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2019-02-14nptl: Reinstate pthread_timedjoin_np as a cancellation point (BZ#24215)Adhemerval Zanella
Patch ce7eb0e90315 ("nptl: Cleanup cancellation macros") changed the join sequence for internal common __pthread_timedjoin_ex to use the new macro lll_wait_tid. The idea was this macro would issue the cancellable futex operation depending whether the timeout is used or not. However if a timeout is used, __lll_timedwait_tid is called and it is not a cancellable entrypoint. This patch fixes it by simplifying the code in various ways: - Instead of adding the cancellation handling on __lll_timedwait_tid, it moves the generic implementation to pthread_join_common.c (called now timedwait_tid with some fixes to use the correct type for pid). - The llvm_wait_tid macro is removed, along with its replication on x86_64, i686, and sparc arch-specific lowlevellock.h. - sparc32 __lll_timedwait_tid is also removed, since the code is similar to generic one. - x86_64 and i386 provides arch-specific __lll_timedwait_tid which is also removed since they are similar in functionality to generic C code and there is no indication it is better than compiler generated code. New tests, tst-join8 and tst-join9, are provided to check if pthread_timedjoin_np acts as a cancellation point. Checked on x86_64-linux-gnu, i686-linux-gnu, sparcv9-linux-gnu, and aarch64-linux-gnu. [BZ #24215] * nptl/Makefile (lpthread-routines): Remove lll_timedwait_tid. (tests): Add tst-join8 tst-join9. * nptl/lll_timedwait_tid.c: Remove file. * sysdeps/sparc/sparc32/lll_timedwait_tid.c: Likewise. * sysdeps/unix/sysv/linux/i386/lll_timedwait_tid.c: Likewise. * sysdeps/sysv/linux/x86_64/lll_timedwait_tid.c: Likewise. * nptl/pthread_join_common.c (timedwait_tid): New function. (__pthread_timedjoin_ex): Act as cancellation entrypoint is block is set. * nptl/tst-join5.c (thread_join): New function. (tf1, tf2, do_test): Use libsupport and add pthread_timedjoin_np check. * nptl/tst-join8.c: New file. * nptl/tst-join9.c: Likewise. * sysdeps/nptl/lowlevellock-futex.h (lll_futex_wait_cancel, lll_futex_timed_wait_cancel): Add generic macros. * sysdeps/nptl/lowlevellock.h (__lll_timedwait_tid, lll_wait_tid): Remove definitions. * sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise. * sysdeps/unix/sysv/linux/sparc/lowlevellock.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Likewise. * sysdeps/sparc/sparc32/lowlevellock.c (__lll_timedwait_tid): Remove function. * sysdeps/unix/sysv/linux/i386/lowlevellock.S (__lll_timedwait_tid): Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/lowlevellock-futex.h (lll_futex_timed_wait_cancel): New macro.
2019-02-13RISC-V: Fix elfutils testsuite unwind failures.Jim Wilson
The clone.S patch fixes 2 elfutils testsuite unwind failures, where the backtrace gets stuck repeating __thread_start until we hit the backtrace limit. This was confirmed by building and installing a patched glibc and then building elfutils and running its testsuite. Unfortunately, the testcase isn't working as expected and I don't know why. The testcase passes even when my clone.S patch is not installed. The testcase looks logically similarly to the elfutils testcases that are failing. Maybe there is a subtle difference in how the glibc unwinding works versus the elfutils unwinding? I don't have good gdb pthread support yet, so I haven't found a way to debug this. Anyways, I don't know if the testcase is useful or not. If the testcase isn't useful then maybe the clone.S patch is OK without a testcase? Jim [BZ #24040] * elf/Makefile (CFLAGS-tst-unwind-main.c): Add -DUSE_PTHREADS=0. * elf/tst-unwind-main.c: If USE_PTHEADS, include pthread.h and error.h (func): New. (main): If USE_PTHREADS, call pthread_create to run func. Otherwise call func directly. * nptl/Makefile (tests): Add tst-unwind-thread. (CFLAGS-tst-unwind-thread.c): Define. * nptl/tst-unwind-thread.c: New file. * sysdeps/unix/sysv/linux/riscv/clone.S (__thread_start): Mark ra as undefined.
2019-02-08nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161]Florian Weimer
Commit 27761a1042daf01987e7d79636d0c41511c6df3c ("Refactor atfork handlers") introduced a lock, atfork_lock, around fork handler list accesses. It turns out that this lock occasionally results in self-deadlocks in malloc/tst-mallocfork2: (gdb) bt #0 __lll_lock_wait_private () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:63 #1 0x00007f160c6f927a in __run_fork_handlers (who=(unknown: 209394016), who@entry=atfork_run_prepare) at register-atfork.c:116 #2 0x00007f160c6b7897 in __libc_fork () at ../sysdeps/nptl/fork.c:58 #3 0x00000000004027d6 in sigusr1_handler (signo=<optimized out>) at tst-mallocfork2.c:80 #4 sigusr1_handler (signo=<optimized out>) at tst-mallocfork2.c:64 #5 <signal handler called> #6 0x00007f160c6f92e4 in __run_fork_handlers (who=who@entry=atfork_run_parent) at register-atfork.c:136 #7 0x00007f160c6b79a2 in __libc_fork () at ../sysdeps/nptl/fork.c:152 #8 0x0000000000402567 in do_test () at tst-mallocfork2.c:156 #9 0x0000000000402dd2 in support_test_main (argc=1, argv=0x7ffc81ef1ab0, config=config@entry=0x7ffc81ef1970) at support_test_main.c:350 #10 0x0000000000402362 in main (argc=<optimized out>, argv=<optimized out>) at ../support/test-driver.c:168 If no locking happens in the single-threaded case (where fork is expected to be async-signal-safe), this deadlock is avoided. (pthread_atfork is not required to be async-signal-safe, so a fork call from a signal handler interrupting pthread_atfork is not a problem.)
2019-02-07Add compiler barriers around modifications of the robust mutex list for ↵Stefan Liebler
pthread_mutex_trylock. [BZ #24180] While debugging a kernel warning, Thomas Gleixner, Sebastian Sewior and Heiko Carstens found a bug in pthread_mutex_trylock due to misordered instructions: 140: a5 1b 00 01 oill %r1,1 144: e5 48 a0 f0 00 00 mvghi 240(%r10),0 <--- THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); 14a: e3 10 a0 e0 00 24 stg %r1,224(%r10) <--- last THREAD_SETMEM of ENQUEUE_MUTEX_PI vs (with compiler barriers): 140: a5 1b 00 01 oill %r1,1 144: e3 10 a0 e0 00 24 stg %r1,224(%r10) 14a: e5 48 a0 f0 00 00 mvghi 240(%r10),0 Please have a look at the discussion: "Re: WARN_ON_ONCE(!new_owner) within wake_futex_pi() triggerede" (https://lore.kernel.org/lkml/20190202112006.GB3381@osiris/) This patch is introducing the same compiler barriers and comments for pthread_mutex_trylock as introduced for pthread_mutex_lock and pthread_mutex_timedlock by commit 8f9450a0b7a9e78267e8ae1ab1000ebca08e473e "Add compiler barriers around modifications of the robust mutex list." ChangeLog: [BZ #24180] * nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock):
2019-02-06Avoid "inline" after return type in function definitions.Joseph Myers
One group of warnings seen with -Wextra is warnings for static or inline not at the start of a declaration (-Wold-style-declaration). This patch fixes various such cases for inline, ensuring it comes at the start of the declaration (after any static). A common case of the fix is "static inline <type> __always_inline"; the definition of __always_inline starts with __inline, so the natural change is to "static __always_inline <type>". Other cases of the warning may be harder to fix (one pattern is a function definition that gets rewritten to be static by an including file, "#define funcname static wrapped_funcname" or similar), but it seems worth fixing these cases with inline anyway. Tested for x86_64. * elf/dl-load.h (_dl_postprocess_loadcmd): Use __always_inline before return type, without separate inline. * elf/dl-tunables.c (maybe_enable_malloc_check): Likewise. * elf/dl-tunables.h (tunable_is_name): Likewise. * malloc/malloc.c (do_set_trim_threshold): Likewise. (do_set_top_pad): Likewise. (do_set_mmap_threshold): Likewise. (do_set_mmaps_max): Likewise. (do_set_mallopt_check): Likewise. (do_set_perturb_byte): Likewise. (do_set_arena_test): Likewise. (do_set_arena_max): Likewise. (do_set_tcache_max): Likewise. (do_set_tcache_count): Likewise. (do_set_tcache_unsorted_limit): Likewise. * nis/nis_subr.c (count_dots): Likewise. * nptl/allocatestack.c (advise_stack_range): Likewise. * sysdeps/ieee754/dbl-64/s_sin.c (do_cos): Likewise. (do_sin): Likewise. (reduce_sincos): Likewise. (do_sincos): Likewise. * sysdeps/unix/sysv/linux/x86/elision-conf.c (do_set_elision_enable): Likewise. (TUNABLE_CALLBACK_FNDECL): Likewise.
2019-02-06Fix alignment of TLS variables for tls variant TLS_TCB_AT_TP [BZ #23403]Stefan Liebler
The alignment of TLS variables is wrong if accessed from within a thread for architectures with tls variant TLS_TCB_AT_TP. For the main thread the static tls data is properly aligned. For other threads the alignment depends on the alignment of the thread pointer as the static tls data is located relative to this pointer. This patch adds this alignment for TLS_TCB_AT_TP variants in the same way as it is already done for TLS_DTV_AT_TP. The thread pointer is also already properly aligned if the user provides its own stack for the new thread. This patch extends the testcase nptl/tst-tls1.c in order to check the alignment of the tls variables and it adds a pthread_create invocation with a user provided stack. The test itself is migrated from test-skeleton.c to test-driver.c and the missing support functions xpthread_attr_setstack and xposix_memalign are added. ChangeLog: [BZ #23403] * nptl/allocatestack.c (allocate_stack): Align pointer pd for TLS_TCB_AT_TP tls variant. * nptl/tst-tls1.c: Migrate to support/test-driver.c. Add alignment checks. * support/Makefile (libsupport-routines): Add xposix_memalign and xpthread_setstack. * support/support.h: Add xposix_memalign. * support/xthread.h: Add xpthread_attr_setstack. * support/xposix_memalign.c: New File. * support/xpthread_attr_setstack.c: Likewise.
2019-01-31nptl: Fix pthread_rwlock_try*lock stalls (Bug 23844)Carlos O'Donell
For a full analysis of both the pthread_rwlock_tryrdlock() stall and the pthread_rwlock_trywrlock() stall see: https://sourceware.org/bugzilla/show_bug.cgi?id=23844#c14 In the pthread_rwlock_trydlock() function we fail to inspect for PTHREAD_RWLOCK_FUTEX_USED in __wrphase_futex and wake the waiting readers. In the pthread_rwlock_trywrlock() function we write 1 to __wrphase_futex and loose the setting of the PTHREAD_RWLOCK_FUTEX_USED bit, again failing to wake waiting readers during unlock. The fix in the case of pthread_rwlock_trydlock() is to check for PTHREAD_RWLOCK_FUTEX_USED and wake the readers. The fix in the case of pthread_rwlock_trywrlock() is to only write 1 to __wrphase_futex if we installed the write phase, since all other readers would be spinning waiting for this step. We add two new tests, one exercises the stall for pthread_rwlock_trywrlock() which is easy to exercise, and one exercises the stall for pthread_rwlock_trydlock() which is harder to exercise. The pthread_rwlock_trywrlock() test fails consistently without the fix, and passes after. The pthread_rwlock_tryrdlock() test fails roughly 5-10% of the time without the fix, and passes all the time after. Signed-off-by: Carlos O'Donell <carlos@redhat.com> Signed-off-by: Torvald Riegel <triegel@redhat.com> Signed-off-by: Rik Prohaska <prohaska7@gmail.com> Co-authored-by: Torvald Riegel <triegel@redhat.com> Co-authored-by: Rik Prohaska <prohaska7@gmail.com>
2019-01-03nptl: Cleanup cancellation macrosAdhemerval Zanella
This patch wraps all uses of *_{enable,disable}_asynccancel and and *_CANCEL_{ASYNC,RESET} in either already provided macros (lll_futex_timed_wait_cancel) or creates new ones if the functionality is not provided (SYSCALL_CANCEL_NCS, lll_futex_wait_cancel, and lll_futex_timed_wait_cancel). Also for some generic implementations, the direct call of the macros are removed since the underlying symbols are suppose to provide cancellation support. This is a priliminary patch intended to simplify the work required for BZ#12683 fix. It is a refactor change, no semantic changes are expected. Checked on x86_64-linux-gnu and i686-linux-gnu. * nptl/pthread_join_common.c (__pthread_timedjoin_ex): Use lll_wait_tid with timeout. * nptl/sem_wait.c (__old_sem_wait): Use lll_futex_wait_cancel. * sysdeps/nptl/aio_misc.h (AIO_MISC_WAIT): Use futex_reltimed_wait_cancelable for cancelabla mode. * sysdeps/nptl/gai_misc.h (GAI_MISC_WAIT): Likewise. * sysdeps/posix/open64.c (__libc_open64): Do not call cancelation macros. * sysdeps/posix/sigwait.c (__sigwait): Likewise. * sysdeps/posix/waitid.c (__sigwait): Likewise. * sysdeps/unix/sysdep.h (__SYSCALL_CANCEL_CALL, SYSCALL_CANCEL_NCS): New macro. * sysdeps/nptl/lowlevellock.h (lll_wait_tid): Add timeout argument. (lll_timedwait_tid): Remove macro. * sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_wait_tid): Likewise. (lll_timedwait_tid): Likewise. * sysdeps/unix/sysv/linux/sparc/lowlevellock.h (lll_wait_tid): Likewise. (lll_timedwait_tid): Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (lll_wait_tid): Likewise. (lll_timedwait_tid): Likewise. * sysdeps/unix/sysv/linux/clock_nanosleep.c (__clock_nanosleep): Use INTERNAL_SYSCALL_CANCEL. * sysdeps/unix/sysv/linux/futex-internal.h (futex_reltimed_wait_cancelable): Use LIBC_CANCEL_{ASYNC,RESET} instead of __pthread_{enable,disable}_asynccancel. * sysdeps/unix/sysv/linux/lowlevellock-futex.h (lll_futex_wait_cancel): New macro.
2019-01-03nptl: Fix testcases for new pthread cancellation mechanismAdhemerval Zanella
With upcoming fix for BZ#12683, pthread cancellation does not act for: 1. If syscall is blocked but with some side effects already having taken place (e.g. a partial read or write). 2. After the syscall has returned. The main change is due the fact programs need to act in syscalls with side-effects (for instance, to avoid leak of allocated resources or handle partial read/write). This patch changes the NPTL testcase that assumes the old behavior and also changes the tst-backtrace{5,6} to ignore the cancellable wrappers. Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32, aarch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc-linux-gnu, sparcv9-linux-gnu, and sparc64-linux-gnu. * debug/tst-backtrace5.c (handle_signal): Avoid cancellable wrappers in backtrace analysis. * nptl/tst-cancel4.c (tf_write): Handle cancelled syscall with side-effects. (tf_send): Likewise.
2019-01-03nptl: Remove tst-cancel-wrappers test and related macrosAdhemerval Zanella
With upcoming BZ#12683 fix, syscall cancellation is not more handled by {libc,pthread,librt}_{enable,disable}_asynccancel symbols. This renders both LIBC_CANCEL_HANDLED and empty declaration and tst-cancel-wrappers.sh unrequired. This patch removes both the macro and the nptl test. Checked on x86_64-linux-gnu. * io/creat.c (LIBC_CANCEL_HANDLED): Remove macro. * io/ppoll.c (LIBC_CANCEL_HANDLED): Likewise. * misc/pselect.c (LIBC_CANCEL_HANDLED): Likewise. * nptl/pthreadP.h (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/generic/sysdep-cancel.h (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/mach/hurd/sysdep-cancel.h (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/posix/pause.c (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/posix/sigpause.c (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/unix/sysv/linux/creat.c (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/unix/sysv/linux/creat64.c (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/unix/sysv/linux/sigwait.c (LIBC_CANCEL_HANDLED): Likewise. * sysdeps/unix/sysv/linux/sigwaitinfo.c (LIBC_CANCEL_HANDLED): Likewise. * nptl/Makefile [$(run-built-tests) = yes] (tests-special): Remove tst-cancel-wrappers.sh. (generated): Remove tst-cancel-wrappers.out. (tst-cancel-wrappers.out): Remove rule. * nptl/tst-cancel-wrappers.sh: Remove file.
2019-01-02nptl/tst-audit-threads: Switch to <support/test-driver.c>Florian Weimer
This is a new test, so it should use the test driver in the support subdirectory.
2019-01-01Update copyright dates not handled by scripts/update-copyrights.Joseph Myers
I've updated copyright dates in glibc for 2019. This is the patch for the changes not generated by scripts/update-copyrights and subsequent build / regeneration of generated files. Please remember to include 2019 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). * NEWS: Update copyright dates. * catgets/gencat.c (print_version): Likewise. * csu/version.c (banner): Likewise. * debug/catchsegv.sh: Likewise. * debug/pcprofiledump.c (print_version): Likewise. * debug/xtrace.sh (do_version): Likewise. * elf/ldconfig.c (print_version): Likewise. * elf/ldd.bash.in: Likewise. * elf/pldd.c (print_version): Likewise. * elf/sotruss.sh: Likewise. * elf/sprof.c (print_version): Likewise. * iconv/iconv_prog.c (print_version): Likewise. * iconv/iconvconfig.c (print_version): Likewise. * locale/programs/locale.c (print_version): Likewise. * locale/programs/localedef.c (print_version): Likewise. * login/programs/pt_chown.c (print_version): Likewise. * malloc/memusage.sh (do_version): Likewise. * malloc/memusagestat.c (print_version): Likewise. * malloc/mtrace.pl: Likewise. * manual/libc.texinfo: Likewise. * nptl/version.c (banner): Likewise. * nscd/nscd.c (print_version): Likewise. * nss/getent.c (print_version): Likewise. * nss/makedb.c (print_version): Likewise. * posix/getconf.c (main): Likewise. * scripts/test-installation.pl: Likewise. * sysdeps/unix/sysv/linux/lddlibc4.c (main): Likewise.
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-12-13Fix rwlock stall with PREFER_WRITER_NONRECURSIVE_NP (bug 23861)Andreas Schwab
In the read lock function (__pthread_rwlock_rdlock_full) there was a code path which would fail to reload __readers while waiting for PTHREAD_RWLOCK_RWAITING to change. This failure to reload __readers into a local value meant that various conditionals used the old value of __readers and with only two threads left it could result in an indefinite stall of one of the readers (waiting for PTHREAD_RWLOCK_RWAITING to go to zero, but it never would).
2018-12-13Reindent nptl/pthread_rwlock_common.cAndreas Schwab
2018-12-10Use gen-as-const.py to process .pysym files.Joseph Myers
This patch eliminates the gen-py-const.awk variant of gen-as-const, switching to use of gnu-as-const.py (with a new --python option) to process .pysym files (i.e., to generate nptl_lock_constants.py), as the syntax of those files is identical to that of .sym files. Note that the generated nptl_lock_constants.py is *not* identical to the version generated by the awk script. Apart from the trivial changes (comment referencing the new script, and output being sorted), the constant FUTEX_WAITERS, PTHREAD_MUTEXATTR_FLAG_BITS, PTHREAD_MUTEXATTR_FLAG_PSHARED and PTHREAD_MUTEX_PRIO_CEILING_MASK are now output as positive rather than negative constants (on x86_64 anyway; maybe not necessarily on 32-bit systems): < FUTEX_WAITERS = -2147483648 --- > FUTEX_WAITERS = 2147483648 < PTHREAD_MUTEXATTR_FLAG_BITS = -251662336 < PTHREAD_MUTEXATTR_FLAG_PSHARED = -2147483648 --- > PTHREAD_MUTEXATTR_FLAG_BITS = 4043304960 > PTHREAD_MUTEXATTR_FLAG_PSHARED = 2147483648 < PTHREAD_MUTEX_PRIO_CEILING_MASK = -524288 --- > PTHREAD_MUTEX_PRIO_CEILING_MASK = 4294443008 This is because gen-as-const has a cast of the constant value to long int, which gen-py-const lacks. I think the positive values are more logically correct, since the constants in question are in fact unsigned in C. But to reliably produce gen-as-const.py output for constants that always (in C and Python) reflects the signedness of values with the high bit of "long int" set would mean more complicated logic needs to be used in computing values. The more correct positive values by themselves produce a failure of nptl/test-mutexattr-printers, because masking with ~PTHREAD_MUTEXATTR_FLAG_BITS & ~PTHREAD_MUTEX_NO_ELISION_NP now leaves a bit -1 << 32 in the Python value, resulting in a KeyError exception. To avoid that, places masking with ~ of one of the constants in question are changed to mask with 0xffffffff as well (this reflects how ~ in Python applies to an infinite-precision integer whereas ~ in C does not do any promotions beyond the width of int). Tested for x86_64. * scripts/gen-as-const.py (main): Handle --python option. * scripts/gen-py-const.awk: Remove. * Makerules (py-const-script): Use gen-as-const.py. ($(py-const)): Likewise. * nptl/nptl-printers.py (MutexPrinter.read_status_no_robust): Mask with 0xffffffff together with ~(PTHREAD_MUTEX_PRIO_CEILING_MASK). (MutexAttributesPrinter.read_values): Mask with 0xffffffff together with ~PTHREAD_MUTEXATTR_FLAG_BITS and ~PTHREAD_MUTEX_NO_ELISION_NP. * manual/README.pretty-printers: Update reference to gen-py-const.awk.
2018-12-01Mutex: Add pthread mutex tunablesKemi Wang
This patch does not have any functionality change, we only provide a spin count tunes for pthread adaptive spin mutex. The tunable glibc.pthread.mutex_spin_count tunes can be used by system administrator to squeeze system performance according to different hardware capabilities and workload characteristics. The maximum value of spin count is limited to 32767 to avoid the overflow of mutex->__data.__spins variable with the possible type of short in pthread_mutex_lock (). The default value of spin count is set to 100 with the reference to the previous number of times of spinning via trylock. This value would be architecture-specific and can be tuned with kinds of benchmarks to fit most cases in future. I would extend my appreciation sincerely to H.J.Lu for his help to refine this patch series. * manual/tunables.texi (POSIX Thread Tunables): New node. * nptl/Makefile (libpthread-routines): Add pthread_mutex_conf. * nptl/nptl-init.c: Include pthread_mutex_conf.h (__pthread_initialize_minimal_internal) [HAVE_TUNABLES]: Call __pthread_tunables_init. * nptl/pthreadP.h (MAX_ADAPTIVE_COUNT): Remove. (max_adaptive_count): Define. * nptl/pthread_mutex_conf.c: New file. * nptl/pthread_mutex_conf.h: New file. * sysdeps/generic/adaptive_spin_count.h: New file. * sysdeps/nptl/dl-tunables.list: New file. * nptl/pthread_mutex_lock.c (__pthread_mutex_lock): Use max_adaptive_count () not MAX_ADAPTIVE_COUNT. * nptl/pthread_mutex_timedlock.c (__pthrad_mutex_timedlock): Likewise. Suggested-by: Andi Kleen <andi.kleen@intel.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com> Signed-off-by: Kemi.wang <kemi.wang@intel.com>
2018-11-30Fix _dl_profile_fixup data-dependency issue (Bug 23690)Tulio Magno Quites Machado Filho
There is a data-dependency between the fields of struct l_reloc_result and the field used as the initialization guard. Users of the guard expect writes to the structure to be observable when they also observe the guard initialized. The solution for this problem is to use an acquire and release load and store to ensure previous writes to the structure are observable if the guard is initialized. The previous implementation used DL_FIXUP_VALUE_ADDR (l_reloc_result->addr) as the initialization guard, making it impossible for some architectures to load and store it atomically, i.e. hppa and ia64, due to its larger size. This commit adds an unsigned int to l_reloc_result to be used as the new initialization guard of the struct, making it possible to load and store it atomically in all architectures. The fix ensures that the values observed in l_reloc_result are consistent and do not lead to crashes. The algorithm is documented in the code in elf/dl-runtime.c (_dl_profile_fixup). Not all data races have been eliminated. Tested with build-many-glibcs and on powerpc, powerpc64, and powerpc64le. [BZ #23690] * elf/dl-runtime.c (_dl_profile_fixup): Guarantee memory modification order when accessing reloc_result->addr. * include/link.h (reloc_result): Add field init. * nptl/Makefile (tests): Add tst-audit-threads. (modules-names): Add tst-audit-threads-mod1 and tst-audit-threads-mod2. Add rules to build tst-audit-threads. * nptl/tst-audit-threads-mod1.c: New file. * nptl/tst-audit-threads-mod2.c: Likewise. * nptl/tst-audit-threads.c: Likewise. * nptl/tst-audit-threads.h: Likewise. Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-11-23Enable VDSO on x86_64 statically linked programs [BZ #19767]Rafael Ávila de Espíndola
All the required code already existed, and some of it was already running. AT_SYSINFO_EHDR is processed if NEED_DL_SYSINFO_DSO is defined, but it looks like it always is. The call to setup_vdso is also unconditional, so all that was left to do was setup the function pointers and use them. This patch just deletes some #ifdef to enable that. [BZ #19767] * nptl/Makefile (tests-static): Add tst-cond11-static. (tests): Likewise. * nptl/tst-cond11-static.c: New File. * sysdeps/unix/sysv/linux/Makefile (tests-static): Add tst-affinity-static. (tests): Likewise. * sysdeps/unix/sysv/linux/sysdep-vdso.h: Check USE_VSYSCALL instead of SHARED. * sysdeps/unix/sysv/linux/sysdep.h (ALWAYS_USE_VSYSCALL): New. (USE_VSYSCALL): Likewise. * sysdeps/unix/sysv/linux/tst-affinity-static.c: New file. * sysdeps/unix/sysv/linux/x86/libc-vdso.h: Check USE_VSYSCALL instead of SHARED. * sysdeps/unix/sysv/linux/x86_64/init-first.c: Don't check SHARED. * sysdeps/unix/sysv/linux/x86_64/sysdep.h (ALWAYS_USE_VSYSCALL): New.
2018-10-17Fix race in pthread_mutex_lock while promoting to PTHREAD_MUTEX_ELISION_NP ↵Stefan Liebler
[BZ #23275] The race leads either to pthread_mutex_destroy returning EBUSY or triggering an assertion (See description in bugzilla). This patch is fixing the race by ensuring that the elision path is used in all cases if elision is enabled by the GLIBC_TUNABLES framework. The __kind variable in struct __pthread_mutex_s is accessed concurrently. Therefore we are now using the atomic macros. The new testcase tst-mutex10 is triggering the race on s390x and intel. Presumably also on power, but I don't have access to a power machine with lock-elision. At least the code for power is the same as on the other two architectures. ChangeLog: [BZ #23275] * nptl/tst-mutex10.c: New File. * nptl/Makefile (tests): Add tst-mutex10. (tst-mutex10-ENV): New variable. * sysdeps/unix/sysv/linux/s390/force-elision.h: (FORCE_ELISION): Ensure that elision path is used if elision is available. * sysdeps/unix/sysv/linux/powerpc/force-elision.h (FORCE_ELISION): Likewise. * sysdeps/unix/sysv/linux/x86/force-elision.h: (FORCE_ELISION): Likewise. * nptl/pthreadP.h (PTHREAD_MUTEX_TYPE, PTHREAD_MUTEX_TYPE_ELISION) (PTHREAD_MUTEX_PSHARED): Use atomic_load_relaxed. * nptl/pthread_mutex_consistent.c (pthread_mutex_consistent): Likewise. * nptl/pthread_mutex_getprioceiling.c (pthread_mutex_getprioceiling): Likewise. * nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full) (__pthread_mutex_cond_lock_adjust): Likewise. * nptl/pthread_mutex_setprioceiling.c (pthread_mutex_setprioceiling): Likewise. * nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Likewise. * nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock): Likewise. * nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise. * sysdeps/nptl/bits/thread-shared-types.h (struct __pthread_mutex_s): Add comments. * nptl/pthread_mutex_destroy.c (__pthread_mutex_destroy): Use atomic_load_relaxed and atomic_store_relaxed. * nptl/pthread_mutex_init.c (__pthread_mutex_init): Use atomic_store_relaxed.
2018-10-17Don't reduce test timeout to less than defaultAndreas Schwab
This removes all overrides of TIMEOUT that are less than or equal to the default timeout.
2018-08-31[BZ #20271] Add newlines in __libc_fatal calls.Paul Pluzhnikov
2018-08-27pthread_cond_broadcast: Fix waiters-after-spinning case [BZ #23538]Martin Kuchta
2018-07-25Fix ISO C threads installed header and HURD assumptionAdhemerval Zanella
Set installed NPTL header as the expected one (instead of an internal one for glibc testsuite) and add a hurd specific stdc-predef with __STDC_NO_THREADS__. Checked on both i686-linux-gnu and i686-gnu that both threads.h and stdc-predef.h are the expected ones. * nptl/threads.h: Move to ... * sysdeps/nptl/threads.h: ... here. * sysdeps/hurd/stdc-predef.h: New file.
2018-07-25C11 threads: Fix timeout and locking issuesFlorian Weimer
2018-07-24nptl: Add test cases for ISO C11 threadsAdhemerval Zanella
This patch adds to testsuite new test cases to test all new introduced C11 threads functions, types and macros are tested. Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu, powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu, and x86_64-linux-gnu). Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabhf, and powerpc64le-linux-gnu. Adhemerval Zanella <adhemerval.zanella@linaro.org> Juan Manuel Torres Palma <jmtorrespalma@gmail.com> [BZ #14092] * nptl/Makefile (tests): Add new test files. * nptl/tst-call-once.c : New file. Tests C11 functions and types. * nptl/tst-cnd-basic.c: Likewise. * nptl/tst-cnd-broadcast.c: Likewise. * nptl/tst-cnd-timedwait.c: Likewise. * nptl/tst-mtx-basic.c: Likewise. * nptl/tst-mtx-recursive.c: Likewise. * nptl/tst-mtx-timedlock.c: Likewise. * nptl/tst-mtx-trylock.c: Likewise. * nptl/tst-thrd-basic.c: Likewise. * nptl/tst-thrd-detach.c: Likewise. * nptl/tst-thrd-sleep.c: Likewise. * nptl/tst-tss-basic.c: Likewise.
2018-07-24nptl: Add C11 threads tss_* functionsAdhemerval Zanella
This patch adds the tss_* definitions from C11 threads (ISO/IEC 9899:2011), more specifically tss_create, tss_delete, tss_get, tss_set, and required types. Mostly of the definitions are composed based on POSIX conterparts, including tss_t (pthread_key_t). Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu, powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu, and x86_64-linux-gnu). Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabhf, and powerpc64le-linux-gnu. [BZ #14092] * conform/data/threads.h-data (thread_local): New macro. (TSS_DTOR_ITERATIONS): Likewise. (tss_t): New type. (tss_dtor_t): Likewise. (tss_create): New function. (tss_get): Likewise. (tss_set): Likewise. (tss_delete): Likewise. * nptl/Makefile (libpthread-routines): Add tss_create, tss_delete, tss_get, and tss_set objects. * nptl/Versions (libpthread) [GLIBC_2.28]: Likewise. * nptl/tss_create.c: New file. * nptl/tss_delete.c: Likewise. * nptl/tss_get.c: Likewise. * nptl/tss_set.c: Likewise. * sysdeps/nptl/threads.h (thread_local): New define. (TSS_DTOR_ITERATIONS): Likewise. (tss_t): New typedef. (tss_dtor_t): Likewise. (tss_create): New prototype. (tss_get): Likewise. (tss_set): Likewise. (tss_delete): Likewise.
2018-07-24nptl: Add C11 threads cnd_* functionsAdhemerval Zanella
This patch adds the cnd_* definitions from C11 threads (ISO/IEC 9899:2011), more specifically cnd_broadcast, cnd_destroy, cnd_init, cnd_signal, cnd_timedwait, cnd_wait, and required types. Mostly of the definitions are composed based on POSIX conterparts, and cnd_t is also based on internal pthreads fields, but with distinct internal layout to avoid possible issues with code interchange (such as trying to pass POSIX structure on C11 functions and to avoid inclusion of pthread.h). The idea is to make it possible to share POSIX internal implementation for mostly of the code making adjust where only required. Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu, powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu, and x86_64-linux-gnu). Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabhf, and powerpc64le-linux-gnu. [BZ #14092] * conform/data/threads.h-data (cnd_t): New type. (cnd_init): New function. (cnd_signal): Likewise. (cnd_broadcast): Likewise. (cnd_wait): Likewise. (cnd_timedwait): Likewise. (cnd_destroy): Likewise. * nptl/Makefile (libpthread-routines): Add cnd_broadcast, cnd_destroy, cnd_init, cnd_signal, cnd_timedwait, and cnd_wait object. * nptl/Versions (libpthread) [GLIBC_2.28]: Likewise. * nptl/cnd_broadcast.c: New file. * nptl/cnd_destroy.c: Likewise. * nptl/cnd_init.c: Likewise. * nptl/cnd_signal.c: Likewise. * nptl/cnd_timedwait.c: Likewise. * nptl/cnd_wait.c: Likewise. * sysdeps/nptl/threads.h (cnd_t): New type. (cnd_init): New prototype. (cnd_signa): Likewise. (cnd_broadcast): Likewise. (cnd_wait): Likewise. (cnd_timedwait): Likewise. (cnd_destroy): Likewise.
2018-07-24nptl: Add C11 threads call_once functionsAdhemerval Zanella
This patch adds the call_* definitions from C11 threads (ISO/IEC 9899:2011), more specifically call_once and required types. Mostly of the definitions are composed based on POSIX conterparts,including once_flag (pthread_once_t). The idea is to make possible to share POSIX internal implementations for mostly of the code (and making adjustment only when required). Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu, powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu, and x86_64-linux-gnu). Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabhf, and powerpc64le-linux-gnu. [BZ #14092] * conform/data/threads.h-data (ONCE_FLAG_INIT): New macro. (once_flag): New type. (call_once): New function. * nptl/Makefile (libpthread-routines): Add call_once object. * nptl/Versions (libphread) [GLIBC_2.28]: Add call_once symbol. * nptl/call_once.c: New file. * sysdeps/nptl/threads.h (ONCE_FLAG_INIT): New define. (once_flag): New type. (call_once): New prototype.
2018-07-24nptl: Add C11 threads mtx_* functionsAdhemerval Zanella
This patch adds the mtx_* definitions from C11 threads (ISO/IEC 9899:2011), more specifically mtx_init, mtx_destroy, mtx_lock, mtx_timedlock, mtx_trylock, mtx_unlock, and required types. Mostly of the definitions are composed based on POSIX conterparts, and mtx_t is also based on internal pthread fields, but with a distinct internal layout to avoid possible issues with code interchange (such as trying to pass POSIX structure on C11 functions and to avoid inclusion of pthread.h). The idea is to make possible to share POSIX internal implementations for mostly of the code (and making adjustment only when required). Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu, powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu, and x86_64-linux-gnu). Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabhf, and powerpc64le-linux-gnu. [BZ #14092] * conform/data/threads.h-data (mtx_plain): New constant. (mtx_recursive): Likewise. (mtx_timed): Likewise. (mtx_t): New type. (mtx_init): New function. (mtx_lock): Likewise. (mtx_timedlock): Likewise. (mtx_trylock): Likewise. (mtx_unlock): Likewise. (mtx_destroy): Likewise. * nptl/Makefile (libpthread-routines): Add mtx_destroy, mtx_init, mtx_lock, mtx_timedlock, mtx_trylock, and mtx_unlock object. * nptl/Versions (libpthread) [GLIBC_2.28]): Add mtx_init, mtx_lock, mtx_timedlock, mtx_trylock, mtx_unlock, and mtx_destroy. * nptl/mtx_destroy.c: New file. * nptl/mtx_init.c: Likewise. * nptl/mtx_lock.c: Likewise. * nptl/mtx_timedlock.c: Likewise. * nptl/mtx_trylock.c: Likewise. * nptl/mtx_unlock.c: Likewise. * sysdeps/nptl/threads.h (mtx_plain): New enumeration. (mtx_recursive): Likewise. (mtx_timed): Likewise. (mtx_t): New type. (mtx_init): New prototype. (mtx_lock): Likewise. (mtx_timedlock): Likewise. (mtx_trylock): Likewise. (mtx_unlock): Likewise. (mtx_destroy): Likewise.
2018-07-24nptl: Add C11 threads thrd_* functionsAdhemerval Zanella
This patch adds the thrd_* definitions from C11 threads (ISO/IEC 9899:2011), more specifically thrd_create, thrd_curent, rhd_detach, thrd_equal, thrd_exit, thrd_join, thrd_sleep, thrd_yield, and required types. Mostly of the definitions are composed based on POSIX conterparts, such as thrd_t (using pthread_t). For thrd_* function internally direct POSIX pthread call are used with the exceptions: 1. thrd_start uses pthread_create internal implementation, but changes how to actually calls the start routine. This is due the difference in signature between POSIX and C11, where former return a 'void *' and latter 'int'. To avoid calling convention issues due 'void *' to int cast, routines from C11 threads are started slight different than default pthread one. Explicit cast to expected return are used internally on pthread_create and the result is stored back to void also with an explicit cast. 2. thrd_sleep uses nanosleep internal direct syscall to avoid clobbering errno and to handle expected standard return codes. It is a cancellation entrypoint to be consistent with both thrd_join and cnd_{timed}wait. 3. thrd_yield also uses internal direct syscall to avoid errno clobbering. Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu, powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu, and x86_64-linux-gnu). Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabhf, and powerpc64le-linux-gnu. [BZ #14092] * conform/Makefile (conformtest-headers-ISO11): Add threads.h. (linknamespace-libs-ISO11): Add libpthread.a. * conform/data/threads.h-data: New file: add C11 thrd_* types and functions. * include/stdc-predef.h (__STDC_NO_THREADS__): Remove definition. * nptl/Makefile (headers): Add threads.h. (libpthread-routines): Add new C11 thread thrd_create, thrd_current, thrd_detach, thrd_equal, thrd_exit, thrd_join, thrd_sleep, and thrd_yield. * nptl/Versions (libpthread) [GLIBC_2.28]): Add new C11 thread thrd_create, thrd_current, thrd_detach, thrd_equal, thrd_exit, thrd_join, thrd_sleep, and thrd_yield symbols. * nptl/descr.h (struct pthread): Add c11 field. * nptl/pthreadP.h (ATTR_C11_THREAD): New define. * nptl/pthread_create.c (START_THREAD_DEFN): Call C11 thread start routine with expected function prototype. (__pthread_create_2_1): Add C11 threads check based on attribute value. * sysdeps/unix/sysdep.h (INTERNAL_SYSCALL_CANCEL): New macro. * nptl/thrd_create.c: New file. * nptl/thrd_current.c: Likewise. * nptl/thrd_detach.c: Likewise. * nptl/thrd_equal.c: Likewise. * nptl/thrd_exit.c: Likewise. * nptl/thrd_join.c: Likewise. * nptl/thrd_priv.h: Likewise. * nptl/thrd_sleep.c: Likewise. * nptl/thrd_yield.c: Likewise. * include/threads.h: Likewise.
2018-07-14x86: Rename __glibc_reserved1 to feature_1 in tcbhead_t [BZ #22563]H.J. Lu
feature_1 has X86_FEATURE_1_IBT and X86_FEATURE_1_SHSTK bits for CET run-time control. CET_ENABLED, IBT_ENABLED and SHSTK_ENABLED are defined to 1 or 0 to indicate that if CET, IBT and SHSTK are enabled. <tls-setup.h> is added to set up thread-local data. Reviewed-by: Carlos O'Donell <carlos@redhat.com> [BZ #22563] * nptl/pthread_create.c: Include <tls-setup.h>. (__pthread_create_2_1): Call tls_setup_tcbhead. * sysdeps/generic/tls-setup.h: New file. * sysdeps/x86/nptl/tls-setup.h: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): Likewise. * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 to feature_1. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/x86/sysdep.h (X86_FEATURE_1_IBT): New. (X86_FEATURE_1_SHSTK): Likewise. (CET_ENABLED): Likewise. (IBT_ENABLED): Likewise. (SHSTK_ENABLED): Likewise.
2018-07-12nptl: Use __mprotect consistently for _STACK_GROWS_UPFlorian Weimer
2018-06-29libc: Extend __libc_freeres framework (Bug 23329).Carlos O'Donell
The __libc_freeres framework does not extend to non-libc.so objects. This causes problems in general for valgrind and mtrace detecting unfreed objects in both libdl.so and libpthread.so. This change is a pre-requisite to properly moving the malloc hooks out of malloc since such a move now requires precise accounting of all allocated data before destructors are run. This commit adds a proper hook in libc.so.6 for both libdl.so and for libpthread.so, this ensures that shm-directory.c which uses freeit () to free memory is called properly. We also remove the nptl_freeres hook and fall back to using weak-ref-and-check idiom for a loaded libpthread.so, thus making this process similar for all DSOs. Lastly we follow best practice and use explicit free calls for both libdl.so and libpthread.so instead of the generic hook process which has undefined order. Tested on x86_64 with no regressions. Signed-off-by: DJ Delorie <dj@redhat.com> Signed-off-by: Carlos O'Donell <carlos@redhat.com>
2018-06-27Remove nptl/sockperf.c.Joseph Myers
This patch removes nptl/sockperf.c, an unused, x86-specific program with a hardcoded path in /tmp. If someone finds some of this code in future for adding a proper benchmark, that does not of course rule out adding it back in that form, but for now I think it's best to eliminate this code with the hardcoded /tmp path. Tested for x86_64. * nptl/sockperf.c: Remove file.
2018-06-26In sem_open.c, pad was not initialized when __HAVE_64B_ATOMICS wasPatsy Franklin
true. On some arches this caused valgrind to warn about uninitialized bytes when the struct was written to the file system. This patch moves the initialization of pad outside of the conditional. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-06-26Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251)Adhemerval Zanella
This patch fixes the OFD ("file private") locks for architectures that support non-LFS flock definition (__USE_FILE_OFFSET64 not defined). The issue in this case is both F_OFD_{GETLK,SETLK,SETLKW} and F_{SET,GET}L{W}K64 expects a flock64 argument and when using old F_OFD_* flags with a non LFS flock argument the kernel might interpret the underlying data wrongly. Kernel idea originally was to avoid using such flags in non-LFS syscall, but since GLIBC uses fcntl with LFS semantic as default it is possible to provide the functionality and avoid the bogus struct kernel passing by adjusting the struct manually for the required flags. The idea follows other LFS interfaces that provide two symbols: 1. A new LFS fcntl64 is added on default ABI with the usual macros to select it for FILE_OFFSET_BITS=64. 2. The Linux non-LFS fcntl use a stack allocated struct flock64 for F_OFD_{GETLK,SETLK,SETLKW} copy the results on the user provided struct. 3. Keep a compat symbol with old broken semantic for architectures that do not define __OFF_T_MATCHES_OFF64_T. So for architectures which defines __USE_FILE_OFFSET64, fcntl64 will aliased to fcntl and no adjustment would be required. So to actually use F_OFD_* with LFS support the source must be built with LFS support (_FILE_OFFSET_BITS=64). Also F_OFD_SETLKW command is handled a cancellation point, as for F_SETLKW{64}. Checked on x86_64-linux-gnu and i686-linux-gnu. [BZ #20251] * NEWS: Mention fcntl64 addition. * csu/check_fds.c: Replace __fcntl_nocancel by __fcntl64_nocancel. * login/utmp_file.c: Likewise. * sysdeps/posix/fdopendir.c: Likewise. * sysdeps/posix/opendir.c: Likewise. * sysdeps/unix/pt-fcntl.c: Likewise. * include/fcntl.h (__libc_fcntl64, __fcntl64, __fcntl64_nocancel_adjusted): New prototype. (__fcntl_nocancel_adjusted): Remove prototype. * io/Makefile (routines): Add fcntl64. (CFLAGS-fcntl64.c): New rule. * io/Versions [GLIBC_2.28] (fcntl64): New symbol. [GLIBC_PRIVATE] (__libc_fcntl): Rename to __libc_fcntl64. * io/fcntl.h (fcntl64): Add prototype and redirect if __USE_FILE_OFFSET64 is defined. * io/fcntl64.c: New file. * manual/llio.text: Add a note for which commands fcntl acts a cancellation point. * nptl/Makefile (CFLAGS-fcntl64.c): New rule. * sysdeps/mach/hurd/fcntl.c: Alias fcntl to fcntl64 symbols. * sysdeps/mach/hurd/i386/libc.abilist [GLIBC_2.28] (fcntl, fcntl64): New symbols. * sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Fix F_GETLK64, F_OFD_GETLK, F_SETLK64, F_SETLKW64, F_OFD_SETLK, and F_OFD_SETLKW for non-LFS case. * sysdeps/unix/sysv/linux/fcntl64.c: New file. * sysdeps/unix/sysv/linux/fcntl_nocancel.c (__fcntl_nocancel): Rename to __fcntl64_nocancel. (__fcntl_nocancel_adjusted): Rename to __fcntl64_nocancel_adjusted. * sysdeps/unix/sysv/linux/not-cancel.h (__fcntl_nocancel): Rename to __fcntl64_nocancel. * sysdeps/unix/sysv/linux/tst-ofdlocks.c: New file. * sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Likewise. * sysdeps/unix/sysv/linux/Makefile (tests): Add tst-ofdlocks. (tests-internal): Add tst-ofdlocks-compat. * sysdeps/unix/sysv/linux/aarch64/libc.abilist [GLIBC_2.28] (fcntl64): New symbol. * sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise. * sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/arm/libc.abilist [GLIBC_2.28] (fcntl, fcntl64): Likewise. * sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/i386/libc.abilis: Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
2018-06-12Fix fallback path in __pthread_mutex_timedlock ().Carlos O'Donell
Fix the typo in the fallback path in __pthread_mutex_timedlock () whic hcalls lll_futex_timed_wait (). This is only useful for cases where the patch is being backported to older distributions where only lll_futex_timed_wait () is available.
2018-06-12Avoid cancellable I/O primitives in ld.so.Zack Weinberg
Neither the <dlfcn.h> entry points, nor lazy symbol resolution, nor initial shared library load-up, are cancellation points, so ld.so should exclusively use I/O primitives that are not cancellable. We currently achieve this by having the cancellation hooks compile as no-ops when IS_IN(rtld); this patch changes to using exclusively _nocancel primitives in the source code instead, which makes the intent clearer and significantly reduces the amount of code compiled under IS_IN(rtld) as well as IS_IN(libc) -- in particular, elf/Makefile no longer thinks we require a copy of unwind.c in rtld-libc.a. (The older mechanism is preserved as a backstop.) The bulk of the change is splitting up the files that define the _nocancel I/O functions, so they don't also define the variants that *are* cancellation points; after which, the existing logic for picking out the bits of libc that need to be recompiled as part of ld.so Just Works. I did this for all of the _nocancel functions, not just the ones used by ld.so, for consistency. fcntl was a little tricky because it's only a cancellation point for certain opcodes (F_SETLKW(64), which can block), and the existing __fcntl_nocancel wasn't applying the FCNTL_ADJUST_CMD hook, which strikes me as asking for trouble, especially as the only nontrivial definition of FCNTL_ADJUST_CMD (for powerpc64) changes F_*LK* opcodes. To fix this, fcntl_common moves to fcntl_nocancel.c along with __fcntl_nocancel, and changes its name to the extern (but hidden) symbol __fcntl_nocancel_adjusted, so that regular fcntl can continue calling it. __fcntl_nocancel now applies FCNTL_ADJUST_CMD; so that both both fcntl.c and fcntl_nocancel.c can see it, the only nontrivial definition moves from sysdeps/u/s/l/powerpc/powerpc64/fcntl.c to .../powerpc64/sysdep.h and becomes entirely a macro, instead of a macro that calls an inline function. The nptl version of libpthread also changes a little, because its "compat-routines" formerly included files that defined all the _nocancel functions it uses; instead of continuing to duplicate them, I exported the relevant ones from libc.so as GLIBC_PRIVATE. Since the Linux fcntl.c calls a function defined by fcntl_nocancel.c, it can no longer be used from libpthread.so; instead, introduce a custom forwarder, pt-fcntl.c, and export __libc_fcntl from libc.so as GLIBC_PRIVATE. The nios2-linux ABI doesn't include a copy of vfork() in libpthread, and it was handling that by manipulating libpthread-routines in .../linux/nios2/Makefile; it is cleaner to do what other such ports do, and have a pt-vfork.S that defines no symbols. Right now, it appears that Hurd does not implement _nocancel I/O, so sysdeps/generic/not-cancel.h will forward everything back to the regular functions. This changed the names of some of the functions that sysdeps/mach/hurd/dl-sysdep.c needs to interpose. * elf/dl-load.c, elf/dl-misc.c, elf/dl-profile.c, elf/rtld.c * sysdeps/unix/sysv/linux/dl-sysdep.c Include not-cancel.h. Use __close_nocancel instead of __close, __open64_nocancel instead of __open, __read_nocancel instead of __libc_read, and __write_nocancel instead of __libc_write. * csu/check_fds.c (check_one_fd) * sysdeps/posix/fdopendir.c (__fdopendir) * sysdeps/posix/opendir.c (__alloc_dir): Use __fcntl_nocancel instead of __fcntl and/or __libc_fcntl. * sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np) * sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np) * sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system): Use __open64_nocancel instead of __open_nocancel. * sysdeps/unix/sysv/linux/not-cancel.h: Move all of the hidden_proto declarations to the end and issue them if either IS_IN(libc) or IS_IN(rtld). * sysdeps/unix/sysv/linux/Makefile [subdir=io] (sysdep_routines): Add close_nocancel, fcntl_nocancel, nanosleep_nocancel, open_nocancel, open64_nocancel, openat_nocancel, pause_nocancel, read_nocancel, waitpid_nocancel, write_nocancel. * io/Versions [GLIBC_PRIVATE]: Add __libc_fcntl, __fcntl_nocancel, __open64_nocancel, __write_nocancel. * posix/Versions: Add __nanosleep_nocancel, __pause_nocancel. * nptl/pt-fcntl.c: New file. * nptl/Makefile (pthread-compat-wrappers): Remove fcntl. (libpthread-routines): Add pt-fcntl. * include/fcntl.h (__fcntl_nocancel_adjusted): New function. (__libc_fcntl): Remove attribute_hidden. * sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Call __fcntl_nocancel_adjusted, not fcntl_common. (__fcntl_nocancel): Move to new file fcntl_nocancel.c. (fcntl_common): Rename to __fcntl_nocancel_adjusted; also move to fcntl_nocancel.c. * sysdeps/unix/sysv/linux/fcntl_nocancel.c: New file. * sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Remove file. * sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h: Define FCNTL_ADJUST_CMD here, as a self-contained macro. * sysdeps/unix/sysv/linux/close.c: Move __close_nocancel to... * sysdeps/unix/sysv/linux/close_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/nanosleep.c: Move __nanosleep_nocancel to... * sysdeps/unix/sysv/linux/nanosleep_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/open.c: Move __open_nocancel to... * sysdeps/unix/sysv/linux/open_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/open64.c: Move __open64_nocancel to... * sysdeps/unix/sysv/linux/open64_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/openat.c: Move __openat_nocancel to... * sysdeps/unix/sysv/linux/openat_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/openat64.c: Move __openat64_nocancel to... * sysdeps/unix/sysv/linux/openat64_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/pause.c: Move __pause_nocancel to... * sysdeps/unix/sysv/linux/pause_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/read.c: Move __read_nocancel to... * sysdeps/unix/sysv/linux/read_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/waitpid.c: Move __waitpid_nocancel to... * sysdeps/unix/sysv/linux/waitpid_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/write.c: Move __write_nocancel to... * sysdeps/unix/sysv/linux/write_nocancel.c: ...this new file. * sysdeps/unix/sysv/linux/nios2/Makefile: Don't override libpthread-routines. * sysdeps/unix/sysv/linux/nios2/pt-vfork.S: New file which defines nothing. * sysdeps/mach/hurd/dl-sysdep.c: Define __read instead of __libc_read, and __write instead of __libc_write. Define __open64 in addition to __open.
2018-05-17nptl: Remove __ASSUME_PRIVATE_FUTEXH.J. Lu
Since __ASSUME_PRIVATE_FUTEX is always defined, this patch removes the !__ASSUME_PRIVATE_FUTEX paths. Tested with build-many-glibcs.py. * nptl/allocatestack.c (allocate_stack): Remove the !__ASSUME_PRIVATE_FUTEX paths. * nptl/descr.h (header): Remove the !__ASSUME_PRIVATE_FUTEX path. * nptl/nptl-init.c (__pthread_initialize_minimal_internal): Likewise. * sysdeps/i386/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Removed. * sysdeps/powerpc/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Likewise. * sysdeps/sh/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Likewise. * sysdeps/i386/nptl/tls.h: (tcbhead_t): Remve the !__ASSUME_PRIVATE_FUTEX path. * sysdeps/s390/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/sparc/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/unix/sysv/linux/i386/lowlevellock.S: Remove the !__ASSUME_PRIVATE_FUTEX macros. * sysdeps/unix/sysv/linux/lowlevellock-futex.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/cancellation.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_PRIVATE_FUTEX): Removed.
2018-05-02x86: Use pad in pthread_unwind_buf to preserve shadow stack registerH.J. Lu
The pad array in struct pthread_unwind_buf is used by setjmp to save shadow stack register. We assert that size of struct pthread_unwind_buf is no less than offset of shadow stack pointer + shadow stack pointer size. Since functions, like LIBC_START_MAIN, START_THREAD_DEFN as well as these with thread cancellation, call setjmp, but never return after __libc_unwind_longjmp, __libc_unwind_longjmp, which is defined as __libc_longjmp on x86, doesn't need to restore shadow stack register. __libc_longjmp, which is a private interface for thread cancellation implementation in libpthread, is changed to call __longjmp_cancel, instead of __longjmp. __longjmp_cancel is a new internal function in libc, which is similar to __longjmp, but doesn't restore shadow stack register. The compatibility longjmp and siglongjmp in libpthread.so are changed to call __libc_siglongjmp, instead of __libc_longjmp, so that they will restore shadow stack register. Tested with build-many-glibcs.py. Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com> * nptl/pthread_create.c (START_THREAD_DEFN): Clear previous handlers after setjmp. * setjmp/longjmp.c (__libc_longjmp): Don't define alias if defined. * sysdeps/unix/sysv/linux/x86/setjmpP.h: Include <libc-pointer-arith.h>. (_JUMP_BUF_SIGSET_BITS_PER_WORD): New. (_JUMP_BUF_SIGSET_NSIG): Changed to 96. (_JUMP_BUF_SIGSET_NWORDS): Changed to use ALIGN_UP and _JUMP_BUF_SIGSET_BITS_PER_WORD. * sysdeps/x86/Makefile (sysdep_routines): Add __longjmp_cancel. * sysdeps/x86/__longjmp_cancel.S: New file. * sysdeps/x86/longjmp.c: Likewise. * sysdeps/x86/nptl/pt-longjmp.c: Likewise.
2018-04-03Filter out NPTL internal signals (BZ #22391)Adhemerval Zanella
This patch filters out the internal NPTL signals (SIGCANCEL/SIGTIMER and SIGSETXID) from signal functions. GLIBC on Linux requires both signals to proper implement pthread cancellation, posix timers, and set*id posix thread synchronization. And not filtering out the internal signal is troublesome: - A conformant program on a architecture that does not filter out the signals might inadvertently disable pthread asynchronous cancellation, set*id synchronization or posix timers. - It might also to security issues if SIGSETXID is masked and set*id functions are called (some threads might have effective user or group id different from the rest). The changes are basically: - Change __is_internal_signal to bool and used on all signal function that has a signal number as input. Also for signal function which accepts signals sets (sigset_t) it assumes that canonical function were used to add/remove signals which lead to some input simplification. - Fix tst-sigset.c to avoid check for SIGCANCEL/SIGTIMER and SIGSETXID. It is rewritten to check each signal indidually and to check realtime signals using canonical macros. - Add generic __clear_internal_signals and __is_internal_signal version since both symbols are used on generic implementations. - Remove superflous sysdeps/nptl/sigfillset.c. - Remove superflous SIGTIMER handling on Linux __is_internal_signal since it is the same of SIGCANCEL. - Remove dangling define and obvious comment on nptl/sigaction.c. Checked on x86_64-linux-gnu. [BZ #22391] * nptl/sigaction.c (__sigaction): Use __is_internal_signal to check for internal nptl signals. * nptl/sigaction.c (__sigaction): Likewise. * signal/sigaddset.c (sigaddset): Likewise. * signal/sigdelset.c (sigdelset): Likewise. * sysdeps/posix/signal.c (__bsd_signal): Likewise. * sysdeps/posix/sigset.c (sigset): Call and check sigaddset return value. * signal/sigfillset.c (sigfillset): User __clear_internal_signals to filter out internal nptl signals. * signal/tst-sigset.c (do_test): Check ech signal indidually and also check realtime signals using standard macros. * sysdeps/generic/internal-signals.h (__clear_internal_signals, __is_internal_signal, __libc_signal_block_all, __libc_signal_block_app, __libc_signal_restore_set): New functions. * sysdeps/nptl/sigfillset.c: Remove file. * sysdeps/unix/sysv/linux/internal-signals.h (__is_internal_signal): Change return to bool. (__clear_internal_signals): Remove SIGTIMER clean since it is equal to SIGCANEL on Linux. * sysdeps/unix/sysv/linux/sigtimedwait.c (__sigtimedwait): Assume signal set was constructed using standard functions. Reported-by: Yury Norov <ynorov@caviumnetworks.com>
2018-03-05nptl: Fix tst-cancel4 sendto testsAdhemerval Zanella
Now that send might be implemented calling sendto syscall on Linux, I am seeing some issue in some kernel configurations where tst-cancel4 sendto do not block as expected. The socket used to force the syscall blocking is used with default system configuration for buffer sending size, which might not be suffice to force blocking. This patch fixes it by explicit setting buffer socket lower than the buffer size used. It also enables sendto cancellation tests to work in both ways (since internally send is implemented routing to sendto on Linux kernel). The patch also removes unrequired make rules on some archictures for send/recv. The generic nptl Makefile already set the compiler flags required on some architectures for correct unwinding and libc object are not strictly required to support unwind (since pthread_cancel requires linking against libpthread). Checked on aarch64-linux-gnu and x86_64-linux-gnu. I also did a sniff test with tst-cancel{4,5} on a simulated mips64-linux-gnu. * nptl/tst-cancel4-common.h (set_socket_buffer): New function. * nptl/tst-cancel4-common.c (do_test): Call set_socket_buffer for socketpair endpoint. * nptl/tst-cancel4.c (tf_send): Call set_socket_buffer and use WRITE_BUFFER_SIZE as buffer size for sending socket. (tf_sendto): Use SOCK_STREAM instead of SOCK_DGRAM and fix an issue on system where send is implemented with sendto syscall. * sysdeps/unix/sysv/linux/mips/mips64/Makefile [$(subdir) = socket] (CFLAGS-recv.c, CFLAGS-send.c): Remove rules. [$(subdir) = nptl] (CFLAGS-recv.c, CFLAGS-send.c): Likewise. * sysdeps/unix/sysv/linux/riscv/rv64/Makefile: Remove file.
2018-03-01nptl: Turn libpthread.so into a symbolic link to the real DSOFlorian Weimer
The linker script is no longer needed.
2018-03-01nptl: Drop libpthread_nonshared.a from libpthread.soFlorian Weimer
Fixes commit bd60ce86520b781ca24b99b2555e2ad389bbfeaa (nptl: Move pthread_atfork to libc_nonshared.a).
2018-03-01nptl: Move pthread_atfork to libc_nonshared.aFlorian Weimer
libpthread_nonshared.a is unused after this, so remove it from the build. There is no ABI impact because pthread_atfork was implemented using __register_atfork in libc even before this change. pthread_atfork has to be a weak alias because pthread_* names are not reserved in libc. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-02-22Refactor atfork handlersAdhemerval Zanella
Current implementation (sysdeps/nptl/fork.c) replicates the atfork handlers list backward to invoke the child handlers after fork/clone syscall. The internal atfork handlers is implemented as a single-linked list so a lock-free algorithm can be used, trading fork mulithread call performance for some code complexity and dynamic stack allocation (since the backwards list should not fail). This patch refactor it to use a dynarary instead of a linked list. It simplifies the external variables need to be exported and also the internal atfork handler member definition. The downside is a serialization of fork call in multithread, since to operate on the dynarray the internal lock should be used. However as noted by Florian, it already acquires external locks for malloc and libio so it is already hitting some lock contention. Besides, posix_spawn should be faster and more scalable to run external programs in multithread environments. Checked on x86_64-linux-gnu. * nptl/Makefile (routines): Remove unregister-atfork. * nptl/register-atfork.c (fork_handler_pool): Remove variable. (fork_handler_alloc): Remove function. (fork_handlers, fork_handler_init): New variables. (__fork_lock): Rename to atfork_lock. (__register_atfork, __unregister_atfork, libc_freeres_fn): Rewrite to use a dynamic array to add/remove atfork handlers. * sysdeps/nptl/fork.c (__libc_fork): Likewise. * sysdeps/nptl/fork.h (__fork_lock, __fork_handlers, __linkin_atfork): Remove declaration. (fork_handler): Remove next, refcntr, and need_signal member. (__run_fork_handler_type): New enum. (__run_fork_handlers): New prototype. * sysdeps/nptl/libc-lockP.h (__libc_atfork): Remove declaration.
2018-02-22Rename nptl-signals.h to internal-signals.hAdhemerval Zanella
This patch renames the nptl-signals.h header to internal-signals.h. On Linux the definitions and functions are not only NPTL related, but used for other POSIX definitions as well (for instance SIGTIMER for posix times, SIGSETXID for id functions, and signal block/restore helpers) and since generic functions will be places and used in generic implementation it makes more sense to decouple it from NPTL. Checked on x86_64-linux-gnu. * sysdeps/nptl/nptl-signals.h: Move to ... * sysdeps/generic/internal-signals.h: ... here. Adjust internal comments. * sysdeps/unix/sysv/linux/internal-signals.h: Add include guards. (__nptl_is_internal_signal): Rename to __is_internal_signal. (__nptl_clear_internal_signals): Rename to __clear_internal_signals. * sysdeps/unix/sysv/linux/raise.c: Adjust nptl-signal.h to include-signals.h rename. * nptl/pthreadP.h: Likewise. * sysdeps/unix/sysv/linux/spawni.c (__spawni_child): Call __is_internal_signal instead of __nptl_is_internal_signal.
2018-02-16Add runtime check if mutex will be elided in tst-mutex8 testcases.Stefan Liebler
An elided mutex don't fail destroy. Elision was disabled for the test nptl/tst-mutex8 in nptl/Makefile. Thus we can run tests which destroy a locked mutex. As elision is only disabled for tst-mutex8, the variants tst-mutex8-static, tst-mutexpi8 and tst-mutexpi8-static are still failing if lock elision is enabled. This patch adds a runtime check, if the checked type of mutex will be elided. This check is using TUNABLE_GET_FULL to determine if elision is enabled via the tunables framework. The pthread_mutex_destroy tests are only run if we dont't assume an elided mutex. This way, we can run the whole glibc testsuite with or without enabled lock elision. ChangeLog: * nptl/Makefile (tst-mutex8-ENV): Delete. * nptl/tst-mutex8.c (check_type): Add runtime check if mutex will be elided.
2018-01-25Revert Intel CET changes to __jmp_buf_tag (Bug 22743)Carlos O'Donell
In commit cba595c350e52194e10c0006732e1991e3d0803b and commit f81ddabffd76ac9dd600b02adbf3e1dac4bb10ec, ABI compatibility with applications was broken by increasing the size of the on-stack allocated __pthread_unwind_buf_t beyond the oringal size. Applications only have the origianl space available for __pthread_unwind_register, and __pthread_unwind_next to use, any increase in the size of __pthread_unwind_buf_t causes these functions to write beyond the original structure into other on-stack variables leading to segmentation faults in common applications like vlc. The only workaround is to version those functions which operate on the old sized objects, but this must happen in glibc 2.28. Thank you to Andrew Senkevich, H.J. Lu, and Aurelien Jarno, for submitting reports and tracking the issue down. The commit reverts the above mentioned commits and testing on x86_64 shows that the ABI compatibility is restored. A tst-cleanup1 regression test linked with an older glibc now passes when run with the newly built glibc. Previously a tst-cleanup1 linked with an older glibc would segfault when run with an affected glibc build. Tested on x86_64 with no regressions. Signed-off-by: Carlos O'Donell <carlos@redhat.com>