The s390 ABI requires the stack pointer to be aligned at 8-bytes.
When a program is invoked as an argument to the dynamic linker,
_dl_start_user adjusts the stack to remove the dynamic linker
arguments so that the program sees only its name and arguments. This
may result in the stack being misaligned since each argument shift is
only a word and not a double-word.
This is now fixed shifting argv and envp down instead of shifting argc
up and reclaiming the stack. This requires _dl_argv to be adjusted
and hence, is no longer relro.
Modifies the test examination in test-skeleton.c so that a test can be
successful if it is interrupted or it returns uninterrupted with the
expected status. For this both EXPECTED_SIGNAL and EXPECTED_STATUS
have to be set, as is done in tst-strcoll-overflow.c.
Continuing the removal of unused __libc_* function names, this patch
removes the __libc_waitpid name.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch; __waitpid, which is exported from
shared libc, changes from weak to strong on some configurations, which
is of no significance).
* include/sys/wait.h (__libc_waitpid): Remove declaration.
* posix/waitpid.c (__libc_waitpid): Rename to __waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
* sysdeps/unix/bsd/waitpid.c (__libc_waitpid): Rename to
__waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
* sysdeps/unix/sysv/linux/i386/syscalls.list (waitpid): Remove
__libc_waitpid alias.
* sysdeps/unix/sysv/linux/m68k/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/powerpc/syscalls.list (waitpid):
Likewise.
* sysdeps/unix/sysv/linux/sh/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/sparc/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/tile/waitpid.S (__libc_waitpid): Remove
alias.
* sysdeps/unix/sysv/linux/waitpid.c (__libc_waitpid): Rename to
__waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
We add Linux-realted comments about the atomicity of
write with respect to file offsets. As of Linux 3.14
the file offset update is atomic. That means that
multiple threads calling the write syscall can not possibly
get the same file offset. Therefore the writes should
not overlap and data should not be lost as is required
by POSIX.
For maximum paranoia we run ld.so through the normal set
of tests for all of the shared libraries. This includes
running ld.so through check-localplt, check-textrel, and
check-execstack. While none of these should trigger any
failures given the way ld.so is built, it might possibly
fail if a developer does something wrong. This paranoia
was triggered by a discussion over the use of __strcpy
vs. strcpy [1] and if the symbol could leak and use the
libc.so version.
The check-localplt test fails right away because localplt.data
needs updating for all arches. By default we add 6 new symbols:
__tls_get_addr, __libc_memalign, malloc, calloc, realloc and
free. Other machines like i386, power, and s390 require some
different symbol sets e.g. ___tls_get_addr vs. __tls_get_addr
for i386.
Verified for i386
Verified for x86_64
Verified for ppc32
Verified for ppc64
Verified for ppc64le
Verified for arm
Verified for aarch64
Verified for s390
Verified for s390x
Guessed for alpha
Guessed for ia64
Guessed for m68k
Guessed for microblaze
Guessed for sparc32
Guessed for sparc64
Defaults for sh
Defaults for mips
Defaults for hppa
Defaults for tile
Machine manintainers notified to double check the data
used in localplt.data.
[1] https://sourceware.org/ml/libc-alpha/2014-10/msg00548.html
Completing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch removes the final use - that for _dl_starting_up - replacing it
by rtld_hidden_def / rtld_hidden_proto. Having removed the last use,
the mechanism itself is also removed.
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch. (This is not much of a test since this
variable is only defined and used in the !HAVE_INLINED_SYSCALLS case.)
[BZ #14132]
* include/libc-symbols.h (INTUSE): Remove macro.
(INTDEF): Likewise.
(INTVARDEF): Likewise.
(_INTVARDEF): Likewise.
(INTDEF2): Likewise.
(INTVARDEF2): Likewise.
* elf/rtld.c [!HAVE_INLINED_SYSCALLS] (_dl_starting_up): Use
rtld_hidden_def instead of INTVARDEF.
* sysdeps/generic/ldsodefs.h [IS_IN_rtld]
(_dl_starting_up_internal): Remove declaration.
(_dl_starting_up): Use rtld_hidden_proto.
* elf/dl-init.c [!HAVE_INLINED_SYSCALLS] (_dl_starting_up): Remove
declaration.
[!HAVE_INLINED_SYSCALLS] (_dl_starting_up_internal): Likewise.
(_dl_init) [!HAVE_INLINED_SYSCALLS]: Don't use INTUSE with
_dl_starting_up.
* elf/dl-writev.h (_dl_writev): Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.h [!HAVE_INLINED_SYSCALLS]
(DL_STARTING_UP_DEF): Use __GI__dl_starting_up instead of
_dl_starting_up_internal.
Add a microbenchmark for measuring malloc and free performance with
varying numbers of threads. The benchmark allocates and frees buffers
of random sizes in a random order and measures the overall execution
time and RSS. Variants of the benchmark are run with 1, 8, 16 and
32 threads.
The random block sizes used follow an inverse square distribution
which is intended to mimic the behaviour of real applications which
tend to allocate many more small blocks than large ones.
ChangeLog:
2014-11-05 Will Newton <will.newton@linaro.org>
* benchtests/Makefile: (bench-malloc): Add malloc thread
scalability benchmark.
* benchtests/bench-malloc-threads.c: New file.
Here is an optimized implementation of __strchrnul. The
simplification that we don't have to track precisely why the loop
terminates (match or end-of-string) means we have to do less work in
both setup and the core inner loop. That means this should never be
slower than strchr.
As with strchr, the use of LD1 means we do not need different versions
for big-/little-endian.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch replaces its use for _dl_mcount with use of rtld_hidden_def /
rtld_hidden_proto.
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* elf/dl-profile.c (_dl_mcount): Use rtld_hidden_def instead of
INTDEF.
* sysdeps/generic/ldsodefs.h (_dl_mcount_internal): Remove
declaration.
(_dl_mcount): Use rtld_hidden_proto.
* elf/dl-runtime.c (_dl_profile_fixup): Don't use INTUSE with
_dl_mcount.
* elf/rtld.c (_rtld_global_ro): Likewise.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch eliminates its use for _dl_init. Since _dl_init was already
declared with hidden visibility, creating a second hidden alias for it
was completely pointless, so this patch replaces all uses of
_dl_init_internal with plain _dl_init instead of using hidden_proto /
hidden_def (which are only needed when you want a hidden alias for a
non-hidden symbol; it's quite possible there are cases where they are
used but don't need to be because the symbol in question is not part
of the public ABI and is only used within a single library, so using
attributes_hidden instead would suffice).
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* elf/dl-init.c (_dl_init): Don't use INTDEF.
* sysdeps/aarch64/dl-machine.h (RTLD_START): Use _dl_init instead
of _dl_init_internal.
* sysdeps/alpha/dl-machine.h (RTLD_START): Likewise.
* sysdeps/arm/dl-machine.h (RTLD_START): Likewise.
* sysdeps/hppa/dl-machine.h (RTLD_START): Likewise.
* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
* sysdeps/ia64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/m68k/dl-machine.h (RTLD_START): Likewise.
* sysdeps/microblaze/dl-machine.h (RTLD_START): Likewise.
* sysdeps/mips/dl-machine.h (RTLD_START): Likewise.
* sysdeps/powerpc/powerpc32/dl-start.S (_start): Likewise.
* sysdeps/s390/s390-32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/s390/s390-64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sh/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/tile/dl-start.S (_start): Likewise.
* sysdeps/x86_64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/x86_64/x32/dl-machine.h (RTLD_START): Likewise.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch replaces its use for _dl_argv with rtld_hidden_data_def and
rtld_hidden_proto. Some places in .S files that previously used
_dl_argv_internal or INTUSE(_dl_argv) now use __GI__dl_argv directly
(there are plenty of existing examples of such direct use of __GI_*).
A single place in rtld.c previously used _dl_argv without INTUSE,
apparently accidentally, while the rtld_hidden_proto mechanism avoids
such accidential omissions. As a consequence, this patch *does*
change the contents of stripped ld.so. However, the installed
stripped shared libraries are identical to those you get if instead of
this patch you change that single _dl_argv use to use INTUSE, without
any other changes.
Tested for x86_64 (testsuite as well as comparison of installed
stripped shared libraries as described above).
[BZ #14132]
* sysdeps/generic/ldsodefs.h (_dl_argv): Use rtld_hidden_proto.
[IS_IN_rtld] (_dl_argv_internal): Do not declare.
(rtld_progname): Make macro definition unconditional.
* elf/rtld.c (_dl_argv): Use rtld_hidden_data_def instead of
INTDEF.
(dlmopen_doit): Do not use INTUSE with _dl_argv.
(dl_main): Likewise.
* elf/dl-sysdep.c (_dl_sysdep_start): Likewise.
* sysdeps/alpha/dl-machine.h (RTLD_START): Use __GI__dl_argv
instead of _dl_argv_internal.
* sysdeps/powerpc/powerpc32/dl-start.S (_dl_start_user): Use
__GI__dl_argv instead of INTUSE(_dl_argv).
* sysdeps/powerpc/powerpc64/dl-machine.h (RTLD_START): Use
__GI__dl_argv instead of _dl_argv_internal.
Continuing the series of patches adding soft-fp features from the
kernel version of soft-fp to glibc so that glibc's version is able to
replace the old fork of soft-fp in the kernel, this patch adds the
last major such feature: _FP_TO_INT_ROUND, converting a floating-point
number to an integer with rounding according to the current rounding
direction (as opposed to truncating towards zero, which _FP_TO_INT
does).
The general structure of the implementation follows that of
_FP_TO_INT, but of course is more complicated. As with glibc's
_FP_TO_INT it works with raw input (the kernel versions of these
macros predate the conversion of _FP_TO_INT and many other macros to
raw or semi-raw input). I have not tried to work out what bugs there
might be in the kernel version that this might fix; it's a
from-scratch implementation based on _FP_TO_INT.
Tested for powerpc (soft-float) that there is no change to the
installed shared libraries; also tested with the libm tests with lrint
/ lrintf / llrint / llrintf made to use _FP_TO_INT_ROUND, to provide
some test of the functionality. As we don't have benchmarks for those
functions, I haven't actually included the soft-fp versions of them,
although I expect them to be faster than the existing code (given that
the existing code involves adding and subtracting numbers such as
0x1p52 to achieve the desired rounding, which is not particularly
efficient when the underlying floating point is software floating
point).
2014-11-04 Joseph Myers <joseph@codesourcery.com>
* soft-fp/op-common.h (_FP_TO_INT_ROUND): New macro.
* soft-fp/double.h [_FP_W_TYPE_SIZE < 64] (FP_TO_INT_ROUND_D): New
macro.
[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_ROUND_D): Likewise.
* soft-fp/extended.h [_FP_W_TYPE_SIZE < 64] (FP_TO_INT_ROUND_E):
New macro.
[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_ROUND_E): Likewise.
* soft-fp/quad.h [_FP_W_TYPE_SIZE < 64] (FP_TO_INT_ROUND_Q): New
macro.
[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_ROUND_Q): Likewise.
* soft-fp/single.h (FP_TO_INT_ROUND_S): New macro.
Continuing the removal of unused __libc_* function names, this patch
removes the __libc_nanosleep name.
Tested for x86_64 (testsuite, and that the disassembly of installed
shared libraries is unchanged by the patch; __nanosleep changes from
weak to strong, which is of no significance).
* posix/nanosleep.c (__libc_nanosleep): Rename to __nanosleep.
(__nanosleep): Do not define as alias.
(nanosleep): Define as alias of __nanosleep.
* sysdeps/unix/sysv/linux/syscalls.list (nanosleep): Remove
__libc_nanosleep name.
This hook can be used to perform additional compatibility checks
between shared libraries by inspecting custom program header
information.
* elf/dl-machine-reject-phdr.h: New file.
* elf/dl-load.c: #include that.
(open_verify): Call elf_machine_reject_phdr_p and ignore the file
if that returned true.
I noticed that install.texi was out of date with regard to the actual
autoconf version requirement for regenerating configure scripts. This
patch updates the documentation.
* manual/install.texi (Tools for Compilation): Update autoconf
version requirements.
* INSTALL: Regenerated.
Continuing the removal of unused __libc_* function names, this patch
removes the __libc_pselect alias.
Tested for x86_64 that installed stripped shared libraries are
unchanged by this patch.
* misc/pselect.c [!__pselect] (__libc_pselect): Remove alias.
* sysdeps/unix/sysv/linux/pselect.c [__NR_pselect6]
(__libc_pselect): Likewise.
Concluding the move of syscall definitions to syscalls.list, where the
removal of support for old kernel versions has made this possible,
this patch removes C definitions of pread, pread64, pwrite and
pwrite64 for powerpc64. As far as I can tell, the existing
syscalls.list definitions in
sysdeps/unix/sysv/linux/wordsize-64/syscalls.list should suffice to
produce results equivalent to what these C files do.
[BZ #14138]
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pread.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pwrite64.c: Likewise.
Continuing the removal of __libc_* function names that are no longer
used anywhere, this patch removes the __libc_readv and __libc_writev
names.
Tested for x86_64 that stripped installed shared libraries are
unchanged by the patch.
* include/sys/uio.h (__libc_readv): Remove declaration.
(__libc_writev): Likewise.
* misc/readv.c (__libc_readv): Rename to __readv.
(__readv): Do not define as alias.
(readv): Define as alias of __readv.
* misc/writev.c (__libc_writev): Rename to __writev.
(__writev): Do not define as alias.
(writev): Define as alias of __writev.
* sysdeps/posix/readv.c (__libc_readv): Rename to __readv.
(__readv): Do not define as alias.
(readv): Define unconditionally as alias of __readv.
* sysdeps/posix/writev.c (__libc_writev): Rename to __writev.
(__writev): Do not define as alias.
(writev): Define unconditionally as alias of __writev.
* sysdeps/unix/syscalls.list (readv): Do not define __libc_readv
name.
(writev): Do not define __libc_writev name.
glibc has lots of __libc_* function names that no longer serve any
purpose (are not used for any calls or exported at a public symbol
version). This patch removes __libc_creat. It has the effect of
creat becoming a strong symbol instead of a weak symbol in various
cases, but that's fine; in shared libraries it doesn't matter at all,
while for static linking the only other symbol sometimes defined in
the same object is creat64, and whenever creat64 is a reserved name so
is creat.
Other such cases of unnecessary __libc_* symbols are expected to be
dealt with in separate patches over time.
Tested for x86_64 (testsuite, and that the disassembly of installed
shared libraries is unchanged by the patch).
* include/fcntl.h (__libc_creat): Remove declaration.
* io/creat.c (__libc_creat): Rename to creat.
(creat): Do not define as alias.
* sysdeps/unix/sysv/linux/alpha/creat.c (creat64): Define as alias
of creat instead of __libc_creat.
* sysdeps/unix/sysv/linux/generic/creat.c (__libc_creat): Rename
to creat.
(creat): Do not define as alias.
[__WORDSIZE == 64] (creat64): Define as alias of creat instead of
__libc_creat.
* sysdeps/unix/sysv/linux/syscalls.list (creat): Do not define
__libc_creat name.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (creat):
Likewise.
Add Linux-specific comments about the atomicity of write() and
the POSIX requirements.
2014-10-29 Carlos O'Donell <carlos@redhat.com>
* manual/llio.texi: Add comments discussing why write() may be
considered MT-unsafe on Linux.
During a refactoring pass several repeated blocks of code in dl-load.c
were turned into a call to a local function named local_strdup. There
is no need for local_strdup, and the routines should instead call
__strdup. This change does just that. We call the internal symbol
__strdup because calling strdup is unsafe. The user might be
using a standard that doesn't include strdup and may have defined this
symbol in their application. During a static link we might reference
the user defined symbol and crash if it doesn't implement a standards
conforming strdup. The resulting code is simpler to understand, and
makes it easier to debug.
No regressions on x86_64.
2014-10-28 Carlos O'Donell <carlos@redhat.com>
* dl-load.c (local_strdup): Remove.
(expand_dynamic_string_token): Use __strdup.
(decompose_rpath): Likewise.
(_dl_map_object): Likewise.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch replaces its use in unwind-dw2-fde.c with hidden_def and
hidden_proto.
Tested for x86. This patch does result in code generation differences
(for some reason GCC decides to partition __register_frame_info_bases
after the patch).
[BZ #14132]
* sysdeps/generic/unwind-dw2-fde.c
(__register_frame_info_bases_internal): Do not declare.
(__register_frame_info_table_bases_internal): Likewise.
(__deregister_frame_info_bases_internal): Likewise.
(__register_frame_info_bases): Declare and use hidden_proto before
definition. Use hidden_def instead of INTDEF.
(__register_frame_info_table_bases): Likewise.
(__deregister_frame_info_bases): Likewise.
(__register_frame_info): Do not use INTUSE.
(__register_frame): Likewise.
(__register_frame_info_table): Likewise.
(__register_frame_table): Likewise.
(__deregister_frame_info): Likewise.
(__deregister_frame): Likewise.
ARM linux kernels before 3.14.3 may or may not support
futex_atomic_cmpxchg_inatomic depending on the kernel configuration (e.g.
CONFIG_CPU_USE_DOMAINS && CONFIG_SMP configuration was not supported)
Starting with 3.14.3 the linux kernel unconditionally enables support for
ARM, and this re-enables the relevant __ASSUME_* macros.
Tested on ARM both with kernels >= 3.14.3 and older kernels.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x030E03] (__ASSUME_FUTEX_LOCK_PI): Do
not undefine.
[__LINUX_KERNEL_VERSION >= 0x030E03] (__ASSUME_REQUEUE_PI):
Likewise.
[__LINUX_KERNEL_VERSION >= 0x030E03] (__ASSUME_SET_ROBUST_LIST):
Likewise.
this
will improve performance even on targets which don't have an optimized strlen. It is about twice
as
fast as the original strncat in bench-strncat.
implementation, so this improves performance even on targets which don't have an optimized
strlen and strcpy - it is 25% faster in bench-strcat. On targets which don't provide an
optimized strcat but which do have an optimized strlen and strcpy, performance gain is > 2x.
