From 6c3e4422dd201c107948adc1b7615610d7381bcb Mon Sep 17 00:00:00 2001 From: Suravee Suthikulpanit Date: Thu, 14 Nov 2019 14:15:12 -0600 Subject: [PATCH] svm: Add support for dynamic APICv Add necessary logics to support (de)activate AVIC at runtime. Signed-off-by: Suravee Suthikulpanit Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm.c | 38 ++++++++++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index d85e29bc6ff1..3c211933a0a7 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -387,6 +387,7 @@ static u8 rsm_ins_bytes[] = "\x0f\xaa"; static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0); static void svm_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa); static void svm_complete_interrupts(struct vcpu_svm *svm); +static inline void avic_post_state_restore(struct kvm_vcpu *vcpu); static int nested_svm_exit_handled(struct vcpu_svm *svm); static int nested_svm_intercept(struct vcpu_svm *svm); @@ -1545,7 +1546,10 @@ static void avic_init_vmcb(struct vcpu_svm *svm) vmcb->control.avic_logical_id = lpa & AVIC_HPA_MASK; vmcb->control.avic_physical_id = ppa & AVIC_HPA_MASK; vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID_COUNT; - vmcb->control.int_ctl |= AVIC_ENABLE_MASK; + if (kvm_apicv_activated(svm->vcpu.kvm)) + vmcb->control.int_ctl |= AVIC_ENABLE_MASK; + else + vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK; } static void init_vmcb(struct vcpu_svm *svm) @@ -1752,21 +1756,24 @@ out: static int avic_init_backing_page(struct kvm_vcpu *vcpu) { - int ret; u64 *entry, new_entry; int id = vcpu->vcpu_id; struct vcpu_svm *svm = to_svm(vcpu); - ret = avic_update_access_page(vcpu->kvm, true); - if (ret) - return ret; - if (id >= AVIC_MAX_PHYSICAL_ID_COUNT) return -EINVAL; if (!svm->vcpu.arch.apic->regs) return -EINVAL; + if (kvm_apicv_activated(vcpu->kvm)) { + int ret; + + ret = avic_update_access_page(vcpu->kvm, true); + if (ret) + return ret; + } + svm->avic_backing_page = virt_to_page(svm->vcpu.arch.apic->regs); /* Setting AVIC backing page address in the phy APIC ID table */ @@ -2234,7 +2241,8 @@ static int svm_create_vcpu(struct kvm_vcpu *vcpu) /* We initialize this flag to true to make sure that the is_running * bit would be set the first time the vcpu is loaded. */ - svm->avic_is_running = true; + if (irqchip_in_kernel(vcpu->kvm) && kvm_apicv_activated(vcpu->kvm)) + svm->avic_is_running = true; svm->nested.hsave = page_address(hsave_page); @@ -2359,6 +2367,8 @@ static void svm_vcpu_blocking(struct kvm_vcpu *vcpu) static void svm_vcpu_unblocking(struct kvm_vcpu *vcpu) { + if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu)) + kvm_vcpu_update_apicv(vcpu); avic_set_running(vcpu, true); } @@ -5186,17 +5196,25 @@ out: return ret; } -/* Note: Currently only used by Hyper-V. */ static void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); struct vmcb *vmcb = svm->vmcb; bool activated = kvm_vcpu_apicv_active(vcpu); - if (activated) + if (activated) { + /** + * During AVIC temporary deactivation, guest could update + * APIC ID, DFR and LDR registers, which would not be trapped + * by avic_unaccelerated_access_interception(). In this case, + * we need to check and update the AVIC logical APIC ID table + * accordingly before re-activating. + */ + avic_post_state_restore(vcpu); vmcb->control.int_ctl |= AVIC_ENABLE_MASK; - else + } else { vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK; + } mark_dirty(vmcb, VMCB_AVIC); svm_set_pi_irte_mode(vcpu, activated); -- 2.30.2