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

Maxim Levitsky
2020-08-20T11:57:22Z

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@redhat.com>
> > ---
> > 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

>