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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c33
1 files changed, 13 insertions, 20 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 13728dbdbb56..a60bdbccff51 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1441,20 +1441,8 @@ EXPORT_SYMBOL_GPL(kvm_write_tsc);
static cycle_t read_tsc(void)
{
- cycle_t ret;
- u64 last;
-
- /*
- * Empirically, a fence (of type that depends on the CPU)
- * before rdtsc is enough to ensure that rdtsc is ordered
- * with respect to loads. The various CPU manuals are unclear
- * as to whether rdtsc can be reordered with later loads,
- * but no one has ever seen it happen.
- */
- rdtsc_barrier();
- ret = (cycle_t)vget_cycles();
-
- last = pvclock_gtod_data.clock.cycle_last;
+ cycle_t ret = (cycle_t)rdtsc_ordered();
+ u64 last = pvclock_gtod_data.clock.cycle_last;
if (likely(ret >= last))
return ret;
@@ -1643,7 +1631,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
return 1;
}
if (!use_master_clock) {
- host_tsc = native_read_tsc();
+ host_tsc = rdtsc();
kernel_ns = get_kernel_ns();
}
@@ -1985,7 +1973,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if (guest_cpuid_has_tsc_adjust(vcpu)) {
if (!msr_info->host_initiated) {
s64 adj = data - vcpu->arch.ia32_tsc_adjust_msr;
- kvm_x86_ops->adjust_tsc_offset(vcpu, adj, true);
+ adjust_tsc_offset_guest(vcpu, adj);
}
vcpu->arch.ia32_tsc_adjust_msr = data;
}
@@ -2620,7 +2608,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
if (unlikely(vcpu->cpu != cpu) || check_tsc_unstable()) {
s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 :
- native_read_tsc() - vcpu->arch.last_host_tsc;
+ rdtsc() - vcpu->arch.last_host_tsc;
if (tsc_delta < 0)
mark_tsc_unstable("KVM discovered backwards TSC");
if (check_tsc_unstable()) {
@@ -2648,7 +2636,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
kvm_x86_ops->vcpu_put(vcpu);
kvm_put_guest_fpu(vcpu);
- vcpu->arch.last_host_tsc = native_read_tsc();
+ vcpu->arch.last_host_tsc = rdtsc();
}
static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
@@ -6083,6 +6071,7 @@ static void process_smi_save_state_64(struct kvm_vcpu *vcpu, char *buf)
static void process_smi(struct kvm_vcpu *vcpu)
{
struct kvm_segment cs, ds;
+ struct desc_ptr dt;
char buf[512];
u32 cr0;
@@ -6115,6 +6104,10 @@ static void process_smi(struct kvm_vcpu *vcpu)
kvm_x86_ops->set_cr4(vcpu, 0);
+ /* Undocumented: IDT limit is set to zero on entry to SMM. */
+ dt.address = dt.size = 0;
+ kvm_x86_ops->set_idt(vcpu, &dt);
+
__kvm_set_dr(vcpu, 7, DR7_FIXED_1);
cs.selector = (vcpu->arch.smbase >> 4) & 0xffff;
@@ -6384,7 +6377,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
hw_breakpoint_restore();
vcpu->arch.last_guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu,
- native_read_tsc());
+ rdtsc());
vcpu->mode = OUTSIDE_GUEST_MODE;
smp_wmb();
@@ -7193,7 +7186,7 @@ int kvm_arch_hardware_enable(void)
if (ret != 0)
return ret;
- local_tsc = native_read_tsc();
+ local_tsc = rdtsc();
stable = !check_tsc_unstable();
list_for_each_entry(kvm, &vm_list, vm_list) {
kvm_for_each_vcpu(i, vcpu, kvm) {