Since memmove and memset in ld.so don't use IFUNC, don't put SSE2, AVX
and AVX512 memmove and memset in ld.so.
* sysdeps/x86_64/multiarch/memmove-avx-unaligned-erms.S: Skip
if not in libc.
* sysdeps/x86_64/multiarch/memmove-avx512-unaligned-erms.S:
Likewise.
* sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms.S:
Likewise.
* sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S:
Likewise.
__mempcpy_erms and __memmove_erms can't be placed between __memmove_chk
and __memmove it breaks __memmove_chk.
Don't check source == destination first since it is less common.
* sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S:
(__mempcpy_erms, __memmove_erms): Moved before __mempcpy_chk
with unaligned_erms.
(__memmove_erms): Skip if source == destination.
(__memmove_unaligned_erms): Don't check source == destination
first.
Intel Core i3, i5 and i7 processors have fast unaligned copy and
copy backward is ignored. Remove Fast_Copy_Backward from Intel Core
processors to avoid confusion.
* sysdeps/x86/cpu-features.c (init_cpu_features): Don't set
bit_arch_Fast_Copy_Backward for Intel Core proessors.
This patch removes the powerpc64 optimized strspn, strcspn, and
strpbrk assembly implementation now that the default C one
implements the same strategy. On internal glibc benchtests
current implementations shows similar performance with -O2.
Tested on powerpc64le (POWER8).
* sysdeps/powerpc/powerpc64/strcspn.S: Remove file.
* sysdeps/powerpc/powerpc64/strpbrk.S: Remove file.
* sysdeps/powerpc/powerpc64/strspn.S: Remove file.
With now a faster strcspn implementation, it is faster to just use
it with some return tests than reimplementing strpbrk itself.
As for strcspn optimization, it is generally at least 10 times faster
than the existing implementation on bench-strspn on a few AArch64
implementations.
Also the string/bits/string2.h inlines make no longer sense, as current
implementation will already implement most of the optimizations.
Tested on x86_64, i386, and aarch64.
* string/strpbrk.c (strpbrk): Rewrite function.
* string/bits/string2.h (strpbrk): Use __builtin_strpbrk.
(__strpbrk_c2): Likewise.
(__strpbrk_c3): Likewise.
* string/string-inlines.c
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strpbrk_c2):
Likewise.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strpbrk_c3):
Likewise.
As for strcspn, this patch improves strspn performance using a much
faster algorithm. It first constructs a 256-entry table based on
the accept string and then uses it as a lookup table for the
input string. As for strcspn optimization, it is generally at least
10 times faster than the existing implementation on bench-strspn
on a few AArch64 implementations.
Also the string/bits/string2.h inlines make no longer sense, as current
implementation will already implement most of the optimizations.
Tested on x86_64, i686, and aarch64.
* string/strspn.c (strcspn): Rewrite function.
* string/bits/string2.h (strspn): Use __builtin_strcspn.
(__strspn_c1): Remove inline function.
(__strspn_c2): Likewise.
(__strspn_c3): Likewise.
* string/string-inlines.c
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strspn_c1): Add
compatibility symbol.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strspn_c2):
Likewise.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strspn_c3):
Likewise.
Improve strcspn performance using a much faster algorithm. It is kept simple
so it works well on most targets. It is generally at least 10 times faster
than the existing implementation on bench-strcspn on a few AArch64
implementations, and for some tests 100 times as fast (repeatedly calling
strchr on a small string is extremely slow...).
In fact the string/bits/string2.h inlines make no longer sense, as GCC
already uses strlen if reject is an empty string, strchrnul is 5 times as
fast as __strcspn_c1, while __strcspn_c2 and __strcspn_c3 are slower than
the strcspn main loop for large strings (though reject length 2-4 could be
special cased in the future to gain even more performance).
Tested on x86_64, i686, and aarch64.
* string/Version (libc): Add GLIBC_2.24.
* string/strcspn.c (strcspn): Rewrite function.
* string/bits/string2.h (strcspn): Use __builtin_strcspn.
(__strcspn_c1): Remove inline function.
(__strcspn_c2): Likewise.
(__strcspn_c3): Likewise.
* string/string-inline.c
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c1): Add
compatibility symbol.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c2):
Likewise.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c3):
Likewise.
* sysdeps/i386/string-inlines.c: Include generic string-inlines.c.
This patch uses ahi instead of aghi in 32bit _dl_runtime_resolve
to adjust the stack pointer. This is no functional change,
but a cosmetic one.
ChangeLog:
* sysdeps/s390/s390-32/dl-trampoline.h (_dl_runtime_resolve):
Use ahi instead of aghi to adjust stack pointer.
When the signs differ, the precision of the conversion sometimes
drops below 106 bits. This strategy is identical to the
hexadecimal variant.
I've refactored tst-sprintf3 to enable testing a value with more
than 30 significant digits in order to demonstrate this failure
and its solution.
Additionally, this implicitly fixes a typo in the shift
quantities when subtracting from the high mantissa to compute
the difference.
Implement x86-64 memset with unaligned store and rep movsb. Support
16-byte, 32-byte and 64-byte vector register sizes. A single file
provides 2 implementations of memset, one with rep stosb and the other
without rep stosb. They share the same codes when size is between 2
times of vector register size and REP_STOSB_THRESHOLD which defaults
to 2KB.
Key features:
1. Use overlapping store to avoid branch.
2. For size <= 4 times of vector register size, fully unroll the loop.
3. For size > 4 times of vector register size, store 4 times of vector
register size at a time.
[BZ #19881]
* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
memset-sse2-unaligned-erms, memset-avx2-unaligned-erms and
memset-avx512-unaligned-erms.
* sysdeps/x86_64/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list): Test __memset_chk_sse2_unaligned,
__memset_chk_sse2_unaligned_erms, __memset_chk_avx2_unaligned,
__memset_chk_avx2_unaligned_erms, __memset_chk_avx512_unaligned,
__memset_chk_avx512_unaligned_erms, __memset_sse2_unaligned,
__memset_sse2_unaligned_erms, __memset_erms,
__memset_avx2_unaligned, __memset_avx2_unaligned_erms,
__memset_avx512_unaligned_erms and __memset_avx512_unaligned.
* sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms.S: New
file.
* sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S:
Likewise.
* sysdeps/x86_64/multiarch/memset-sse2-unaligned-erms.S:
Likewise.
* sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:
Likewise.
Implement x86-64 memmove with unaligned load/store and rep movsb.
Support 16-byte, 32-byte and 64-byte vector register sizes. When
size <= 8 times of vector register size, there is no check for
address overlap bewteen source and destination. Since overhead for
overlap check is small when size > 8 times of vector register size,
memcpy is an alias of memmove.
A single file provides 2 implementations of memmove, one with rep movsb
and the other without rep movsb. They share the same codes when size is
between 2 times of vector register size and REP_MOVSB_THRESHOLD which
is 2KB for 16-byte vector register size and scaled up by large vector
register size.
Key features:
1. Use overlapping load and store to avoid branch.
2. For size <= 8 times of vector register size, load all sources into
registers and store them together.
3. If there is no address overlap bewteen source and destination, copy
from both ends with 4 times of vector register size at a time.
4. If address of destination > address of source, backward copy 8 times
of vector register size at a time.
5. Otherwise, forward copy 8 times of vector register size at a time.
6. Use rep movsb only for forward copy. Avoid slow backward rep movsb
by fallbacking to backward copy 8 times of vector register size at a
time.
7. Skip when address of destination == address of source.
[BZ #19776]
* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
memmove-sse2-unaligned-erms, memmove-avx-unaligned-erms and
memmove-avx512-unaligned-erms.
* sysdeps/x86_64/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list): Test
__memmove_chk_avx512_unaligned_2,
__memmove_chk_avx512_unaligned_erms,
__memmove_chk_avx_unaligned_2, __memmove_chk_avx_unaligned_erms,
__memmove_chk_sse2_unaligned_2,
__memmove_chk_sse2_unaligned_erms, __memmove_avx_unaligned_2,
__memmove_avx_unaligned_erms, __memmove_avx512_unaligned_2,
__memmove_avx512_unaligned_erms, __memmove_erms,
__memmove_sse2_unaligned_2, __memmove_sse2_unaligned_erms,
__memcpy_chk_avx512_unaligned_2,
__memcpy_chk_avx512_unaligned_erms,
__memcpy_chk_avx_unaligned_2, __memcpy_chk_avx_unaligned_erms,
__memcpy_chk_sse2_unaligned_2, __memcpy_chk_sse2_unaligned_erms,
__memcpy_avx_unaligned_2, __memcpy_avx_unaligned_erms,
__memcpy_avx512_unaligned_2, __memcpy_avx512_unaligned_erms,
__memcpy_sse2_unaligned_2, __memcpy_sse2_unaligned_erms,
__memcpy_erms, __mempcpy_chk_avx512_unaligned_2,
__mempcpy_chk_avx512_unaligned_erms,
__mempcpy_chk_avx_unaligned_2, __mempcpy_chk_avx_unaligned_erms,
__mempcpy_chk_sse2_unaligned_2, __mempcpy_chk_sse2_unaligned_erms,
__mempcpy_avx512_unaligned_2, __mempcpy_avx512_unaligned_erms,
__mempcpy_avx_unaligned_2, __mempcpy_avx_unaligned_erms,
__mempcpy_sse2_unaligned_2, __mempcpy_sse2_unaligned_erms and
__mempcpy_erms.
* sysdeps/x86_64/multiarch/memmove-avx-unaligned-erms.S: New
file.
* sysdeps/x86_64/multiarch/memmove-avx512-unaligned-erms.S:
Likwise.
* sysdeps/x86_64/multiarch/memmove-sse2-unaligned-erms.S:
Likwise.
* sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S:
Likwise.
Starting with z13, vector registers can also occur as argument registers.
Thus the passed input/output register structs for
la_s390_[32|64]_gnu_plt[enter|exit] functions should reflect those new
registers. This patch extends these structs La_s390_regs and La_s390_retval
and adjusts _dl_runtime_profile() to handle those fields in case of
running on a z13 machine.
ChangeLog:
* sysdeps/s390/bits/link.h: (La_s390_vr) New typedef.
(La_s390_32_regs): Append vector register lr_v24-lr_v31.
(La_s390_64_regs): Likewise.
(La_s390_32_retval): Append vector register lrv_v24.
(La_s390_64_retval): Likeweise.
* sysdeps/s390/s390-32/dl-trampoline.h (_dl_runtime_profile):
Handle extended structs La_s390_32_regs and La_s390_32_retval.
* sysdeps/s390/s390-64/dl-trampoline.h (_dl_runtime_profile):
Handle extended structs La_s390_64_regs and La_s390_64_retval.
On s390, no fpr/vrs were saved while resolving a symbol
via _dl_runtime_resolve/_dl_runtime_profile.
According to the abi, the fpr-arguments are defined as call clobbered.
In leaf-functions, gcc 4.9 and newer can use fprs for saving/restoring gprs
instead of saving them to the stack.
If gcc do this in one of the resolver-functions, then the floating point
arguments of a library-function are invalid for the first library-function-call.
Thus, this patch saves/restores the fprs around the resolving code.
The same could occur for vector registers. Furthermore an ifunc-resolver
could also clobber the vector/floating point argument registers.
Thus this patch provides the further variants _dl_runtime_resolve_vx/
_dl_runtime_profile_vx, which are used if the kernel claims, that
we run on a machine with vector registers.
Furthermore, if _dl_runtime_profile calls _dl_call_pltexit,
the pointers to inregs-/outregs-structs were setup invalid.
Now they point to the correct location in the stack-frame.
Before branching back to the caller, the return values are now
restored instead of containing the return values of the
_dl_call_pltexit() call.
On s390-32, an endless loop occurs if _dl_call_pltexit() should be called.
Now, this code-path branches to this function instead of just after the
preceding basr-instruction.
ChangeLog:
* sysdeps/s390/s390-32/dl-trampoline.S: Include dl-trampoline.h twice
to create a non-vector/vector version for _dl_runtime_resolve and
_dl_runtime_profile. Move implementation to ...
* sysdeps/s390/s390-32/dl-trampoline.h: ... here.
(_dl_runtime_resolve) Save and restore fpr/vrs.
(_dl_runtime_profile) Save and restore vrs and fix some issues
if _dl_call_pltexit is called.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_runtime_setup):
Choose the correct resolver function if running on a machine with vx.
* sysdeps/s390/s390-64/dl-trampoline.S: Include dl-trampoline.h twice
to create a non-vector/vector version for _dl_runtime_resolve and
_dl_runtime_profile. Move implementation to ...
* sysdeps/s390/s390-64/dl-trampoline.h: ... here.
(_dl_runtime_resolve) Save and restore fpr/vrs.
(_dl_runtime_profile) Save and restore vrs and fix some issues
* sysdeps/s390/s390-64/dl-machine.h: (elf_machine_runtime_setup):
Choose the correct resolver function if running on a machine with vx.
This patch fixes the new test tst-dlsym-error build on aarch64
(and possible other architectures as well) due missing strchrnul
definition.
* elf/tst-dlsym-error.c: Include <string.h> for strchrnul.
* elf/dl-lookup.c (_dl_lookup_symbol_x): Report error even if
skip_map != NULL.
* elf/tst-dlsym-error.c: New file.
* elf/Makefile (tests): Add tst-dlsym-error.
(tst-dlsym-error): Link against libdl.
MicroBlaze has a special version of futimesat.c because it gained the
futimesat syscall later than other non-asm-generic architectures. Now
the minimum kernel is recent enough that this syscall can always be
assumed to be present for MicroBlaze, so this patch removes the
special version and the __ASSUME_FUTIMESAT macro, resulting in the
sysdeps/unix/sysv/linux/futimesat.c version being used.
Untested.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
(__ASSUME_FUTIMESAT): Remove macro.
* sysdeps/unix/sysv/linux/microblaze/futimesat.c: Remove file.
Reproducer (needs to run as root):
perl -e \
'print "large❌999:" . join(",", map {"user$_"} (1 .. 135))."\n"' \
>> /etc/group
cd /var/db
make
getent -s db group
After the fix, the last command should list the "large" group.
The magic number 135 has been chosen so that the line is shorter than
1024 bytes, but the pointers required to encode the member array will
cross the threshold, triggering the bug.
The newer Intel processors support Enhanced REP MOVSB/STOSB (ERMS) which
has a feature bit in CPUID. This patch adds the Enhanced REP MOVSB/STOSB
(ERMS) bit to x86 cpu-features.
* sysdeps/x86/cpu-features.h (bit_cpu_ERMS): New.
(index_cpu_ERMS): Likewise.
(reg_ERMS): Likewise.
<sys/personality.h> is out of sync with kernel headers, missing the
UNAME26, FDPIC_FUNCPTRS and PER_LINUX_FDPIC entries. Fix that.
Changelog:
* sysdeps/unix/sysv/linux/sys/personality.h (UNAME26, FDPIC_FUNCPTRS,
PER_LINUX_FDPIC): Add.
On AMD processors, memcpy optimized with unaligned SSE load is
slower than emcpy optimized with aligned SSSE3 while other string
functions are faster with unaligned SSE load. A feature bit,
Fast_Unaligned_Copy, is added to select memcpy optimized with
unaligned SSE load.
[BZ #19583]
* sysdeps/x86/cpu-features.c (init_cpu_features): Set
Fast_Unaligned_Copy with Fast_Unaligned_Load for Intel
processors. Set Fast_Copy_Backward for AMD Excavator
processors.
* sysdeps/x86/cpu-features.h (bit_arch_Fast_Unaligned_Copy):
New.
(index_arch_Fast_Unaligned_Copy): Likewise.
* sysdeps/x86_64/multiarch/memcpy.S (__new_memcpy): Check
Fast_Unaligned_Copy instead of Fast_Unaligned_Load.
Since commit 44d20bca52 (Implement
second fallback mode for DNS requests), there is a code path which
returns early, before *resplen2 is initialized. This happens if the
name server address is immediately recognized as invalid (because of
lack of protocol support, or if it is a broadcast address such
255.255.255.255, or another invalid address).
If this happens and *resplen2 was non-zero (which is the case if a
previous query resulted in a failure), __libc_res_nquery would reuse
an existing second answer buffer. This answer has been previously
identified as unusable (for example, it could be an NXDOMAIN
response). Due to the presence of a second answer, no name server
switching will occur. The result is a name resolution failure,
although a successful resolution would have been possible if name
servers have been switched and queries had proceeded along the search
path.
The above paragraph still simplifies the situation. Before glibc
2.23, if the second answer needed malloc, the stub resolver would
still attempt to reuse the second answer, but this is not possible
because __libc_res_nsearch has freed it, after the unsuccessful call
to __libc_res_nquerydomain, and set the buffer pointer to NULL. This
eventually leads to an assertion failure in __libc_res_nquery:
/* Make sure both hp and hp2 are defined */
assert((hp != NULL) && (hp2 != NULL));
If assertions are disabled, the consequence is a NULL pointer
dereference on the next line.
Starting with glibc 2.23, as a result of commit
e9db92d3ac (CVE-2015-7547: getaddrinfo()
stack-based buffer overflow (Bug 18665)), the second answer is always
allocated with malloc. This means that the assertion failure happens
with small responses as well because there is no buffer to reuse, as
soon as there is a name resolution failure which triggers a search for
an answer along the search path.
This commit addresses the issue by ensuring that *resplen2 is
initialized before the send_dg function returns.
This commit also addresses a bug where an invalid second reply is
incorrectly returned as a valid to the caller.
Bug 19848 reports cases where powl on x86 / x86_64 has error
accumulation, for small integer exponents, larger than permitted by
glibc's accuracy goals, at least in some rounding modes. This patch
further restricts the exponent range for which the
small-integer-exponent logic is used to limit the possible error
accumulation.
Tested for x86_64 and x86 and ulps updated accordingly.
[BZ #19848]
* sysdeps/i386/fpu/e_powl.S (p3): Rename to p2 and change value
from 8 to 4.
(__ieee754_powl): Compare integer exponent against 4 not 8.
* sysdeps/x86_64/fpu/e_powl.S (p3): Rename to p2 and change value
from 8 to 4.
(__ieee754_powl): Compare integer exponent against 4 not 8.
* math/auto-libm-test-in: Add more tests of pow.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
With the 2.6.32 minimum kernel on x86 and 3.2 on other architectures,
__NR_utimensat is always defined.
Changelog:
* sysdeps/unix/sysv/linux/futimens.c (futimens) [__NR_utimensat]:
Make code unconditional.
[!__NR_utimensat]: Remove conditional code.
* sysdeps/unix/sysv/linux/lutimes.c (lutimes) [__NR_utimensat]:
Make code unconditional.
[!__NR_utimensat]: Remove conditional code.
* sysdeps/unix/sysv/linux/utimensat.c (utimensat) [__NR_utimensat]:
Make code unconditional.
[!__NR_utimensat]: Remove conditional code.
With the 2.6.32 minimum kernel on x86 and 3.2 on other architectures,
__NR_openat is always defined.
Changelog:
* sysdeps/unix/sysv/linux/dl-openat64.c (openat64) [__NR_openat]:
Make code unconditional.
The x86-specific versions of both pthread_cond_wait and
pthread_cond_timedwait have (in their fall-back-to-futex-wait slow
paths) calls to __pthread_mutex_cond_lock_adjust followed by
__pthread_mutex_unlock_usercnt, which load the parameters before the
first call but then assume that the first parameter, in %eax, will
survive unaffected. This happens to have been true before now, but %eax
is a call-clobbered register, and this assumption is not safe: it could
change at any time, at GCC's whim, and indeed the stack-protector canary
checking code clobbers %eax while checking that the canary is
uncorrupted.
So reload %eax before calling __pthread_mutex_unlock_usercnt. (Do this
unconditionally, even when stack-protection is not in use, because it's
the right thing to do, it's a slow path, and anything else is dicing
with death.)
* sysdeps/unix/sysv/linux/i386/pthread_cond_timedwait.S: Reload
call-clobbered %eax on retry path.
* sysdeps/unix/sysv/linux/i386/pthread_cond_wait.S: Likewise.
Since only Intel processors with AVX2 have fast unaligned load, we
should set index_arch_AVX_Fast_Unaligned_Load only for Intel processors.
Move AVX, AVX2, AVX512, FMA and FMA4 detection into get_common_indeces
and call get_common_indeces for other processors.
Add CPU_FEATURES_CPU_P and CPU_FEATURES_ARCH_P to aoid loading
GLRO(dl_x86_cpu_features) in cpu-features.c.
[BZ #19583]
* sysdeps/x86/cpu-features.c (get_common_indeces): Remove
inline. Check family before setting family, model and
extended_model. Set AVX, AVX2, AVX512, FMA and FMA4 usable
bits here.
(init_cpu_features): Replace HAS_CPU_FEATURE and
HAS_ARCH_FEATURE with CPU_FEATURES_CPU_P and
CPU_FEATURES_ARCH_P. Set index_arch_AVX_Fast_Unaligned_Load
for Intel processors with usable AVX2. Call get_common_indeces
for other processors with family == NULL.
* sysdeps/x86/cpu-features.h (CPU_FEATURES_CPU_P): New macro.
(CPU_FEATURES_ARCH_P): Likewise.
(HAS_CPU_FEATURE): Use CPU_FEATURES_CPU_P.
(HAS_ARCH_FEATURE): Use CPU_FEATURES_ARCH_P.
* malloc/Makefile ($(objpfx)tst-malloc-backtrace,
$(objpfx)tst-malloc-thread-exit, $(objpfx)tst-malloc-thread-fail): Use
$(shared-thread-library) instead of hardcoding the path to libpthread.
This patch removes the __ASSUME_GETDENTS64_SYSCALL macro, as its
definition is constant given the new kernel version requirements (and
was constant anyway before those requirements except for MIPS n32).
Note that the "#ifdef __NR_getdents64" conditional *is* still needed,
because MIPS n64 only has the getdents syscall (being a 64-bit ABI,
that syscall is 64-bit; the difference between the two on 64-bit
architectures is where d_type goes). If MIPS n64 were to gain the
getdents64 syscall and we wanted to use it conditionally on the kernel
version at runtime we'd have to revert this patch, but I think that's
unlikely (and in any case, we could follow the simpler approach of
undefining __NR_getdents64 if the syscall can't be assumed, just like
we do for accept4 / recvmmsg / sendmmsg syscalls on architectures
where socketcall support came first).
Most of the getdents.c changes are reindentation.
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h
(__ASSUME_GETDENTS64_SYSCALL): Remove macro.
* sysdeps/unix/sysv/linux/getdents.c
[!__ASSUME_GETDENTS64_SYSCALL]: Remove conditional code.
[!have_no_getdents64_defined]: Likewise.
(__GETDENTS): Remove __have_no_getdents64 conditional.
Current Linux kernel version requirements mean the signalfd4 syscall
can always be assumed to be available. This patch removes
__ASSUME_SIGNALFD4 and associated conditionals.
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_SIGNALFD4):
Remove macro.
* sysdeps/unix/sysv/linux/signalfd.c: Do not include
<kernel-features.h>.
(signalfd) [__NR_signalfd4]: Make code unconditional.
(signalfd) [!__ASSUME_SIGNALFD4]: Remove conditional code.
This patch fixes the implicit check style add in 2a69f853c for the
general convention one.
Checked on x86_64.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Fix implict checks
style.
When PLT may be used, JUMPTARGET should be used instead calling the
function directly.
* sysdeps/unix/sysv/linux/x86_64/cancellation.S
(__pthread_enable_asynccancel): Use JUMPTARGET to call
__pthread_unwind.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
(__condvar_cleanup2): Use JUMPTARGET to call _Unwind_Resume.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S
(__condvar_cleanup1): Likewise.
When installing glibc (w/mathvec enabled) in-place on a system with
a glibc w/out mathvec enabled, the install will clobber the existing
libm.so (e.g., /lib64/libm-2.21.so) with a linker script. This is
because libm.so is a symlink to libm.so.6 which is a symlink to the
final libm-2.21.so file. When the makefile writes the linker script
directly to libm.so, it gets clobbered.
The simple patch below to math/Makefile fixes this. It is based on
the nptl Makefile, which does exactly the same thing in a safer way.
Current Linux posix_spawn spawn do not test if the pid argument is
valid before trying to update it for success case. This patch fixes
it.
Tested on x86_64 and i686.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Fix invalid memory
access where posix_spawn success and pid argument is null.
* posix/tst-spawn.c (do_test): Add posix_spawn null pid argument for
success case.
* sysdeps/generic/dl-fcntl.h: New file, adds attribute_hidden to __open
and __fcntl.
* sysdeps/mach/hurd/dl-fcntl.h: New file, adds attribute_hidden to
__fcntl only.
* include/fcntl.h [IS_IN (rtld)]: Include <dl-fcntl.h> instead of
adding attribute_hidden to __open and __fcntl.
Generating errnos.d does not actually need libc-modules.h.
* sysdeps/mach/hurd/Makefile ($(common-objpfx)errnos.d): Strip
"-include $(common-objpfx)libc-modules.h" from CPPFLAGS, and do not
depend on libc-modules.h,
Given current Linux kernel version requirements, we can assume the
presence of the eventfd2 syscall. This means that __ASSUME_EVENTFD2
can be removed, and a syscalls.list entry suffices for eventfd instead
of needing a .c file. This patch implements those changes.
Tested for x86_64 and x86 (not that that means much, given the lack of
testsuite coverage for eventfd).
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_EVENTFD2):
Remove macro.
* sysdeps/unix/sysv/linux/eventfd.c: Remove file.
* sysdeps/unix/sysv/linux/syscalls.list (eventfd): New syscall
entry.
Given current Linux kernel version requirements, we can always assume
the fallocate syscall to be available. This patch removes
__ASSUME_FALLOCATE and a test for whether __NR_fallocate is defined.
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_FALLOCATE):
Remove macro.
* sysdeps/unix/sysv/linux/wordsize-64/posix_fallocate.c: Do not
include <kernel-features.h>.
[!__ASSUME_FALLOCATE]: Remove conditional code.
(posix_fallocate) [__NR_fallocate]: Make code unconditional.
When building on i686, x86_64, and arm, and with NDEBUG, or --with-cpu
there are various variables and functions which are unused based on
these settings.
This patch marks all such variables with __attribute__((unused)) to
avoid the compiler warnings when building with the aformentioned
options.
With current kernel version requirements, the ppoll Linux syscall can
be assumed to be present on all architectures; this patch removes the
__ASSUME_PPOLL macro and conditionals on it and on whether __NR_ppoll
is defined. (Note that the same can't yet be done for pselect,
because MicroBlaze only wired that up in the syscall table in 3.15.)
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_PPOLL):
Remove macro.
* sysdeps/unix/sysv/linux/ppoll.c: Do not include
<kernel-features.h>.
[__NR_ppoll]: Make code unconditional.
[!__ASSUME_PPOLL]: Remove conditional code.
This patch adjusts the defaults for kernel-features.h macros relating
to availability of accept4, recvmmsg and sendmmsg. It is not intended
to affect which macros end up getting defined in any configuration.
At present, all architectures with syscalls for those functions need
to define __ASSUME_*_SYSCALL macros; in particular, any new
architecture needs its own kernel-features.h file for that purpose,
though it may not otherwise need such a header. Those macros are then
used together with __ASSUME_SOCKETCALL to define macros for whether
the functions in question are available.
This patch changes the defaults so that the syscalls are assumed to be
available by default with recent-enough kernels, and it is the
responsibility of architecture headers to undefine the macros if they
are unavailable in supported kernels at least as recent as the version
where the architecture-independent functionality was introduced. The
__ASSUME_<function> macros are defaulted similarly instead of being
defined based on other macros (defining based on other macros would no
longer work because the #undefs appear after the generic header is
included), so where the syscall being unavailable means the function
is unavailable this means the architecture header has to undefine the
__ASSUME_<function> macro; this only affects __ASSUME_ACCEPT4 for
ia64, as other cases where the syscalls were added late enough to be
relevant with current kernel version requirements are all on
socketcall architectures.
As a consequence, the AArch64 and Nios II kernel-features.h header
files are removed, and others simplified. When the minimum kernel
version becomes 4.3 or later on all architectures, the syscalls in
question can just be assumed unconditionally, permitting further
simplification.
Tested for x86_64, x86 and powerpc (that installed shared libraries
are unchanged by the patch, and testsuite for x86_64 and x86).
* sysdeps/unix/sysv/linux/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Define unconditionally.
(__ASSUME_ACCEPT4): Likewise.
[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
Define.
[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG):
Likewise.
[__LINUX_KERNEL_VERSION >= 0x030000] (__ASSUME_SENDMMSG_SYSCALL):
Likewise.
[__LINUX_KERNEL_VERSION >= 0x030000] (__ASSUME_SENDMMSG):
Likewise.
* sysdeps/unix/sysv/linux/aarch64/kernel-features.h: Remove file.
* sysdeps/unix/sysv/linux/nios2/kernel-features.h: Likewise.
* sysdeps/unix/sysv/linux/alpha/kernel-features.h
(__ASSUME_RECVMMSG_SYSCALL): Do not define.
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/hppa/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/i386/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
Likewise.
[__LINUX_KERNEL_VERSION >= 0x030000] (__ASSUME_SENDMMSG_SYSCALL):
Likewise.
(__ASSUME_ACCEPT4_SYSCALL): Undefine if [__LINUX_KERNEL_VERSION <
0x040300] instead of defining if [__LINUX_KERNEL_VERSION >=
0x040300].
* sysdeps/unix/sysv/linux/ia64/kernel-features.h
(__ASSUME_RECVMMSG_SYSCALL): Do not define.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
(__ASSUME_ACCEPT4_SYSCALL): Undefine if [__LINUX_KERNEL_VERSION <
0x030300] instead of defining if [__LINUX_KERNEL_VERSION >=
0x030300].
[__LINUX_KERNEL_VERSION < 0x030300] (__ASSUME_ACCEPT4): Undefine.
* sysdeps/unix/sysv/linux/m68k/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Undefine if [__LINUX_KERNEL_VERSION <
0x040300] instead of defining if [__LINUX_KERNEL_VERSION >=
0x040300].
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Do not define.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Undefine if [__LINUX_KERNEL_VERSION <
0x030300] instead of defining if [__LINUX_KERNEL_VERSION >=
0x030300].
* sysdeps/unix/sysv/linux/mips/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Do not define.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/powerpc/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/s390/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Undefine if [__LINUX_KERNEL_VERSION <
0x040300] instead of defining if [__LINUX_KERNEL_VERSION >=
0x040300].
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/sh/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Do not define.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/sparc/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/tile/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_RECVMMSG_SYSCALL): Likewise.
(__ASSUME_SENDMMSG_SYSCALL): Likewise.
* sysdeps/unix/sysv/linux/x86_64/kernel-features.h
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
Likewise.
[__LINUX_KERNEL_VERSION >= 0x030000] (__ASSUME_SENDMMSG_SYSCALL):
Likewise.
The number of currently defined nameservers is stored in ->nscount,
whereas ->_u._ext.nscount is set by __libc_res_nsend only after local
initializations.
This patch updates the glibc headers with the defines MADV_FREE,
IPV6_HDRINCL and EPOLLEXCLUSIVE that are added in Linux 4.5.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* bits/mman-linux.h [__USE_MISC] (MADV_FREE): New macro.
* sysdeps/unix/sysv/linux/hppa/bits/mman.h [__USE_MISC]
(MADV_FREE): Likewise.
* sysdeps/unix/sysv/linux/bits/in.h (IPV6_HDRINCL): Likewise.
* sysdeps/unix/sysv/linux/sys/epoll.h (enum EPOLL_EVENTS): Add
EPOLLEXCLUSIVE.
A large number of the test-ldouble failures seen for ldbl-128ibm are
spurious "underflow" and "inexact" exceptions. These arise from such
exceptions in the underlying arithmetic; unlike other spurious
exceptions from that arithmetic, they do not in general relate to
cases where the returned result is also substantially inaccurate, are
not so readily avoidable by appropriately conditional libgcc patches,
and are widespread enough to be hard to handle through individual
XFAILing of the affected tests.
Thus, this patch documents relaxed accuracy goals for libm functions
for IBM long double and makes libm-test.inc reflect these spurious
exceptions in ldbl-128ibm arithmetic and always allow them in
ldbl-128ibm testing (while still not allowing these exceptions to be
missing where required to be present). Tested for powerpc.
* manual/math.texi (Errors in Math Functions): Document relaxed
accuracy goals for IBM long double.
* math/libm-test.inc (test_exceptions): Always allow spurious
"underflow" and "inexact" exceptions for IBM long double.
index_* and bit_* macros are used to access cpuid and feature arrays o
struct cpu_features. It is very easy to use bits and indices of cpuid
array on feature array, especially in assembly codes. For example,
sysdeps/i386/i686/multiarch/bcopy.S has
HAS_CPU_FEATURE (Fast_Rep_String)
which should be
HAS_ARCH_FEATURE (Fast_Rep_String)
We change index_* and bit_* to index_cpu_*/index_arch_* and
bit_cpu_*/bit_arch_* so that we can catch such error at build time.
[BZ #19762]
* sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h
(EXTRA_LD_ENVVARS): Add _arch_ to index_*/bit_*.
* sysdeps/x86/cpu-features.c (init_cpu_features): Likewise.
* sysdeps/x86/cpu-features.h (bit_*): Renamed to ...
(bit_arch_*): This for feature array.
(bit_*): Renamed to ...
(bit_cpu_*): This for cpu array.
(index_*): Renamed to ...
(index_arch_*): This for feature array.
(index_*): Renamed to ...
(index_cpu_*): This for cpu array.
[__ASSEMBLER__] (HAS_FEATURE): Add and use field.
[__ASSEMBLER__] (HAS_CPU_FEATURE)): Pass cpu to HAS_FEATURE.
[__ASSEMBLER__] (HAS_ARCH_FEATURE)): Pass arch to HAS_FEATURE.
[!__ASSEMBLER__] (HAS_CPU_FEATURE): Replace index_##name and
bit_##name with index_cpu_##name and bit_cpu_##name.
[!__ASSEMBLER__] (HAS_ARCH_FEATURE): Replace index_##name and
bit_##name with index_arch_##name and bit_arch_##name.
In makecontext the FDE needs to be terminated before the return
trampoline otherwise backtrace called within a context created by
makecontext yields infinite backtrace.
This bug has been present for a long time, stdlib/tst-makecontext did
not fail until recent commit e535ce25. Tested on mips-linux-gnu and
mips64el-linux-gnuabi64 and mips-linux-gnu, no regression.
This fixes stdlib/tst-makecontext on MIPS.
Changelog:
[BZ #19792]
* sysdeps/unix/sysv/linux/mips/makecontext.S (__makecontext):
Terminate FDE before return label.
The ldbl-128ibm implementation of nearbyintl uses logic that only
works in round-to-nearest mode. This contrasts with rintl, which
works in all rounding modes.
Now, arguably nearbyintl could simply be aliased to rintl, given that
spurious "inexact" is generally allowed for ldbl-128ibm, even for the
underlying arithmetic operations. But given that the only point of
nearbyintl is to avoid "inexact", this patch follows the more
conservative approach of adding conditionals to the rintl
implementation to make it suitable for use to implement nearbyintl,
then builds it for nearbyintl with USE_AS_NEARBYINTL defined. The
test test-nearbyint-except-2 shows up issues when traps on "inexact"
are enabled, which turn out to be problems with the powerpc
fenv_private.h implementation (two functions that should disable
exception traps potentially failing to do so in some cases); this
patch duly fixes that as well (I don't see any other existing cases
where this would be user-visible; there isn't much use of *_NOEX,
*hold* etc. in libm that requires exceptions to be discarded and not
trapped on).
Tested for powerpc.
[BZ #19790]
* sysdeps/ieee754/ldbl-128ibm/s_rintl.c [USE_AS_NEARBYINTL]
(rintl): Define as macro.
[USE_AS_NEARBYINTL] (__rintl): Likewise.
(__rintl) [USE_AS_NEARBYINTL]: Use SET_RESTORE_ROUND_NOEX instead
of fesetround. Ensure results are evaluated before end of scope.
* sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: Define
USE_AS_NEARBYINTL and include s_rintl.c.
* sysdeps/powerpc/fpu/fenv_private.h (libc_feholdsetround_ppc):
Disable exception traps in new environment.
(libc_feholdsetround_ppc_ctx): Likewise.
The GNU libc testsuite fails to build on powerpc/ppc64/ppc64le with the
following error:
../sysdeps/powerpc/test-get_hwcap.c:26:22: fatal error: sys/auxv.h: No such file or director
This is because test-get_hwcap.c includes <sys/auxv.h>, but we don't
provide a wrapper in include/sys. This patch adds one.
Changelog:
* include/sys/auxv.h: New file.
Since x86 has an optimized mempcpy and GCC can inline mempcpy on x86,
define _HAVE_STRING_ARCH_mempcpy to 1 for x86.
[BZ #19759]
* sysdeps/x86/bits/string.h (_HAVE_STRING_ARCH_mempcpy): New.
The operand modifier %s on powerpc is an undocumented internal implementation
detail of GCC. Besides that, the GCC community wants to remove it. This patch
rewrites the expressions that use this modifier with logically equivalent
expressions that don't require it.
Explanation for the substitution:
The %s modifier takes an immediate operand and prints 32 less such immediate.
Thus, in the previous code, the expression resulted in:
32 - __builtin_ffs(e)
where e was guaranteed to have exactly a single bit set, by the following
expressions:
(e & (e-1) == 0) : e has at most one bit set.
(e != 0) : e is not zero, thus it has at least one bit set.
Since we guarantee that there is exactly only one bit set, the following
statement is true:
32 - __builtin_ffs(e) == __builtin_clz(e)
Thus, we can replace __builtin_ffs with __builtin_clz and remove the %s operand
modifier.
HWCAP-related code should had been updated when the 32 bits of HWCAP were
used. This patch updates the code in dl-procinfo.h to loop through all
the 32 bits in HWCAP and updates _dl_powerpc_cap_flags accordingly.
benchtests should use $(test-via-rtld-prefix) and $(+link-tests) like
other glibc tests.
[BZ #19783]
* benchtests/Makefile (run-bench): Replace $(rtld-prefix) with
$(test-via-rtld-prefix).
($(binaries-bench)): Replace $(+link) with $(+link-tests).
This patch fixes the posix/tst-execvpe5 invocation when GLIBC is
configured with --enable-hardcoded-path-in-tests which fails with:
$ cat posix/tst-execvpe5.out
Wrong number of arguments (4)
Checked on x86-64 and powerpc64le.
* posix/tst-execvpe5.c (do_test): Fix fix test invocation when
configured with --enable-hardcoded-path-in-tests.
The ldbl-128ibm implementation of remainderl has logic resulting in
incorrect tests for equality of the absolute values of the arguments
in the case of zero low parts. If the low parts are both zero but
with different signs, this can wrongly cause equal arguments to be
treated as different, resulting in turn in incorrect signs of zero
result in nondefault rounding modes arising from the subtractions done
when the arguments are not equal.
This patch fixes the logic to convert -0 low parts into +0 before the
comparison (remquo already has separate logic to deal with signs of
zero results, so doesn't need such a change). Tests are added for
remainderl and remquol similar to that for fmodl, and based on a
refactoring of it, since the bug depends on low parts which should not
be relied upon in tests not setting the representation explicitly
(although in fact the bug shows up in test-ldouble with current GCC).
Tested for powerpc.
[BZ #19677]
* sysdeps/ieee754/ldbl-128ibm/e_remainderl.c
(__ieee754_remainderl): Put zero low parts in canonical form.
* sysdeps/ieee754/ldbl-128ibm/test-fmodrem-ldbl-128ibm.c: New
file. Based on
sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c.
* sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c: Replace
with wrapper round test-fmodrem-ldbl-128ibm.c.
* sysdeps/ieee754/ldbl-128ibm/test-remainderl-ldbl-128ibm.c: New
file.
* sysdeps/ieee754/ldbl-128ibm/test-remquol-ldbl-128ibm.c:
Likewise.
* sysdeps/ieee754/ldbl-128ibm/Makefile (tests): Add
test-remainderl-ldbl-128ibm and test-remquol-ldbl-128ibm.
When using sln on some filesystems which return 64-bit inodes,
the stat call might fail during install like so:
.../elf/sln .../elf/symlink.list
/lib32/libc.so.6: invalid destination: Value too large for defined data type
/lib32/ld-linux.so.2: invalid destination: Value too large for defined data type
Makefile:104: recipe for target 'install-symbolic-link' failed
Switch to using stat64 all the time to avoid this.
URL: https://bugs.gentoo.org/576396
With older kernels, it is mostly ineffective because it causes malloc
to switch from sbrk to mmap (potentially invalidating malloc testing
compared to what real appliations do). With newer kernels which
have switched to enforcing RLIMIT_DATA for mmap as well, some test
cases will fail in an unintended fashion because the limit which was
set previously does not include room for all mmap mappings.
This patch implements a new posix_spawn{p} implementation for Linux. The main
difference is it uses the clone syscall directly with CLONE_VM and CLONE_VFORK
flags and a direct allocated stack. The new stack and start function solves
most the vfork limitation (possible parent clobber due stack spilling). The
remaning issue are related to signal handling:
1. That no signal handlers must run in child context, to avoid corrupt
parent's state.
2. Child must synchronize with parent to enforce stack deallocation and
to possible return execv issues.
The first one is solved by blocking all signals in child, even NPTL-internal
ones (SIGCANCEL and SIGSETXID). The second issue is done by a stack allocation
in parent and a synchronization with using a pipe or waitpid (in case or error).
The pipe has the advantage of allowing the child signal an exec error (checked
with new tst-spawn2 test).
There is an inherent race condition in pipe2 usage for architectures that do not
support the syscall directly. In such cases the a pipe plus fctnl is used
instead and it may lead to file descriptor leak in parent (as decribed by fcntl
documentation).
The child process stack is allocate with a mmap with MAP_STACK flag using
default architecture stack size. Although it is slower than use a stack buffer
from parent, it allows some slack for the compatibility code to run scripts
with no shebang (which may use a buffer with size depending of argument list
count).
Performance should be similar to the vfork default posix implementation and
way faster than fork path (vfork on mostly linux ports are basically
clone with CLONE_VM plus CLONE_VFORK). The only difference is the syscalls
required for the stack allocation/deallocation.
It fixes BZ#10354, BZ#14750, and BZ#18433.
Tested on i386, x86_64, powerpc64le, and aarch64.
[BZ #14750]
[BZ #10354]
[BZ #18433]
* include/sched.h (__clone): Add hidden prototype.
(__clone2): Likewise.
* include/unistd.h (__dup): Likewise.
* posix/Makefile (tests): Add tst-spawn2.
* posix/tst-spawn2.c: New file.
* sysdeps/posix/dup.c (__dup): Add hidden definition.
* sysdeps/unix/sysv/linux/aarch64/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/alpha/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/arm/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/hppa/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/i386/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/ia64/clone2.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/m68k/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/microblaze/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/mips/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/nios2/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S (__clone):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S (__clone):
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/sh/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/tile/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/x86_64/clone.S (__clone): Likewise.
* sysdeps/unix/sysv/linux/nptl-signals.h
(____nptl_is_internal_signal): New function.
* sysdeps/unix/sysv/linux/spawni.c: New file.
This patch removes all the dynamic allocation on execvpe code and
instead use direct stack allocation. This is QoI approach to make
it possible use in scenarios where memory is shared with parent
(vfork or clone with CLONE_VM).
For default process spawn (script file without a shebang), stack
allocation is bounded by NAME_MAX plus PATH_MAX plus 1. Large
file arguments returns an error (ENAMETOOLONG). This differs than
current GLIBC pratice in general, but it used to limit stack
allocation for large inputs. Also, path in PATH environment variable
larger than PATH_MAX are ignored.
The shell direct execution exeception, where execve returns ENOEXEC,
might requires a large stack allocation due large input argument list.
Tested on i686, x86_64, powerpc64le, and aarch64.
* posix/execvpe.c (__execvpe): Remove dynamic allocation.
* posix/Makefile (tests): Add tst-execvpe{1,2,3,4,5,6}.
* posix/tst-execvp1.c (do_test): Use a macro to call execvp.
* posix/tst-execvp2.c (do_test): Likewise.
* posix/tst-execvp3.c (do_test): Likewise.
* posix/tst-execvp4.c (do_test): Likewise.
* posix/tst-execvpe1.c: New file.
* posix/tst-execvpe2.c: Likewise.
* posix/tst-execvpe3.c: Likewise.
* posix/tst-execvpe4.c: Likewise.
* posix/tst-execvpe5.c: Likewise.
* posix/tst-execvpe6.c: Likewise.
GLIBC execl{e,p} implementation might use malloc if the total number of
arguments exceed initial assumption size (1024). This might lead to
issues in two situations:
1. execl/execle is stated to be async-signal-safe by POSIX [1]. However
if execl is used in a signal handler with a large argument set (that
may call malloc internally) and if the resulting call fails it might
lead malloc in the program in a bad state.
2. If the functions are used in a vfork/clone(VFORK) situation it also
might issue malloc internal bad state.
This patch fixes it by using stack allocation instead. It also fixes
BZ#19534.
Tested on x86_64.
[1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html
[BZ #19534]
* posix/execl.c (execl): Remove dynamic memory allocation.
* posix/execle.c (execle): Likewise.
* posix/execlp.c (execlp): Likewise.
Since we have loaded address of PREINIT_FUNCTION into %rax, we can
avoid extra branch to PLT slot.
[BZ #19745]
* sysdeps/x86_64/crti.S (_init): Replace PREINIT_FUNCTION@PLT
with *%rax in call.
Since __libc_start_main is called very early, lazy binding isn't relevant
here. Use indirect branch via GOT to avoid extra branch to PLT slot.
[BZ #19745]
* sysdeps/x86_64/start.S (_start): __libc_start_main@PLT
with *__libc_start_main@GOTPCREL(%rip) in call.
Chek Fast_Unaligned_Load, instead of Slow_BSF, and also check for
Fast_Copy_Backward to enable __memcpy_ssse3_back. Existing selection
order is updated with following selection order:
1. __memcpy_avx_unaligned if AVX_Fast_Unaligned_Load bit is set.
2. __memcpy_sse2_unaligned if Fast_Unaligned_Load bit is set.
3. __memcpy_sse2 if SSSE3 isn't available.
4. __memcpy_ssse3_back if Fast_Copy_Backward bit it set.
5. __memcpy_ssse3
[BZ #18880]
* sysdeps/x86_64/multiarch/memcpy.S: Check Fast_Unaligned_Load,
instead of Slow_BSF, and also check for Fast_Copy_Backward to
enable __memcpy_ssse3_back.
