AuroraMiddleware/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2024-12-22 19:00:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

powerpc: Fix float128 IFUNC relocations [BZ #21707]

Browse Source 
The patch proposed by Peter Bergner [1] to libgcc in order to fix
[BZ #21707] adds a dependency on a symbol provided by the loader,
forcing the loader to be linked to tests after libgcc was linked.

It also requires to read the thread pointer during IRELA relocations.

Tested on powerpc, powerpc64, powerpc64le, s390x and x86_64.

[1] https://sourceware.org/ml/libc-alpha/2017-06/msg01383.html

	[BZ #21707]
	* csu/libc-start.c (LIBC_START_MAIN): Perform IREL{,A}
	relocations before or after initializing the TCB on statically
	linked executables.  That's a per-architecture definition.
	* elf/rtld.c (dl_main): Add a comment about thread-local
	variables initialization.
	* sysdeps/generic/libc-start.h: New file.  Define
	ARCH_APPLY_IREL and ARCH_SETUP_IREL.
	* sysdeps/powerpc/Makefile:
	[$(subdir) = elf && $(multi-arch) != no] (tests-static-internal): Add tst-tlsifunc-static.
	[$(subdir) = elf && $(multi-arch) != no && $(build-shared) == yes]
	(tests-internal): Add tst-tlsifunc.
	* sysdeps/powerpc/tst-tlsifunc.c: New file.
	* sysdeps/powerpc/tst-tlsifunc-static.c: Likewise.
	* sysdeps/powerpc/powerpc64le/Makefile (f128-loader-link): New
	variable.
	[$(subdir) = math] (test-float128% test-ifloat128%): Force
	linking to the loader after linking to libgcc.
	[$(subdir) = wcsmbs || $(subdir) = stdlib] (bug-strtod bug-strtod2)
	(bug-strtod2 tst-strtod-round tst-wcstod-round tst-strtod6 tst-strrom)
	(tst-strfrom-locale strfrom-skeleton): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/libc-start.h: New file.  Define
	ARCH_APPLY_IREL and ARCH_SETUP_IREL.
This commit is contained in:
Tulio Magno Quites Machado Filho 2017-07-17 17:48:59 -03:00
parent ae5c498d93
commit 91ac3a7d84
9 changed files with 265 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
ChangeLog
View File

@ -1,3 +1,30 @@
2017-07-17 Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
[BZ #21707]
* csu/libc-start.c (LIBC_START_MAIN): Perform IREL{,A}
relocations before or after initializing the TCB on statically
linked executables. That's a per-architecture definition.
* elf/rtld.c (dl_main): Add a comment about thread-local
variables initialization.
* sysdeps/generic/libc-start.h: New file. Define
ARCH_APPLY_IREL and ARCH_SETUP_IREL.
* sysdeps/powerpc/Makefile:
[$(subdir) = elf && $(multi-arch) != no] (tests-static-internal): Add
tst-tlsifunc-static.
[$(subdir) = elf && $(multi-arch) != no && $(build-shared) == yes]
(tests-internal): Add tst-tlsifunc.
* sysdeps/powerpc/tst-tlsifunc.c: New file.
* sysdeps/powerpc/tst-tlsifunc-static.c: Likewise.
* sysdeps/powerpc/powerpc64le/Makefile (f128-loader-link): New
variable.
[$(subdir) = math] (test-float128% test-ifloat128%): Force
linking to the loader after linking to libgcc.
[$(subdir) = wcsmbs || $(subdir) = stdlib] (bug-strtod bug-strtod2)
(bug-strtod2 tst-strtod-round tst-wcstod-round tst-strtod6 tst-strrom)
(tst-strfrom-locale strfrom-skeleton): Likewise.
* sysdeps/unix/sysv/linux/powerpc/libc-start.h: New file. Define
ARCH_APPLY_IREL and ARCH_SETUP_IREL.
2017-07-17 DJ Delorie <dj@redhat.com>
* nss/nss_test.h: New.

11
csu/libc-start.c
View File

@ -108,6 +108,8 @@ apply_irel (void)
# define ARCH_INIT_CPU_FEATURES()
#endif
#include <libc-start.h>
STATIC int LIBC_START_MAIN (int (*main) (int, char **, char **
MAIN_AUXVEC_DECL),
int argc,
@ -189,11 +191,16 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
ARCH_INIT_CPU_FEATURES ();
/* Perform IREL{,A} relocations. */
apply_irel ();
ARCH_SETUP_IREL ();
/* The stack guard goes into the TCB, so initialize it early. */
__libc_setup_tls ();
/* In some architectures, IREL{,A} relocations happen after TLS setup in
order to let IFUNC resolvers benefit from TCB information, e.g. powerpc's
hwcap and platform fields available in the TCB. */
ARCH_APPLY_IREL ();
/* Set up the stack checker's canary. */
uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard (_dl_random);
# ifdef THREAD_SET_STACK_GUARD
@ -224,7 +231,7 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
__pointer_chk_guard_local = pointer_chk_guard;
# endif
#endif
#endif /* !SHARED */
/* Register the destructor of the dynamic linker if there is any. */
if (__glibc_likely (rtld_fini != NULL))

4
elf/rtld.c
View File

@ -2208,7 +2208,9 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n",
/* Now that we have completed relocation, the initializer data
for the TLS blocks has its final values and we can copy them
into the main thread's TLS area, which we allocated above. */
into the main thread's TLS area, which we allocated above.
Note: thread-local variables must only be accessed after completing
the next step. */
_dl_allocate_tls_init (tcbp);
/* And finally install it for the main thread. */

30
sysdeps/generic/libc-start.h Normal file
View File

@ -0,0 +1,30 @@
/* Generic definitions for libc main startup.
Copyright (C) 2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _LIBC_START_H
#define _LIBC_START_H
#ifndef SHARED
/* By default we perform STT_GNU_IFUNC resolution *before* TLS
initialization, and this means you cannot, without machine
knowledge, access TLS from an IFUNC resolver. */
#define ARCH_SETUP_IREL() apply_irel ()
#define ARCH_APPLY_IREL()
#endif /* ! SHARED */
#endif /* _LIBC_START_H */

10
sysdeps/powerpc/Makefile
View File

@ -11,7 +11,15 @@ sysdep-rtld-routines += dl-machine hwcapinfo
# Don't optimize GD tls sequence to LE.
LDFLAGS-tst-tlsopt-powerpc += -Wl,--no-tls-optimize
tests += tst-tlsopt-powerpc
endif
ifneq (no,$(multi-arch))
tests-static += tst-tlsifunc-static
tests-internal += tst-tlsifunc-static
ifeq (yes,$(build-shared))
tests-internal += tst-tlsifunc
endif # build-shared
endif # multi-arch
endif # subdir = elf
ifeq ($(subdir),setjmp)
ifeq (yes,$(build-shared))

10
sysdeps/powerpc/powerpc64le/Makefile
View File

@ -1,6 +1,11 @@
# When building float128 we need to ensure -mfloat128 is
# passed to all such object files.
# libgcc requires __tcb_parse_hwcap_and_convert_at_platform when built with
# a binary128 type. That symbol is provided by the loader on dynamically
# linked executables, forcing to link the loader after libgcc link.
f128-loader-link = $(as-needed) $(elf-objpfx)ld.so $(no-as-needed)
ifeq ($(subdir),math)
# sqrtf128 requires emulation before POWER9.
CPPFLAGS += -I../soft-fp
@ -11,6 +16,8 @@ $(foreach suf,$(all-object-suffixes),%f128_r$(suf)): CFLAGS += -mfloat128
$(foreach suf,$(all-object-suffixes),$(objpfx)test-float128%$(suf)): CFLAGS += -mfloat128
$(foreach suf,$(all-object-suffixes),$(objpfx)test-ifloat128%$(suf)): CFLAGS += -mfloat128
CFLAGS-libm-test-support-float128.c += -mfloat128
$(objpfx)test-float128% $(objpfx)test-ifloat128%: \
gnulib-tests += $(f128-loader-link)
endif
# Append flags to string <-> _Float128 routines.
@ -28,6 +35,9 @@ CFLAGS-tst-strtod6.c += -mfloat128
CFLAGS-tst-strfrom.c += -mfloat128
CFLAGS-tst-strfrom-locale.c += -mfloat128
CFLAGS-strfrom-skeleton.c += -mfloat128
$(foreach test,bug-strtod bug-strtod2 bug-strtod2 tst-strtod-round \
tst-wcstod-round tst-strtod6 tst-strrom tst-strfrom-locale \
strfrom-skeleton,$(objpfx)$(test)): gnulib-tests += $(f128-loader-link)
# When building glibc with support for _Float128, the powers of ten tables in
# fpioconst.c and in the string conversion functions must be extended. Some

19
sysdeps/powerpc/tst-tlsifunc-static.c Normal file
View File

@ -0,0 +1,19 @@
/* Test if an executable can read from the TLS from an STT_GNU_IFUNC resolver.
Copyright (C) 2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include "tst-tlsifunc.c"

129
sysdeps/powerpc/tst-tlsifunc.c Normal file
View File

@ -0,0 +1,129 @@
/* Test if an executable can read from the TLS from an STT_GNU_IFUNC resolver.
Copyright (C) 2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <libc-symbols.h>
#include <tls-macros.h>
__thread int bar;
static int *bar_ptr = NULL;
static uint32_t resolver_platform = 0;
int foo (void);
int tcb_test (void);
/* Offsets copied from tcb-offsets.h. */
#ifdef __powerpc64__
# define __TPREG "r13"
# define __ATPLATOFF -28764
#else
# define __TPREG "r2"
# define __ATPLATOFF -28724
#endif
uint32_t
get_platform (void)
{
register unsigned long tp __asm__ (__TPREG);
uint32_t tmp;
__asm__ ("lwz %0,%1(%2)\n"
: "=r" (tmp)
: "i" (__ATPLATOFF), "b" (tp));
return tmp;
}
void
init_foo (void)
{
bar_ptr = TLS_GD (bar);
}
int
my_foo (void)
{
printf ("&bar = %p and bar_ptr = %p.\n", &bar, bar_ptr);
return bar_ptr != NULL;
}
__ifunc (foo, foo, my_foo, void, init_foo);
void
init_tcb_test (void)
{
resolver_platform = get_platform ();
}
int
my_tcb_test (void)
{
printf ("resolver_platform = 0x%"PRIx32
" and current platform = 0x%"PRIx32".\n",
resolver_platform, get_platform ());
return resolver_platform != 0;
}
__ifunc (tcb_test, tcb_test, my_tcb_test, void, init_tcb_test);
static int
do_test (void)
{
int ret = 0;
if (foo ())
printf ("PASS: foo IFUNC resolver called once.\n");
else
{
printf ("FAIL: foo IFUNC resolver not called once.\n");
ret = 1;
}
if (&bar == bar_ptr)
printf ("PASS: bar address read from IFUNC resolver is correct.\n");
else
{
printf ("FAIL: bar address read from IFUNC resolver is incorrect.\n");
ret = 1;
}
if (tcb_test ())
printf ("PASS: tcb_test IFUNC resolver called once.\n");
else
{
printf ("FAIL: tcb_test IFUNC resolver not called once.\n");
ret = 1;
}
if (resolver_platform == get_platform ())
printf ("PASS: platform read from IFUNC resolver is correct.\n");
else
{
printf ("FAIL: platform read from IFUNC resolver is incorrect.\n");
ret = 1;
}
return ret;
}
#include <support/test-driver.c>

29
sysdeps/unix/sysv/linux/powerpc/libc-start.h Normal file
View File

@ -0,0 +1,29 @@
/* PowerPC definitions for libc main startup.
Copyright (C) 2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _LIBC_START_H
#define _LIBC_START_H
#ifndef SHARED
/* IREL{,A} must happen after TCB initialization in order to allow IFUNC
resolvers to read TCB fields, e.g. hwcap and at_platform. */
#define ARCH_SETUP_IREL()
#define ARCH_APPLY_IREL() apply_irel ()
#endif /* ! SHARED */
#endif /* _LIBC_START_H */