[26/29] nVMX: Additional TSC-offset handling

Commit Message

Nadav Har'El Jan. 27, 2011, 8:43 a.m. UTC

None

Patch

--- .before/arch/x86/kvm/vmx.c	2011-01-26 18:06:06.000000000 +0200
+++ .after/arch/x86/kvm/vmx.c	2011-01-26 18:06:06.000000000 +0200
@@ -1655,12 +1655,23 @@  static u64 guest_read_tsc(void)
 static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
 {
 	vmcs_write64(TSC_OFFSET, offset);
+	if (is_guest_mode(vcpu))
+		/*
+		 * We are only changing TSC_OFFSET when L2 is running if for
+		 * some reason L1 chose not to trap the TSC MSR. Since
+		 * prepare_vmcs12() does not copy tsc_offset, we need to also
+		 * set the vmcs12 field here.
+		 */
+		get_vmcs12_fields(vcpu)->tsc_offset = offset -
+			to_vmx(vcpu)->nested.vmcs01_fields->tsc_offset;
 }
 
 static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment)
 {
 	u64 offset = vmcs_read64(TSC_OFFSET);
 	vmcs_write64(TSC_OFFSET, offset + adjustment);
+	if (is_guest_mode(vcpu))
+		get_vmcs12_fields(vcpu)->tsc_offset += adjustment;
 }
 
 static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu)