From b22b377bd4ec234bc95a9d6359ba0f8d7264b4ae Mon Sep 17 00:00:00 2001
From: Mark Seaborn <mseaborn@chromium.org>
Date: Fri, 23 Apr 2010 17:31:01 +0100
Subject: [PATCH] mprotect.2: mention effect of READ_IMPLIES_EXEC personality
 flag

I puzzled over mprotect()'s effect on /proc/*/maps for a while
yesterday -- it was setting "x" without PROT_EXEC being specified.
Here is a patch to add some explanation.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
---
 man2/mprotect.2 | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/man2/mprotect.2 b/man2/mprotect.2
index 09c2d8acc..821850501 100644
--- a/man2/mprotect.2
+++ b/man2/mprotect.2
@@ -130,7 +130,15 @@ Whether
 .B PROT_EXEC
 has any effect different from
 .B PROT_READ
-is architecture- and kernel version-dependent.
+depends on processor architecture, kernel version, and process state. If
+.B READ_IMPLIES_EXEC
+is set in the process's personality flags (see
+.BR personality (2)),
+specifying
+.B PROT_READ
+will implicitly add
+.BR PROT_EXEC.
+
 On some hardware architectures (e.g., i386),
 .B PROT_WRITE
 implies