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Message-Id: <200710261543.57111.rgetz@blackfin.uclinux.org>
Date: Fri, 26 Oct 2007 15:43:56 -0400
From: Robin Getz <rgetz@...ckfin.uclinux.org>
To: "Andrew Morton" <akpm@...ux-foundation.org>
Cc: "Jon Loeliger" <jdl@...escale.com>,
"David Woodhouse" <dwmw2@...radead.org>, paulus@...ba.org,
linux-kernel@...r.kernel.org
Subject: [patch] remove support for un-needed _extratext section
From: Robin Getz <rgetz@...ckfin.uclinux.org>
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.
arch/ppc/kernel/vmlinux.lds.S | 5 -----
include/asm-generic/sections.h | 2 --
kernel/kallsyms.c | 11 +----------
scripts/kallsyms.c | 12 +++---------
4 files changed, 4 insertions(+), 26 deletions(-)
Signed-off-by: Robin Getz <rgetz@...ckfin.uclinux.org>
cc: David Woodhouse <dwmw2@...radead.org>
cc: Jon Loeliger <jdl@...escale.com>
cc: Paul Mackerras <paulus@...ba.org>
----
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
Index: kernel/kallsyms.c
===================================================================
--- kernel/kallsyms.c (revision 3780)
+++ kernel/kallsyms.c (working copy)
@@ -48,14 +48,6 @@
return 0;
}
-static inline int is_kernel_extratext(unsigned long addr)
-{
- if (addr >= (unsigned long)_sextratext
- && addr <= (unsigned long)_eextratext)
- return 1;
- return 0;
-}
-
static inline int is_kernel_text(unsigned long addr)
{
if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext)
@@ -79,8 +71,7 @@
if (all_var)
return is_kernel(addr);
- return is_kernel_text(addr) || is_kernel_inittext(addr) ||
- is_kernel_extratext(addr);
+ return is_kernel_text(addr) || is_kernel_inittext(addr);
}
/* expand a compressed symbol data into the resulting uncompressed string,
Index: include/asm-generic/sections.h
===================================================================
--- include/asm-generic/sections.h (revision 3780)
+++ include/asm-generic/sections.h (working copy)
@@ -8,8 +8,6 @@
extern char __bss_start[], __bss_stop[];
extern char __init_begin[], __init_end[];
extern char _sinittext[], _einittext[];
-extern char _sextratext[] __attribute__((weak));
-extern char _eextratext[] __attribute__((weak));
extern char _end[];
extern char __per_cpu_start[], __per_cpu_end[];
extern char __kprobes_text_start[], __kprobes_text_end[];
Index: scripts/kallsyms.c
===================================================================
--- scripts/kallsyms.c (revision 3780)
+++ scripts/kallsyms.c (working copy)
@@ -45,7 +45,7 @@
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 unsigned long long _stext_l1, _etext_l1;
static int all_symbols = 0;
static char symbol_prefix_char = '\0';
@@ -104,10 +104,6 @@
_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 (strcmp(sym, "_stext_l1" ) == 0)
_stext_l1 = s->addr;
else if (strcmp(sym, "_etext_l1" ) == 0)
@@ -175,18 +171,16 @@
if (!all_symbols) {
if ((s->addr < _stext || s->addr > _etext)
&& (s->addr < _sinittext || s->addr > _einittext)
- && (s->addr < _sextratext || s->addr > _eextratext)
&& (s->addr < _stext_l1 || s->addr > _etext_l1))
return 0;
/* Corner case. Discard any symbols with the same value as
- * _etext _einittext or _eextratext; they can move between pass
+ * _etext; 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")))
+ (s->addr == _einittext && strcmp((char*)s->sym + offset, "_einittext")))
return 0;
}
Index: arch/ppc/kernel/vmlinux.lds.S
===================================================================
--- arch/ppc/kernel/vmlinux.lds.S (revision 3780)
+++ arch/ppc/kernel/vmlinux.lds.S (working copy)
@@ -144,11 +144,6 @@
. = ALIGN(4096);
__init_end = .;
-
- . = ALIGN(4096);
- _sextratext = .;
- _eextratext = .;
-
__bss_start = .;
.bss :
{
-
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