The symbol was moved using scripts/move-symbol-to-libc.py.
__pthread_mutex_lock@GLIBC_2.34 is not removed in this commit
because it is still used from nptl/nptl-init.c.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The calls to __pthread_mutex_init, __pthread_mutexattr_init,
__pthread_mutexattr_settype are now private and no longer need
to be exported. This allows the removal of the newly added
GLIBC_2.34 symbol versions for those functions.
Also clean up some weak declarations in <libc-lockP.h> for
these functions. They are not needed and potentially incorrect
for static linking of mtx_init.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_mutex_destroy@@GLIBC_2.34 symbol is no longer
neded because this commit makes __pthread_mutex_destroy@GLIBC_2.0
a compatibility symbol, so remove the new symbol version.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_cond_wait@@GLIBC_PRIVATE symbol is no longer
neded, so remove that as well.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_cond_timedwait@@GLIBC_PRIVATE symbol is no longer
neded, so remove that as well.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_cond_signal@@GLIBC_PRIVATE symbol is no longer
neded, so remove that as well.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_cond_init@@GLIBC_PRIVATE symbol is no longer
neded, so remove that as well.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_cond_destroy@@GLIBC_PRIVATE symbol is no longer
neded, so remove that as well.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
The __pthread_cond_broadcast@@GLIBC_PRIVATE symbol is no longer
neded, so remove that as well.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The symbol was moved using scripts/move-symbol-to-libc.py.
This change also turns __pthread_once into a compatibility symbol
because after the call_once move, an internal call to __pthread_once
can be used. This an adjustment to __libc_once: Outside libc (e.g.,
in nscd), it has to call pthread_once. With __pthread_once as a
compatibility symbol, it is no longer to add a new GLIBC_2.34
version after the move from libpthread, and this commit removes
the new __pthread_once@@GLIBC_2.34 version.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
GCC 11 warns when a pointer to an uninitialized object is passed
to a function that takes a const-qualified argument. This is done
on the assumption that most such functions read from the object.
For the rare case of a function that doesn't, GCC 11 extends
attribute access to add a new mode called none.
POSIX pthread_setspecific() is one such rare function that takes
a const void* argument but that doesn't read from the object it
points to. To suppress the -Wmaybe-uninitialized issued by GCC
11 when the address of an uninitialized object is passed to it
(e.g., the result of malloc()), this change #defines
__attr_access_none in cdefs.h and uses the macro on the function
in sysdeps/htl/pthread.h and sysdeps/nptl/pthread.h.
For some architectures, the two functions are aliased, so these
symbols need to be moved at the same time.
The symbols were moved using scripts/move-symbol-to-libc.py.
And pthread_mutexattr_setkind_np as a compatibility symbol.
__pthread_mutexattr_settype is used in mtx_init from libpthread,
so this commit adds a GLIBC_2.34 symbol version for it.
The symbols were moved using scripts/move-symbol-to-libc.py.
__pthread_mutexattr_init cannot be be made a compat symbol because
it is used in mtx_init, which is still in libpthread.
The symbols were moved using scripts/move-symbol-to-libc.py.
And pthread_mutexattr_getkind_np as a compatibility symbol.
(There is no declaration in <pthread.h>, so there is no need
to add an alias or a deprecation warning there.)
The symbols were moved using scripts/move-symbol-to-libc.py.
And __pthread_mutexattr_destroy as a compat symbol (so no
GLIBC_2.34 symbol version is added for it).
The symbols were moved using scripts/move-symbol-to-libc.py.
The symbols were moved using scripts/move-symbol-to-libc.py.
__pthread_mutex_trylock is used to implement mtx_timedlock,
which still resides in libpthread, so add a GLIBC_2.34 version
for it, to match the existing GLIBC_2.0 version.
The symbols were moved using scripts/move-symbol-to-libc.py.
The symbol aliasing follows pthread_cond_timedwait et al.
Missing hidden prototypes had to be added to nptl/pthreadP.h
for consistency.
The symbol was moved using scripts/move-symbol-to-libc.py.
There is no new symbol version because of the compatibility symbol
status. The __pthread_atfork reference in nptl/Versions was unused.
The signal handler is exported as __nptl_setxid_sighandler, so
that the libpthread initialization code can install it. This
is sufficient for now because it is guarantueed to happen before
the first pthread_create call.
Onl pthread_cond_clockwait did not have a forwarder, so it needs
a new symbol version.
Some complications arise due to the need to supply hidden aliases,
GLIBC_PRIVATE exports (for the C11 condition variable implementation
that still remains in libpthread) and 64-bit time_t stubs.
pthread_cond_broadcast, pthread_cond_signal, pthread_cond_timedwait,
pthread_cond_wait, pthread_cond_clockwait have been moved using
scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This is complicated because of a second compilation of
nptl/pthread_mutex_lock.c via nptl/pthread_mutex_cond_lock.c.
PTHREAD_MUTEX_VERSIONS is introduced to suppress symbol versions
in that case.
The symbols __pthread_mutex_lock, __pthread_mutex_unlock,
__pthread_mutex_init, __pthread_mutex_destroy, pthread_mutex_lock,
pthread_mutex_unlock, pthread_mutex_init, pthread_mutex_destroy
have been moved using scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This is optimization is similar in spirit to the SINGLE_THREAD_P check
in the malloc implementation. Doing this in generic code allows us
to prioritize those cases which are likely to occur in single-threaded
programs (normal and recursive mutexes).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This is in preparation of moving the mutex code into libc.
__pthread_tunables_init is now called via __pthread_early_init.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The forwarders were only used internally, so new symbol versions
are needed. All symbols are moved at once because the forwarders
are no-ops if libpthread is not loaded, leading to inconsistencies
in case of a partial migration.
The symbols __pthread_rwlock_rdlock, __pthread_rwlock_unlock,
__pthread_rwlock_wrlock, pthread_rwlock_rdlock,
pthread_rwlock_unlock, pthread_rwlock_wrlock have been moved using
scripts/move-symbol-to-libc.py.
The __ symbol variants are turned into compat symbols, which is why they
do not receive a GLIBC_2.34 version.
The symbol was moved using scripts/move-symbol-to-libc.py.
tss_delete (still in libpthread) uses the __pthread_key_create
alias, so that is now exported under GLIBC_PRIVATE.
This initalization should only happen once for the main thread's TCB.
At present, auditors can achieve this by not linking against
libpthread. If libpthread becomes part of libc, doing this
initialization in libc would happen for every audit namespace,
or too late (if it happens from the main libc only). That's why
moving this code into ld.so seems the right thing to do, right after
the TCB initialization.
For !__ASSUME_SET_ROBUST_LIST ports, this also moves the symbol
__set_robust_list_avail into ld.so, as __nptl_set_robust_list_avail.
It also turned into a proper boolean flag.
Inline the __pthread_initialize_pids function because it seems no
longer useful as a separate function.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
No new symbol version is required because there was a forwarder.
The symbol has been moved using scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
No new symbol version is required because there was a forwarder.
The symbol has been moved using scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The pthread_exit symbol was moved using
scripts/move-symbol-to-libc.py. No new symbol version is needed
because there was a forwarder.
The new tests nptl/tst-pthread_exit-nothreads and
nptl/tst-pthread_exit-nothreads-static exercise the scenario
that pthread_exit is called without libpthread having been linked in.
This is not possible for the generic code, so these tests do not
live in sysdeps/pthread for now.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It's necessary to stub out __libc_disable_asynccancel and
__libc_enable_asynccancel via rtld-stubbed-symbols because the new
direct references to the unwinder result in symbol conflicts when the
rtld exception handling from libc is linked in during the construction
of librtld.map.
unwind-forcedunwind.c is merged into unwind-resume.c. libc now needs
the functions that were previously only used in libpthread.
The GLIBC_PRIVATE exports of __libc_longjmp and __libc_siglongjmp are
no longer needed, so switch them to hidden symbols.
The symbol __pthread_unwind_next has been moved using
scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>
And also the fork generation counter, __fork_generation. This
eliminates the need for __fork_generation_pointer.
call_once remains in libpthread and calls the exported __pthread_once
symbol.
pthread_once and __pthread_once have been moved using
scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This internal symbol is used as part of the longjmp implementation.
Rename the file from nptl/pt-cleanup.c to nptl/pthread_cleanup_upto.c
so that the pt-* files remain restricted to libpthread.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The definitions in libc are sufficient, the forwarders are no longer
needed.
The symbols have been moved using scripts/move-symbol-to-libc.py.
s390-linux-gnu and s390x-linux-gnu need a new version placeholder
to keep the GLIBC_2.19 symbol version in libpthread.
Tested on i386-linux-gnu, powerpc64le-linux-gnu, s390x-linux-gnu,
x86_64-linux-gnu. Built with build-many-glibcs.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This affects _pthread_cleanup_pop, _pthread_cleanup_pop_restore,
_pthread_cleanup_push, _pthread_cleanup_push_defer. The symbols
have been moved using scripts/move-symbol-to-libc.py.
No new symbol versions are added because the symbols are turned into
compatibility symbols at the same time.
__pthread_cleanup_pop and __pthread_cleanup_push are added as
GLIBC_PRIVATE symbols because they are also used internally, for
glibc's own cancellation handling.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It is still used internally. Since unwinding is now available
unconditionally, avoid indirect calls through function pointers loaded
from the stack by inlining the non-cancellation cleanup code. This
avoids a regression in security hardening.
The out-of-line __libc_cleanup_routine implementation is no longer
needed because the inline definition is now static __always_inline.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
libthread_db is loaded once GDB encounters libpthread, and at this
point, ld.so may not have been processed by GDB yet. As a result,
_rtld_global cannot be accessed by regular means from libthread_db.
To make this work until GDB can be fixed, acess _rtld_global through
a pointer stored in libpthread.
The new test does not reproduce bug 27744 with
--disable-hardcoded-path-in-tests, but is still a valid smoke test.
With --enable-hardcoded-path-in-tests, it is necessary to avoid
add-symbol-file because this can tickle a GDB bug.
Fixes commit 1daccf403b ("nptl: Move
stack list variables into _rtld_global").
Tested-by: Emil Velikov <emil.velikov@collabora.com>
UNREGISTER_ATFORK is now defined for all ports in register-atfork.h, so most
previous includes of fork.h actually only need register-atfork.h now, and
cxa_finalize.c does not need an ifdef UNREGISTER_ATFORK any more.
The nptl-specific fork generation counters can then go to pthreadP.h, and
fork.h be removed.
Checked on x86_64-linux-gnu and i686-gnu.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The Linux version already target the current thread by using tgkill
along with getpid and gettid.
For arm, libpthread does not do a intra PLT since it will call the
raise from libc.
Checked on x86_64-linux-gnu.
The libc version is identical and built with same flags. The libc
version is set as the default version.
The libpthread compat symbol requires to mask it when building the
loader object otherwise ld might complain about a missing
versioned symbol (as for alpha).
Checked on x86_64-linux-gnu.
The libc version is identical and built with same flags. Both aarch64
and nios2 also requires to export __send and tt was done previously with
the HAVE_INTERNAL_SEND_SYMBOL (which forced the symbol creation).
All __send callers are internal to libc and the original issue that
required the symbol export was due a missing libc_hidden_def. So
a compat symbol is added for __send and the libc_hidden_def is
defined regardless.
Checked on x86_64-linux-gnu and i686-linux-gnu.
This essentially folds compat_symbol_unique functionality into
compat_symbol.
This change eliminates the need for intermediate aliases for defining
multiple symbol versions, for both compat_symbol and versioned_symbol.
Some binutils versions do not suport multiple versions per symbol on
some targets, so aliases are automatically introduced, similar to what
compat_symbol_unique did. To reduce symbol table sizes, a configure
check is added to avoid these aliases if they are not needed.
The new mechanism works with data symbols as well as function symbols,
due to the way an assembler-level redirect is used. It is not
compatible with weak symbols for old binutils versions, which is why
the definition of __malloc_initialize_hook had to be changed. This
is not a loss of functionality because weak symbols do not matter
to dynamic linking.
The placeholder symbol needs repeating in nptl/libpthread-compat.c
now that compat_symbol is used, but that seems more obvious than
introducing yet another macro.
A subtle difference was that compat_symbol_unique made the symbol
global automatically. compat_symbol does not do this, so static
had to be removed from the definition of
__libpthread_version_placeholder.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The generic implementation basically handle the system agnostic logic
(filtering out the invalid signals) while the __libc_sigaction is
the function with implements the system and architecture bits.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Both htl and nptl uses a different data structure to implement atfork
handlers. The nptl one was refactored by 27761a1042 to use a dynarray
which simplifies the code.
This patch moves the nptl one to be the generic implementation and
replace Hurd linked one. Different than previous NPTL, Hurd also uses
a global lock, so performance should be similar.
Checked on x86_64-linux-gnu, i686-linux-gnu, and with a build for
i686-gnu.
The nptl already expects a Linux syscall internally. Also
__is_internal_signal is used and the DEBUGGING_P check is removed.
Checked on x86_64-linux-gnu.
This is another attempt at making pthread_once handle throwing exceptions
from the init routine callback. As the new testcases show, just switching
to the cleanup attribute based cleanup does fix the tst-once5 test, but
breaks the new tst-oncey3 test. That is because when throwing exceptions,
only the unwind info registered cleanups (i.e. C++ destructors or cleanup
attribute), when cancelling threads and there has been unwind info from the
cancellation point up to whatever needs cleanup both unwind info registered
cleanups and THREAD_SETMEM (self, cleanup, ...) registered cleanups are
invoked, but once we hit some frame with no unwind info, only the
THREAD_SETMEM (self, cleanup, ...) registered cleanups are invoked.
So, to stay fully backwards compatible (allow init routines without
unwind info which encounter cancellation points) and handle exception throwing
we actually need to register the pthread_once cleanups in both unwind info
and in the THREAD_SETMEM (self, cleanup, ...) way.
If an exception is thrown, only the former will happen and we in that case
need to also unregister the THREAD_SETMEM (self, cleanup, ...) registered
handler, because otherwise after catching the exception the user code could
call deeper into the stack some cancellation point, get cancelled and then
a stale cleanup handler would clobber stack and probably crash.
If a thread calling init routine is cancelled and unwind info ends before
the pthread_once frame, it will be cleaned up through self->cleanup as
before. And if unwind info is present, unwind_stop first calls the
self->cleanup registered handler for the frame, then it will call the
unwind info registered handler but that will already see __do_it == 0
and do nothing.
The elision interfaces are closely aligned between the targets that
implement them, so declare them in the generic <lowlevellock.h>
file.
Empty .c stubs are provided, so that fewer makefile updates
under sysdeps are needed. Also simplify initialization via
__libc_early_init.
The symbols __lll_clocklock_elision, __lll_lock_elision,
__lll_trylock_elision, __lll_unlock_elision, __pthread_force_elision
move into libc. For the time being, non-hidden references are used
from libpthread to access them, but once that part of libpthread
is moved into libc, hidden symbols will be used again. (Hidden
references seem desirable to reduce the likelihood of transactions
aborts.)
This moves __futex_abstimed_wait64 and
__futex_abstimed_wait_cancelable64 and exports these functions as
GLIBC_PRIVATE.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
And sort the lines lexicographically. This will make it easier to review
patches which move symbols from libpthread to libc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The internal semaphore list code is moved to a specific file,
sem_routine.c, and the internal usage is simplified to only two
functions (one to insert a new semaphore and one to remove it
from the internal list). There is no need to expose the
internal locking, neither how the semaphore mapping is implemented.
No functional or semantic change is expected, tested on
x86_64-linux-gnu.
Previously, glibc would pick an arbitrary tmpfs file system from
/proc/mounts if /dev/shm was not available. This could lead to
an unsuitable file system being picked for the backing storage for
shm_open, sem_open, and related functions.
This patch introduces a new function, __shm_get_name, which builds
the file name under the appropriate (now hard-coded) directory. It is
called from the various shm_* and sem_* function. Unlike the
SHM_GET_NAME macro it replaces, the callers handle the return values
and errno updates. shm-directory.c is moved directly into the posix
subdirectory because it can be implemented directly using POSIX
functionality. It resides in libc because it is needed by both
librt and nptl/htl.
In the sem_open implementation, tmpfname is initialized directly
from a string constant. This happens to remove one alloca call.
Checked on x86_64-linux-gnu.
I've updated copyright dates in glibc for 2021. This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files. As well as the usual annual
updates, mainly dates in --version output (minus csu/version.c which
previously had to be handled manually but is now successfully updated
by update-copyrights), there is a small change to the copyright notice
in NEWS which should let NEWS get updated automatically next year.
Please remember to include 2021 in the dates for any new files added
in future (which means updating any existing uncommitted patches you
have that add new files to use the new copyright dates in them).
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
The earlier implementation of this, __lll_clocklock, calls lll_clockwait
that doesn't return the futex syscall error codes. It always tries again
if that fails.
However in the current implementation, when the futex returns EAGAIN,
__futex_clocklock64 will also return EGAIN, even if the futex is taken.
This patch fixes the EAGAIN issue and also adds a check for EINTR. As
futex syscall can return EINTR if the thread is interrupted by a signal.
In this case I'm assuming the function should continue trying to lock as
there is no mention to about it on POSIX. Also add a test for both
scenarios.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The aio_suspend function has been converted to support 64 bit time.
This change uses (in aio_misc.h):
- __futex_abstimed_wait64 (instead of futex_reltimed_wait)
- __futex_abstimed_wait_cancellable64
(instead of futex_reltimed_wait_cancellable)
from ./sysdeps/nptl/futex-helpers.h
The aio_suspend() accepts relative timeout, which then is converted to
absolute one.
The i686-gnu port (HURD) do not define DONT_NEED_AIO_MISC_COND and as it
doesn't (yet) support 64 bit time it uses not converted
pthread_cond_timedwait().
The __aio_suspend() is supposed to be run on ports with __TIMESIZE !=64 and
__WORDSIZE==32. It internally utilizes __aio_suspend_time64() and hence the
conversion from 32 bit struct timespec to 64 bit one is required.
For ports supporting 64 bit time the __aio_suspend_time64() will be used
either via alias (to __aio_suspend when __TIMESIZE==64) or redirection
(when -D_TIME_BITS=64 is passed).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Some futex-internal calls require additional check for EOVERFLOW (as
indicated by [1] [2] [3]). For both mutex and rwlock code, EOVERFLOW is
handle as ETIMEDOUT; since it indicate to the caller that the blocking
operation could not be issued.
For mutex it avoids a possible issue where PTHREAD_MUTEX_ROBUST_* might
assume EOVERFLOW indicate futex has succeed, and for PTHREAD_MUTEX_PP_*
it avoid a potential busy infinite loop. For rwlock and semaphores, it
also avoids potential busy infinite loops.
Checked on x86_64-linux-gnu and i686-linux-gnu, although EOVERFLOW
won't be possible with current usage (since all timeouts on 32-bit
architectures with 32-bit time_t support will be in the range of
32-bit time_t).
[1] https://sourceware.org/pipermail/libc-alpha/2020-November/120079.html
[2] https://sourceware.org/pipermail/libc-alpha/2020-November/120080.html
[3] https://sourceware.org/pipermail/libc-alpha/2020-November/120127.html
The 878fe624d4 changed lll_futex_timed_wait, which expects a relative
timeout, with a __futex_abstimed_wait64, which expects an absolute
timeout. However the code still passes a relative timeout.
Also, the PTHREAD_PRIO_PROTECT support for clocks different than
CLOCK_REALTIME was broken since the inclusion of
pthread_mutex_clocklock (9d20e22e46) since lll_futex_timed_wait
always use CLOCK_REALTIME.
This patch fixes by removing the relative time calculation. It
also adds some xtests that tests both thread and inter-process
usage.
Checked on x86_64-linux-gnu.
The align the GNU extension with the others one that accept specify
which clock to wait for (such as pthread_mutex_clocklock).
Check on x86_64-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Linux futex FUTEX_LOCK_PI operation only supports CLOCK_REALTIME,
so pthread_mutex_clocklock operation with priority aware mutexes
may fail depending of the input timeout.
Also, it is not possible to convert a CLOCK_MONOTONIC to a
CLOCK_REALTIME due the possible wall clock time change which might
invalid the requested timeout.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
The idea is to make NPTL implementation to use on the functions
provided by futex-internal.h.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
The idea is to make NPTL implementation to use on the functions
provided by futex-internal.h.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
The idea is to make NPTL implementation to use on the functions
provided by futex-internal.h.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
For non null timeouts, the __futex_clocklock_wait64 creates an a
relative timeout by subtracting the current time from the input
argument. The same behavior can be obtained with FUTEX_WAIT_BITSET
without the need to calculate the relative timeout. Besides consolidate
the code it also avoid the possible relative timeout issues [1].
The __futex_abstimed_wait64 needs also to return EINVAL syscall
errors.
Checked on x86_64-linux-gnu and i686-linux-gnu.
[1] https://sourceware.org/pipermail/libc-alpha/2020-November/119881.html
Reviewed-by: Lukasz Majewski <lukma@denx.de>
It can be replaced with a __futex_abstimed_wait_cancelable64 call,
with the advantage that there is no need to further clock adjustments
to create a absolute timeout. It allows to remove the now ununsed
futex_timed_wait_cancel64 internal function.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
It is used solely on __pthread_cond_wait_common and the call can be
replaced by a __futex_abstimed_wait_cancelable64 one.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
The __futex_abstimed_wait usage was remove with 3102e28bd1 and the
__futex_abstimed_wait_cancelable by 323592fdc9 and b8d3e8fbaa.
The futex_lock_pi can be replaced by a futex_lock_pi64.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
On GNU/Hurd we not only need $(common-objpfx) in LD_LIBRARY_PATH when loading
dynamic objects, but also $(common-objpfx)/mach and $(common-objpfx)/hurd. This
adds an ld-library-path variable to be used as LD_LIBRARY_PATH basis in
Makefiles, and a sysdep-ld-library-path variable for sysdeps to add some
more paths, here mach/ and hurd/.
Now __thread_gscope_wait (the function behind THREAD_GSCOPE_WAIT,
formerly __wait_lookup_done) can be implemented directly in ld.so,
eliminating the unprotected GL (dl_wait_lookup_done) function
pointer.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Most systems are SMP, so optimizing for the UP case is no longer
approriate. A dynamic check based on the kernel identification
has been only implemented for i386 anyway.
To disable adaptive mutexes on sh, define DEFAULT_ADAPTIVE_COUNT
as zero for this architecture.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
commit def674652e
Author: Florian Weimer <fweimer@redhat.com>
Date: Mon Apr 27 15:00:14 2020 +0200
nptl/tst-setuid1-static: Improve isolation from system objects
Static dlopen needs an LD_LIBRARY_PATH setting to avoid loading system
libraries.
missed $(common-objpfx)nss. Add $(common-objpfx)nss to LD_LIBRARY_PATH
for tst-setuid1-static to support
struct passwd *pwd = getpwnam ("nobody");
in nptl/tst-setuid1.c.
Building glibc with GCC 11 fails with (among other warnings) spurious
-Wstringop-overflow warnings from calls to setjmp and longjmp with a
pointer to a pthread_unwind_buf that is smaller than jmp_buf. As
discussed in bug 26647, the warning in libc-start.c is a false
positive, because setjmp and longjmp do not access anything (the
signal mask) beyond the common prefix of the two structures, so this
patch disables the warning for that call to setjmp, as well as for two
calls in NPTL code that produce the same warning and look like false
positives for the same reason.
Tested with build-many-glibcs.py for arm-linux-gnueabi, where this
allows the build to get further.
Reviewed-by: DJ Delorie <dj@redhat.com>
The commit:
"y2038: nptl: Convert pthread_mutex_{clock|timed}lock to support 64 bit"
SHA1: 29e9874a04
introduced support for 64 bit timeouts. Unfortunately, it was missing the
code for bitset - i.e. lll_futex_clock_wait_bitset C preprocessor macro
was used. As a result the 64 bit struct __timespec64 was coerced to 32
bit struct timespec and regression visible as timeout was observed
(nptl/tst-robust10 on s390).
Reported-by: Stefan Liebler <stli@linux.ibm.com>
Tested-by: Stefan Liebler <stli@linux.ibm.com>
The pthread_mutex_clocklock and pthread_mutex_timedlock have been converted
to support 64 bit time.
This change uses:
- New __futex_clocklock_wait64 (instead of lll_timedwait)
from ./sysdeps/nptl/futex-helpers.c and
- New __futex_clocklock64 function (instead of lll_clocklock)
- New futex_lock_pi64
defined in sysdeps/nptl/futex-internal.h
The pthread_mutex_{clock|timed}lock only accepts absolute time.
Moreover, there is no need to check for NULL passed as *abstime pointer to the
syscalls as those calls have exported symbols marked with __nonull attribute
for abstime.
Some architectures - namely x86, powerpc and s390 - do support lock elision.
For those - adjustments have been made in arch specific elision-*.c files
to use __futex_clocklock64 instead of lll_clocklock.
The __lll_lock_elision (aliased to __lll_clocklock_elision in e.g.
sysdeps/unix/sysv/linux/s390/elision-timed.c) just uses, in this patch
provided, __futex_clocklock64.
For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversions between 64 bit time to 32 bit are necessary
- Redirection to pthread_mutex_{clock|timed}lock will provide support for 64
bit time
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The pthread_rwlock_clockrdlock, pthread_rwlock_clockwrlock,
pthread_rwlock_timedrdlock and pthread_rwlock_timedwrlock have been converted
to support 64 bit time.
This change uses new futex_abstimed_wait64 function in
./sysdeps/nptl/futex-helpers.c, which uses futex_time64 where possible.
The pthread_rwlock_{clock|timed}{rd|wr}lock only accepts absolute time.
Moreover, there is no need to check for NULL passed as *abstime pointer to the
syscalls as those calls have exported symbols marked with __nonull attribute
for abstime.
For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversions between 64 bit time to 32 bit are necessary
- Redirection to pthread_rwlock_{clock|timed}{rd|wr}lock will provide support
for 64 bit time
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test the proper usage of both __pthread_rwlock_{clock|timed}{rd|wr}lock64
and __pthread_rwlock_{clock|timed}{rd|wr}lock.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
There are several compiler implementations that allow large stack
allocations to jump over the guard page at the end of the stack and
corrupt memory beyond that. See CVE-2017-1000364.
Compilers can emit code to probe the stack such that the guard page
cannot be skipped, but on aarch64 the probe interval is 64K by default
instead of the minimum supported page size (4K).
This patch enforces at least 64K guard on aarch64 unless the guard
is disabled by setting its size to 0. For backward compatibility
reasons the increased guard is not reported, so it is only observable
by exhausting the address space or parsing /proc/self/maps on linux.
On other targets the patch has no effect. If the stack probe interval
is larger than a page size on a target then ARCH_MIN_GUARD_SIZE can
be defined to get large enough stack guard on libc allocated stacks.
The patch does not affect threads with user allocated stacks.
Fixes bug 26691.
The sem_clockwait and sem_timedwait have been converted to support 64 bit time.
This change reuses futex_abstimed_wait_cancelable64 function introduced earlier.
The sem_{clock|timed}wait only accepts absolute time. Moreover, there is no
need to check for NULL passed as *abstime pointer to the syscalls as both calls
have exported symbols marked with __nonull attribute for abstime.
For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversion from 32 bit time to 64 bit struct __timespec64 was necessary
- Redirection to __sem_{clock|timed}wait64 will provide support for 64 bit
time
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test the proper usage of both __sem_{clock|timed}wait64 and
__sem_{clock|timed}wait.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It replaces the internal usage of __{f,l}xstat{at}{64} with the
__{f,l}stat{at}{64}. It should not change the generate code since
sys/stat.h explicit defines redirections to internal calls back to
xstat* symbols.
Checked with a build for all affected ABIs. I also check on
x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
The pthread_cond_clockwait and pthread_cond_timedwait have been converted
to support 64 bit time.
This change introduces new futex_abstimed_wait_cancelable64 function in
./sysdeps/nptl/futex-helpers.c, which uses futex_time64 where possible
and tries to replace low-level preprocessor macros from
lowlevellock-futex.h
The pthread_cond_{clock|timed}wait only accepts absolute time. Moreover,
there is no need to check for NULL passed as *abstime pointer as
__pthread_cond_wait_common() always passes non-NULL struct __timespec64
pointer to futex_abstimed_wait_cancellable64().
For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversions between 64 bit time to 32 bit are necessary
- Redirection to __pthread_cond_{clock|timed}wait64 will provide support
for 64 bit time
The futex_abstimed_wait_cancelable64 function has been put into a separate
file on the purpose - to avoid issues apparent on the m68k architecture
related to small number of available registers (there is not enough
registers to put all necessary arguments in them if the above function
would be added to futex-internal.h with __always_inline attribute).
In fact - new function - namely __futex_abstimed_wait_cancellable32 is
used to reduce number of needed registers (as some in-register values are
stored on the stack when function call is made).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test the proper usage of both __pthread_cond_{clock|timed}wait64 and
__pthread_cond_{clock|timed}wait.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The pthread_clockjoin_np and pthread_timedjoin_np have been converted to
support 64 bit time.
This change introduces new futex_timed_wait_cancel64 function in
./sysdeps/nptl/futex-internal.h, which uses futex_time64 where possible
and tries to replace low-level preprocessor macros from
lowlevellock-futex.h
The pthread_{timed|clock}join_np only accept absolute time. Moreover,
there is no need to check for NULL passed as *abstime pointer as
clockwait_tid() always passes struct __timespec64.
For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversions between 64 bit time to 32 bit are necessary
- Redirection to __pthread_{clock|timed}join_np64 will provide support
for 64 bit time
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test the proper usage of both __pthread_{timed|clock}join_np64 and
__pthread_{timed|clock}join_np.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
nptl has
/* Opcodes and data types for communication with the signal handler to
change user/group IDs. */
struct xid_command
{
int syscall_no;
long int id[3];
volatile int cntr;
volatile int error;
};
/* This must be last, otherwise the current thread might not have
permissions to send SIGSETXID syscall to the other threads. */
result = INTERNAL_SYSCALL_NCS (cmdp->syscall_no, 3,
cmdp->id[0], cmdp->id[1], cmdp->id[2]);
But the second argument of setgroups syscal is a pointer:
int setgroups (size_t size, const gid_t *list);
But on x32, pointers passed to syscall must have pointer type so that
they will be zero-extended. The kernel XID arguments are unsigned and
do not require sign extension. Change xid_command to
struct xid_command
{
int syscall_no;
unsigned long int id[3];
volatile int cntr;
volatile int error;
};
so that all arguments are zero-extended. A testcase is added for x32 and
setgroups returned with EFAULT when running as root without the fix.
The kernel ABI is not finalized, and there are now various proposals
to change the size of struct rseq, which would make the glibc ABI
dependent on the version of the kernels used for building glibc.
This is of course not acceptable.
This reverts commit 48699da1c4 ("elf:
Support at least 32-byte alignment in static dlopen"), commit
8f4632deb3 ("Linux: rseq registration
tests"), commit 6e29cb3f61 ("Linux: Use
rseq in sched_getcpu if available"), and commit
0c76fc3c2b ("Linux: Perform rseq
registration at C startup and thread creation"), resolving the conflicts
introduced by the ARC port and the TLS static surplus changes.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The per-thread state is refactored two use two strategies:
1. The default one uses a TLS structure, which will be placed in the
static TLS space (using __thread keyword).
2. Linux allocates via struct pthread and access it through THREAD_*
macros.
The default strategy has the disadvantage of increasing libc.so static
TLS consumption and thus decreasing the possible surplus used in
some scenarios (which might be mitigated by BZ#25051 fix).
It is used only on Hurd, where accessing the thread storage in the in
single thread case is not straightforward (afaiu, Hurd developers could
correct me here).
The fallback static allocation used for allocation failure is also
removed: defining its size is problematic without synchronizing with
translated messages (to avoid partial translation) and the resulting
usage is not thread-safe.
Checked on x86-64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
and s390x-linux-gnu.
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The __NSIG_WORDS value is based on minimum number of words to hold
the maximum number of signals supported by the architecture.
This patch also adds __NSIG_BYTES, which is the number of bytes
required to represent the supported number of signals. It is used in
syscalls which takes a sigset_t.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The variable is placed in libc.so, and it can be true only in
an outer libc, not libcs loaded via dlmopen or static dlopen.
Since thread creation from inner namespaces does not work,
pthread_create can update __libc_single_threaded directly.
Using __libc_early_init and its initial flag, implementation of this
variable is very straightforward. A future version may reset the flag
during fork (but not in an inner namespace), or after joining all
threads except one.
Reviewed-by: DJ Delorie <dj@redhat.com>
Register rseq TLS for each thread (including main), and unregister for
each thread (excluding main). "rseq" stands for Restartable Sequences.
See the rseq(2) man page proposed here:
https://lkml.org/lkml/2018/9/19/647
Those are based on glibc master branch commit 3ee1e0ec5c.
The rseq system call was merged into Linux 4.18.
The TLS_STATIC_SURPLUS define is increased to leave additional room for
dlopen'd initial-exec TLS, which keeps elf/tst-auditmany working.
The increase (76 bytes) is larger than 32 bytes because it has not been
increased in quite a while. The cost in terms of additional TLS storage
is quite significant, but it will also obscure some initial-exec-related
dlopen failures.
The Hurd port doesn't have support for sigwaitinfo, sigtimedwait, and msgget
yet, so let us ignore the test for these when they return ENOSYS.
* nptl/tst-cancel4.c (tf_sigwaitinfo): Fallback on sigwait when
sigwaitinfo returns ENOSYS.
(tf_sigtimedwait): Likewise with sigtimedwait.
(tf_msgrcv, tf_msgsnd): Fallback on tf_usleep when msgget returns ENOSYS.
PF_UNIX was actually never intended to be passed as protocol parameter to
socket() calls: it is a protocol family, not a protocol. It happens that
Linux introduced accepting it during its 2.0 development, but it shouldn't.
OpenBSD kernels accept it as well, but FreeBSD and NetBSD rightfully do not.
GNU/Hurd does not either.
* nptl/tst-cancel4-common.c (do_test): Pass 0 instead of PF_UNIX as
protocol.
User provided stack should not be released nor madvised at
thread exit because it's owned by the user.
If the memory is shared or file based then MADV_DONTNEED
can have unwanted effects. With memory tagging on aarch64
linux the tags are dropped and thus it may invalidate
pointers.
Tested on aarch64-linux-gnu with MTE, it fixes
FAIL: nptl/tst-stack3
FAIL: nptl/tst-stack3-mem
By aligning its implementation on pthread_cond_wait.
* sysdeps/htl/sem-timedwait.c (cancel_ctx): New structure.
(cancel_hook): New function.
(__sem_timedwait_internal): Check for cancellation and register
cancellation hook that wakes the thread up, and check again for
cancellation on exit.
* nptl/tst-cancel13.c, nptl/tst-cancelx13.c: Move to...
* sysdeps/pthread/: ... here.
* nptl/Makefile: Move corresponding references and rules to...
* sysdeps/pthread/Makefile: ... here.
* nptl/tst-cancel25.c: Move to...
* sysdeps/pthread/tst-cancel25.c: ... here.
(tf2) Do not test for SIGCANCEL when it is not defined.
* nptl/Makefile: Move corresponding reference to...
* sysdeps/pthread/Makefile: ... here.
They were to be moved to sysdeps/pthread/Makefile in 45fce058f ('htl:
Enable more cancellation tests')
* nptl/Makefile: (tests): Remove tst-cancelx9.
(CFLAGS-tst-cancelx9.c): Remove.
d6d74ec16 ('htl: Enable more tests') moved the linking rules from
nptl/Makefile and htl/Makefile to the shared sysdeps/pthread/Makefile. But
e.g. on powerpc some tests are added in sysdeps/powerpc/Makefile, which is
included *after* sysdeps/pthread/Makefile, and thus the tests don't get
affected by the rules and fail to link. For now let's just copy over the
set of rules in both nptl/Makefile and htl/Makefile.
* sysdeps/pthread/Makefile: Move libpthread linking rules to...
* htl/Makefile: ... here and...
* nptl/Makefile: ... there.
This introduces the function __pthread_attr_extension to allocate the
extension space, which is freed by pthread_attr_destroy.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
union pthread_attr_transparent has always the correct size, even if
pthread_attr_t has padding that is not present in struct pthread_attr.
This should not result in an observable behavioral change. The
existing code appears to have been correct, but it was brittle because
it was not clear which functions were allowed to write to an entire
pthread_attr_t argument (e.g., by copying it).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This allows to reuse the storage after calling pthread_cond_destroy.
* sysdeps/htl/bits/types/struct___pthread_cond.h (__pthread_cond):
Replace unused struct __pthread_condimpl *__impl field with unsigned int
__wrefs.
(__PTHREAD_COND_INITIALIZER): Update accordingly.
* sysdeps/htl/pt-cond-timedwait.c (__pthread_cond_timedwait_internal):
Register as waiter in __wrefs field. On unregistering, wake any pending
pthread_cond_destroy.
* sysdeps/htl/pt-cond-destroy.c (__pthread_cond_destroy): Register wake
request in __wrefs.
* nptl/Makefile (tests): Move tst-cond20 tst-cond21 to...
* sysdeps/pthread/Makefile (tests): ... here.
* nptl/tst-cond20.c nptl/tst-cond21.c: Move to...
* sysdeps/pthread/tst-cond20.c sysdeps/pthread/tst-cond21.c: ... here.
This needs a few test adjustments: In some cases, sigignore was
used for convenience (replaced with xsignal with SIG_IGN). Tests
for the deprecated functions need to disable
-Wdeprecated-declarations, and for the sigmask deprecation,
-Wno-error.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Also add the private type union pthread_attr_transparent, to reduce
the amount of casting that is required.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
pthread_attr_destroy needs to be a weak alias to avoid future
linknamespace failures.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
Use __getline instead of __getdelim to avoid a localplt failure.
Likewise for __getrlimit/getrlimit.
The abilist updates were performed by:
git ls-files 'sysdeps/unix/sysv/linux/**/libc.abilist' \
| while read x ; do
echo "GLIBC_2.32 pthread_getattr_np F" >> $x
done
python3 scripts/move-symbol-to-libc.py --only-linux pthread_getattr_np
The private export of __pthread_getaffinity_np is no longer needed, but
the hidden alias still necessary so that the symbol can be exported with
versioned_symbol.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
The abilist updates were performed by:
git ls-files 'sysdeps/unix/sysv/linux/**/libc.abilist' \
| while read x ; do
echo "GLIBC_2.32 pthread_getaffinity_np F" >> $x
done
python3 scripts/move-symbol-to-libc.py pthread_getaffinity_np
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
The symbol did not previously exist in libc, so a new GLIBC_2.32
symbol is needed, to get correct dependency for binaries which
use the symbol but no longer link against libpthread.
The abilist updates were performed by:
git ls-files 'sysdeps/unix/sysv/linux/**/libc.abilist' \
| while read x ; do
echo "GLIBC_2.32 pthread_attr_setaffinity_np F" >> $x
done
python3 scripts/move-symbol-to-libc.py pthread_attr_setaffinity_np
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The stubs for pthread_getaffinity_np, pthread_getname_np,
pthread_setaffinity_np, pthread_setname_np are replaced, and corresponding
tests are moved.
After the removal of the NaCl port, nptl is Linux-specific, and the stubs
are no longer needed. This effectively reverts commit
c76d1ff514 ("NPTL: Add stubs for Linux-only
extension functions.").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
There is a race between __nptl_setxid and exiting detached thread, which
causes a deadlock on stack_cache_lock. The deadlock happens in this
state:
T1: setgroups -> __nptl_setxid (holding stack_cache_lock, waiting on cmdp->cntr == 0)
T2 (detached, exiting): start_thread -> __deallocate_stack (waiting on stack_cache_lock)
more threads waiting on stack_cache_lock in pthread_create
For non-detached threads, start_thread waits for its own setxid handler to
finish before exiting. Do this for detached threads as well.
New threads inherit the signal mask from the current thread. This
means that signal handlers can run on the newly created thread
immediately after the kernel has created the userspace thread, even
before glibc has initialized the TCB. Consequently, new threads can
observe uninitialized ctype data, among other things.
To address this, block all signals before starting the thread, and
pass the original signal mask to the start routine wrapper. On the
new thread, first perform all thread initialization, and then unblock
signals.
The cost of doing this is two rt_sigprocmask system calls on the old
thread, and one rt_sigprocmask system call on the new thread. (If
there was a way to clone a new thread with a signals disabled, this
could be brought down to one system call each.) The thread descriptor
increases in size, too, and sigset_t is fairly large. This increase
could be brought down by reusing space the in the descriptor which is
not needed before running user code, or by switching to an internal
sigset_t definition which only covers the signals supported by the
kernel definition. (Part of the thread descriptor size increase is
already offset by reduced stack usage in the thread start wrapper
routine after this commit.)
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The upper bits of the sigset_t s not fully initialized in the signal
mask calls that return information from kernel (sigprocmask,
sigpending, and pthread_sigmask), since the exported sigset_t size
(1024 bits) is larger than Linux support one (64 or 128 bits).
It might make sigisemptyset/sigorset/sigandset fail if the mask
is filled prior the call.
This patch changes the internal signal function to handle up to
supported Linux signal number (_NSIG), the remaining bits are
untouched.
Checked on x86_64-linux-gnu and i686-linux-gnu.
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
A new symbol version is added on libc to force loading failure
instead of lazy binding one for newly binaries with old loaders.
Checked with a build against all affected ABIs.
Due to the built-in tables, __NR_set_robust_list is always defined
(although it may not be available at run time).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It is necessary to export __pthread_cond_init from libc because
the C11 condition variable needs it and is still left in libpthread.
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It is necessary to export __pthread_cond_destroy from libc because
the C11 condition variable needs it and is still left in libpthread.
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This will make it easier to review changes which move implementations
from libpthread to libc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The behavior of the signal mask on threads created by timer_create
for SIGEV_THREAD timers are implementation-defined and glibc explicit
unblocks all signals before calling the user-defined function.
This behavior, although not incorrect standard-wise, opens a race if a
program using a blocked rt-signal plus sigwaitinfo (and without an
installed signal handler for the rt-signal) receives a signal while
executing the used-defined function for SIGEV_THREAD.
A better alternative discussed in bug report is to rather block all
signals (besides the internal ones not available to application
usage).
This patch fixes this issue by only unblocking SIGSETXID (used on
set*uid function) and SIGCANCEL (used for thread cancellation).
Checked on x86_64-linux-gnu and i686-linux-gnu.
This supersedes the init_array sysdeps directory. It allows us to
check for ELF_INITFINI in both C and assembler code, and skip DT_INIT
and DT_FINI processing completely on newer architectures.
A new header file is needed because <dl-machine.h> is incompatible
with assembler code. <sysdep.h> is compatible with assembler code,
but it cannot be included in all assembler files because on some
architectures, it redefines register names, and some assembler files
conflict with that.
<elf-initfini.h> is replicated for legacy architectures which need
DT_INIT/DT_FINI support. New architectures follow the generic default
and disable it.
With all Linux ABIs using the expected Linux kABI to indicate
syscalls errors, the INTERNAL_SYSCALL_DECL is an empty declaration
on all ports.
This patch removes the 'err' argument on INTERNAL_SYSCALL* macro
and remove the INTERNAL_SYSCALL_DECL usage.
Checked with a build against all affected ABIs.
so it gets shared by nptl and htl. Also add htl versions of thrd_current and
thrd_yield.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
See https://bugzilla.redhat.com/show_bug.cgi?id=1653942
This test depends on the kernel's assignment of memory regions, but
running under ld.so explicitly changes those assignments, sometimes
sufficiently to cause the test to fail (esp with address space
randomization).
The easiest way to "fix" the test, is to run it the way the user would
- without ld.so. Running it in a container does that.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
I've updated copyright dates in glibc for 2020. This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files. As well as the usual annual
updates, mainly dates in --version output (minus libc.texinfo which
previously had to be handled manually but is now successfully updated
by update-copyrights), there is a fix to
sysdeps/unix/sysv/linux/powerpc/bits/termios-c_lflag.h where a typo in
the copyright notice meant it failed to be updated automatically.
Please remember to include 2020 in the dates for any new files added
in future (which means updating any existing uncommitted patches you
have that add new files to use the new copyright dates in them).
This patch adds the missing __libpthread_version_placeholder for
GLIBC_2.2.6 version from the nanosleep implementation move from
libpthread to libc (79a547b162).
It also fixes the wrong compat symbol definitions added by changing
back the version used on vfork check and remove the
__libpthread_version_placeholder added on some ABI (4f4bb489e0).
The __libpthread_version_placeholder is also refactored to make it
simpler to add new compat_symbols by adding a new macro
compat_symbol_unique which uses the compiler extension __COUNTER__
to generate unique strong alias to be used with compat_symbol.
Checked with a updated-abi on the all affected abis of the nanosleep
move.
Change-Id: I347a4dbdc931bb42b359456932dd1e17aa4d4078
Since commit a3cc4f48e9 ("Remove
--as-needed configure test."), --as-needed support is no longer
optional.
The macros are not much shorter and do not provide documentary
value, either, so this commit removes them.
This patch adds a new generic __pthread_rwlock_arch_t definition meant
to be used by new ports. Its layout mimics the current usage on some
64 bits ports and it allows some ports to use the generic definition.
The arch __pthread_rwlock_arch_t definition is moved from
pthreadtypes-arch.h to another arch-specific header (struct_rwlock.h).
Also the static intialization macro for pthread_rwlock_t is set to use
an arch defined on (__PTHREAD_RWLOCK_INITIALIZER) which simplifies its
implementation.
The default pthread_rwlock_t layout differs from current ports with:
1. Internal layout is the same for 32 bits and 64 bits.
2. Internal flag is an unsigned short so it should not required
additional padding to align for word boundary (if it is the case
for the ABI).
Checked with a build on affected abis.
Change-Id: I776a6a986c23199929d28a3dcd30272db21cd1d0
The current way of defining the common mutex definition for POSIX and
C11 on pthreadtypes-arch.h (added by commit 06be6368da) is
not really the best options for newer ports. It requires define some
misleading flags that should be always defined as 0
(__PTHREAD_COMPAT_PADDING_MID and __PTHREAD_COMPAT_PADDING_END), it
exposes options used solely for linuxthreads compat mode
(__PTHREAD_MUTEX_USE_UNION and __PTHREAD_MUTEX_NUSERS_AFTER_KIND), and
requires newer ports to explicit define them (adding more boilerplate
code).
This patch adds a new default __pthread_mutex_s definition meant to
be used by newer ports. Its layout mimics the current usage on both
32 and 64 bits ports and it allows most ports to use the generic
definition. Only ports that use some arch-specific definition (such
as hardware lock-elision or linuxthreads compat) requires specific
headers.
For 32 bit, the generic definitions mimic the other 32-bit ports
of using an union to define the fields uses on adaptive and robust
mutexes (thus not allowing both usage at same time) and by using a
single linked-list for robust mutexes. Both decisions seemed to
follow what recent ports have done and make the resulting
pthread_mutex_t/mtx_t object smaller.
Also the static intialization macro for pthread_mutex_t is set to use
a macro __PTHREAD_MUTEX_INITIALIZER where the architecture can redefine
in its struct_mutex.h if it requires additional fields to be
initialized.
Checked with a build on affected abis.
Change-Id: I30a22c3e3497805fd6e52994c5925897cffcfe13
This patch new build tests to check for internal fields offsets for
internal pthread_rwlock_t definition. Althoug the '__data.__flags'
field layout should be preserved due static initializators, the patch
also adds tests for the futexes that may be used in a shared memory
(although using different libc version in such scenario is not really
supported).
Checked with a build against all affected ABIs.
Change-Id: Iccc103d557de13d17e4a3f59a0cad2f4a640c148
The offsets of pthread_mutex_t __data.__nusers, __data.__spins,
__data.elision, __data.list are not required to be constant over
the releases. Only the __data.__kind is used for static
initializers.
This patch also adds an additional size check for __data.__kind.
Checked with a build against affected ABIs.
Change-Id: I7a4e48cc91b4c4ada57e9a5d1b151fb702bfaa9f
