KVM: SVM: Handle MCEs early in the vmexit process

This patch moves handling of the MC vmexits to an earlier
point in the vmexit. The handle_exit function is too late
because the vcpu might alreadry have changed its physical
cpu.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
(cherry picked from commit fe5913e4e1700cbfc337f4b1da9ddb26f6a55586)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 8e65552aa61ec3d3ba75d8921504eae0700b2e3e..a12c4618107b5788671af3d510234987fbd505b8 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1257,7 +1257,7 @@ static int nm_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
        return 1;
 }
 
-static int mc_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
+static void svm_handle_mce(struct vcpu_svm *svm)
 {
        /*
         * On an #MC intercept the MCE handler is not called automatically in
@@ -1267,6 +1267,11 @@ static int mc_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
                "int $0x12\n");
        /* not sure if we ever come back to this point */
 
+       return;
+}
+
+static int mc_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
+{
        return 1;
 }
 
@@ -2717,6 +2722,14 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                vcpu->arch.regs_avail &= ~(1 << VCPU_EXREG_PDPTR);
                vcpu->arch.regs_dirty &= ~(1 << VCPU_EXREG_PDPTR);
        }
+
+       /*
+        * We need to handle MC intercepts here before the vcpu has a chance to
+        * change the physical cpu
+        */
+       if (unlikely(svm->vmcb->control.exit_code ==
+                    SVM_EXIT_EXCP_BASE + MC_VECTOR))
+               svm_handle_mce(svm);
 }
 
 #undef R