KVM: VMX: Fix host msr corruption with preemption enabled

[linux-2.6-omap-h63xx.git] / arch / x86 / kvm / vmx.c

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 02efbe75f317d68b8f24a6bd7945eaaeffcbfe89..540e95179074e8fccedd9802afdd0d81c21dccaa 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -566,7 +566,7 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu)
        load_transition_efer(vmx);
 }
 
-static void vmx_load_host_state(struct vcpu_vmx *vmx)
+static void __vmx_load_host_state(struct vcpu_vmx *vmx)
 {
        unsigned long flags;
 
@@ -596,6 +596,13 @@ static void vmx_load_host_state(struct vcpu_vmx *vmx)
        reload_host_efer(vmx);
 }
 
+static void vmx_load_host_state(struct vcpu_vmx *vmx)
+{
+       preempt_disable();
+       __vmx_load_host_state(vmx);
+       preempt_enable();
+}
+
 /*
  * Switches to specified vcpu, until a matching vcpu_put(), but assumes
  * vcpu mutex is already taken.
@@ -654,7 +661,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
 static void vmx_vcpu_put(struct kvm_vcpu *vcpu)
 {
-       vmx_load_host_state(to_vmx(vcpu));
+       __vmx_load_host_state(to_vmx(vcpu));
 }
 
 static void vmx_fpu_activate(struct kvm_vcpu *vcpu)
@@ -884,11 +891,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
        switch (msr_index) {
 #ifdef CONFIG_X86_64
        case MSR_EFER:
+               vmx_load_host_state(vmx);
                ret = kvm_set_msr_common(vcpu, msr_index, data);
-               if (vmx->host_state.loaded) {
-                       reload_host_efer(vmx);
-                       load_transition_efer(vmx);
-               }
                break;
        case MSR_FS_BASE:
                vmcs_writel(GUEST_FS_BASE, data);
@@ -910,11 +914,10 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
                guest_write_tsc(data);
                break;
        default:
+               vmx_load_host_state(vmx);
                msr = find_msr_entry(vmx, msr_index);
                if (msr) {
                        msr->data = data;
-                       if (vmx->host_state.loaded)
-                               load_msrs(vmx->guest_msrs, vmx->save_nmsrs);
                        break;
                }
                ret = kvm_set_msr_common(vcpu, msr_index, data);