Re: [PATCH v2 09/15] svm: Add support for activate/deactivate AVIC at runtime

From: Alexander Graf
Date: Mon Aug 19 2019 - 06:28:57 EST




On 15.08.19 18:25, Suthikulpanit, Suravee wrote:
Add necessary logics for supporting activate/deactivate AVIC at runtime.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
arch/x86/kvm/svm.c | 27 +++++++++++++++++++++++++--
1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 47f2439..cfa4b13 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -385,6 +385,7 @@ struct amd_svm_iommu_ir {
static void svm_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa);
static void svm_complete_interrupts(struct vcpu_svm *svm);
static bool svm_get_enable_apicv(struct kvm *kvm);
+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);
@@ -2343,6 +2344,10 @@ 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_ACTIVATE, vcpu))
+ kvm_vcpu_activate_apicv(vcpu);
+ if (kvm_check_request(KVM_REQ_APICV_DEACTIVATE, vcpu))
+ kvm_vcpu_deactivate_apicv(vcpu);
avic_set_running(vcpu, true);
}
@@ -5182,10 +5187,19 @@ static void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb *vmcb = svm->vmcb;
- if (kvm_vcpu_apicv_active(vcpu))
+ if (kvm_vcpu_apicv_active(vcpu)) {
+ /**
+ * During AVIC temporary deactivation, guest could update
+ * APIC ID, DFR and LDR registers, which would not be trapped
+ * by avic_unaccelerated_ccess_interception(). In this case,

typo

Alex