Index: sys/conf/files.amd64
===================================================================
--- sys/conf/files.amd64
+++ sys/conf/files.amd64
@@ -565,6 +565,7 @@
 x86/x86/intr_machdep.c		standard
 x86/x86/io_apic.c		standard
 x86/x86/kvm.c			standard
+x86/x86/kvm_clock.c		standard
 x86/x86/legacy.c		standard
 x86/x86/local_apic.c		standard
 x86/x86/mca.c			standard
Index: sys/conf/files.i386
===================================================================
--- sys/conf/files.i386
+++ sys/conf/files.i386
@@ -583,6 +583,7 @@
 x86/x86/intr_machdep.c		standard
 x86/x86/io_apic.c		optional apic
 x86/x86/kvm.c			standard
+x86/x86/kvm_clock.c		standard
 x86/x86/legacy.c		optional native
 x86/x86/local_apic.c		optional apic
 x86/x86/mca.c			standard
Index: sys/x86/include/kvm.h
===================================================================
--- sys/x86/include/kvm.h
+++ sys/x86/include/kvm.h
@@ -31,7 +31,19 @@
 
 #define KVM_CPUID_FEATURES_LEAF		0x40000001
 
+#define KVM_FEATURE_CLOCKSOURCE		0x00000001
+#define KVM_FEATURE_CLOCKSOURCE2	0x00000008
+
+/* Deprecated: for the CLOCKSOURCE feature. */
+#define KVM_MSR_WALL_CLOCK		0x11
+#define KVM_MSR_SYSTEM_TIME		0x12
+
+#define KVM_MSR_WALL_CLOCK_NEW		0x4b564d00
+#define KVM_MSR_SYSTEM_TIME_NEW		0x4b564d01
+
 int		kvm_paravirt_supported(void);
 uint32_t	kvm_get_features(void);
 
+uint64_t	kvm_clock_tsc_freq(void);
+
 #endif /* !_X86_KVM_H_ */
Index: sys/x86/x86/kvm_clock.c
===================================================================
--- /dev/null
+++ sys/x86/x86/kvm_clock.c
@@ -0,0 +1,132 @@
+/*-
+ * Copyright (c) 2014 Bryan Venteicher <bryanv@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/limits.h>
+#include <sys/systm.h>
+#include <sys/pcpu.h>
+#include <sys/smp.h>
+#include <sys/timetc.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <machine/pvclock.h>
+#include <x86/kvm.h>
+
+static u_int	kvm_clock_get_timecounter(struct timecounter *);
+static void	kvm_clock_pcpu_system_time(void *);
+
+DPCPU_DEFINE(struct pvclock_vcpu_time_info, kvm_clock_vcpu_time_info);
+
+static struct timecounter kvm_clock_timecounter = {
+	kvm_clock_get_timecounter,
+	NULL,
+	~0u,
+	1000000000ULL,
+	"KVMCLOCK",
+	1000,
+};
+
+static int		kvm_clock_registered;
+static uint32_t		kvm_clock_wall_clock_msr;
+static uint32_t		kvm_clock_system_time_msr;
+
+uint64_t
+kvm_clock_tsc_freq(void)
+{
+	struct pvclock_vcpu_time_info *ti;
+	uint64_t freq;
+
+	critical_enter();
+	ti = DPCPU_PTR(kvm_clock_vcpu_time_info);
+	freq = pvclock_tsc_freq(ti);
+	critical_exit();
+
+	return (freq);
+}
+
+static u_int
+kvm_clock_get_timecounter(struct timecounter *tc)
+{
+	struct pvclock_vcpu_time_info *ti;
+	uint64_t time;
+
+	critical_enter();
+	ti = DPCPU_PTR(kvm_clock_vcpu_time_info);
+	time = pvclock_get_timecount(ti);
+	critical_exit();
+
+	return (time & UINT_MAX);
+}
+
+static void
+kvm_clock_pcpu_system_time(void *arg)
+{
+	uint64_t data;
+	int enable;
+
+	enable = *(int *) arg;
+
+	if (enable != 0)
+		data = vtophys(DPCPU_PTR(kvm_clock_vcpu_time_info)) | 1;
+	else
+		data = 0;
+
+	wrmsr(kvm_clock_system_time_msr, data);
+}
+
+static void
+kvm_clock_init(void)
+{
+	uint32_t features;
+
+	if (vm_guest != VM_GUEST_KVM || !kvm_paravirt_supported())
+		return;
+
+	features = kvm_get_features();
+
+	if (features & KVM_FEATURE_CLOCKSOURCE2) {
+		kvm_clock_wall_clock_msr = KVM_MSR_WALL_CLOCK_NEW;
+		kvm_clock_system_time_msr = KVM_MSR_SYSTEM_TIME_NEW;
+	} else if (features & KVM_FEATURE_CLOCKSOURCE) {
+		kvm_clock_wall_clock_msr = KVM_MSR_WALL_CLOCK;
+		kvm_clock_system_time_msr = KVM_MSR_SYSTEM_TIME;
+	} else
+		return;
+
+	kvm_clock_registered = 1;
+	smp_rendezvous(smp_no_rendevous_barrier, kvm_clock_pcpu_system_time,
+	    smp_no_rendevous_barrier, &kvm_clock_registered);
+
+	tc_init(&kvm_clock_timecounter);
+}
+
+SYSINIT(kvm_clock, SI_SUB_SMP, SI_ORDER_ANY, kvm_clock_init, NULL);