diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 82a4a7884da5..98a2233bcd9a 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -48,8 +48,6 @@ SRCS+= brk.c
 SRCS+= pipe.c
 SRCS+= vadvise.c
 
-SRCS+=	compat-stub.c
-
 INTERPOSED = \
 	accept \
 	accept4 \
diff --git a/lib/libc/sys/Symbol.map b/lib/libc/sys/Symbol.map
index e2acb9344580..cb000cd4d4af 100644
--- a/lib/libc/sys/Symbol.map
+++ b/lib/libc/sys/Symbol.map
@@ -179,6 +179,8 @@ FBSD_1.0 {
 	munlockall;
 	munmap;
 	nanosleep;
+	netbsd_lchown;
+	netbsd_msync;
 	nfssvc;
 	nmount;
 	ntp_adjtime;
@@ -775,6 +777,10 @@ FBSDprivate_1.0 {
 	__sys_munmap;
 	_nanosleep;
 	__sys_nanosleep;
+	_netbsd_lchown;
+	__sys_netbsd_lchown;
+	_netbsd_msync;
+	__sys_netbsd_msync;
 	_nfssvc;
 	__sys_nfssvc;
 	_nmount;
diff --git a/lib/libc/sys/compat-stub.c b/lib/libc/sys/compat-stub.c
deleted file mode 100644
index 8a4da8474521..000000000000
--- a/lib/libc/sys/compat-stub.c
+++ /dev/null
@@ -1,50 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-2-Clause
- *
- * Copyright (c) 2018 SRI International
- * All rights reserved.
- *
- * This software was developed by SRI International and the University of
- * Cambridge Computer Laboratory (Department of Computer Science and
- * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
- * DARPA SSITH research programme.
- *
- * 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.
- *
- * $FreeBSD$
- */
-
-#include <sys/cdefs.h>
-#include <sys/types.h>
-#include <sys/errno.h>
-
-int compat_enosys(void);
-
-int
-compat_enosys(void)
-{
-
-	return (ENOSYS);
-}
-
-__sym_compat(netbsd_lchown, compat_enosys, FBSD_1.0);
-__sym_compat(netbsd_msync, compat_enosys, FBSD_1.0);
diff --git a/sys/compat/freebsd32/syscalls.master b/sys/compat/freebsd32/syscalls.master
index fb696abbd47e..363756e05ba0 100644
--- a/sys/compat/freebsd32/syscalls.master
+++ b/sys/compat/freebsd32/syscalls.master
@@ -499,10 +499,13 @@
 				    int count); }
 273	AUE_NULL	UNIMPL	nosys
 274	AUE_LCHMOD	NOPROTO	{ int lchmod(char *path, mode_t mode); }
-275	AUE_NULL	OBSOL	netbsd_lchown
+275	AUE_LCHOWN	NOPROTO	{ int lchown(char *path, uid_t uid, \
+				    gid_t gid); } netbsd_lchown \
+				    lchown_args int
 276	AUE_LUTIMES	STD	{ int freebsd32_lutimes(char *path, \
 				    struct timeval32 *tptr); }
-277	AUE_NULL	OBSOL	netbsd_msync
+277	AUE_MSYNC	NOPROTO	{ int msync(void *addr, size_t len, \
+				    int flags); } netbsd_msync msync_args int
 278	AUE_STAT  COMPAT11|NOPROTO { int nstat(char *path, struct nstat *ub); }
 279	AUE_FSTAT COMPAT11|NOPROTO { int nfstat(int fd, struct nstat *sb); }
 280	AUE_LSTAT COMPAT11|NOPROTO { int nlstat(char *path, struct nstat *ub); }
diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index 9ea0f1b5353b..6e23ef6e2332 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -630,10 +630,13 @@
 				    size_t count); }
 273	AUE_NULL	UNIMPL	nosys
 274	AUE_LCHMOD	STD	{ int lchmod(_In_z_ char *path, mode_t mode); }
-275	AUE_NULL	OBSOL	netbsd_lchown
+275	AUE_LCHOWN	NOPROTO	{ int lchown(char *path, uid_t uid, \
+				    gid_t gid); } netbsd_lchown lchown_args \
+				    int
 276	AUE_LUTIMES	STD	{ int lutimes(_In_z_ char *path, \
 				    _In_ struct timeval *tptr); }
-277	AUE_NULL	OBSOL	netbsd_msync
+277	AUE_MSYNC	NOPROTO	{ int msync(_In_ void *addr, size_t len, \
+				    int flags); } netbsd_msync msync_args int
 278	AUE_STAT	COMPAT11 { int nstat(_In_z_ char *path, \
 				    _Out_ struct nstat *ub); }
 279	AUE_FSTAT	COMPAT11 { int nfstat(int fd, _Out_ struct nstat *sb); }