From a85bcabd6942cf7e05273a93ba88109ce708039d Mon Sep 17 00:00:00 2001
From: niklas <niklas@openbsd.org>
Date: Sat, 4 May 1996 13:29:04 +0000
Subject: [PATCH] From NetBSD: Add a check in the kernel reload device
 (/dev/reload) to protect against the MMU switch code being in different
 locations between the running kernel and the new kernel.  Returns ENODEV if
 the reload fails. Change the error return from EFAULT to ENOEXEC when
 kernel_reload gets a short write on the exec header.

---
 sys/arch/amiga/amiga/locore.s | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/sys/arch/amiga/amiga/locore.s b/sys/arch/amiga/amiga/locore.s
index 443b93fa089..42ecc146601 100644
--- a/sys/arch/amiga/amiga/locore.s
+++ b/sys/arch/amiga/amiga/locore.s
@@ -1,5 +1,5 @@
-/*	$OpenBSD: locore.s,v 1.6 1996/05/02 06:43:18 niklas Exp $	*/
-/*	$NetBSD: locore.s,v 1.50 1996/04/21 21:07:04 veego Exp $	*/
+/*	$OpenBSD: locore.s,v 1.7 1996/05/04 13:29:04 niklas Exp $	*/
+/*	$NetBSD: locore.s,v 1.51 1996/05/02 02:08:33 mhitch Exp $	*/
 
 /*
  * Copyright (c) 1988 University of Utah.
@@ -841,9 +841,9 @@ Lcacheon:
  * Create a fake exception frame that returns to user mode,
  * make space for the rest of a fake saved register set, and
  * pass the first available RAM and a pointer to the register
- * set to "main()".  "main()" will do an "execve()" using that
+ * set to "mi_main()".  "mi_main()" will do an "execve()" using that
  * stack frame.
- * When "main()" returns, we're running in process 1 and have
+ * When "mi_main()" returns, we're running in process 1 and have
  * successfully executed the "execve()".  We load up the registers from
  * that set; the "rte" loads the PC and PSR, which jumps to "init".
  */
@@ -858,7 +858,7 @@ Lcacheon:
 	movl	usp,a1
 	movl	a1,sp@(FR_SP)		| save user stack pointer in frame
 	pea	sp@			| addr of space for D0 
-	jbsr	_main			| main(firstaddr, r0)
+	jbsr	_mi_main		| mi_main(firstaddr, r0)
 	addql	#4,sp			| pop args
 	cmpl	#MMU_68040,_mmutype	| 68040?
 	jne	Lnoflush		| no, skip
@@ -1842,6 +1842,14 @@ Ldoreset:
  */
 	.globl	_kernel_reload
 _kernel_reload:
+	lea	Lreload_copy,a0		| cursory validity check of new kernel
+	movl	a0@,d0			|  to see if the kernel reload code
+	addl	sp@(4),a0		|  in new image matches running kernel
+	cmpl	a0@,d0
+	jeq	Lreload_ok
+	rts				| It doesn't match - can't reload
+Lreload_ok:
+	jsr	_bootsync
 	CUSTOMADDR(a5)
 
 	movew	#(1<<9),a5@(0x096)	| disable DMA (before clobbering chipmem)
-- 
2.20.1