The history section (added in CSRG) claimed both first appeared in v6.
Looking at the manuals in the TUHS archive, /dev/mem was in v1 and
/dev/kmem was introduced in v5.
ok jan@
-.\" $OpenBSD: mem.4,v 1.6 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.7 2024/03/22 12:29:33 jsg Exp $
.\" Copyright (c) 1992, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\"
.\" from: @(#)mem.4 8.1 (Berkeley) 6/5/93
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 alpha
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
-.\" $OpenBSD: mem.4,v 1.6 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.7 2024/03/22 12:29:33 jsg Exp $
.\"
.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" from: @(#)mem.4 5.3 (Berkeley) 5/2/91
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 amd64
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
-.\" $OpenBSD: mem.4,v 1.12 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.13 2024/03/22 12:29:33 jsg Exp $
.\"
.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" from: @(#)mem.4 5.3 (Berkeley) 5/2/91
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 i386
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
-.\" $OpenBSD: mem.4,v 1.4 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.5 2024/03/22 12:29:33 jsg Exp $
.\"
.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" from: @(#)mem.4 5.3 (Berkeley) 5/2/91
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 landisk
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
-.\" $OpenBSD: mem.4,v 1.4 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.5 2024/03/22 12:29:33 jsg Exp $
.\" Copyright (c) 1992, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\"
.\" from: @(#)mem.4 8.1 (Berkeley) 6/5/93
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 loongson
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
-.\" $OpenBSD: mem.4,v 1.4 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.5 2024/03/22 12:29:33 jsg Exp $
.\" Copyright (c) 1992, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\"
.\" from: @(#)mem.4 8.1 (Berkeley) 6/5/93
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 luna88k
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
.\" SUCH DAMAGE.
.\"
.\" from: @(#)mem.4 8.1 (Berkeley) 6/5/93
-.\" $OpenBSD: mem.4,v 1.7 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.8 2024/03/22 12:29:33 jsg Exp $
.\" $NetBSD: mem.4,v 1.1 1997/06/08 17:40:57 ender Exp $
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 macppc
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .
-.\" $OpenBSD: mem.4,v 1.6 2018/01/12 04:36:44 deraadt Exp $
+.\" $OpenBSD: mem.4,v 1.7 2024/03/22 12:29:33 jsg Exp $
.\" Copyright (c) 1992, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\"
.\" from: @(#)mem.4 8.1 (Berkeley) 6/5/93
.\"
-.Dd $Mdocdate: January 12 2018 $
+.Dd $Mdocdate: March 22 2024 $
.Dt MEM 4 sparc64
.Os
.Sh NAME
.Sh HISTORY
The
.Pa /dev/mem
-and
+file appeared in
+.At v1 ,
.Pa /dev/kmem
-files appeared in
-.At v6 .
+appeared in
+.At v5 .