From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: libc-hacker@sources.redhat.com
Subject: [patch] s390: remove pc relativ relocation from start.S.
Date: Fri, 05 May 2006 16:50:00 -0000 [thread overview]
Message-ID: <20060505165038.GA5543@skybase> (raw)
Hi,
while linking PIE executables an issue has been found with the startup
code for shared libs and pie executables. Scrt1.o is not position
independent since it contains a pc relative relocation against main()
in the .text segment. The attached patch fixes this.
blue skies,
Martin.
2006-05-05 Martin Schwidefsky <schwidefsky@de.ibm.com>
* sysdeps/s390/s390-32/elf/start.S: Replace pc relative relocation
by a GOT relocation to make Scrt1.o position independent.
* sysdeps/s390/s390-64/elf/start.S: Likewise.
diff -urpN libc/sysdeps/s390/s390-32/elf/start.S libc-s390/sysdeps/s390/s390-32/elf/start.S
--- libc/sysdeps/s390/s390-32/elf/start.S 2004-08-16 06:50:59.000000000 +0200
+++ libc-s390/sysdeps/s390/s390-32/elf/start.S 2006-05-05 16:24:43.000000000 +0200
@@ -1,5 +1,6 @@
/* Startup code compliant to the ELF s390 ABI.
- Copyright (C) 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2000, 2001, 2002, 2003, 2004, 2006
+ Free Software Foundation, Inc.
Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
This file is part of the GNU C Library.
@@ -88,9 +89,9 @@ _start:
l %r12,.L5-.Llit(%r13) # load .got pointer
la %r6,0(%r13,%r6)
la %r5,0(%r13,%r5)
- la %r2,0(%r13,%r2)
- la %r1,0(%r13,%r1)
la %r12,0(%r13,%r12)
+ l %r2,0(%r12,%r2)
+ la %r1,0(%r13,%r1)
#endif
/* ok, now branch to the libc main routine */
@@ -108,7 +109,7 @@ _start:
#else
.L1: .long __libc_csu_init-.Llit
.L2: .long __libc_csu_fini-.Llit
-.L3: .long main-.Llit
+.L3: .long main@GOT
.L4: .long __libc_start_main@plt-.Llit
.L5: .long _GLOBAL_OFFSET_TABLE_-.Llit
#endif
diff -urpN libc/sysdeps/s390/s390-64/elf/start.S libc-s390/sysdeps/s390/s390-64/elf/start.S
--- libc/sysdeps/s390/s390-64/elf/start.S 2004-08-16 06:50:55.000000000 +0200
+++ libc-s390/sysdeps/s390/s390-64/elf/start.S 2006-05-05 16:24:38.000000000 +0200
@@ -1,5 +1,5 @@
/* Startup code compliant to the 64 bit S/390 ELF ABI.
- Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
This file is part of the GNU C Library.
@@ -78,12 +78,14 @@ _start:
la %r7,160(%r15)
larl %r6,__libc_csu_fini # load pointer to __libc_csu_fini
larl %r5,__libc_csu_init # load pointer to __libc_csu_init
- larl %r2,main # load pointer to main
/* Ok, now branch to the libc main routine. */
#ifdef PIC
+ larl %r2,main@GOTENT # load pointer to main
+ lg %r2,0(%r2)
brasl %r14,__libc_start_main@plt
#else
+ larl %r2,main # load pointer to main
brasl %r14,__libc_start_main
#endif
next reply other threads:[~2006-05-05 16:50 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-05-05 16:50 Martin Schwidefsky [this message]
2006-05-05 18:26 ` Ulrich Drepper
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