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* Define PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN)H.J. Lu2021-07-091-2/+2
| | | | | | | | | | | | | The constant PTHREAD_STACK_MIN may be too small for some processors. Rename _SC_SIGSTKSZ_SOURCE to _DYNAMIC_STACK_SIZE_SOURCE. When _DYNAMIC_STACK_SIZE_SOURCE or _GNU_SOURCE are defined, define PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN) which is changed to MIN (PTHREAD_STACK_MIN, sysconf(_SC_MINSIGSTKSZ)). Consolidate <bits/local_lim.h> with <bits/pthread_stack_min.h> to provide a constant target specific PTHREAD_STACK_MIN value. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* io: Add closefrom [BZ #10353]Adhemerval Zanella2021-07-081-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function closes all open file descriptors greater than or equal to input argument. Negative values are clamped to 0, i.e, it will close all file descriptors. As indicated by the bug report, this is a common symbol provided by different systems (Solaris, OpenBSD, NetBSD, FreeBSD) and, although its has inherent issues with not taking in consideration internal libc file descriptors (such as syslog), this is also a common feature used in multiple projects [1][2][3][4][5]. The Linux fallback implementation iterates over /proc and close all file descriptors sequentially. Although it was raised the questioning whether getdents on /proc/self/fd might return disjointed entries when file descriptor are closed; it does not seems the case on my testing on multiple kernel (v4.18, v5.4, v5.9) and the same strategy is used on different projects [1][2][3][5]. Also, the interface is set a fail-safe meaning that a failure in the fallback results in a process abort. Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15. [1] https://github.com/systemd/systemd/blob/5238e9575906297608ff802a27e2ff9effa3b338/src/basic/fd-util.c#L217 [2] https://github.com/lxc/lxc/blob/ddf4b77e11a4d08f09b7b9cd13e593f8c047edc5/src/lxc/start.c#L236 [3] https://github.com/python/cpython/blob/9e4f2f3a6b8ee995c365e86d976937c141d867f8/Modules/_posixsubprocess.c#L220 [4] https://github.com/rust-lang/rust/blob/5f47c0613ed4eb46fca3633c1297364c09e5e451/src/libstd/sys/unix/process2.rs#L303-L308 [5] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
* linux: Add close_rangeAdhemerval Zanella2021-07-081-0/+51
| | | | | | | | | | It was added on Linux 5.9 (278a5fbaed89) with CLOSE_RANGE_CLOEXEC added on 5.11 (582f1fb6b721f). Although FreeBSD has added the same syscall, this only adds the symbol on Linux ports. This syscall is required to provided a fail-safe way to implement the closefrom symbol (BZ #10353). Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.
* glibc.malloc.check: Fix nit in documentationSiddhesh Poyarekar2021-07-072-6/+6
| | | | | | | The tunable will not work with *any* non-zero tunable value since its list of allowed values is 0-3. Fix the documentation to reflect that. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* manual: fix description for preadv()Armin Brauns2021-07-061-1/+1
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* x86: Check RTM_ALWAYS_ABORT for RTM [BZ #28033]H.J. Lu2021-07-011-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | From https://www.intel.com/content/www/us/en/support/articles/000059422/processors.html * Intel TSX will be disabled by default. * The processor will force abort all Restricted Transactional Memory (RTM) transactions by default. * A new CPUID bit CPUID.07H.0H.EDX[11](RTM_ALWAYS_ABORT) will be enumerated, which is set to indicate to updated software that the loaded microcode is forcing RTM abort. * On processors that enumerate support for RTM, the CPUID enumeration bits for Intel TSX (CPUID.07H.0H.EBX[11] and CPUID.07H.0H.EBX[4]) continue to be set by default after microcode update. * Workloads that were benefited from Intel TSX might experience a change in performance. * System software may use a new bit in Model-Specific Register (MSR) 0x10F TSX_FORCE_ABORT[TSX_CPUID_CLEAR] functionality to clear the Hardware Lock Elision (HLE) and RTM bits to indicate to software that Intel TSX is disabled. 1. Add RTM_ALWAYS_ABORT to CPUID features. 2. Set RTM usable only if RTM_ALWAYS_ABORT isn't set. This skips the string/tst-memchr-rtm etc. testcases on the affected processors, which always fail after a microcde update. 3. Check RTM feature, instead of usability, against /proc/cpuinfo. This fixes BZ #28033.
* posix: Add _Fork [BZ #4737]Adhemerval Zanella2021-06-281-15/+26
| | | | | | | | | | | | | | | | | | | | | | | | | Austin Group issue 62 [1] dropped the async-signal-safe requirement for fork and provided a async-signal-safe _Fork replacement that does not run the atfork handlers. It will be included in the next POSIX standard. It allow to close a long standing issue to make fork AS-safe (BZ#4737). As indicated on the bug, besides the internal lock for the atfork handlers itself; there is no guarantee that the handlers itself will not introduce more AS-safe issues. The idea is synchronize fork with the required internal locks to allow children in multithread processes to use mostly of standard function (even though POSIX states only AS-safe function should be used). On signal handles, _Fork should be used intead and only AS-safe functions should be used. For testing, the new tst-_Fork only check basic usage. I also added a new tst-mallocfork3 which uses the same strategy to check for deadlock of tst-mallocfork2 but using threads instead of subprocesses (and it does deadlock if it replaces _Fork with fork). [1] https://austingroupbugs.net/view.php?id=62
* nptl: Add glibc.pthread.stack_cache_size tunableFlorian Weimer2021-06-281-0/+9
| | | | | | | The valgrind/helgrind test suite needs a way to make stack dealloction more prompt, and this feature seems to be generally useful. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* x86: Fix tst-cpu-features-cpuinfo on Ryzen 9 (BZ #27873)Adhemerval Zanella2021-06-241-0/+12
| | | | | | | | | | | | | | | | | | | AMD define different flags for IRPB, IBRS, and STIPBP [1], so new x86_64_cpu are added and IBRS_IBPB is only tested for Intel. The SSDB is also defined and implemented different on AMD [2], and also a new AMD_SSDB flag is added. It should map to the cpuinfo 'ssdb' on recent AMD cpus. It fixes tst-cpu-features-cpuinfo and tst-cpu-features-cpuinfo-static on recent AMD cpus. Checked on x86_64-linux-gnu on AMD Ryzen 9 5900X. [1] https://developer.amd.com/wp-content/resources/Architecture_Guidelines_Update_Indirect_Branch_Control.pdf [2] https://bugzilla.kernel.org/show_bug.cgi?id=199889 Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* doc: _TIME_BITS defaults may changePaul Eggert2021-06-231-29/+28
| | | | | | | * NEWS: Don't imply the default will always be 32-bit. * manual/creature.texi (Feature Test Macros): Say that _TIME_BITS and _FILE_OFFSET_BITS defaults may change in future releases.
* y2038: Add support for 64-bit time on legacy ABIsAdhemerval Zanella2021-06-151-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A new build flag, _TIME_BITS, enables the usage of the newer 64-bit time symbols for legacy ABI (where 32-bit time_t is default). The 64 bit time support is only enabled if LFS (_FILE_OFFSET_BITS=64) is also used. Different than LFS support, the y2038 symbols are added only for the required ABIs (armhf, csky, hppa, i386, m68k, microblaze, mips32, mips64-n32, nios2, powerpc32, sparc32, s390-32, and sh). The ABIs with 64-bit time support are unchanged, both for symbol and types redirection. On Linux the full 64-bit time support requires a minimum of kernel version v5.1. Otherwise, the 32-bit fallbacks are used and might results in error with overflow return code (EOVERFLOW). The i686-gnu does not yet support 64-bit time. This patch exports following rediretions to support 64-bit time: * libc: adjtime adjtimex clock_adjtime clock_getres clock_gettime clock_nanosleep clock_settime cnd_timedwait ctime ctime_r difftime fstat fstatat futimens futimes futimesat getitimer getrusage gettimeofday gmtime gmtime_r localtime localtime_r lstat_time lutimes mktime msgctl mtx_timedlock nanosleep nanosleep ntp_gettime ntp_gettimex ppoll pselec pselect pthread_clockjoin_np pthread_cond_clockwait pthread_cond_timedwait pthread_mutex_clocklock pthread_mutex_timedlock pthread_rwlock_clockrdlock pthread_rwlock_clockwrlock pthread_rwlock_timedrdlock pthread_rwlock_timedwrlock pthread_timedjoin_np recvmmsg sched_rr_get_interval select sem_clockwait semctl semtimedop sem_timedwait setitimer settimeofday shmctl sigtimedwait stat thrd_sleep time timegm timerfd_gettime timerfd_settime timespec_get utime utimensat utimes utimes wait3 wait4 * librt: aio_suspend mq_timedreceive mq_timedsend timer_gettime timer_settime * libanl: gai_suspend Reviewed-by: Lukasz Majewski <lukma@denx.de> Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
* Add build option to disable usage of scv on powerpcMatheus Castanho2021-06-101-0/+4
| | | | | | | | | | | | | | | | | Commit 68ab82f56690ada86ac1e0c46bad06ba189a10ef added support for the scv syscall ABI on powerpc. Since then systems that have kernel and processor support started using scv. However adding the proper support for a new syscall ABI requires changes to several other projects (e.g. qemu, valgrind, strace, kernel), which are gradually receiving support. Meanwhile, having a way to disable scv on glibc at build time can be useful for distros that may encounter conflicts with projects that still do not support the scv ABI, buying time until proper support is added. This commit adds a --disable-scv option that disables scv support and uses sc for all syscalls, like before commit 68ab82f56690ada86ac1e0c46bad06ba189a10ef. Reviewed-by: Raphael M Zinsly <rzinsly@linux.ibm.com>
* nptl: Move cancel state out of cancelhandlingAdhemerval Zanella2021-06-092-3/+1
| | | | | | | | | | | | | | | Now that thread cancellation state is not accessed concurrently anymore, it is possible to move it out the 'cancelhandling'. The code is also simplified: CANCELLATION_P is replaced with a internal pthread_testcancel call and the CANCELSTATE_BIT{MASK} is removed. With this behavior pthread_setcancelstate does not require to act on cancellation if cancel type is asynchronous (is already handled either by pthread_setcanceltype or by the signal handler). Checked on x86_64-linux-gnu and aarch64-linux-gnu.
* fix typoXeonacid2021-06-021-1/+1
| | | | | "accomodate" should be "accommodate" Reviewed-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* Update floating-point feature test macro handling for C2XJoseph Myers2021-06-011-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ISO C2X has made some changes to the handling of feature test macros related to features from the floating-point TSes, and to exactly what such features are present in what headers, that require corresponding changes in glibc. * For the few features that were controlled by __STDC_WANT_IEC_60559_BFP_EXT__ (and the corresponding DFP macro) in C2X, there is now instead a new feature test macro __STDC_WANT_IEC_60559_EXT__ covering both binary and decimal FP. This controls CR_DECIMAL_DIG in <float.h> (provided by GCC; I implemented support for the new feature test macro for GCC 11) and the totalorder and payload functions in <math.h>. C2X no longer says anything about __STDC_WANT_IEC_60559_BFP_EXT__ (so it's appropriate for that macro to continue to enable exactly the features from TS 18661-1). * The SNAN macros for each floating-point type have moved to <float.h> (and been renamed in the process). Thus, the copies in <math.h> should only be defined for __STDC_WANT_IEC_60559_BFP_EXT__, not for C2X. * The fmaxmag and fminmag functions have been removed (replaced by new functions for the new min/max operations in IEEE 754-2019). Thus those should also only be declared for __STDC_WANT_IEC_60559_BFP_EXT__. * The _FloatN / _FloatNx handling for the last two points in glibc is trickier, since __STDC_WANT_IEC_60559_TYPES_EXT__ is still in C2X (the integration of TS 18661-3 as an Annex, that is, which hasn't yet been merged into the C standard git repository but has been accepted by WG14), so C2X with that macro should not declare some things that are declared for older standards with that macro. The approach taken here is to provide the declarations (when __STDC_WANT_IEC_60559_TYPES_EXT__ is enabled) only when (defined __USE_GNU || !__GLIBC_USE (ISOC2X)), so if C2X features are enabled then those declarations (that are only in TS 18661-3 and not in C2X) will only be provided if _GNU_SOURCE is defined as well. Thus _GNU_SOURCE remains a superset of the TS features as well as of C2X. Some other somewhat related changes in C2X are not addressed here. There's an open proposal not to include the fmin and fmax functions for the _FloatN / _FloatNx types, given the new min/max operations, which could be handled like the previous point if adopted. And the fromfp functions have been changed to return a result in floating type rather than intmax_t / uintmax_t; my inclination there is to treat that like that change of totalorder type (new symbol versions etc. for the ABI change; old versions become compat symbols and are no longer supported as an API). Tested for x86_64 and x86.
* aarch64: Added optimized memcpy and memmove for A64FXNaohiro Tamura2021-05-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch optimizes the performance of memcpy/memmove for A64FX [1] which implements ARMv8-A SVE and has L1 64KB cache per core and L2 8MB cache per NUMA node. The performance optimization makes use of Scalable Vector Register with several techniques such as loop unrolling, memory access alignment, cache zero fill, and software pipelining. SVE assembler code for memcpy/memmove is implemented as Vector Length Agnostic code so theoretically it can be run on any SOC which supports ARMv8-A SVE standard. We confirmed that all testcases have been passed by running 'make check' and 'make xcheck' not only on A64FX but also on ThunderX2. And also we confirmed that the SVE 512 bit vector register performance is roughly 4 times better than Advanced SIMD 128 bit register and 8 times better than scalar 64 bit register by running 'make bench'. [1] https://github.com/fujitsu/A64FX Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com> Reviewed-by: Szabolcs Nagy <Szabolcs.Nagy@arm.com>
* aarch64: Added Vector Length Set test helper scriptNaohiro Tamura2021-05-261-0/+3
| | | | | | | | | | | | | | | | | | | This patch is a test helper script to change Vector Length for child process. This script can be used as test-wrapper for 'make check'. Usage examples: ~/build$ make check subdirs=string \ test-wrapper='~/glibc/sysdeps/unix/sysv/linux/aarch64/vltest.py 16' ~/build$ ~/glibc/sysdeps/unix/sysv/linux/aarch64/vltest.py 16 \ make test t=string/test-memcpy ~/build$ ~/glibc/sysdeps/unix/sysv/linux/aarch64/vltest.py 32 \ ./debugglibc.sh string/test-memmove ~/build$ ~/glibc/sysdeps/unix/sysv/linux/aarch64/vltest.py 64 \ ./testrun.sh string/test-memset
* nptl: Consolidate async cancel enable/disable implementation in libcFlorian Weimer2021-05-051-2/+2
| | | | | | | | | | | | | | Previously, the source file nptl/cancellation.c was compiled multiple times, for libc, libpthread, librt. This commit switches to a single implementation, with new __pthread_enable_asynccancel@@GLIBC_PRIVATE, __pthread_disable_asynccancel@@GLIBC_PRIVATE exports. The almost-unused CANCEL_ASYNC and CANCEL_RESET macros are replaced by LIBC_CANCEL_ASYNC and LIBC_CANCEL_ASYNC macros. They call the __pthread_* functions unconditionally now. The macros are still needed because shared code uses them; Hurd has different definitions. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Improve documentation for malloc etc. (BZ#27719)Paul Eggert2021-04-138-90/+136
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cover key corner cases (e.g., whether errno is set) that are well settled in glibc, fix some examples to avoid integer overflow, and update some other dated examples (code needed for K&R C, e.g.). * manual/charset.texi (Non-reentrant String Conversion): * manual/filesys.texi (Symbolic Links): * manual/memory.texi (Allocating Cleared Space): * manual/socket.texi (Host Names): * manual/string.texi (Concatenating Strings): * manual/users.texi (Setting Groups): Use reallocarray instead of realloc, to avoid integer overflow issues. * manual/filesys.texi (Scanning Directory Content): * manual/memory.texi (The GNU Allocator, Hooks for Malloc): * manual/tunables.texi: Use code font for 'malloc' instead of roman font. (Symbolic Links): Don't assume readlink return value fits in 'int'. * manual/memory.texi (Memory Allocation and C, Basic Allocation) (Malloc Examples, Alloca Example): * manual/stdio.texi (Formatted Output Functions): * manual/string.texi (Concatenating Strings, Collation Functions): Omit pointer casts that are needed only in ancient K&R C. * manual/memory.texi (Basic Allocation): Say that malloc sets errno on failure. Say "convert" rather than "cast", since casts are no longer needed. * manual/memory.texi (Basic Allocation): * manual/string.texi (Concatenating Strings): In examples, use C99 declarations after statements for brevity. * manual/memory.texi (Malloc Examples): Add portability notes for malloc (0), errno setting, and PTRDIFF_MAX. (Changing Block Size): Say that realloc (p, 0) acts like (p ? (free (p), NULL) : malloc (0)). Add xreallocarray example, since other examples can use it. Add portability notes for realloc (0, 0), realloc (p, 0), PTRDIFF_MAX, and improve notes for reallocating to the same size. (Allocating Cleared Space): Reword now-confusing discussion about replacement, and xref "Replacing malloc". * manual/stdio.texi (Formatted Output Functions): Don't assume message size fits in 'int'. * manual/string.texi (Concatenating Strings): Fix undefined behavior involving arithmetic on a freed pointer.
* manual: clarify that scanf %n supports type modifiersAlyssa Ross2021-03-301-5/+6
| | | | | | | | | | My initial reading of the %n documentation was that it didn't support type conversions, because it only mentioned int*. Corresponding man-pages patch: https://lore.kernel.org/linux-man/20210328215509.31666-1-hi@alyssa.is/ Reviewed-by: Arjun Shankar <arjun@redhat.com>
* math: Remove mpa files [BZ #15267]Wilco Dijkstra2021-03-111-85/+0
| | | | | | | Finally remove all mpa related files, headers, declarations, probes, unused tables and update makefiles. Reviewed-By: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* tst: Extend cross-test-ssh.sh to specify if target date can be alteredLukasz Majewski2021-03-081-0/+20
| | | | | | | | | | | | | This code adds new flag - '--allow-time-setting' to cross-test-ssh.sh script to indicate if it is allowed to alter the date on the system on which tests are executed. This change is supposed to be used with test systems, which use virtual machines for testing. The GLIBC_TEST_ALLOW_TIME_SETTING env variable is exported to the remote environment on which the eligible test is run and brings no functional change when it is not. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* tunables: Simplify TUNABLE_SET interfaceSiddhesh Poyarekar2021-02-101-9/+7
| | | | | | | | | | | | | | | The TUNABLE_SET interface took a primitive C type argument, which resulted in inconsistent type conversions internally due to incorrect dereferencing of types, especialy on 32-bit architectures. This change simplifies the TUNABLE setting logic along with the interfaces. Now all numeric tunable values are stored as signed numbers in tunable_num_t, which is intmax_t. All calls to set tunables cast the input value to its primitive type and then to tunable_num_t for storage. This relies on gcc-specific (although I suspect other compilers woul also do the same) unsigned to signed integer conversion semantics, i.e. the bit pattern is conserved. The reverse conversion is guaranteed by the standard.
* x86: Add PTWRITE feature detection [BZ #27346]H.J. Lu2021-02-071-0/+3
| | | | | | | 1. Add CPUID_INDEX_14_ECX_0 for CPUID leaf 0x14 to detect PTWRITE feature in EBX of CPUID leaf 0x14 with ECX == 0. 2. Add PTWRITE detection to CPU feature tests. 3. Add 2 static CPU feature tests.
* manual: Correct description of ENTRY [BZ #17183]Florian Weimer2021-02-041-11/+15
| | | | | | | | The struct tag is actually entry (not ENTRY). The data member has type void *, and it can point to binary data. Only the key member is required to be a null-terminated string. Reviewed-by: Arjun Shankar <arjun@redhat.com>
* sysconf: Add _SC_MINSIGSTKSZ/_SC_SIGSTKSZ [BZ #20305]H.J. Lu2021-02-012-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add _SC_MINSIGSTKSZ for the minimum signal stack size derived from AT_MINSIGSTKSZ, which is the minimum number of bytes of free stack space required in order to gurantee successful, non-nested handling of a single signal whose handler is an empty function, and _SC_SIGSTKSZ which is the suggested minimum number of bytes of stack space required for a signal stack. If AT_MINSIGSTKSZ isn't available, sysconf (_SC_MINSIGSTKSZ) returns MINSIGSTKSZ. On Linux/x86 with XSAVE, the signal frame used by kernel is composed of the following areas and laid out as: ------------------------------ | alignment padding | ------------------------------ | xsave buffer | ------------------------------ | fsave header (32-bit only) | ------------------------------ | siginfo + ucontext | ------------------------------ Compute AT_MINSIGSTKSZ value as size of xsave buffer + size of fsave header (32-bit only) + size of siginfo and ucontext + alignment padding. If _SC_SIGSTKSZ_SOURCE or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ are redefined as /* Default stack size for a signal handler: sysconf (SC_SIGSTKSZ). */ # undef SIGSTKSZ # define SIGSTKSZ sysconf (_SC_SIGSTKSZ) /* Minimum stack size for a signal handler: SIGSTKSZ. */ # undef MINSIGSTKSZ # define MINSIGSTKSZ SIGSTKSZ Compilation will fail if the source assumes constant MINSIGSTKSZ or SIGSTKSZ. The reason for not simply increasing the kernel's MINSIGSTKSZ #define (apart from the fact that it is rarely used, due to glibc's shadowing definitions) was that userspace binaries will have baked in the old value of the constant and may be making assumptions about it. For example, the type (char [MINSIGSTKSZ]) changes if this #define changes. This could be a problem if an newly built library tries to memcpy() or dump such an object defined by and old binary. Bounds-checking and the stack sizes passed to things like sigaltstack() and makecontext() could similarly go wrong.
* Update INSTALL with package versions that are known to workTulio Magno Quites Machado Filho2021-01-251-12/+12
| | | | | | | Most packages have been tested with their latest releases, except for Python, whose latest version is 3.9.1. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* manual: Correct argument order in mount examples [BZ #27207]John McCabe2021-01-221-2/+2
| | | | Reviewed-by: DJ Delorie <dj@redhat.com>
* <sys/platform/x86.h>: Remove the C preprocessor magicH.J. Lu2021-01-211-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In <sys/platform/x86.h>, define CPU features as enum instead of using the C preprocessor magic to make it easier to wrap this functionality in other languages. Move the C preprocessor magic to internal header for better GCC codegen when more than one features are checked in a single expression as in x86-64 dl-hwcaps-subdirs.c. 1. Rename COMMON_CPUID_INDEX_XXX to CPUID_INDEX_XXX. 2. Move CPUID_INDEX_MAX to sysdeps/x86/include/cpu-features.h. 3. Remove struct cpu_features and __x86_get_cpu_features from <sys/platform/x86.h>. 4. Add __x86_get_cpuid_feature_leaf to <sys/platform/x86.h> and put it in libc. 5. Make __get_cpu_features() private to glibc. 6. Replace __x86_get_cpu_features(N) with __get_cpu_features(). 7. Add _dl_x86_get_cpu_features to GLIBC_PRIVATE. 8. Use a single enum index for each CPU feature detection. 9. Pass the CPUID feature leaf to __x86_get_cpuid_feature_leaf. 10. Return zero struct cpuid_feature for the older glibc binary with a smaller CPUID_INDEX_MAX [BZ #27104]. 11. Inside glibc, use the C preprocessor magic so that cpu_features data can be loaded just once leading to more compact code for glibc. 256 bits are used for each CPUID leaf. Some leaves only contain a few features. We can add exceptions to such leaves. But it will increase code sizes and it is harder to provide backward/forward compatibilities when new features are added to such leaves in the future. When new leaves are added, _rtld_global_ro offsets will change which leads to race condition during in-place updates. We may avoid in-place updates by 1. Rename the old glibc. 2. Install the new glibc. 3. Remove the old glibc. NB: A function, __x86_get_cpuid_feature_leaf , is used to avoid the copy relocation issue with IFUNC resolver as shown in IFUNC resolver tests.
* ld.so: Add --list-tunables to print tunable valuesH.J. Lu2021-01-151-0/+38
| | | | | | Pass --list-tunables to ld.so to print tunables with min and max values. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Sync FDL from https://www.gnu.org/licenses/fdl-1.3.texiPaul Eggert2021-01-021-3/+3
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* Update copyright dates with scripts/update-copyrightsPaul Eggert2021-01-0248-48/+48
| | | | | | | | | | | | | | | | 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
* Introduce _FORTIFY_SOURCE=3Siddhesh Poyarekar2020-12-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce a new _FORTIFY_SOURCE level of 3 to enable additional fortifications that may have a noticeable performance impact, allowing more fortification coverage at the cost of some performance. With llvm 9.0 or later, this will replace the use of __builtin_object_size with __builtin_dynamic_object_size. __builtin_dynamic_object_size ----------------------------- __builtin_dynamic_object_size is an LLVM builtin that is similar to __builtin_object_size. In addition to what __builtin_object_size does, i.e. replace the builtin call with a constant object size, __builtin_dynamic_object_size will replace the call site with an expression that evaluates to the object size, thus expanding its applicability. In practice, __builtin_dynamic_object_size evaluates these expressions through malloc/calloc calls that it can associate with the object being evaluated. A simple motivating example is below; -D_FORTIFY_SOURCE=2 would miss this and emit memcpy, but -D_FORTIFY_SOURCE=3 with the help of __builtin_dynamic_object_size is able to emit __memcpy_chk with the allocation size expression passed into the function: void *copy_obj (const void *src, size_t alloc, size_t copysize) { void *obj = malloc (alloc); memcpy (obj, src, copysize); return obj; } Limitations ----------- If the object was allocated elsewhere that the compiler cannot see, or if it was allocated in the function with a function that the compiler does not recognize as an allocator then __builtin_dynamic_object_size also returns -1. Further, the expression used to compute object size may be non-trivial and may potentially incur a noticeable performance impact. These fortifications are hence enabled at a new _FORTIFY_SOURCE level to allow developers to make a choice on the tradeoff according to their environment.
* free: preserve errno [BZ#17924]Paul Eggert2020-12-291-0/+9
| | | | | | | | | | | In the next release of POSIX, free must preserve errno <https://www.austingroupbugs.net/view.php?id=385>. Modify __libc_free to save and restore errno, so that any internal munmap etc. syscalls do not disturb the caller's errno. Add a test malloc/tst-free-errno.c (almost all by Bruno Haible), and document that free preserves errno. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* <sys/platform/x86.h>: Add Intel LAM supportH.J. Lu2020-12-221-0/+3
| | | | | | | | Add Intel Linear Address Masking (LAM) support to <sys/platform/x86.h>. HAS_CPU_FEATURE (LAM) can be used to detect if LAM is enabled in CPU. LAM modifies the checking that is applied to 64-bit linear addresses, allowing software to use of the untranslated address bits for metadata.
* elf: Add a tunable to control use of tagged memoryRichard Earnshaw2020-12-211-0/+35
| | | | | | | | | | | Add a new glibc tunable: mem.tagging. This is a decimal constant in the range 0-255 but used as a bit-field. Bit 0 enables use of tagged memory in the malloc family of functions. Bit 1 enables precise faulting of tag failure on platforms where this can be controlled. Other bits are currently unused, but if set will cause memory tag checking for the current process to be enabled in the kernel.
* config: Allow memory tagging to be enabled when configuring glibcRichard Earnshaw2020-12-211-0/+13
| | | | | | | | This patch adds the configuration machinery to allow memory tagging to be enabled from the command line via the configure option --enable-memory-tagging. The current default is off, though in time we may change that once the API is more stable.
* ieee754: Remove unused __sin32 and __cos32Anssi Hannula2020-12-181-14/+0
| | | | | The __sin32 and __cos32 functions were only used in the now removed slow path of asin and acos.
* s390x: Require GCC 7.1 or later to build glibc.Stefan Liebler2020-12-171-0/+2
| | | | | | | | | | | | | | | | | | | | | | | GCC 6.5 fails to correctly build ldconfig with recent ld.so.cache commits, e.g.: 785969a047ad2f23f758901c6816422573544453 elf: Implement a string table for ldconfig, with tail merging If glibc is build with gcc 6.5.0: __builtin_add_overflow is used in <glibc>/elf/stringtable.c:stringtable_finalize() which leads to ldconfig failing with "String table is too large". This is also recognizable in following tests: FAIL: elf/tst-glibc-hwcaps-cache FAIL: elf/tst-glibc-hwcaps-prepend-cache FAIL: elf/tst-ldconfig-X FAIL: elf/tst-ldconfig-bad-aux-cache FAIL: elf/tst-ldconfig-ld_so_conf-update FAIL: elf/tst-stringtable See gcc "Bug 98269 - gcc 6.5.0 __builtin_add_overflow() with small uint32_t values incorrectly detects overflow" (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98269)
* manual: Clarify File Access Modes section and add O_PATHFlorian Weimer2020-12-031-28/+44
| | | | | | Kees Cook reported that the current text is misleading: <https://lore.kernel.org/lkml/202005150847.2B1ED8F81@keescook/>
* nptl: Return EINVAL for invalid clock for pthread_clockjoin_npAdhemerval Zanella2020-11-251-0/+2
| | | | | | | | | 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>
* Argument Syntax: Use "option", @option, and @command.Carlos O'Donell2020-10-301-6/+6
| | | | Suggested-by: David O'Brien <daobrien@redhat.com>
* Reword description of SXID_* tunable propertiesSiddhesh Poyarekar2020-10-221-5/+6
| | | | | | | | | | | | | The SXID_* tunable properties only influence processes that are AT_SECURE, so make that a bit more explicit in the documentation and comment. Revisiting the code after a few years I managed to confuse myself, so I imagine there could be others who may have incorrectly assumed like I did that the SXID_ERASE tunables are not inherited by children of non-AT_SECURE processes. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* Move vtimes to a compatibility symbolAdhemerval Zanella2020-10-191-61/+0
| | | | | | | | | | | | | | I couldn't pinpoint which standard has added it, but no other POSIX system supports it and/or no longer provide it. The 'struct vtimes' also has a lot of drawbacks due its limited internal type size. I couldn't also see find any project that actually uses this symbol, either in some dignostic way (such as sanitizer). So I think it should be safer to just move to compat symbol, instead of deprecated. The idea it to avoid new ports to export such broken interface (riscv32 for instance). Checked on x86_64-linux-gnu and i686-linux-gnu.
* manual: correct the spelling of "MALLOC_PERTURB_" [BZ #23015]Benno Schulenberg2020-10-131-1/+1
| | | | Reported-by: Martin Dorey <martin.dorey@hds.com>
* manual: replace an obsolete collation example with a valid oneBenno Schulenberg2020-10-131-3/+3
| | | | | | | | | | | | | In the Spanish language, the digraph "ll" has not been considered a separate letter since 1994: https://www.rae.es/consultas/exclusion-de-ch-y-ll-del-abecedario Since January 1998 (commit 49891c106244888123557fca7fddda4fa1f96b1d), glibc's locale data no longer specifies "ch" and "ll" as separate collation elements. So, it's better to not use "ll" in an example. Also, the Czech "ch" is a better example as it collates in a more surprising place.
* <sys/platform/x86.h>: Add FSRCS/FSRS/FZLRM supportH.J. Lu2020-10-091-0/+9
| | | | | Add Fast Short REP CMP and SCA (FSRCS), Fast Short REP STO (FSRS) and Fast Zero-Length REP MOV (FZLRM) support to <sys/platform/x86.h>.
* <sys/platform/x86.h>: Add Intel HRESET supportH.J. Lu2020-10-091-0/+3
| | | | Add Intel HRESET support to <sys/platform/x86.h>.
* <sys/platform/x86.h>: Add AVX-VNNI supportH.J. Lu2020-10-091-0/+3
| | | | Add AVX-VNNI support to <sys/platform/x86.h>.
* <sys/platform/x86.h>: Add AVX512_FP16 supportH.J. Lu2020-10-091-0/+3
| | | | Add AVX512_FP16 support to <sys/platform/x86.h>.
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