From f0d6340cbafcec67edd845316f4dbe6dd3723e28 Mon Sep 17 00:00:00 2001
From: matthias <matthias@NetBSD.org>
Date: Thu, 7 Nov 1996 07:18:23 +0000
Subject: [PATCH] * Tell the vm system that kerneltext is mapped readonly.
 Stolen from atari/atari/machdep.c.

---
 sys/arch/pc532/pc532/machdep.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/sys/arch/pc532/pc532/machdep.c b/sys/arch/pc532/pc532/machdep.c
index 7ec2ede85288..53013f7bad7d 100644
--- a/sys/arch/pc532/pc532/machdep.c
+++ b/sys/arch/pc532/pc532/machdep.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: machdep.c,v 1.51 1996/10/13 03:30:45 christos Exp $	*/
+/*	$NetBSD: machdep.c,v 1.52 1996/11/07 07:18:23 matthias Exp $	*/
 
 /*-
  * Copyright (c) 1996 Matthias Pfaller.
@@ -148,6 +148,7 @@ void	cpu_reset __P((void));
 void
 cpu_startup()
 {
+	extern char etext[], kernel_text[];
 	unsigned i;
 	caddr_t v;
 	int sz;
@@ -236,6 +237,14 @@ cpu_startup()
 	mb_map = kmem_suballoc(kernel_map, (vm_offset_t *)&mbutl, &maxaddr,
 	    VM_MBUF_SIZE, FALSE);
 
+	/*
+	 * Tell the VM system that writing to kernel text isn't allowed.
+	 * If we don't, we might end up COW'ing the text segment!
+	 */
+	if (vm_map_protect(kernel_map, NBPG, ns532_round_page(&kernel_text),
+	    VM_PROT_READ|VM_PROT_EXECUTE, TRUE) != KERN_SUCCESS)
+		panic("can't protect kernel text");
+
 	/*
 	 * Initialize callouts
 	 */