This patch updates sysdeps/unix/sysv/linux/syscall-names.list for
Linux 4.18. The io_pgetevents and rseq syscalls are added to the
kernel on various architectures, so need to be mentioned in this file.
Tested with build-many-glibcs.py.
* sysdeps/unix/sysv/linux/syscall-names.list: Update kernel
version to 4.18.
(io_pgetevents): New syscall.
(rseq): Likewise.
Continuing moving macros out of math-tests.h to smaller headers
following typo-proof conventions instead of using #ifndef, this patch
moves the SNAN_TESTS_* macros for individual types out to their own
sysdeps header (while the type-generic SNAN_TESTS wrapper for those
macros remains in math-tests.h).
Tested for x86_64 and x86, and with build-many-glibcs.py.
* sysdeps/generic/math-tests-snan.h: New file.
* sysdeps/generic/math-tests.h: Include <math-tests-snan.h>.
(SNAN_TESTS_float): Do not define here.
(SNAN_TESTS_double): Likewise.
(SNAN_TESTS_long_double): Likewise.
(SNAN_TESTS_float128): Likewise.
* sysdeps/i386/fpu/math-tests-snan.h: New file.
* sysdeps/i386/fpu/math-tests.h: Remove file.
* sysdeps/ia64/math-tests-snan.h: New file.
* sysdeps/ia64/math-tests.h: Remove file.
* sysdeps/x86/math-tests.h: Likewise.
* sysdeps/x86_64/fpu/math-tests-snan.h: New file.
This patch is a complete rewrite of sincosf. The new version is
significantly faster, as well as simple and accurate.
The worst-case ULP is 0.5607, maximum relative error is 0.5303 * 2^-23 over
all 4 billion inputs. In non-nearest rounding modes the error is 1ULP.
The algorithm uses 3 main cases: small inputs which don't need argument
reduction, small inputs which need a simple range reduction and large inputs
requiring complex range reduction. The code uses approximate integer
comparisons to quickly decide between these cases.
The small range reducer uses a single reduction step to handle values up to
120.0. It is fastest on targets which support inlined round instructions.
The large range reducer uses integer arithmetic for simplicity. It does a
32x96 bit multiply to compute a 64-bit modulo result. This is more than
accurate enough to handle the worst-case cancellation for values close to
an integer multiple of PI/4. It could be further optimized, however it is
already much faster than necessary.
sincosf throughput gains on Cortex-A72:
* |x| < 0x1p-12 : 1.6x
* |x| < M_PI_4 : 1.7x
* |x| < 2 * M_PI: 1.5x
* |x| < 120.0 : 1.8x
* |x| < Inf : 2.3x
* math/Makefile: Add s_sincosf_data.c.
* sysdeps/ia64/fpu/s_sincosf_data.c: New file.
* sysdeps/ieee754/flt-32/s_sincosf.h (abstop12): Add new function.
(sincosf_poly): Likewise.
(reduce_small): Likewise.
(reduce_large): Likewise.
* sysdeps/ieee754/flt-32/s_sincosf.c (sincosf): Rewrite.
* sysdeps/ieee754/flt-32/s_sincosf_data.c: New file with sincosf data.
* sysdeps/m68k/m680x0/fpu/s_sincosf_data.c: New file.
* sysdeps/x86_64/fpu/s_sincosf_data.c: New file.
This patch currently only affects aarch64.
The roundtoint and converttoint internal functions are only called with small
values, so 32 bit result is enough for converttoint and it is a signed int
conversion so the return type is changed to int32_t.
The original idea was to help the compiler keeping the result in uint64_t,
then it's clear that no sign extension is needed and there is no accidental
undefined or implementation defined signed int arithmetics.
But it turns out gcc does a good job with inlining so changing the type has
no overhead and the semantics of the conversion is less surprising this way.
Since we want to allow the asuint64 (x + 0x1.8p52) style conversion, the top
bits were never usable and the existing code ensures that only the bottom
32 bits of the conversion result are used.
On aarch64 the neon intrinsics (which round ties to even) are changed to
round and lround (which round ties away from zero) this does not affect the
results in a significant way, but more portable (relies on round and lround
being inlined which works with -fno-math-errno).
The TOINT_SHIFT and TOINT_RINT macros were removed, only keep separate code
paths for TOINT_INTRINSICS and !TOINT_INTRINSICS.
* sysdeps/aarch64/fpu/math_private.h (roundtoint): Use round.
(converttoint): Use lround.
* sysdeps/ieee754/flt-32/math_config.h (roundtoint): Declare and
document the semantics when TOINT_INTRINSICS is set.
(converttoint): Likewise.
(TOINT_RINT): Remove.
(TOINT_SHIFT): Remove.
* sysdeps/ieee754/flt-32/e_expf.c (__expf): Remove the TOINT_RINT code
path.
Commit 298d0e3129 ("Consolidate Linux
getdents{64} implementation") broke the implementation because it does
not take into account struct offset differences.
The new implementation is close to the old one, before the
consolidation, but has been cleaned up slightly.
* Since __fentry__ is almost the same as _mcount, reuse the code by
#including it twice with different #defines around.
* Remove LA usages - they are needed in 31-bit mode to clear the top
bit, but in 64-bit they appear to do nothing.
* Add CFI rule for the nonstandard return register. This rule applies
to the current function (binutils generates a new CIE - see
gas/dw2gencfi.c:select_cie_for_fde()), so it is not necessary to put
__fentry__ into a new file.
* Fix CFI offset for %r14.
* Add CFI rule for %r0.
* Fix unwound value of %r15 being off by 244 bytes.
* Unwinding in __fentry__@plt does not work, no plan to fix it - it
would require asking linker to generate CFI for return address in
%r0. From functional perspective keeping it broken is fine, since
the callee did not have a chance to do anything yet. From
convenience perspective it would be possible to enhance GDB in the
future to treat __fentry__@plt in a special way.
* Fix whitespace.
* Fix offsets in comments, which were copied from 32-bit code.
* 32-bit version will not be implemented, since it's not compatible
with the corresponding PLT stubs: they assume %r12 points to GOT,
which is not the case for gcc-emitted __fentry__ stub, which runs
before the prolog.
This patch adds the runtime support in glibc for the -mfentry
gcc feature introduced in [1] and [2].
[1] https://gcc.gnu.org/ml/gcc-patches/2018-07/msg00784.html
[2] https://gcc.gnu.org/ml/gcc-patches/2018-07/msg00912.html
ChangeLog:
* sysdeps/s390/s390-64/Versions (__fentry__): Add.
* sysdeps/s390/s390-64/s390x-mcount.S: Move the common
code to s390x-mcount.h and #include it.
* sysdeps/s390/s390-64/s390x-mcount.h: New file.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
(__fentry__): Add.
__fentry__ symbol is currently not defined for other architectures.
Attempts to introduce it cause abicheck to fail, because it will be
available since 2.29 earliest, and not 2.13, which is the case for
Intel. With the new code, abicheck passes for i686-linux-gnu,
x86_64-linux-gnu and x86_64-linux-gnu32 triples.
ChangeLog:
* stdlib/Versions: Remove __fentry__.
* sysdeps/i386/Versions: Add __fentry__.
* sysdeps/x86_64/Versions: Add __fentry__.
The following combinations need to be tested:
* 32- (g5, esa and zarch) and 64-bit
* linux32 glibc/configure CC='gcc -m31 -march=g5'
* linux32 glibc/configure CC='gcc -m31'
* linux32 glibc/configure CC='gcc -m31 -mzarch'
* With and without VX:
* glibc/configure libc_cv_asm_s390_vx=no
* With and without profiling (using LD_PROFILE)
* With and without pltexit (using LD_AUDIT)
ChangeLog:
* sysdeps/s390/Makefile: Register the new tests.
* sysdeps/s390/tst-dl-runtime-mod.S: New file.
* sysdeps/s390/tst-dl-runtime-profile-audit.c: New file.
* sysdeps/s390/tst-dl-runtime-profile-noaudit.c: New file.
* sysdeps/s390/tst-dl-runtime-resolve-audit.c: New file.
* sysdeps/s390/tst-dl-runtime-resolve-noaudit.c: New file.
* sysdeps/s390/tst-dl-runtime.c: New file.
Following the recent discussion of using Python instead of Perl and
Awk for glibc build / test, this patch replaces gen-libm-test.pl with
a new gen-libm-test.py script. This script should work with all
Python versions supported by glibc (tested by hand with Python 2.7,
tested in the build system with Python 3.5; configure prefers Python 3
if available).
This script is designed to give identical output to gen-libm-test.pl
for ease of verification of the change, except for generated comments
referring to .py instead of .pl. (That is, identical for actual
inputs passed to the script, not necessarily for all possible input;
for example, this version more precisely follows the C standard syntax
for floating-point constants when deciding when to add LIT macro
calls.) In one place a comment notes that the generation of
NON_FINITE flags is replicating a bug in the Perl script to assist in
such comparisons (with the expectation that this bug can then be
separately fixed in the Python script later).
Tested for x86_64, including comparison of generated files (and hand
testing of the case of generating a sorted libm-test-ulps file, which
isn't covered by normal "make check").
I'd expect to follow this up by extending the new script to produce
the ulps tables for the manual as well (replacing
manual/libm-err-tab.pl, so that then we just have one ulps file
parser) - at which point the manual build would depend on both Perl
and Python (eliminating the Perl dependency would require someone to
rewrite summary.pl in Python, and that would only eliminate the
*direct* Perl dependency; current makeinfo is written in Perl so there
would still be an indirect dependency).
I think install.texi is more or less equally out-of-date regarding
Perl and Python uses before and after this patch, so I don't think
this patch depends on my patch
<https://sourceware.org/ml/libc-alpha/2018-08/msg00133.html> to update
install.texi regarding such uses (pending review).
* math/gen-libm-test.py: New file.
* math/gen-libm-test.pl: Remove.
* math/Makefile [$(PERL) != no]: Change condition to [PYTHON].
($(objpfx)libm-test-ulps.h): Use gen-libm-test.py instead of
gen-libm-test.pl.
($(libm-test-c-noauto-obj)): Likewise.
($(libm-test-c-auto-obj)): Likewise.
($(libm-test-c-narrow-obj)): Likewise.
(regen-ulps): Likewise.
* math/README.libm-test: Update references to gen-libm-test.pl.
* math/libm-test-driver.c (struct test_fj_f_data): Update comment
referencing gen-libm-test.pl.
* math/libm-test-nexttoward.inc (nexttoward_test_data): Likewise.
* math/libm-test-support.c: Likewise.
* math/libm-test-support.h: Likewise.
* sysdeps/generic/libm-test-ulps: Likewise.
MIN_PAGE_SIZE is normally set to 4096 but for testing it can be set to
16 so that it exercises the page crossing code for every misaligned
access. The value was set to 15, which is obviously wrong, so fixed
as obvious and tested.
* sysdeps/aarch64/strlen.S [TEST_PAGE_CROSS](MIN_PAGE_SIZE):
Fix value.
Since RISC-V stores the thread pointer in a general register libthread_db
can just ask the debugger for the register contents instead of trying to
call ps_get_thread_area. This enables thread debugging in gdb.
* sysdeps/riscv/nptl/tls.h (DB_THREAD_SELF): Use REGISTER instead
of CONST_THREAD_AREA.
Move STATE_SAVE_OFFSET and STATE_SAVE_MASK to sysdep.h to make
sysdeps/x86/cpu-features.h a C header file.
* sysdeps/x86/cpu-features.h (STATE_SAVE_OFFSET): Removed.
(STATE_SAVE_MASK): Likewise.
Don't check __ASSEMBLER__ to include <cpu-features-offsets.h>.
* sysdeps/x86/sysdep.h (STATE_SAVE_OFFSET): New.
(STATE_SAVE_MASK): Likewise.
* sysdeps/x86_64/dl-trampoline.S: Include <cpu-features-offsets.h>
instead of <cpu-features.h>.
* sysdeps/riscv/rv64/rvd/libm-test-ulps: Update.
Note: I regen'd these from scratch, but I'm only committing the
increases, as I only tested on hardware. There were a few 2->1
decreases that I omitted, possibly "for now".
* sysdeps/riscv/rvf/math_private.h (libc_feholdexcept_setround_riscv):
Fix rounding save-restore bug.
Fixes about a hundred off-by-ULP failures in the math testsuite.
There is no need to include <init-arch.h> in assembly codes since all
x86 IFUNC selector functions are written in C. Tested on i686 and
x86-64. There is no code change in libc.so, ld.so and libmvec.so.
* sysdeps/i386/i686/multiarch/bzero-ia32.S: Don't include
<init-arch.h>.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin8_core-avx2.S: Likewise.
* sysdeps/x86_64/fpu/multiarch/svml_s_expf16_core-avx2.S: Likewise.
* sysdeps/x86_64/multiarch/memset-sse2-unaligned-erms.S: Likewise.
The glibc.tune namespace is vaguely named since it is a 'tunable', so
give it a more specific name that describes what it refers to. Rename
the tunable namespace to 'cpu' to more accurately reflect what it
encompasses. Also rename glibc.tune.cpu to glibc.cpu.name since
glibc.cpu.cpu is weird.
* NEWS: Mention the change.
* elf/dl-tunables.list: Rename tune namespace to cpu.
* sysdeps/powerpc/dl-tunables.list: Likewise.
* sysdeps/x86/dl-tunables.list: Likewise.
* sysdeps/aarch64/dl-tunables.list: Rename tune.cpu to
cpu.name.
* elf/dl-hwcaps.c (_dl_important_hwcaps): Adjust.
* elf/dl-hwcaps.h (GET_HWCAP_MASK): Likewise.
* manual/README.tunables: Likewise.
* manual/tunables.texi: Likewise.
* sysdeps/powerpc/cpu-features.c: Likewise.
* sysdeps/unix/sysv/linux/aarch64/cpu-features.c
(init_cpu_features): Likewise.
* sysdeps/x86/cpu-features.c: Likewise.
* sysdeps/x86/cpu-features.h: Likewise.
* sysdeps/x86/cpu-tunables.c: Likewise.
* sysdeps/x86_64/Makefile: Likewise.
* sysdeps/x86/dl-cet.c: Likewise.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
MIPS soft-float glibc does not support floating-point exceptions and
rounding modes, and uses a different ABI from hard-float so a
soft-float compilation cannot use a glibc that does support
floating-point exceptions and rounding modes. Thus, bits/fenv.h
should not, when compiling for soft-float, define macros for the
unsupported features.
This patch changes it accordingly to define those macros only for
hard-float. None of the exception macros are defined for soft-float,
with FE_ALL_EXCEPT defined to 0 in that case, and only FE_TONEAREST is
defined of the rounding-mode macros, and FE_NOMASK_ENV is not defined;
this is consistent with how architectures lacking exception and
rounding mode support generally define things in this header. As well
as making the header more correct for this case, this also means the
generic math_private.h optimizations for this case automatically apply
(inlining libm-internal fenv.h function calls that are trivial when
exceptions and rounding modes are not supported).
The mips64 sfp-machine.h then needs similar changes to disable more of
the exception and rounding mode handling for soft-float. (The mips32
sfp-machine.h is already used only for soft-float, has no integration
with hardware exceptions or rounding modes and so needs no changes.)
Existing binaries might use the old FE_NOMASK_ENV value as an argument
to fesetenv / feupdateenv and expect an error for it (given that it
was defined in a header that also defined FE_ALL_EXCEPT to a nonzero
value). To preserve that error, wrappers for the fallback fesetenv
and feupdateenv are created in sysdeps/mips/nofpu/.
Tested for mips64 (hard-float and soft-float, all three ABIs).
[BZ #23479]
* sysdeps/mips/bits/fenv.h (FE_INEXACT): Define only if
[__mips_hard_float].
(FE_UNDERFLOW): Likewise.
(FE_OVERFLOW): Likewise.
(FE_DIVBYZERO): Likewise.
(FE_INVALID): Likewise.
(FE_ALL_EXCEPT): Define to 0 if [!__mips_hard_float].
(FE_TOWARDZERO): Define only if [__mips_hard_float].
(FE_UPWARD): Likewise.
(FE_DOWNWARD): Likewise.
(__FE_UNDEFINED): Define if [!__mips_hard_float]
(FE_NOMASK_ENV): Define only if [__mips_hard_float].
* sysdeps/mips/mips64/sfp-machine.h (_FP_DECL_EX): Define only if
[__mips_hard_float].
(FP_ROUNDMODE): Likewise.
(FP_RND_NEAREST): Likewise.
(FP_RND_ZERO): Likewise.
(FP_RND_PINF): Likewise.
(FP_RND_MINF): Likewise.
(FP_EX_INVALID): Likewise.
(FP_EX_OVERFLOW): Likewise.
(FP_EX_UNDERFLOW): Likewise.
(FP_EX_DIVZERO): Likewise.
(FP_EX_INEXACT): Likewise.
(FP_INIT_ROUNDMODE): Likewise.
* sysdeps/mips/nofpu/fesetenv.c: New file.
* sysdeps/mips/nofpu/feupdateenv.c: Likewise.
Continuing moving macros out of math-tests.h to smaller headers
following typo-proof conventions instead of using #ifndef, this patch
moves SNAN_TESTS_PRESERVE_PAYLOAD out to its own sysdeps header.
Tested with build-many-glibcs.py.
* sysdeps/generic/math-tests-snan-payload.h: New file.
* sysdeps/hppa/math-tests-snan-payload.h: Likewise.
* sysdeps/mips/math-tests-snan-payload.h: Likewise.
* sysdeps/riscv/math-tests-snan-payload.h: Likewise.
* sysdeps/generic/math-tests.h: Include
<math-tests-snan-payload.h>.
(SNAN_TESTS_PRESERVE_PAYLOAD): Do not define macro here.
* sysdeps/hppa/math-tests.h: Remove file.
* sysdeps/mips/math-tests.h [!__mips_nan2008]
(SNAN_TESTS_PRESERVE_PAYLOAD): Do not define macro here.
* sysdeps/riscv/math-tests.h (SNAN_TESTS_PRESERVE_PAYLOAD):
Likewise.
The math-tests.h header has many different macros and groups of
macros, defined using #ifndef in the generic version which is included
by architecture versions with #include_next after possibly defining
non-default versions of some of those macros.
This use of #ifndef is contrary to our normal typo-proof conventions
for macro definitions. This patch moves one of the macros,
SNAN_TESTS_TYPE_CAST, out to its own sysdeps header, to follow those
typo-proof conventions more closely.
Tested with build-many-glibcs.py.
2018-08-01 Joseph Myers <joseph@codesourcery.com>
* sysdeps/generic/math-tests-snan-cast.h: New file.
* sysdeps/powerpc/math-tests-snan-cast.h: Likewise.
* sysdeps/generic/math-tests.h: Include <math-tests-snan-cast.h>.
(SNAN_TESTS_TYPE_CAST): Do not define macro here.
* sysdeps/powerpc/math-tests.h (SNAN_TESTS_TYPE_CAST): Likewise.
Exec needs that mach_setup_thread does *not* set up TLS since it works on
another task, so we have to split this into mach_setup_tls.
* mach/mach.h (__mach_setup_tls, mach_setup_tls): Add prototypes.
* mach/setup-thread.c (__mach_setup_thread): Move TLS setup to...
(__mach_setup_tls): ... new function.
(mach_setup_tls): New alias.
* hurd/hurdsig.c (_hurdsig_init): Call __mach_setup_tls after
__mach_setup_thread.
* sysdeps/mach/hurd/profil.c (update_waiter): Likewise.
* sysdeps/mach/hurd/setitimer.c (setitimer_locked): Likewise.
* mach/Versions [libc] (mach_setup_tls): Add symbol.
* sysdeps/mach/hurd/i386/libc.abilist (mach_setup_tls): Likewise.
GNU_PROPERTY_X86_FEATURE_1_AND may not be the first property item. We
need to check each property item until we reach the end of the property
or find GNU_PROPERTY_X86_FEATURE_1_AND.
This patch adds 2 tests. The first test checks if IBT is enabled and
the second test reads the output from the first test to check if IBT
is is enabled. The second second test fails if IBT isn't enabled
properly.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
[BZ #23467]
* sysdeps/unix/sysv/linux/x86/Makefile (tests): Add
tst-cet-property-1 and tst-cet-property-2 if CET is enabled.
(CFLAGS-tst-cet-property-1.o): New.
(ASFLAGS-tst-cet-property-dep-2.o): Likewise.
($(objpfx)tst-cet-property-2): Likewise.
($(objpfx)tst-cet-property-2.out): Likewise.
* sysdeps/unix/sysv/linux/x86/tst-cet-property-1.c: New file.
* sysdeps/unix/sysv/linux/x86/tst-cet-property-2.c: Likewise.
* sysdeps/unix/sysv/linux/x86/tst-cet-property-dep-2.S: Likewise.
* sysdeps/x86/dl-prop.h (_dl_process_cet_property_note): Parse
each property item until GNU_PROPERTY_X86_FEATURE_1_AND is found.
All tests should be added to $(tests).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
[BZ #23458]
* sysdeps/x86/Makefile (tests): Add tst-get-cpu-features-static.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
* sysdeps/mach/hurd/not-errno.h: New file.
* sysdeps/mach/hurd/i386/localplt.data: Update accordingly.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
* sysdeps/mach/hurd/dl-unistd.h (__access, __brk, __lseek, __read,
__sbrk): Do not set attribute_hidden.
* sysdeps/mach/hurd/i386/ld.abilist: Update accordingly.
* sysdeps/mach/hurd/i386/localplt.data: Update accordingly.
Simply check if "ptr < ptr_end" since "ptr" is always incremented by 8.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* sysdeps/x86/dl-prop.h (_dl_process_cet_property_note): Don't
parse beyond the note end.
This patch make the OFD tests return unsupported if kernel does not
support OFD locks (it was added on 3.15).
Checked on a ia64-linux-gnu with Linux 3.14.
* sysdeps/unix/sysv/linux/tst-ofdlocks.c: Return unsupported if
kernel does not support OFD locks.
* sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Likewise.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
More fixes are needed to avoid the hidden attribute.
* sysdeps/mach/hurd/Versions (libc): Make __access and
__access_noerrno external so they can override the ld symbols.
(ld): Make __access, __read, __sbrk, __strtoul_internal, __write,
__writev, __open64, __access_noerrno extern so they can be overrided.
* sysdeps/mach/hurd/i386/libc.abilist: Update accordingly.
* sysdeps/mach/hurd/i386/ld.abilist: Update accordingly.
cpu-features.h has
#define bit_cpu_LZCNT (1 << 5)
#define index_cpu_LZCNT COMMON_CPUID_INDEX_1
#define reg_LZCNT
But the LZCNT feature bit is in COMMON_CPUID_INDEX_80000001:
Initial EAX Value: 80000001H
ECX Extended Processor Signature and Feature Bits:
Bit 05: LZCNT available
index_cpu_LZCNT should be COMMON_CPUID_INDEX_80000001, not
COMMON_CPUID_INDEX_1. The VMX feature bit is in COMMON_CPUID_INDEX_1:
Initial EAX Value: 01H
Feature Information Returned in the ECX Register:
5 VMX
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
[BZ # 23456]
* sysdeps/x86/cpu-features.h (index_cpu_LZCNT): Set to
COMMON_CPUID_INDEX_80000001.
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.
Verify that setcontext works with gaps above and below the newly
allocated shadow stack.
* sysdeps/unix/sysv/linux/x86/Makefile (tests): Add
tst-cet-setcontext-1 if CET is enabled.
(CFLAGS-tst-cet-setcontext-1.c): Add -mshstk.
* sysdeps/unix/sysv/linux/x86/tst-cet-setcontext-1.c: New file.
Remove conformace assumption of NPTL implementation for ISO C threads
and revert wrong libcrypt addition on linknamespace-libs-XPG4.
The i686-gnu target now shows two new conformance failures:
FAIL: conform/ISO11/threads.h/conform
FAIL: conform/ISO11/threads.h/linknamespace
It is expected due missing HTL ISO C threads support and both conformance
.out files indicates the reason ("#error "HTL does not implement ISO C
threads").
Checked on i686-linux-gnu and i686-gnu.
* include/threads.h: Move to ...
* sysdeps/nptl/threads.h: ... here.
* sysdeps/htl/threads.h: New file.
* conform/Makefile (linknamespace-libs-ISO11): Use
static-thread-library instead of linking libpthread.
(linknamespace-libs-XPG4): Revert wrong libcrypt.a addition.
This patch adds a field to ucontext_t to save shadow stack:
1. getcontext and swapcontext are updated to save the caller's shadow
stack pointer and return addresses.
2. setcontext and swapcontext are updated to restore shadow stack and
jump to new context directly.
3. makecontext is updated to allocate a new shadow stack and set the
caller's return address to __start_context.
Since makecontext allocates a new shadow stack when making a new
context and kernel allocates a new shadow stack for clone/fork/vfork
syscalls, we track the current shadow stack base. In setcontext and
swapcontext, if the target shadow stack base is the same as the current
shadow stack base, we unwind the shadow stack. Otherwise it is a stack
switch and we look for a restore token.
We enable shadow stack at run-time only if program and all used shared
objects, including dlopened ones, are shadow stack enabled, which means
that they must be compiled with GCC 8 or above and glibc 2.28 or above.
We need to save and restore shadow stack only if shadow stack is enabled.
When caller of getcontext, setcontext, swapcontext and makecontext is
compiled with smaller ucontext_t, shadow stack won't be enabled at
run-time. We check if shadow stack is enabled before accessing the
extended field in ucontext_t.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* sysdeps/unix/sysv/linux/x86/sys/ucontext.h (ucontext_t): Add
__ssp.
* sysdeps/unix/sysv/linux/x86_64/__start_context.S: Include
<asm/prctl.h> and "ucontext_i.h" when shadow stack is enabled.
(__push___start_context): New.
* sysdeps/unix/sysv/linux/x86_64/getcontext.S: Include
<asm/prctl.h>.
(__getcontext): Record the current shadow stack base. Save the
caller's shadow stack pointer and base.
* sysdeps/unix/sysv/linux/x86_64/makecontext.c: Include
<pthread.h>, <libc-pointer-arith.h> and <sys/prctl.h>.
(__push___start_context): New prototype.
(__makecontext): Call __push___start_context to allocate a new
shadow stack, push __start_context onto the new stack as well
as the new shadow stack.
* sysdeps/unix/sysv/linux/x86_64/setcontext.S: Include
<asm/prctl.h>.
(__setcontext): Restore the target shadow stack.
* sysdeps/unix/sysv/linux/x86_64/swapcontext.S: Include
<asm/prctl.h>.
(__swapcontext): Record the current shadow stack base. Save
the caller's shadow stack pointer and base. Restore the target
shadow stack.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h
(STACK_SIZE_TO_SHADOW_STACK_SIZE_SHIFT): New.
* sysdeps/unix/sysv/linux/x86_64/ucontext_i.sym (oSSP): New.
