KVM: SVM: Implement Flush-By-Asid feature

This patch adds the new flush-by-asid of upcoming AMD
processors to the KVM-AMD module.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7272b364580c..4dbc37204de1 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3158,7 +3158,6 @@ static void pre_svm_run(struct vcpu_svm *svm)
 
         struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
 
-        svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
         /* FIXME: handle wraparound of asid_generation */
         if (svm->asid_generation != sd->asid_generation)
                 new_asid(svm, sd);
@@ -3303,7 +3302,12 @@ static int svm_set_tss_addr(struct kvm *kvm, unsigned int addr)
 
 static void svm_flush_tlb(struct kvm_vcpu *vcpu)
 {
-        to_svm(vcpu)->asid_generation--;
+        struct vcpu_svm *svm = to_svm(vcpu);
+
+        if (static_cpu_has(X86_FEATURE_FLUSHBYASID))
+                svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID;
+        else
+                svm->asid_generation--;
 }
 
 static void svm_prepare_guest_switch(struct kvm_vcpu *vcpu)
@@ -3529,6 +3533,8 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
 
         svm->next_rip = 0;
 
+        svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
+
         /* if exit due to PF check for async PF */
         if (svm->vmcb->control.exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR)
                 svm->apf_reason = kvm_read_and_reset_pf_reason();