrd@z Thu Jan  1 00:00:00 1970
From: Huang Ying <ying.huang@intel.com>
Subject: Re: [PATCH 1/2] KVM: Expose MCE control MSRs to userspace
Date: Thu, 08 Jul 2010 10:07:12 +0800
Message-ID: <1278554832.2783.2.camel@yhuang-dev.sh.intel.com>
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	 <1278500979-12725-2-git-send-email-avi@redhat.com>
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Cc: kvm@vger.kernel.org, Marcelo Tosatti <mtosatti@redhat.com>
To: Avi Kivity <avi@redhat.com>
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In-Reply-To: <1278500979-12725-2-git-send-email-avi@redhat.com>
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Hi, Avi,

On Wed, 2010-07-07 at 19:09 +0800, Avi Kivity wrote:
> Userspace needs to reset and save/restore these MSRs.
> 
> The MCE banks are not exposed since their number varies from vcpu to vcpu.
> 
> Signed-off-by: Avi Kivity <avi@redhat.com>
> ---
>  arch/x86/kvm/x86.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 7070b41..1e12cc5 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -744,6 +744,8 @@ static unsigned num_msrs_to_save;
>  
>  static u32 emulated_msrs[] = {
>  	MSR_IA32_MISC_ENABLE,
> +	MSR_IA32_MCG_STATUS,
> +	MSR_IA32_MCG_CTL,

We need only clear MSR_IA32_MCG_STATUS during reset, but should not
clear MSR_IA32_MCG_CTL.

>  };
>  
>  static int set_efer(struct kvm_vcpu *vcpu, u64 efer)

Best Regards,
Huang Ying