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+.\"
+.\" Copyright (c) 2020 Leandro Lupori <luporl@FreeBSD.org>
+.\"
+.\" 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 5, 2020
+.Dt KVM_KERNDISP 3
+.Os
+.Sh NAME
+.Nm kvm_kerndisp
+.Nd get kernel displacement
+.Sh LIBRARY
+.Lb libkvm
+.Sh SYNOPSIS
+.In kvm.h
+.Ft kssize_t
+.Fn kvm_kerndisp "kvm_t *kd"
+.Sh DESCRIPTION
+.Fn kvm_kerndisp
+returns the number of bytes by which the kernel referenced by
+.Fa kd
+is displaced.
+This is the difference between the kernel's base virtual address at run time
+and the kernel base virtual address specified in the kernel image file.
+.Pp
+Note that if the kernel is moved to a lower memory address,
+the displacement will be negative.
+.Sh RETURN VALUES
+.Fn kvm_kerndisp
+returns the number of bytes by which the kernel is displaced.
+If the kernel is not displaced or if it is not possible to find the
+displacement then 0 is returned.
+.Sh SEE ALSO
+.Xr kvm 3 ,
+.Xr kvm_close 3 ,
+.Xr kvm_open 3