RE: [PATCH v3 01/11] KVM: SVM: Introduce __set_intercept, __clr_intercept and __is_intercept

Babu Moger
2020-07-30T16:34:49Z

> -----Original Message-----
> From: kvm-owner@vger.kernel.org <kvm-owner@vger.kernel.org> On Behalf
> Of Paolo Bonzini
> Sent: Wednesday, July 29, 2020 6:09 PM
> To: Moger, Babu <Babu.Moger@amd.com>; vkuznets@redhat.com;
> wanpengli@tencent.com; sean.j.christopherson@intel.com;
> jmattson@google.com
> Cc: kvm@vger.kernel.org; joro@8bytes.org; x86@kernel.org; linux-
> kernel@vger.kernel.org; mingo@redhat.com; bp@alien8.de; hpa@zytor.com;
> tglx@linutronix.de
> Subject: Re: [PATCH v3 01/11] KVM: SVM: Introduce __set_intercept,
> __clr_intercept and __is_intercept
>
> On 29/07/20 01:37, Babu Moger wrote:
> > This is in preparation for the future intercept vector additions.
> >
> > Add new functions __set_intercept, __clr_intercept and __is_intercept
> > using kernel APIs __set_bit, __clear_bit and test_bit espectively.
> >
> > Signed-off-by: Babu Moger <babu.moger@amd.com>
> > ---
> > arch/x86/kvm/svm/svm.h | 15 +++++++++++++++
> > 1 file changed, 15 insertions(+)
> >
> > diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index
> > 6ac4c00a5d82..3b669718190a 100644
> > --- a/arch/x86/kvm/svm/svm.h
> > +++ b/arch/x86/kvm/svm/svm.h
> > @@ -217,6 +217,21 @@ static inline struct vmcb *get_host_vmcb(struct
> vcpu_svm *svm)
> > return svm->vmcb;
> > }
> >
> > +static inline void __set_intercept(void *addr, int bit) {
> > + __set_bit(bit, (unsigned long *)addr); }
> > +
> > +static inline void __clr_intercept(void *addr, int bit) {
> > + __clear_bit(bit, (unsigned long *)addr); }
> > +
> > +static inline bool __is_intercept(void *addr, int bit) {
> > + return test_bit(bit, (unsigned long *)addr); }
> > +
>
> Probably worth adding a range check?

Paolo,
Not sure. It is only called with intercept bits like __set_intercept(addr,
INTERCEPT_ xx). All these intercept bits are already accounted for.
Thanks

>
> > static inline void set_cr_intercept(struct vcpu_svm *svm, int bit) {
> > struct vmcb *vmcb = get_host_vmcb(svm);
> >