Re: [PATCH 2/8] KVM: nSVM: rename nested 'vmcb' to vmcb_gpa in few places

[Maxim Levitsky]

On Thu, 2020-08-20 at 11:56 +0200, Paolo Bonzini wrote:
> On 20/08/20 11:13, Maxim Levitsky wrote:
> > No functional changes.
> > 
> > Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
> > ---
> >  arch/x86/kvm/svm/nested.c | 10 +++++-----
> >  arch/x86/kvm/svm/svm.c    | 13 +++++++------
> >  arch/x86/kvm/svm/svm.h    |  2 +-
> >  3 files changed, 13 insertions(+), 12 deletions(-)
> > 
> > diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
> > index fb68467e6049..d9755eab2199 100644
> > --- a/arch/x86/kvm/svm/nested.c
> > +++ b/arch/x86/kvm/svm/nested.c
> > @@ -431,7 +431,7 @@ int enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
> >  {
> >  	int ret;
> >  
> > -	svm->nested.vmcb = vmcb_gpa;
> > +	svm->nested.vmcb_gpa = vmcb_gpa;
> >  	load_nested_vmcb_control(svm, &nested_vmcb->control);
> >  	nested_prepare_vmcb_save(svm, nested_vmcb);
> >  	nested_prepare_vmcb_control(svm);
> > @@ -568,7 +568,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm)
> >  	struct vmcb *vmcb = svm->vmcb;
> >  	struct kvm_host_map map;
> >  
> > -	rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb), &map);
> > +	rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb_gpa), &map);
> >  	if (rc) {
> >  		if (rc == -EINVAL)
> >  			kvm_inject_gp(&svm->vcpu, 0);
> > @@ -579,7 +579,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm)
> >  
> >  	/* Exit Guest-Mode */
> >  	leave_guest_mode(&svm->vcpu);
> > -	svm->nested.vmcb = 0;
> > +	svm->nested.vmcb_gpa = 0;
> >  	WARN_ON_ONCE(svm->nested.nested_run_pending);
> >  
> >  	/* in case we halted in L2 */
> > @@ -1018,7 +1018,7 @@ static int svm_get_nested_state(struct kvm_vcpu *vcpu,
> >  
> >  	/* First fill in the header and copy it out.  */
> >  	if (is_guest_mode(vcpu)) {
> > -		kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb;
> > +		kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb_gpa;
> >  		kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
> >  		kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
> >  
> > @@ -1128,7 +1128,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
> >  	copy_vmcb_control_area(&hsave->control, &svm->vmcb->control);
> >  	hsave->save = save;
> >  
> > -	svm->nested.vmcb = kvm_state->hdr.svm.vmcb_pa;
> > +	svm->nested.vmcb_gpa = kvm_state->hdr.svm.vmcb_pa;
> >  	load_nested_vmcb_control(svm, &ctl);
> >  	nested_prepare_vmcb_control(svm);
> >  
> > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> > index 562a79e3e63a..4338d2a2596e 100644
> > --- a/arch/x86/kvm/svm/svm.c
> > +++ b/arch/x86/kvm/svm/svm.c
> > @@ -1102,7 +1102,7 @@ static void init_vmcb(struct vcpu_svm *svm)
> >  	}
> >  	svm->asid_generation = 0;
> >  
> > -	svm->nested.vmcb = 0;
> > +	svm->nested.vmcb_gpa = 0;
> >  	svm->vcpu.arch.hflags = 0;
> >  
> >  	if (!kvm_pause_in_guest(svm->vcpu.kvm)) {
> > @@ -3884,7 +3884,7 @@ static int svm_pre_enter_smm(struct kvm_vcpu *vcpu, char *smstate)
> >  		/* FED8h - SVM Guest */
> >  		put_smstate(u64, smstate, 0x7ed8, 1);
> >  		/* FEE0h - SVM Guest VMCB Physical Address */
> > -		put_smstate(u64, smstate, 0x7ee0, svm->nested.vmcb);
> > +		put_smstate(u64, smstate, 0x7ee0, svm->nested.vmcb_gpa);
> >  
> >  		svm->vmcb->save.rax = vcpu->arch.regs[VCPU_REGS_RAX];
> >  		svm->vmcb->save.rsp = vcpu->arch.regs[VCPU_REGS_RSP];
> > @@ -3903,17 +3903,18 @@ static int svm_pre_leave_smm(struct kvm_vcpu *vcpu, const char *smstate)
> >  	struct vmcb *nested_vmcb;
> >  	struct kvm_host_map map;
> >  	u64 guest;
> > -	u64 vmcb;
> > +	u64 vmcb_gpa;
> >  	int ret = 0;
> >  
> >  	guest = GET_SMSTATE(u64, smstate, 0x7ed8);
> > -	vmcb = GET_SMSTATE(u64, smstate, 0x7ee0);
> > +	vmcb_gpa = GET_SMSTATE(u64, smstate, 0x7ee0);
> >  
> >  	if (guest) {
> > -		if (kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb), &map) == -EINVAL)
> > +		if (kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb_gpa), &map) == -EINVAL)
> >  			return 1;
> > +
> >  		nested_vmcb = map.hva;
> > -		ret = enter_svm_guest_mode(svm, vmcb, nested_vmcb);
> > +		ret = enter_svm_guest_mode(svm, vmcb_gpa, nested_vmcb);
> >  		kvm_vcpu_unmap(&svm->vcpu, &map, true);
> >  	}
> >  
> > diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
> > index a798e1731709..03f2f082ef10 100644
> > --- a/arch/x86/kvm/svm/svm.h
> > +++ b/arch/x86/kvm/svm/svm.h
> > @@ -85,7 +85,7 @@ struct svm_nested_state {
> >  	struct vmcb *hsave;
> >  	u64 hsave_msr;
> >  	u64 vm_cr_msr;
> > -	u64 vmcb;
> > +	u64 vmcb_gpa;
> >  	u32 host_intercept_exceptions;
> >  
> >  	/* These are the merged vectors */
> > 
> 
> Please use vmcb12_gpa, and svm->nested.vmcb12 for the VMCB in patch 6.
> 
> (You probably also what to have local variables named vmcb12 in patch 6
> to avoid too-long lines).
The limit was raised to 100 chars recently, thats why I allowed some lines to
go over 80 characters to avoid adding too much noise.

> 
> Paolo

I was thinking to to this, but since this field already sits in ->nested I was
thinking that this is a bit redundant, but I don't have anything against doing it.

Best regards,
	Maxim Levitsky

>