remove support for un-needed _extratext section

When passing a zero address to kallsyms_lookup(), the kernel thought it was
a valid kernel address, even if it is not.  This is because is_ksym_addr()
called is_kernel_extratext() and checked against labels that don't exist on
many archs (which default as zero).  Since PPC was the only kernel which
defines _extra_text, (in 2005), and no longer needs it, this patch removes
_extra_text support.

For some history (provided by Jon):
 http://ozlabs.org/pipermail/linuxppc-dev/2005-September/019734.html
 http://ozlabs.org/pipermail/linuxppc-dev/2005-September/019736.html
 http://ozlabs.org/pipermail/linuxppc-dev/2005-September/019751.html

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jon Loeliger <jdl@freescale.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index 1f11d84..8fb8700 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -41,7 +41,7 @@
 
 static struct sym_entry *table;
 static unsigned int table_size, table_cnt;
-static unsigned long long _text, _stext, _etext, _sinittext, _einittext, _sextratext, _eextratext;
+static unsigned long long _text, _stext, _etext, _sinittext, _einittext;
 static int all_symbols = 0;
 static char symbol_prefix_char = '\0';
 
@@ -99,10 +99,6 @@
 		_sinittext = s->addr;
 	else if (strcmp(sym, "_einittext") == 0)
 		_einittext = s->addr;
-	else if (strcmp(sym, "_sextratext") == 0)
-		_sextratext = s->addr;
-	else if (strcmp(sym, "_eextratext") == 0)
-		_eextratext = s->addr;
 	else if (toupper(stype) == 'A')
 	{
 		/* Keep these useful absolute symbols */
@@ -165,18 +161,18 @@
 	 * and inittext sections are discarded */
 	if (!all_symbols) {
 		if ((s->addr < _stext || s->addr > _etext)
-		    && (s->addr < _sinittext || s->addr > _einittext)
-		    && (s->addr < _sextratext || s->addr > _eextratext))
+		    && (s->addr < _sinittext || s->addr > _einittext))
 			return 0;
 		/* Corner case.  Discard any symbols with the same value as
-		 * _etext _einittext or _eextratext; they can move between pass
-		 * 1 and 2 when the kallsyms data are added.  If these symbols
-		 * move then they may get dropped in pass 2, which breaks the
-		 * kallsyms rules.
+		 * _etext _einittext; they can move between pass 1 and 2 when
+		 * the kallsyms data are added.  If these symbols move then
+		 * they may get dropped in pass 2, which breaks the kallsyms
+		 * rules.
 		 */
-		if ((s->addr == _etext && strcmp((char*)s->sym + offset, "_etext")) ||
-		    (s->addr == _einittext && strcmp((char*)s->sym + offset, "_einittext")) ||
-		    (s->addr == _eextratext && strcmp((char*)s->sym + offset, "_eextratext")))
+		if ((s->addr == _etext &&
+				strcmp((char *)s->sym + offset, "_etext")) ||
+		    (s->addr == _einittext &&
+				strcmp((char *)s->sym + offset, "_einittext")))
 			return 0;
 	}