Messages in this thread |  | | Subject | Re: [PATCH 20/30] KVM: SVM: preserve VGIF across VMCB switch | From | Krish Sadhukhan <> | Date | Sun, 31 May 2020 16:11:36 -0700 |
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On 5/29/20 8:39 AM, Paolo Bonzini wrote: > There is only one GIF flag for the whole processor, so make sure it is not clobbered > when switching to L2 (in which case we also have to include the V_GIF_ENABLE_MASK, > lest we confuse enable_gif/disable_gif/gif_set). When going back, L1 could in > theory have entered L2 without issuing a CLGI so make sure the svm_set_gif is > done last, after svm->vmcb->control.int_ctl has been copied back from hsave. > > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > --- > arch/x86/kvm/svm/nested.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c > index 7e4a506828c9..6c7f0bffdf01 100644 > --- a/arch/x86/kvm/svm/nested.c > +++ b/arch/x86/kvm/svm/nested.c > @@ -293,6 +293,7 @@ static void nested_prepare_vmcb_save(struct vcpu_svm *svm, struct vmcb *nested_v > > static void nested_prepare_vmcb_control(struct vcpu_svm *svm) > { > + const u32 mask = V_INTR_MASKING_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK; > if (svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) > nested_svm_init_mmu_context(&svm->vcpu); > > @@ -308,7 +309,10 @@ static void nested_prepare_vmcb_control(struct vcpu_svm *svm) > svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset = > svm->vcpu.arch.l1_tsc_offset + svm->nested.ctl.tsc_offset; > > - svm->vmcb->control.int_ctl = svm->nested.ctl.int_ctl | V_INTR_MASKING_MASK; > + svm->vmcb->control.int_ctl = > + (svm->nested.ctl.int_ctl & ~mask) | > + (svm->nested.hsave->control.int_ctl & mask);
If this is the very first VMRUN, do we have any int_ctl saved in hsave ?
> + > svm->vmcb->control.virt_ext = svm->nested.ctl.virt_ext; > svm->vmcb->control.int_vector = svm->nested.ctl.int_vector; > svm->vmcb->control.int_state = svm->nested.ctl.int_state;
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