KVM: x86: Convert vapic synchronization to _cached functions (CVE-2013-6368)

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e8ba99c341808d6069b0b4f6985b8d71ef243971..ad6a01605aaa15f5a05f54bd11a88ce140702c2d 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3138,8 +3138,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
                r = -EFAULT;
                if (copy_from_user(&va, argp, sizeof va))
                        goto out;
-               r = 0;
-               kvm_lapic_set_vapic_addr(vcpu, va.vapic_addr);
+               r = kvm_lapic_set_vapic_addr(vcpu, va.vapic_addr);
                break;
        }
        case KVM_X86_SETUP_MCE: {
@@ -5539,36 +5538,6 @@ static void post_kvm_run_save(struct kvm_vcpu *vcpu)
                        !kvm_event_needs_reinjection(vcpu);
 }
 
-static int vapic_enter(struct kvm_vcpu *vcpu)
-{
-       struct kvm_lapic *apic = vcpu->arch.apic;
-       struct page *page;
-
-       if (!apic || !apic->vapic_addr)
-               return 0;
-
-       page = gfn_to_page(vcpu->kvm, apic->vapic_addr >> PAGE_SHIFT);
-       if (is_error_page(page))
-               return -EFAULT;
-
-       vcpu->arch.apic->vapic_page = page;
-       return 0;
-}
-
-static void vapic_exit(struct kvm_vcpu *vcpu)
-{
-       struct kvm_lapic *apic = vcpu->arch.apic;
-       int idx;
-
-       if (!apic || !apic->vapic_addr)
-               return;
-
-       idx = srcu_read_lock(&vcpu->kvm->srcu);
-       kvm_release_page_dirty(apic->vapic_page);
-       mark_page_dirty(vcpu->kvm, apic->vapic_addr >> PAGE_SHIFT);
-       srcu_read_unlock(&vcpu->kvm->srcu, idx);
-}
-
 static void update_cr8_intercept(struct kvm_vcpu *vcpu)
 {
        int max_irr, tpr;
@@ -5889,11 +5858,6 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
        struct kvm *kvm = vcpu->kvm;
 
        vcpu->srcu_idx = srcu_read_lock(&kvm->srcu);
-       r = vapic_enter(vcpu);
-       if (r) {
-               srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx);
-               return r;
-       }
 
        r = 1;
        while (r > 0) {
@@ -5951,8 +5915,6 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
 
        srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx);
 
-       vapic_exit(vcpu);
-
        return r;
 }