Re: [PATCH 2/2] KVM: x86: Preserve guest single-stepping on register

[Avi Kivity <avi@redhat.com>]

On 10/04/2009 09:02 PM, Jan Kiszka wrote:
>
> Hmmmm, good point. Mind reverting 2/2 and applying this one instead?
>
> Jan
>
> --------->
>
> KVM: x86: Rework guest single-step flag injection and filtering
>
> Push TF and RF injection and filtering on guest single-stepping into the
> vender get/set_rflags callbacks. This makes the whole mechanism more
> robust /wrt user space IOTCTL order and instruction emulations.
>
> Signed-off-by: Jan Kiszka<jan.kiszka@siemens.com>
> ---
>
>   arch/x86/kvm/svm.c |    8 +++++++-
>   arch/x86/kvm/vmx.c |    4 ++++
>   arch/x86/kvm/x86.c |   24 +++++++++---------------
>   3 files changed, 20 insertions(+), 16 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 279a2ae..407e1a7 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -797,11 +797,17 @@ static void svm_vcpu_put(struct kvm_vcpu *vcpu)
>
>   static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu)
>   {
> -	return to_svm(vcpu)->vmcb->save.rflags;
> +	unsigned long rflags = to_svm(vcpu)->vmcb->save.rflags;
> +
> +	if (vcpu->guest_debug&  KVM_GUESTDBG_SINGLESTEP)
> +		rflags&= ~(unsigned long)(X86_EFLAGS_TF | X86_EFLAGS_RF);
> +	return rflags;
>   }
>
>   static void svm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
>   {
> +	if (vcpu->guest_debug&  KVM_GUESTDBG_SINGLESTEP)
> +		rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
>   	to_svm(vcpu)->vmcb->save.rflags = rflags;
>   }
>    

This code is duplicated in vmx.  How about kvm_[gs]et_rflags to contain it?

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