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authorNatanael Copa <ncopa@alpinelinux.org>2012-02-06 15:11:15 +0000
committerNatanael Copa <ncopa@alpinelinux.org>2012-02-07 07:22:42 +0000
commitd5f82899c4fb6072f992db6b1b19d9b6e26aeb95 (patch)
tree503f6c69ec0dfe32db9dafef2f9200661af6e822 /main/libc0.9.32/0007-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
parent754c0c888f81d4fab2e7cde320816ff901bd451e (diff)
downloadaports-d5f82899c4fb6072f992db6b1b19d9b6e26aeb95.tar.bz2
aports-d5f82899c4fb6072f992db6b1b19d9b6e26aeb95.tar.xz
main/libc0.9.32: upgrade to 0.9.33
Diffstat (limited to 'main/libc0.9.32/0007-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch')
-rw-r--r--main/libc0.9.32/0007-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch251
1 files changed, 251 insertions, 0 deletions
diff --git a/main/libc0.9.32/0007-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch b/main/libc0.9.32/0007-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
new file mode 100644
index 0000000000..ba3681f334
--- /dev/null
+++ b/main/libc0.9.32/0007-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
@@ -0,0 +1,251 @@
+From caed9d8dbc7e7b1e39a3e666d691d844da3ab12d Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
+Date: Thu, 10 Nov 2011 09:36:44 +0200
+Subject: [PATCH 7/8] libc/x86: fix stack unwinding and backtrace information
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+When compiled without framepointer, the DWARF-2 CFI data is required
+for proper stack unwinding.
+
+This patch adds the CFI information to:
+ * syscalls (so we get proper backtrace even for release builds)
+ the ebx hack was removed as it would complicate the CFI generation
+ * new thread stub function (so the backtrace is clean for user
+ created threads)
+
+Also pads the signal return trampolines separate from other functions.
+If CFI info was found for signal return code (which seems to happen if
+it's located right next a valid function), it will not be recognized
+as signal trampoline (gcc unwinder and gdb check first CFI info, and
+only if it does not exists it compares the exact opcode sequence to
+see if we are at signal return code block). This fixes a real crash
+if thread is cancelled and the cancellation handler fails to detect the
+signal return frame.
+
+Signed-off-by: Timo Teräs <timo.teras@iki.fi>
+Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
+---
+ libc/sysdeps/linux/i386/bits/syscalls.h | 82 +++----------------------------
+ libc/sysdeps/linux/i386/clone.S | 17 ++++++
+ libc/sysdeps/linux/i386/sigaction.c | 4 ++
+ 3 files changed, 28 insertions(+), 75 deletions(-)
+
+diff --git a/libc/sysdeps/linux/i386/bits/syscalls.h b/libc/sysdeps/linux/i386/bits/syscalls.h
+index 9fb4f35..35b09bb 100644
+--- a/libc/sysdeps/linux/i386/bits/syscalls.h
++++ b/libc/sysdeps/linux/i386/bits/syscalls.h
+@@ -13,6 +13,7 @@
+ #ifndef __ASSEMBLER__
+
+ #include <errno.h>
++#include <common/sysdep.h>
+
+ #define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
+ (__extension__ \
+@@ -32,90 +33,21 @@
+
+ #if 1 /* defined __PIC__ || defined __pic__ */
+
+-/* This code avoids pushing/popping ebx as much as possible.
+- * I think the main reason was that older GCCs had problems
+- * with proper saving/restoring of ebx if "b" constraint was used,
+- * which was breaking -fPIC code really badly.
+- * At least gcc 4.2.x seems to not need these tricks anymore,
+- * but this code is still useful because it often avoids
+- * using stack for saving ebx.
+- * Keeping it unconditionally enabled for now.
+- */
+-
+-/* We need some help from the assembler to generate optimal code.
+- * We define some macros here which later will be used. */
+-/* gcc>=4.6 with LTO need the same guards as IMA (a.k.a --combine) did.
+- * See gcc.gnu.org/PR47577 */
+-/* FIXME: drop these b* macros! */
+-
+-__asm__ (
+-#if defined __DOMULTI__ || __GNUC_PREREQ (4, 6)
+- /* Protect against asm macro redefinition (happens in __DOMULTI__ mode).
+- * Unfortunately, it ends up visible in .o files. */
+- ".ifndef _BITS_SYSCALLS_ASM\n\t"
+- ".set _BITS_SYSCALLS_ASM,1\n\t"
+-#endif
+- ".L__X'%ebx = 1\n\t"
+- ".L__X'%ecx = 2\n\t"
+- ".L__X'%edx = 2\n\t"
+- ".L__X'%eax = 3\n\t"
+- ".L__X'%esi = 3\n\t"
+- ".L__X'%edi = 3\n\t"
+- ".L__X'%ebp = 3\n\t"
+- ".L__X'%esp = 3\n\t"
+-
+- /* Loading param #1 (ebx) is done by loading it into
+- * another register, and then performing bpushl+bmovl,
+- * since we must preserve ebx */
+-
+- ".macro bpushl name reg\n\t"
+- ".if 1 - \\name\n\t" /* if reg!=ebx... */
+- ".if 2 - \\name\n\t" /* if reg can't be clobbered... */
+- "pushl %ebx\n\t" /* save ebx on stack */
+- ".else\n\t"
+- "xchgl \\reg, %ebx\n\t" /* else save ebx in reg, and load reg to ebx */
+- ".endif\n\t"
+- ".endif\n\t"
+- ".endm\n\t"
+-
+- ".macro bmovl name reg\n\t"
+- ".if 1 - \\name\n\t"
+- ".if 2 - \\name\n\t" /* if reg can't be clobbered... */
+- "movl \\reg, %ebx\n\t" /* load reg to ebx */
+- ".endif\n\t"
+- ".endif\n\t"
+- ".endm\n\t"
+-
+- ".macro bpopl name reg\n\t"
+- ".if 1 - \\name\n\t"
+- ".if 2 - \\name\n\t" /* if reg can't be clobbered... */
+- "popl %ebx\n\t" /* restore ebx from stack */
+- ".else\n\t"
+- "xchgl \\reg, %ebx\n\t" /* else restore ebx from reg */
+- ".endif\n\t"
+- ".endif\n\t"
+- ".endm\n\t"
+-
+-#if defined __DOMULTI__ || __GNUC_PREREQ (4, 6)
+- ".endif\n\t" /* _BITS_SYSCALLS_ASM */
+-#endif
+-);
+-
+ #define LOADARGS_0
+-#define LOADARGS_1 "bpushl .L__X'%k2, %k2\n\t" "bmovl .L__X'%k2, %k2\n\t"
++#define LOADARGS_1 "push %%ebx\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebx, 0) "\n\t" "movl %k2, %%ebx\n\t"
+ #define LOADARGS_2 LOADARGS_1
+ #define LOADARGS_3 LOADARGS_1
+ #define LOADARGS_4 LOADARGS_1
+ #define LOADARGS_5 LOADARGS_1
+-#define LOADARGS_6 LOADARGS_1 "push %%ebp\n\t" "movl %7, %%ebp\n\t"
++#define LOADARGS_6 LOADARGS_1 "push %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebp, 0) "\n\t" "movl %7, %%ebp\n\t"
+
+ #define RESTOREARGS_0
+-#define RESTOREARGS_1 "bpopl .L__X'%k2, %k2\n\t"
++#define RESTOREARGS_1 "pop %%ebx\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebx) "\n\t" RESTOREARGS_0
+ #define RESTOREARGS_2 RESTOREARGS_1
+ #define RESTOREARGS_3 RESTOREARGS_1
+ #define RESTOREARGS_4 RESTOREARGS_1
+ #define RESTOREARGS_5 RESTOREARGS_1
+-#define RESTOREARGS_6 "pop %%ebp\n\t" RESTOREARGS_1
++#define RESTOREARGS_6 "pop %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebp) "\n\t" RESTOREARGS_1
+
+ #define ASMFMT_0()
+ /* "acdSD" constraint would work too, but "SD" would use esi/edi and cause
+@@ -163,7 +95,7 @@ __asm__ (
+ #define LOADARGS_3
+ #define LOADARGS_4
+ #define LOADARGS_5
+-#define LOADARGS_6 "push %%ebp\n\t" "movl %7, %%ebp\n\t"
++#define LOADARGS_6 "push %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebp, 0) "\n\t" "movl %7, %%ebp\n\t"
+
+ #define RESTOREARGS_0
+ #define RESTOREARGS_1
+@@ -171,7 +103,7 @@ __asm__ (
+ #define RESTOREARGS_3
+ #define RESTOREARGS_4
+ #define RESTOREARGS_5
+-#define RESTOREARGS_6 "pop %%ebp\n\t"
++#define RESTOREARGS_6 "pop %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebp) "\n\t"
+
+ #define ASMFMT_0()
+ #define ASMFMT_1(arg1) \
+diff --git a/libc/sysdeps/linux/i386/clone.S b/libc/sysdeps/linux/i386/clone.S
+index a7de3fe..cf6cd35 100644
+--- a/libc/sysdeps/linux/i386/clone.S
++++ b/libc/sysdeps/linux/i386/clone.S
+@@ -25,6 +25,7 @@
+
+ #define _ERRNO_H 1
+ #include <bits/errno.h>
++#include <sysdep.h>
+ #include <sys/syscall.h>
+
+ /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
+@@ -45,6 +46,7 @@
+ .global clone
+ .type clone,%function
+ clone:
++ cfi_startproc;
+ /* Sanity check arguments. */
+ movl $-EINVAL,%eax
+
+@@ -86,17 +88,28 @@ clone:
+
+ /* Do the system call */
+ pushl %ebx
++ cfi_adjust_cfa_offset (4)
+ pushl %esi
++ cfi_adjust_cfa_offset (4)
+ pushl %edi
++ cfi_adjust_cfa_offset (4)
++
+ movl TLS+12(%esp),%esi
++ cfi_rel_offset (esi, 4)
+ movl PTID+12(%esp),%edx
+ movl FLAGS+12(%esp),%ebx
++ cfi_rel_offset (ebx, 8)
+ movl CTID+12(%esp),%edi
++ cfi_rel_offset (edi, 0)
+ movl $__NR_clone,%eax
+ #ifdef RESET_PID
+ /* Remember the flag value. */
+ movl %ebx, (%ecx)
+ #endif
++ /* End FDE now, because in the child the unwind info will be
++ wrong. */
++ cfi_endproc
++
+ int $0x80
+ popl %edi
+ popl %esi
+@@ -108,6 +121,9 @@ clone:
+ ret
+
+ .Lthread_start:
++ cfi_startproc;
++ /* Clearing frame pointer is insufficient, use CFI. */
++ cfi_undefined (eip);
+ /* Note: %esi is zero. */
+ movl %esi,%ebp /* terminate the stack frame */
+ call *%ebx
+@@ -120,6 +136,7 @@ clone:
+ movl %eax, %ebx
+ movl $__NR_exit, %eax
+ int $0x80
++ cfi_endproc;
+
+ /* Need to indirect jump to syscall error
+ * or we end up with TEXTREL's
+diff --git a/libc/sysdeps/linux/i386/sigaction.c b/libc/sysdeps/linux/i386/sigaction.c
+index a6a22de..1b787a6 100644
+--- a/libc/sysdeps/linux/i386/sigaction.c
++++ b/libc/sysdeps/linux/i386/sigaction.c
+@@ -120,6 +120,9 @@ libc_hidden_weak(sigaction)
+ # define RESTORE2(name, syscall) \
+ __asm__ ( \
+ ".text\n" \
++ ".align 8\n" \
++ " nop\n" \
++ ".align 16\n" \
+ "__" #name ":\n" \
+ " movl $" #syscall ", %eax\n" \
+ " int $0x80\n" \
+@@ -133,6 +136,7 @@ RESTORE(restore_rt, __NR_rt_sigreturn)
+ # define RESTORE2(name, syscall) \
+ __asm__ ( \
+ ".text\n" \
++ ".align 8\n" \
+ "__" #name ":\n" \
+ " popl %eax\n" \
+ " movl $" #syscall ", %eax\n" \
+--
+1.7.8.4
+