[src/trunk]: src/share/man/man9 * Document the existing requirement that mach...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/63ed1a61eb95
branches:  trunk
changeset: 535305:63ed1a61eb95
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Wed Aug 14 15:25:50 2002 +0000

description:
* Document the existing requirement that machine-independent code
  not pmap_kenter_pa() a mapping at a virtual address for which a
  valid mapping already exists.
* Document the new requirement that machine-independent code not
  not pmap_kenter_pa() a mapping with VM_PROT_EXEC.

diffstat:

 share/man/man9/pmap.9 |  17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)

diffs (32 lines):

diff -r ae8b5f493f3b -r 63ed1a61eb95 share/man/man9/pmap.9
--- a/share/man/man9/pmap.9     Wed Aug 14 15:21:31 2002 +0000
+++ b/share/man/man9/pmap.9     Wed Aug 14 15:25:50 2002 +0000
@@ -1,6 +1,6 @@
-.\"    $NetBSD: pmap.9,v 1.14 2002/04/01 17:30:02 chs Exp $
+.\"    $NetBSD: pmap.9,v 1.15 2002/08/14 15:25:50 thorpej Exp $
 .\"
-.\" Copyright (c) 2000, 2001 The NetBSD Foundation, Inc.
+.\" Copyright (c) 2000, 2001, 2002 The NetBSD Foundation, Inc.
 .\" All rights reserved.
 .\"
 .\" This code is derived from software contributed to The NetBSD Foundation
@@ -558,7 +558,18 @@
 (such as
 .Fn pmap_page_protect ) Ns .
 Such mappings are also not included in the gathering of modified/referenced
-information about a page.  Mappings created with
+information about a page.  Mappings entered with
+.Fn pmap_kenter_pa
+by machine-independent code
+.Em must not
+have execute permission, as the
+data structures required to track execute permission of a page may not
+be available to
+.Fn pmap_kenter_pa .
+Machine-independent code is not allowed to enter a mapping with
+.Fn pmap_kenter_pa
+at a virtual address for which a valid mapping already exists.
+Mappings created with
 .Fn pmap_kenter_pa
 may be removed only with a call to
 .Fn pmap_kremove .