Attempt to locate an ELF header and symbol table directly after the kernel.

If it exists assume that the boot loader has provided a pointer to the end
of the symbol table. If it does not exist fall back to the previous
behaviour and expect that pointers to the symbol table have been provided
directly after the kernel.

ok miod@

1 files changed, 29 insertions, 14 deletions

diff --git a/sys/arch/sgi/sgi/machdep.c b/sys/arch/sgi/sgi/machdep.c
index 461c2360ea9..514002d1db6 100644
--- a/sys/arch/sgi/sgi/machdep.c
+++ b/sys/arch/sgi/sgi/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.57 2008/04/09 16:58:10 deraadt Exp $ */
+/*	$OpenBSD: machdep.c,v 1.58 2008/04/29 12:47:19 jsing Exp $ */
 
 /*
  * Copyright (c) 2003-2004 Opsycon AB  (www.opsycon.se / www.opsycon.com)
@@ -124,8 +124,7 @@ int	kbd_reset;
 int32_t *environment;
 struct sys_rec sys_config;
 
-
-/* ddb symbol init stuff */
+/* Pointers to the start and end of the symbol table. */
 caddr_t	ssym;
 caddr_t	esym;
 caddr_t	ekern;
@@ -134,7 +133,7 @@ struct phys_mem_desc mem_layout[MAXMEMSEGS];
 
 void crime_configure_memory(void);
 
-caddr_t mips_init(int, void *);
+caddr_t mips_init(int, void *, caddr_t);
 void initcpu(void);
 void dumpsys(void);
 void dumpconf(void);
@@ -151,7 +150,7 @@ static int atoi(const char *, int, const char **);
  */
 
 caddr_t
-mips_init(int argc, void *argv)
+mips_init(int argc, void *argv, caddr_t boot_esym)
 {
 	char *cp;
 	int i;
@@ -184,23 +183,39 @@ mips_init(int argc, void *argv)
 	bzero(edata, end - edata);
 
 	/*
-	 *  Reserve symbol table space. If invalid pointers no table.
+	 * Reserve space for the symbol table, if it exists.
 	 */
 	ssym = (char *)*(u_int64_t *)end;
-	esym = (char *)*((u_int64_t *)end + 1);
-	ekern = esym;
-	if (((long)ssym - (long)end) < 0 ||
-	    ((long)ssym - (long)end) > 0x1000 ||
-	    ssym[0] != ELFMAG0 || ssym[1] != ELFMAG1 ||
-	    ssym[2] != ELFMAG2 || ssym[3] != ELFMAG3 ) {
+
+	/* Attempt to locate ELF header and symbol table after kernel. */
+	if (end[0] == ELFMAG0 && end[1] == ELFMAG1 &&
+	    end[2] == ELFMAG2 && end[3] == ELFMAG3 ) {
+
+		/* ELF header exists directly after kernel. */
+		ssym = end;
+		esym = boot_esym;
+		ekern = esym;
+
+	} else if (((long)ssym - (long)end) >= 0 &&
+	    ((long)ssym - (long)end) <= 0x1000 &&
+	    ssym[0] == ELFMAG0 && ssym[1] == ELFMAG1 &&
+	    ssym[2] == ELFMAG2 && ssym[3] == ELFMAG3 ) {
+
+		/* Pointers exist directly after kernel. */
+		esym = (char *)*((u_int64_t *)end + 1);
+		ekern = esym;
+
+	} else {
+
+		/* Pointers aren't setup either... */
 		ssym = NULL;
 		esym = NULL;
 		ekern = end;
 	}
 
 	/*
-	 *  Initialize the system type and set up memory layout.
-	 *  Note that some systems have a more complex memory setup.
+	 * Initialize the system type and set up memory layout.
+	 * Note that some systems have a more complex memory setup.
 	 */
 	bios_ident();