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diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile
--- a/share/man/man4/Makefile
+++ b/share/man/man4/Makefile
@@ -271,6 +271,7 @@
ktls.4 \
ktr.4 \
kue.4 \
+ ${_kvmclock.4} \
lagg.4 \
le.4 \
led.4 \
@@ -824,6 +825,7 @@
_imcsmb.4= imcsmb.4
_io.4= io.4
_itwd.4= itwd.4
+_kvmclock.4= kvmclock.4
_mgb.4= mgb.4
_nda.4= nda.4
_nfe.4= nfe.4
diff --git a/share/man/man4/kvmclock.4 b/share/man/man4/kvmclock.4
new file mode 100644
--- /dev/null
+++ b/share/man/man4/kvmclock.4
@@ -0,0 +1,93 @@
+.\" Copyright (c) 2023 Klara, Inc.
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd February 1, 2023
+.Dt KVMCLOCK 4
+.Os
+.Sh NAME
+.Nm kvmclock
+.Nd Para-virtualized clock driver for x86 KVM guests
+.Sh SYNOPSIS
+To compile this driver into the kernel,
+place the following lines in your
+kernel configuration file:
+.Bd -ragged -offset indent
+.Cd "device kvm_clock"
+.Ed
+.Sh DESCRIPTION
+This driver reads time-keeping information from the para-virtualized clock
+device provided by the KVM hypervisor on Linux hosts.
+The
+.Nm
+driver is only implemented on i386 and amd64 platforms.
+It acts as a
+.Xr timecounters 4
+device and is preferred over the Time Stamp Counter (TSC) when available.
+The driver exports timekeeping information via
+.Pa /dev/pvclock ,
+enabling the implementation of
+.Xr clock_gettime 2
+and related system calls without entering the kernel.
+.Pp
+The
+.Nm
+driver works by accessing a per-vCPU timekeeping structure maintained by the
+hypervisor.
+It uses a combination of TSC readings and information from the shared structure
+to produce a high-resolution timecounter which is invariant under hypervisor
+events such as vCPU migration and live VM migration.
+.Sh SYSCTL VARIABLES
+The following variables are available as both
+.Xr sysctl 8
+variables and
+.Xr loader 8
+tunables:
+.Bl -tag -width indent
+.It Va dev.kvmclock.0.vdso_enable_without_rdtscp
+By default, timekeeping information is exported to userspace only when the
+(virtual) CPU announces support for the
+.Dq rdtscp
+instruction.
+Setting this sysctl to 1 overrides this behaviour, allowing timekeeping
+information to be exported even in the absence of
+.Dq rdtscp
+support.
+However, this breaks compatibility with old copies of
+.Pa /usr/lib/libc.so
+and statically linked binaries which embed a copy of the system C library.
+Thus, this sysctl value should not be changed if the system may contain binaries
+older than the kernel.
+.It Va dev.kvmclock.0.vdso_force_unstable
+Mark the timecounter as unstable for userspace consumers.
+This is useful for debugging the driver and systems code and generally should
+not be touched.
+.El
+.Sh SEE ALSO
+.Xr timecounters 4
+.Sh HISTORY
+The
+.Nm
+driver first appeared in
+.Fx 13.1 .

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