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Adhemerval Zanella 9ff72da471 posix: New Linux posix_spawn{p} implementation
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.
2016-03-07 11:53:47 +07:00
argp argp: Use fwrite_unlocked instead of __fxprintf when !_LIBC 2016-01-07 04:25:54 -05:00
assert Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
benchtests Use $(PYTHON) to run benchtests python files. 2016-01-13 11:00:57 -05:00
bits Add _STRING_INLINE_unaligned and string_private.h 2016-02-18 14:55:29 -02:00
catgets Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
conf (NEED_INETADDR, NEED_INETATON): Define to 1, not empty. 1995-09-08 20:24:57 +00:00
conform Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
crypt Fix build failures with -DDEBUG. 2016-01-15 11:07:41 -07:00
csu Update copyright dates not handled by scripts/update-copyrights. 2016-01-04 16:26:30 +00:00
ctype Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
debug Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
dirent Deprecate readdir_r, readdir64_r [BZ #19056] 2016-02-20 12:56:55 +01:00
dlfcn Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
elf Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
gmon Copy x86_64 _mcount.op from _mcount.o 2016-03-03 06:56:22 -08:00
gnulib Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
grp Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
gshadow Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
hesiod Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
hurd Fix O_DIRECTORY lookup on trivial translators 2016-01-13 00:48:30 +01:00
iconv Fix build failures with -DDEBUG. 2016-01-15 11:07:41 -07:00
iconvdata S390: Fix build error in iconvdata/bug-iconv11.c. 2016-01-20 08:32:37 +01:00
include posix: New Linux posix_spawn{p} implementation 2016-03-07 11:53:47 +07:00
inet Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
intl Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
io Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
libidn Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
libio Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
locale Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
localedata localedata: clear LC_IDENTIFICATION tel/fax fields 2016-03-05 11:53:23 -05:00
login Update copyright dates not handled by scripts/update-copyrights. 2016-01-04 16:26:30 +00:00
mach Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
malloc malloc: Remove NO_THREADS 2016-02-19 17:07:45 +01:00
manual Require Linux 3.2 except on x86 / x86_64, 3.2 headers everywhere. 2016-02-24 17:15:12 +00:00
math Omit test-math-isinff when no C++ compiler. 2016-03-04 13:27:25 -08:00
mathvec Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
misc hsearch_r: Apply VM size limit in test case 2016-02-12 12:57:40 +01:00
nis Silence some false positive warnings for gcc 4.7 2016-01-21 09:11:17 -05:00
nptl nptl: support thread stacks that grow up 2016-02-19 12:41:29 -05:00
nptl_db Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
nscd Fix build errors with -DNDEBUG. 2016-01-15 10:44:07 -07:00
nss Update copyright dates not handled by scripts/update-copyrights. 2016-01-04 16:26:30 +00:00
po Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
posix posix: New Linux posix_spawn{p} implementation 2016-03-07 11:53:47 +07:00
pwd Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
resolv res_ninit: Update comment 2016-02-19 17:00:47 +01:00
resource Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
rt Fix race in tst-mqueue5 2016-01-15 16:53:08 -02:00
scripts Make shebang interpreter directives consistent 2016-01-08 14:09:06 -05:00
setjmp Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
shadow Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
signal Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
socket Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
soft-fp Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
stdio-common Silence some false positive warnings for gcc 4.7 2016-01-21 09:11:17 -05:00
stdlib [ARM] add missing -funwind-tables to test case (bug 19529) 2016-02-11 17:27:20 +00:00
streams Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
string Add _STRING_INLINE_unaligned and string_private.h 2016-02-18 14:55:29 -02:00
sunrpc Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
sysdeps posix: New Linux posix_spawn{p} implementation 2016-03-07 11:53:47 +07:00
sysvipc Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
termios Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
time Fix build failures with -DDEBUG. 2016-01-15 11:07:41 -07:00
timezone Force rereading TZDEFRULES after it was used to set DST rules only (bug #19253) 2016-01-11 16:42:25 +01:00
wcsmbs Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
wctype Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
.gitattributes exempt timezone files from the no-bad-whitespace policy 2009-06-15 18:15:54 +02:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Add arm-nacl port. 2015-04-17 09:02:19 -07:00
aclocal.m4 Rename localedir to complocaledir (bug 14259). 2015-11-27 10:22:38 -05:00
BUGS [BZ #5222] 2007-10-28 08:24:07 +00:00
ChangeLog posix: New Linux posix_spawn{p} implementation 2016-03-07 11:53:47 +07:00
ChangeLog.1 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.2 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.3 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.4 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.5 * sysdeps/posix/getaddrinfo.c: Implement configuration file 2006-05-04 06:38:07 +00:00
ChangeLog.6 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.7 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.8 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.9 Update. 2000-04-28 06:14:43 +00:00
ChangeLog.10 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.11 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.12 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.13 Update. 2002-10-03 16:37:04 +00:00
ChangeLog.14 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.15 Split out ChangeLog.15 at 2.3 branch point 2005-02-16 07:34:17 +00:00
ChangeLog.16 Fix typo in name 2012-06-21 16:45:27 +02:00
ChangeLog.17 Revert "Sun agreed to a change of the license for the RPC code to a BSD-like license." 2010-06-27 19:34:03 -07:00
ChangeLog.old-ports Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aarch64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aix Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-alpha Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-am33 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-arm Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-cris Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-hppa Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-ia64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-linux-generic Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-m68k Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-microblaze Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-mips Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-powerpc Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-tile Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
config.h.in Remove linux/fanotify.h configure test. 2016-02-24 18:44:10 +00:00
config.make.in Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
configure Regenerated configure scripts. 2016-02-18 18:36:10 -02:00
configure.ac configure: make the unsupported error message less hostile 2016-01-17 15:24:54 -05:00
CONFORMANCE Move __STDC_* predefined macros from features.h to stdc-predef.h. 2012-02-22 12:53:04 +00:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
cppflags-iterator.mk 2004-03-11 Jeroen Dekkers <jeroen@dekkers.cx> 2004-03-14 19:13:17 +00:00
extra-lib.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
extra-modules.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Require Linux 3.2 except on x86 / x86_64, 3.2 headers everywhere. 2016-02-24 17:15:12 +00:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
Makeconfig Enable --localedir to set message catalog directory (Bug 14259) 2016-02-24 20:06:04 -05:00
Makefile Fix edito in last change. 2016-03-04 15:45:35 -08:00
Makefile.in Remove redundant C locale settings. 2014-06-07 19:58:36 +00:00
Makerules Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
NAMESPACE Add and update many more entries. 2000-03-20 00:42:58 +00:00
NEWS NEWS (2.23): Fix typo in bug 19048 text. 2016-02-24 22:04:13 -05:00
o-iterator.mk Fri Mar 17 12:58:37 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu> 1995-03-17 18:42:51 +00:00
PROJECTS Update. 2004-10-12 06:19:23 +00:00
README Require Linux 3.2 except on x86 / x86_64, 3.2 headers everywhere. 2016-02-24 17:15:12 +00:00
Rules Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
shlib-versions This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
test-skeleton.c test-skeleton: increase default TIMEOUT to 20 seconds 2016-02-19 13:48:56 -05:00
version.h Open development for 2.24. 2016-02-18 16:11:58 -02:00
WUR-REPORT * posix/unistd.h (setuid, setreuid, seteuid, setresuid): 2012-08-01 18:12:58 +02:00

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