From: Vivek Goyal <vgoyal@in.ibm.com>
To: linux kernel mailing list <linux-kernel@vger.kernel.org>
Cc: Reloc Kernel List <fastboot@lists.osdl.org>,
ebiederm@xmission.com, akpm@osdl.org, ak@suse.de,
horms@verge.net.au, lace@jankratochvil.net, hpa@zytor.com,
magnus.damm@gmail.com, lwang@redhat.com, dzickus@redhat.com,
maneesh@in.ibm.com
Subject: [PATCH 9/12] kallsyms: Generate relocatable symbols
Date: Tue, 3 Oct 2006 13:21:04 -0400 [thread overview]
Message-ID: <20061003172104.GI3164@in.ibm.com> (raw)
In-Reply-To: <20061003170032.GA30036@in.ibm.com>
Print the addresses of non-absolute symbols relative to _text
so that ld will generate relocations. Allowing a relocatable
kernel to relocate them. We can't actually use the symbol names
because kallsyms includes static symbols that are not exported
from their object files.
Add the _text symbol definitions to the architectures which don't
define it otherwise linker will fail.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---
arch/h8300/kernel/vmlinux.lds.S | 1 +
arch/m68knommu/kernel/vmlinux.lds.S | 1 +
arch/powerpc/kernel/vmlinux.lds.S | 1 +
arch/ppc/kernel/vmlinux.lds.S | 1 +
arch/sparc/kernel/vmlinux.lds.S | 1 +
arch/sparc64/kernel/vmlinux.lds.S | 1 +
arch/v850/kernel/vmlinux.lds.S | 1 +
scripts/kallsyms.c | 20 +++++++++++++++++---
8 files changed, 24 insertions(+), 3 deletions(-)
diff -puN scripts/kallsyms.c~kallsyms.c-Generate-relocatable-symbols scripts/kallsyms.c
--- linux-2.6.18-git17/scripts/kallsyms.c~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/scripts/kallsyms.c 2006-10-02 13:17:59.000000000 -0400
@@ -43,7 +43,7 @@ struct sym_entry {
static struct sym_entry *table;
static unsigned int table_size, table_cnt;
-static unsigned long long _stext, _etext, _sinittext, _einittext, _sextratext, _eextratext;
+static unsigned long long _text, _stext, _etext, _sinittext, _einittext, _sextratext, _eextratext;
static int all_symbols = 0;
static char symbol_prefix_char = '\0';
@@ -91,7 +91,9 @@ static int read_symbol(FILE *in, struct
sym++;
/* Ignore most absolute/undefined (?) symbols. */
- if (strcmp(sym, "_stext") == 0)
+ if (strcmp(sym, "_text") == 0)
+ _text = s->addr;
+ else if (strcmp(sym, "_stext") == 0)
_stext = s->addr;
else if (strcmp(sym, "_etext") == 0)
_etext = s->addr;
@@ -265,9 +267,21 @@ static void write_src(void)
printf(".data\n");
+ /* Provide proper symbols relocatability by their '_text'
+ * relativeness. The symbol names cannot be used to construct
+ * normal symbol references as the list of symbols contains
+ * symbols that are declared static and are private to their
+ * .o files. This prevents .tmp_kallsyms.o or any other
+ * object from referencing them.
+ */
output_label("kallsyms_addresses");
for (i = 0; i < table_cnt; i++) {
- printf("\tPTR\t%#llx\n", table[i].addr);
+ if (toupper(table[i].sym[0]) != 'A') {
+ printf("\tPTR\t_text + %#llx\n",
+ table[i].addr - _text);
+ } else {
+ printf("\tPTR\t%#llx\n", table[i].addr);
+ }
}
printf("\n");
diff -puN arch/h8300/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/h8300/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/h8300/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/h8300/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -70,6 +70,7 @@ SECTIONS
#endif
.text :
{
+ _text = .;
#if defined(CONFIG_ROMKERNEL)
*(.int_redirect)
#endif
diff -puN arch/m68knommu/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/m68knommu/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/m68knommu/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/m68knommu/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -60,6 +60,7 @@ SECTIONS {
#endif
.text : {
+ _text = .;
_stext = . ;
*(.text)
SCHED_TEXT
diff -puN arch/powerpc/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/powerpc/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/powerpc/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/powerpc/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -33,6 +33,7 @@ SECTIONS
/* Text and gots */
.text : {
+ _text = .;
*(.text .text.*)
SCHED_TEXT
LOCK_TEXT
diff -puN arch/ppc/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/ppc/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/ppc/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/ppc/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -31,6 +31,7 @@ SECTIONS
.plt : { *(.plt) }
.text :
{
+ _text = .;
*(.text)
SCHED_TEXT
LOCK_TEXT
diff -puN arch/sparc64/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/sparc64/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/sparc64/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/sparc64/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -13,6 +13,7 @@ SECTIONS
. = 0x4000;
.text 0x0000000000404000 :
{
+ _text = .;
*(.text)
SCHED_TEXT
LOCK_TEXT
diff -puN arch/sparc/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/sparc/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/sparc/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/sparc/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -11,6 +11,7 @@ SECTIONS
. = 0x10000 + SIZEOF_HEADERS;
.text 0xf0004000 :
{
+ _text = .;
*(.text)
SCHED_TEXT
LOCK_TEXT
diff -puN arch/v850/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols arch/v850/kernel/vmlinux.lds.S
--- linux-2.6.18-git17/arch/v850/kernel/vmlinux.lds.S~kallsyms.c-Generate-relocatable-symbols 2006-10-02 13:17:59.000000000 -0400
+++ linux-2.6.18-git17-root/arch/v850/kernel/vmlinux.lds.S 2006-10-02 13:17:59.000000000 -0400
@@ -90,6 +90,7 @@
/* Kernel text segment, and some constant data areas. */
#define TEXT_CONTENTS \
+ _text = .; \
__stext = . ; \
*(.text) \
SCHED_TEXT \
_
next prev parent reply other threads:[~2006-10-03 17:31 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-10-03 17:00 [RFC][PATCH 0/12] ELF Relocatable x86 bzImage (V2) Vivek Goyal
2006-10-03 17:04 ` [PATCH 1/12] i386: Distinguish absolute symbols Vivek Goyal
2006-10-07 6:35 ` Andrew Morton
2006-10-08 16:47 ` Vivek Goyal
2006-10-09 7:35 ` Gerd Hoffmann
2006-10-09 13:49 ` Vivek Goyal
2006-10-03 17:06 ` [PATCH 2/12] i386: align data section to 4K boundary Vivek Goyal
2006-10-04 11:17 ` Andi Kleen
2006-10-04 15:18 ` H. Peter Anvin
2006-10-03 17:09 ` [PATCH 3/12] i386: Force section size to be non-zero to prevent a symbol becoming absolute Vivek Goyal
2006-10-04 11:02 ` Andi Kleen
2006-10-04 14:07 ` Eric W. Biederman
2006-10-04 14:45 ` Vivek Goyal
2006-10-04 16:09 ` Andrew Morton
2006-10-04 16:14 ` Vivek Goyal
2006-10-03 17:10 ` [PATCH 4/12] i386: define __pa_symbol() Vivek Goyal
2006-10-04 8:26 ` Franck Bui-Huu
2006-10-04 19:44 ` Vivek Goyal
2006-10-06 13:10 ` Franck Bui-Huu
2006-10-06 18:33 ` Vivek Goyal
2006-10-03 17:12 ` [PATCH 5/12] i386 setup.c: Reserve kernel memory starting from _text Vivek Goyal
2006-10-03 17:15 ` [PATCH 6/12] i386: CONFIG_PHYSICAL_START cleanup Vivek Goyal
2006-10-03 18:45 ` Dave Hansen
2006-10-03 18:52 ` Vivek Goyal
2006-10-03 18:59 ` Eric W. Biederman
2006-10-03 19:35 ` Vivek Goyal
2006-10-03 17:17 ` [PATCH 7/12] Make linux/elf.h safe to be included in assembly files Vivek Goyal
2006-10-03 17:19 ` [PATCH 8/12] elf: Add ELFOSABI_STANDALONE to elf.h Vivek Goyal
2006-10-03 17:21 ` Vivek Goyal [this message]
2006-10-03 17:22 ` [PATCH 10/12] i386: Relocatable kernel support Vivek Goyal
2006-10-03 17:24 ` [PATCH 11/12] i386: Implement CONFIG_PHYSICAL_ALIGN Vivek Goyal
2006-10-03 17:25 ` [PATCH 12/12] i386 boot: Add an ELF header to bzImage Vivek Goyal
2006-10-04 3:13 ` Andrew Morton
2006-10-04 4:28 ` Vivek Goyal
2006-10-04 4:40 ` H. Peter Anvin
2006-10-04 8:04 ` Eric W. Biederman
2006-10-04 15:18 ` H. Peter Anvin
2006-10-05 4:12 ` Eric W. Biederman
2006-10-05 4:17 ` H. Peter Anvin
2006-10-04 20:22 ` Vivek Goyal
2006-10-04 20:27 ` H. Peter Anvin
2006-10-04 20:48 ` Vivek Goyal
2006-10-04 20:52 ` H. Peter Anvin
2006-10-04 21:06 ` Vivek Goyal
2006-10-04 21:09 ` H. Peter Anvin
2006-10-04 5:37 ` Andrew Morton
2006-10-05 4:06 ` Eric W. Biederman
2006-10-05 4:12 ` H. Peter Anvin
2006-10-05 4:44 ` Andrew Morton
2006-10-05 6:13 ` Eric W. Biederman
2006-10-05 6:31 ` Andrew Morton
2006-10-05 6:48 ` Eric W. Biederman
2006-10-05 21:54 ` Vivek Goyal
2006-10-05 15:25 ` H. Peter Anvin
2006-10-05 15:35 ` Eric W. Biederman
2006-10-05 15:29 ` Eric W. Biederman
2006-10-05 15:44 ` H. Peter Anvin
2006-10-06 6:59 ` Andrew Morton
2006-10-06 12:56 ` Eric W. Biederman
2006-10-06 18:38 ` Vivek Goyal
2006-10-06 18:54 ` H. Peter Anvin
2006-10-06 19:09 ` Eric W. Biederman
2006-10-06 21:54 ` H. Peter Anvin
2006-10-09 14:33 ` Vivek Goyal
2006-10-10 3:14 ` Andrew Morton
2006-10-10 4:51 ` Eric W. Biederman
2006-10-10 14:30 ` Vivek Goyal
2006-10-10 18:46 ` Andrew Morton
2006-10-10 21:40 ` Vivek Goyal
2006-10-11 2:35 ` Andrew Morton
2006-10-06 19:01 ` Eric W. Biederman
2006-10-04 7:08 ` Eric W. Biederman
2006-10-04 14:23 ` Vivek Goyal
2006-10-05 3:09 ` Eric W. Biederman
2006-10-04 17:03 ` Vivek Goyal
2006-10-05 6:25 ` Eric W. Biederman
2006-10-05 21:34 ` Vivek Goyal
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