svn commit: r349749 - stable/12/share/man/man9

[Ed Maste]

Author: emaste
Date: Thu Jul  4 19:52:50 2019
New Revision: 349749
URL: https://svnweb.freebsd.org/changeset/base/349749

Log:
  MFC r349239, r349241: update vm_map_protect.9
  
  Clarify that vm_map_protect cannot upgrade max_protection
  
  It's implied by the man page's RETURN VALUES section, but be explicit in
  the description that vm_map_protect can not set new protection bits that
  are already in each entry's max_protection.
  
  Clarify vm_map_protect max_protection downgrade
  
  As reported in review D20709 by brooks calling vm_map_protect to set a
  new max_protection value downgrades existing mappings if necessary (as
  opposed to returning an error).
  
  Sponsored by:	The FreeBSD Foundation

Modified:
  stable/12/share/man/man9/vm_map_protect.9
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/share/man/man9/vm_map_protect.9
==============================================================================
--- stable/12/share/man/man9/vm_map_protect.9	Thu Jul  4 19:46:58 2019	(r349748)
+++ stable/12/share/man/man9/vm_map_protect.9	Thu Jul  4 19:52:50 2019	(r349749)
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 19, 2003
+.Dd June 20, 2019
 .Dt VM_MAP_PROTECT 9
 .Os
 .Sh NAME
@@ -51,6 +51,11 @@ within the map
 .Fa map
 to
 .Fa new_prot .
+The value specified by
+.Fa new_prot
+may not include any protection bits that are not set in
+.Va max_protection
+on every entry within the range.
 .Pp
 If
 .Fa set_max
@@ -59,7 +64,12 @@ is TRUE,
 is treated as the new
 .Va max_protection
 setting for each underlying entry.
-Otherwise, only the
+Protection bits not included
+.Fa new_prot
+will be cleared from existing entries.
+If
+.Fa set_max
+is FALSE only the
 .Va protection
 field is affected.
 .Pp