Commit Graph

36666 Commits

Author SHA1 Message Date
Joseph Myers
1c426b1d59 Update STATX_ATTR_DAX value from Linux 5.10.
This patch updates the value of STATX_ATTR_DAX in bits/statx-generic.h
for a change made in Linux 5.10.  (As with previous such changes, this
only does anything if glibc is being used with old kernel headers.)

Tested for x86_64.
2021-01-11 14:57:08 +00:00
Vincent Chen
313bfd505e riscv: Initialize $gp before resolving the IRELATIVE relocation
The $gp register may be used to access the global variable in
the PDE program, so the $gp register should be initialized before
executing the IFUNC resolver of PDE program to avoid unexpected
error occurs.
2021-01-10 21:25:16 -05:00
Vincent Chen
c31b1f5231 riscv: support GNU indirect function
Enable riscv glibc to support GNU indirect function
2021-01-10 21:25:13 -05:00
Martin Sebor
2cd361b511 posix: Correct attribute access mode on readlinkat [BZ #27024]. 2021-01-10 13:45:39 -07:00
Alexandra Hájková
7a72265436 Add xfchmod to libsupport 2021-01-10 18:55:47 +01:00
Alexandra Hájková
a7e9dbb774 Add xchdir to libsupport. 2021-01-09 17:47:50 +01:00
Marc Aurèle La France
c6e2ca2c3f POSIX locale: Fix typo in comment 2021-01-09 12:14:44 +01:00
Vineet Gupta
1b5c9dfeb2 ARC: Regenerate ulps
Reinstate pass for

FAIL: math/test-double-cosh
FAIL: math/test-double-sinh
FAIL: math/test-float32x-cosh
FAIL: math/test-float32x-sinh
FAIL: math/test-float64-cosh
FAIL: math/test-float64-sinh
FAIL: math/test-ldouble-cosh
FAIL: math/test-ldouble-sinh
2021-01-08 09:48:24 -08:00
Siddhesh Poyarekar
eeaa19f75e mntent: Use __putc_unlocked instead of fputc_unlocked
__putc_unlocked is guaranteed to be inlined all the time as opposed to
fputc_unlocked, which does not get inlined when glibc is built with
-Os.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-01-08 21:02:12 +05:30
Szabolcs Nagy
2f056e8a5d aarch64: define PI_STATIC_AND_HIDDEN
AArch64 always uses pc relative access to static and hidden object
symbols, but the config setting was previously missing.

This affects ld.so start up code.
2021-01-08 11:14:02 +00:00
Siddhesh Poyarekar
18b640c570 Update NEWS for CVE-2019-25013. 2021-01-08 09:20:29 +05:30
H.J. Lu
ecce11aa07 x86: Support GNU_PROPERTY_X86_ISA_1_V[234] marker [BZ #26717]
GCC 11 supports -march=x86-64-v[234] to enable x86 micro-architecture ISA
levels:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97250

and -mneeded to emit GNU_PROPERTY_X86_ISA_1_NEEDED property with
GNU_PROPERTY_X86_ISA_1_V[234] marker:

https://gitlab.com/x86-psABIs/x86-64-ABI/-/merge_requests/13

Binutils support for GNU_PROPERTY_X86_ISA_1_V[234] marker were added by

commit b0ab06937385e0ae25cebf1991787d64f439bf12
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Oct 30 06:49:57 2020 -0700

    x86: Support GNU_PROPERTY_X86_ISA_1_BASELINE marker

and

commit 32930e4edbc06bc6f10c435dbcc63131715df678
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Oct 9 05:05:57 2020 -0700

    x86: Support GNU_PROPERTY_X86_ISA_1_V[234] marker

GNU_PROPERTY_X86_ISA_1_NEEDED property in x86 ELF binaries indicate the
micro-architecture ISA level required to execute the binary.  The marker
must be added by programmers explicitly in one of 3 ways:

1. Pass -mneeded to GCC.
2. Add the marker in the linker inputs as this patch does.
3. Pass -z x86-64-v[234] to the linker.

Add GNU_PROPERTY_X86_ISA_1_BASELINE and GNU_PROPERTY_X86_ISA_1_V[234]
marker support to ld.so if binutils 2.32 or newer is used to build glibc:

1. Add GNU_PROPERTY_X86_ISA_1_BASELINE and GNU_PROPERTY_X86_ISA_1_V[234]
markers to elf.h.
2. Add GNU_PROPERTY_X86_ISA_1_BASELINE and GNU_PROPERTY_X86_ISA_1_V[234]
marker to abi-note.o based on the ISA level used to compile abi-note.o,
assuming that the same ISA level is used to compile the whole glibc.
3. Add isa_1 to cpu_features to record the supported x86 ISA level.
4. Rename _dl_process_cet_property_note to _dl_process_property_note and
add GNU_PROPERTY_X86_ISA_1_V[234] marker detection.
5. Update _rtld_main_check and _dl_open_check to check loaded objects
with the incompatible ISA level.
6. Add a testcase to verify that dlopen an x86-64-v4 shared object fails
on lesser platforms.
7. Use <get-isa-level.h> in dl-hwcaps-subdirs.c and tst-glibc-hwcaps.c.

Tested under i686, x32 and x86-64 modes on x86-64-v2, x86-64-v3 and
x86-64-v4 machines.

Marked elf/tst-isa-level-1 with x86-64-v4, ran it on x86-64-v3 machine
and got:

[hjl@gnu-cfl-2 build-x86_64-linux]$ ./elf/tst-isa-level-1
./elf/tst-isa-level-1: CPU ISA level is lower than required
[hjl@gnu-cfl-2 build-x86_64-linux]$
2021-01-07 13:10:13 -08:00
Wilco Dijkstra
9e97f239ea Remove dbl-64/wordsize-64 (part 2)
Remove the wordsize-64 implementations by merging them into the main dbl-64
directory.  The second patch just moves all wordsize-64 files and removes a
few wordsize-64 uses in comments and Implies files.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-01-07 15:26:26 +00:00
Wilco Dijkstra
caa884dda7 Remove dbl-64/wordsize-64
Remove the wordsize-64 implementations by merging them into the main dbl-64
directory.  The first patch adds special cases needed for 32-bit targets
(FIX_INT_FP_CONVERT_ZERO and FIX_DBL_LONG_CONVERT_OVERFLOW) to the
wordsize-64 versions.  This has no effect on 64-bit targets since they don't
define these macros.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-01-07 15:02:51 +00:00
Joseph Myers
3016596a81 Add SEGV_MTEAERR and SEGV_MTESERR from Linux 5.10.
Linux 5.10 adds constants SEGV_MTEAERR and SEGV_MTESERR to
asm-generic/siginfo.h.  Add these to glibc's bits/siginfo-consts.h.

Tested for x86_64.
2021-01-06 18:23:00 +00:00
Adhemerval Zanella
ecdb06cdf2 support: Add support_small_thread_stack_size
It returns the minimum stack size large enough to cover most internal
glibc stack usage.
2021-01-05 11:33:16 -03:00
Adhemerval Zanella
c6e0b0b5b0 stdlib: Sync canonicalize with gnulib [BZ #10635] [BZ #26592] [BZ #26341] [BZ #24970]
It sync with gnulib version ae9fb3d66.  The testcase for BZ#23741
(stdlib/test-bz22786.c) is adjusted to check also for ENOMEM.

The patch fixes multiple realpath issues:

  - Portability fixes for errno clobbering on free (BZ#10635).  The
    function does not call free directly anymore, although it might be
    done through scratch_buffer_free.  The free errno clobbering is
    being tracked by BZ#17924.

  - Pointer arithmetic overflows in realpath (BZ#26592).

  - Realpath cyclically call __alloca(path_max) to consume too much
    stack space (BZ#26341).

  - Realpath mishandles EOVERFLOW; stat not needed anyway (BZ#24970).
    The check is done through faccessat now.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2021-01-05 11:33:16 -03:00
Adhemerval Zanella
448a256359 malloc: Add scratch_buffer_dupfree
It returns a copy of the buffer up to a defined size.  It will be used
on realpath sync with gnulib.
2021-01-05 11:33:16 -03:00
Adhemerval Zanella
47f4316095 Import filename.h from gnulib
And use to simplify stdlib/canonicalize.c implementation.
2021-01-05 11:33:16 -03:00
Adhemerval Zanella
ef8c78a6c6 Import idx.h from gnulib
And use to simplify stdlib/canonicalize.c implementation.
2021-01-05 11:33:16 -03:00
Adhemerval Zanella
6cc992412c alpha: Provide wait4 for static library [BZ #27150]
This ia regression from 09153638cf, versioned_symbol acts as
weak_alias for !SHARED but it is undefined to avoid non versioned
alias from the generic implementation.

Checked with a build for alpha-linux-gnu.
2021-01-05 11:22:25 -03:00
Shuo Wang
f5082c7010 aarch64: push the set of rules before falling into slow path
It is supposed to save the rules for the instructions before falling into slow path.

Tested in glibc-2.28 before fixing:
Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
149		stp	x1,  x2, [sp, #-32]!
Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
150		stp	x3,  x4, [sp, #16]
(gdb)
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
157		mrs	x4, tpidr_el0
(gdb)
158		ldr	PTR_REG (1), [x0,#TLSDESC_ARG]
(gdb)
159		ldr	PTR_REG (0), [x4,#TCBHEAD_DTV]
(gdb)
160		ldr	PTR_REG (3), [x1,#TLSDESC_GEN_COUNT]
(gdb)
161		ldr	PTR_REG (2), [x0,#DTV_COUNTER]
(gdb)
162		cmp	PTR_REG (3), PTR_REG (2)
(gdb)
163		b.hi	2f
(gdb)
165		ldp	PTR_REG (2), PTR_REG (3), [x1,#TLSDESC_MODID]
(gdb)
166		add	PTR_REG (0), PTR_REG (0), PTR_REG (2), lsl #(PTR_LOG_SIZE + 1)
(gdb)
167		ldr	PTR_REG (0), [x0] /* Load val member of DTV entry.  */
(gdb)
168		cmp	PTR_REG (0), #TLS_DTV_UNALLOCATED
(gdb)
169		b.eq	2f
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:169
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=4294967295)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:184
184		stp	x29, x30, [sp,#-16*NSAVEXREGPAIRS]!
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:184
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=4294967295)
    at /home/test/test_function.c:30
#2  0x0000000000000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Co-authored-by: liqingqing <liqingqing3@huawei.com>
2021-01-05 09:25:19 +00:00
Jangwoong Kim
c50c65a8bf nptl: Fix comment typo in pthread_cond_wait.c 2021-01-04 22:09:35 +01:00
H.J. Lu
6ea5b57afa x86: Check IFUNC definition in unrelocated executable [BZ #20019]
Calling an IFUNC function defined in unrelocated executable also leads to
segfault.  Issue a fatal error message when calling IFUNC function defined
in the unrelocated executable from a shared library.
2021-01-04 12:01:01 -08:00
Samuel Thibault
b47b07c92d hurd: Fix mmap(!MAP_FIXED) on bogus address
In the !MAP_FIXED case, when a bogus address is given mmap should pick up a
valide address rather than returning EINVAL: Posix only talks about
EINVAL for the MAP_FIXED case.

This fixes long-running ghc processes.
2021-01-04 20:22:59 +01:00
H.J. Lu
3ec5d83d2a x86-64: Avoid rep movsb with short distance [BZ #27130]
When copying with "rep movsb", if the distance between source and
destination is N*4GB + [1..63] with N >= 0, performance may be very
slow.  This patch updates memmove-vec-unaligned-erms.S for AVX and
AVX512 versions with the distance in RCX:

	cmpl	$63, %ecx
	// Don't use "rep movsb" if ECX <= 63
	jbe	L(Don't use rep movsb")
	Use "rep movsb"

Benchtests data with bench-memcpy, bench-memcpy-large, bench-memcpy-random
and bench-memcpy-walk on Skylake, Ice Lake and Tiger Lake show that its
performance impact is within noise range as "rep movsb" is only used for
data size >= 4KB.
2021-01-04 07:58:57 -08:00
Shuo Wang
cd6274089f aarch64: fix stack missing after sp is updated
After sp is updated, the CFA offset should be set before next instruction.
Tested in glibc-2.28:
Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
149		stp	x1,  x2, [sp, #-32]!
Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
150		stp	x3,  x4, [sp, #16]
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
157		mrs	x4, tpidr_el0
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78

Signed-off-by: liqingqing <liqingqing3@huawei.com>
Signed-off-by: Shuo Wang <wangshuo47@huawei.com>
2021-01-04 15:37:06 +00:00
Florian Weimer
f5a6f846b0 nptl: Remove set*id, set*gid files which are not built 2021-01-04 16:27:46 +01:00
Siddhesh Poyarekar
8cc1e39a36 Drop nan-pseudo-number.h usage from tests
Make the tests use TEST_COND_intel96 to decide on whether to build the
unnormal tests instead of the macro in nan-pseudo-number.h and then
drop the header inclusion.  This unbreaks test runs on all
architectures that do not have ldbl-96.

Also drop the HANDLE_PSEUDO_NUMBERS macro since it is not used
anywhere.
2021-01-04 20:49:56 +05:30
Adhemerval Zanella
252864544a posix: Sync fnmatch with gnulib
It sync with gnulib commit 43ee1a6bf.

Checked on x86_64-linux-gnu.
2021-01-04 09:02:39 -03:00
Adhemerval Zanella
9c774ad764 Sync flexmember.h with gnulib
It sync with gnulib commit 43ee1a6bf.
2021-01-04 08:42:25 -03:00
Adhemerval Zanella
11b2858bd1 Sync intprops.h with gnulib
It sync with gnulib commit 43ee1a6bf.

Checked on x86_64-linux-gnu.
2021-01-04 08:42:04 -03:00
Adhemerval Zanella
4883360415 posix: Sync glob code with gnulib
It sync with gnulib commit 43ee1a6bf and fixes and use-after-free
bug (gnulib commit 717766da8926e36).

Checked on x86_64-linux-gnu.
2021-01-04 08:41:53 -03:00
Adhemerval Zanella
c2a150d089 posix: Sync regex code with gnulib
It sync with gnulib commit 43ee1a6bf.  The main change is 9682f18e9.
(which does not have a meaniful description).

Checked on x86_64-linux-gnu.
2021-01-04 08:38:52 -03:00
Siddhesh Poyarekar
fee3b889d8 Move generic nan-pseudo-number.h to ldbl-96
The concept of pseudo number formats only exists in the realm of the
96 bit long double format.
2021-01-04 14:51:52 +05:30
Paul Eggert
21c3f4b536 Sync FDL from https://www.gnu.org/licenses/fdl-1.3.texi 2021-01-02 12:46:25 -08:00
Paul Eggert
ba74122538 Sync move-if-change from Gnulib
This alters move-if-change so that its --version option outputs
the correct copyright date automatically.  One less thing
to update by hand.
2021-01-02 12:43:58 -08:00
Paul Eggert
82cfac84c7 Update automatically-generated copyright dates
These were updated simply by running "make" to regen the files.
2021-01-02 12:17:34 -08:00
Paul Eggert
9fcdec7386 Update copyright dates not handled by scripts/update-copyrights.
I've updated copyright dates in glibc for 2021.  This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files.  As well as the usual annual
updates, mainly dates in --version output (minus csu/version.c which
previously had to be handled manually but is now successfully updated
by update-copyrights), there is a small change to the copyright notice
in NEWS which should let NEWS get updated automatically next year.

Please remember to include 2021 in the dates for any new files added
in future (which means updating any existing uncommitted patches you
have that add new files to use the new copyright dates in them).
2021-01-02 12:17:34 -08:00
Paul Eggert
2b778ceb40 Update copyright dates with scripts/update-copyrights
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
2021-01-02 12:17:34 -08:00
Szabolcs Nagy
45b1e17e91 aarch64: use PTR_ARG and SIZE_ARG instead of DELOUSE
DELOUSE was added to asm code to make them compatible with non-LP64
ABIs, but it is an unfortunate name and the code was not compatible
with ABIs where pointer and size_t are different. Glibc currently
only supports the LP64 ABI so these macros are not really needed or
tested, but for now the name is changed to be more meaningful instead
of removing them completely.

Some DELOUSE macros were dropped: clone, strlen and strnlen used it
unnecessarily.

The out of tree ILP32 patches are currently not maintained and will
likely need a rework to rebase them on top of the time64 changes.
2020-12-31 16:50:58 +00:00
Siddhesh Poyarekar
f9de8bfe1a nonstring: Enable __FORTIFY_LEVEL=3
Use __builtin_dynamic_object_size in the remaining functions that
don't have compiler builtins as is the case for string functions.
2020-12-31 16:55:21 +05:30
Siddhesh Poyarekar
2a3224c536 string: Enable __FORTIFY_LEVEL=3
This change enhances fortified string functions to use
__builtin_dynamic_object_size under _FORTIFY_SOURCE=3 whenever the
compiler supports it.
2020-12-31 16:55:21 +05:30
Siddhesh Poyarekar
c43c579612 Introduce _FORTIFY_SOURCE=3
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.
2020-12-31 16:55:21 +05:30
Siddhesh Poyarekar
2a08b6e833 Warn on unsupported fortification levels
Make the _FORTIFY_SOURCE macro soup in features.h warn about
unsupported fortification levels.  For example, it will warn about
_FORTIFY_SOURCE=3 and over with an indication of which level has been
selected.

Co-authored-by: Paul Eggert <eggert@cs.ucla.edu>
2020-12-31 16:55:21 +05:30
Matheus Castanho
41f013cef2 powerpc: Use scv instruction on clone when available
clone already uses r31 to temporarily save input arguments before doing the
syscall, so we use a different register to read from the TCB. We can also avoid
allocating another stack frame, which is not needed since we can simply extend
the usage of the red zone.

Tested-by: Lucas A. M. Magalhães <lamm@linux.ibm.com>
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
2020-12-30 18:26:33 -03:00
Matheus Castanho
68ab82f566 powerpc: Runtime selection between sc and scv for syscalls
Linux kernel v5.9 added support for system calls using the scv
instruction for POWER9 and later.  The new codepath provides better
performance (see below) if compared to using sc.  For the
foreseeable future, both sc and scv mechanisms will co-exist, so this
patch enables glibc to do a runtime check and use scv when it is
available.

Before issuing the system call to the kernel, we check hwcap2 in the TCB
for PPC_FEATURE2_SCV to see if scv is supported by the kernel.  If not,
we fallback to sc and keep the old behavior.

The kernel implements a different error return convention for scv, so
when returning from a system call we need to handle the return value
differently depending on the instruction we used to enter the kernel.

For syscalls implemented in ASM, entry and exit are implemented by
different macros (PSEUDO and PSEUDO_RET, resp.), which may be used in
sequence (e.g. for templated syscalls) or with other instructions in
between (e.g. clone).  To avoid accessing the TCB a second time on
PSEUDO_RET to check which instruction we used, the value read from
hwcap2 is cached on a non-volatile register.

This is not needed when using INTERNAL_SYSCALL macro, since entry and
exit are bundled into the same inline asm directive.

The dynamic loader may issue syscalls before the TCB has been setup
so it always uses sc with no extra checks.  For the static case, there
is no compile-time way to determine if we are inside startup code,
so we also check the value of the thread pointer before effectively
accessing the TCB.  For such situations in which the availability of
scv cannot be determined, sc is always used.

Support for scv in syscalls implemented in their own ASM file (clone and
vfork) will be added later. For now simply use sc as before.

Average performance over 1M calls for each syscall "type":
  - stat: C wrapper calling INTERNAL_SYSCALL
  - getpid: templated ASM syscall
  - syscall: call to gettid using syscall function

  Standard:
     stat : 1.573445 us / ~3619 cycles
   getpid : 0.164986 us / ~379 cycles
  syscall : 0.162743 us / ~374 cycles

  With scv:
     stat : 1.537049 us / ~3535 cycles <~ -84 cycles  / -2.32%
   getpid : 0.109923 us / ~253 cycles  <~ -126 cycles / -33.25%
  syscall : 0.116410 us / ~268 cycles  <~ -106 cycles / -28.34%

Tested on powerpc, powerpc64, powerpc64le (with and without scv)

Tested-by: Lucas A. M. Magalhães <lamm@linux.ibm.com>
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
2020-12-30 18:26:25 -03:00
Adhemerval Zanella
9835632cf4 malloc: preserve errno on mcheck hooks [BZ #17924]
Similar to the fix 69fda43b8d, save and restore errno for the hook
functions used for MALLOC_CHECK_=3.

It fixes the malloc/tst-free-errno-mcheck regression.

Checked on x86_64-linux-gnu.
2020-12-30 10:37:58 -03:00
Siddhesh Poyarekar
38a033ac85 x86 long double: Add tests for pseudo normal numbers
Add some tests for fpclassify, isnan, isinf and issignaling.

Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-12-30 10:53:11 +05:30
Siddhesh Poyarekar
7525c1c71d x86 long double: Consider pseudo numbers as signaling
Add support to treat pseudo-numbers specially and implement x86
version to consider all of them as signaling.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-12-30 10:52:45 +05:30