[PATCH] SVM: support writing 0 to K8 performance counter control registers

[PATCH] SVM: support writing 0 to K8 performance counter control registers

[Joerg Roedel]

This patch is a slightly improved version of a previously submitted patch. It
lets SVM ignore writes of the value 0 to the performance counter control
registers.  Thus enabling them will still fail in the guest.  This is required
to boot Windows Vista 64bit.

Signed-off-by: Joerg Roedel <joerg.roedel-5C7GfCeVMHo@public.gmane.org>
Signed-off-by: Markus Rechberger <markus.rechberger-5C7GfCeVMHo@public.gmane.org>
---
 drivers/kvm/svm.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index 9f8564a..f81b871 100644
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -1155,6 +1155,17 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 data)
 	case MSR_IA32_SYSENTER_ESP:
 		svm->vmcb->save.sysenter_esp = data;
 		break;
+	case MSR_K7_EVNTSEL0:
+	case MSR_K7_EVNTSEL1:
+	case MSR_K7_EVNTSEL2:
+	case MSR_K7_EVNTSEL3:
+		/*
+		 * only support writing 0 to the performance counters for now
+		 * to make Windows happy. Should be replaced by a real
+		 * performance counter emulation later.
+		 */
+		if (data == 0)
+			break;
 	default:
 		return kvm_set_msr_common(vcpu, ecx, data);
 	}
-- 
1.5.2.5




-------------------------------------------------------------------------
SF.Net email is sponsored by:
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://sourceforge.net/services/buy/index.php

Re: [PATCH] SVM: support writing 0 to K8 performance counter control registers

[Avi Kivity]

Joerg Roedel wrote:
> This patch is a slightly improved version of a previously submitted patch. It
> lets SVM ignore writes of the value 0 to the performance counter control
> registers.  Thus enabling them will still fail in the guest.  This is required
> to boot Windows Vista 64bit.
>
>   

Applied, thanks.

-- 
error compiling committee.c: too many arguments to function


-------------------------------------------------------------------------
SF.Net email is sponsored by:
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://sourceforge.net/services/buy/index.php

Re: [PATCH] SVM: support writing 0 to K8 performance counter control registers

[Avi Kivity]

Joerg Roedel wrote:
> This patch is a slightly improved version of a previously submitted patch. It
> lets SVM ignore writes of the value 0 to the performance counter control
> registers.  Thus enabling them will still fail in the guest.  This is required
> to boot Windows Vista 64bit.
>
> Signed-off-by: Joerg Roedel <joerg.roedel-5C7GfCeVMHo@public.gmane.org>
> Signed-off-by: Markus Rechberger <markus.rechberger-5C7GfCeVMHo@public.gmane.org>
> ---
>  drivers/kvm/svm.c |   11 +++++++++++
>  1 files changed, 11 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
> index 9f8564a..f81b871 100644
> --- a/drivers/kvm/svm.c
> +++ b/drivers/kvm/svm.c
> @@ -1155,6 +1155,17 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 data)
>  	case MSR_IA32_SYSENTER_ESP:
>  		svm->vmcb->save.sysenter_esp = data;
>  		break;
> +	case MSR_K7_EVNTSEL0:
> +	case MSR_K7_EVNTSEL1:
> +	case MSR_K7_EVNTSEL2:
> +	case MSR_K7_EVNTSEL3:
> +		/*
> +		 * only support writing 0 to the performance counters for now
> +		 * to make Windows happy. Should be replaced by a real
> +		 * performance counter emulation later.
> +		 */
> +		if (data == 0)
> +			break;
>  	default:
>  		return kvm_set_msr_common(vcpu, ecx, data);
>  	}
>   

I changed the fall-thru here to something more explicit, in case someone 
wants to add more msrs.


-- 
error compiling committee.c: too many arguments to function


-------------------------------------------------------------------------
SF.Net email is sponsored by:
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://sourceforge.net/services/buy/index.php