In case AVIC is enabled, during vcpu_load/unload, SVM needs to update IOMMU IRTE with appropriate host physical APIC ID. Also, when vcpu_blocking/unblocking, SVM needs to update the is-running bit in the IOMMU IRTE. Both are achieved via calling amd_iommu_update_ga().
However, if GA mode is not enabled for the pass-through device, IOMMU driver will simply just return when calling amd_iommu_update_ga. Signed-off-by: Suravee Suthikulpanit <[email protected]> --- arch/x86/kvm/svm.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 5a0b89a..803351a 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1384,6 +1384,18 @@ free_avic: return err; } +static inline int +avic_update_iommu(struct kvm_vcpu *vcpu, int cpu, phys_addr_t pa, bool r) +{ + struct kvm_arch *vm_data = &vcpu->kvm->arch; + + if (!kvm_arch_has_assigned_device(vcpu->kvm)) + return 0; + + return amd_iommu_update_ga(vcpu->vcpu_id, cpu, vm_data->avic_tag, + (pa & AVIC_HPA_MASK), r); +} + /** * This function is called during VCPU halt/unhalt. */ @@ -1406,9 +1418,16 @@ static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run) WARN_ON(is_run == !!(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK)); entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; - if (is_run) + if (is_run) { entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; - WRITE_ONCE(*(svm->avic_physical_id_cache), entry); + WRITE_ONCE(*(svm->avic_physical_id_cache), entry); + avic_update_iommu(vcpu, h_physical_id, + page_to_phys(svm->avic_backing_page), 1); + } else { + avic_update_iommu(vcpu, h_physical_id, + page_to_phys(svm->avic_backing_page), 0); + WRITE_ONCE(*(svm->avic_physical_id_cache), entry); + } } static void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu) @@ -1435,6 +1454,9 @@ static void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu) entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; WRITE_ONCE(*(svm->avic_physical_id_cache), entry); + avic_update_iommu(vcpu, h_physical_id, + page_to_phys(svm->avic_backing_page), + svm->avic_is_running); } static void avic_vcpu_put(struct kvm_vcpu *vcpu) @@ -1446,6 +1468,10 @@ static void avic_vcpu_put(struct kvm_vcpu *vcpu) return; entry = READ_ONCE(*(svm->avic_physical_id_cache)); + if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK) + avic_update_iommu(vcpu, -1, + page_to_phys(svm->avic_backing_page), 0); + entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; WRITE_ONCE(*(svm->avic_physical_id_cache), entry); } -- 1.9.1
