Joseph Myers [Mon, 14 Oct 2019 23:43:52 +0000 (23:43 +0000)]
Add PTRACE_GET_SYSCALL_INFO from Linux 5.3 to sys/ptrace.h.
Linux 5.3 adds a PTRACE_GET_SYSCALL_INFO constant, with an associated
structure and PTRACE_SYSCALL_INFO_* constants.
This patch adds these to sys/ptrace.h in glibc
(PTRACE_GET_SYSCALL_INFO in each architecture version, the rest in
bits/ptrace-shared.h). As with previous such constants and associated
structures, the glibc version of the structure is named struct
__ptrace_syscall_info.
Instead the release manager is expected to generate a ChangeLog-like
file using scripts/gitlog_to_changelog.py. For further details,
see commit f2144b7874b23be7c7eb184ec601633ec6fa8fac ("Script to
generate ChangeLog-like output from git log").
Florian Weimer [Fri, 11 Oct 2019 18:15:24 +0000 (20:15 +0200)]
manual: Remove warning in the documentation of the abort function
The warning is confusing to those who do not understand the context,
and the warning is easy to misunderstand:
A reader needs to know that it was written by someone who is generally
skeptical of government influence and control, otherwise it reads as
an affirmation of the U.S. government's role as the ultimate editor of
the manual. This is precisely the opposite of what the warning
intends to convey. (Reportedly, it criticizes that several
U.S. administrations have tried to restrict the medical advice that
U.S.-funded health care workers can provide abroad, considering that
censorship.)
The warning is also misleading on a technical level. A reader who
makes the connection to pregnancy termination will get the wrong
impression that calling the abort function will terminate subprocesses
of the current process, but this is not what generally happens.
Finally, for both GNU and the FSF, it is inappropriate to use female
reproductive health as mere joke material, since these organizations
do not concern themselves with such issues otherwise, and the warning
is purportedly about something else entirely.
This patch sets the mode field in ipc_perm as mode_t for all architectures,
as POSIX specification [1]. The changes required are as follow:
1. It moves the ipc_perm definition out of ipc.h to its own header
ipc_perm.h. It also allows consolidate the IPC_* definition on
only one header.
2. The generic implementation follow the kernel ipc64_perm size so the
syscall can be made directly without temporary buffer copy. However,
since glibc defines the MODE field as mode_t, it omits the __PAD1 field
(since glibc does not export mode_t as 16-bit for any architecture).
It is a two-fold improvement:
2.1. New implementation which follow Linux UAPI will not need to
provide an arch-specific ipc-perm.h header neither wrongly
use the wrong 16-bit definition from previous default ipc.h
(as csky did).
2.1. It allows consolidate ipc_perm definition for architectures that
already provide mode_t as 32-bit.
3. All kernel ABIs for the supported architectures already provides the
expected padding for mode type extension to 32-bit. However, some
architectures the padding has the wrong placement, so it requires
the ipc control routines (msgctl, semctl, and shmctl) to adjust the
mode field accordingly. Currently they are armeb, microblaze, m68k,
s390, and sheb.
A new assume is added, __ASSUME_SYSVIPC_BROKEN_MODE_T, which the
required ABIs define.
4. For the ABIs that define __ASSUME_SYSVIPC_BROKEN_MODE_T, it also
require compat symbols that do not adjust the mode field.
Checked on arm-linux-gnueabihf, aarch64-linux-gnu, powerpc64le-linux-gnu,
and x86_64-linux-gnu. I also checked the sysvipc tests on hppa-linux-gnu,
sh4-linux-gnu, s390x-linux-gnu, and s390-linux-gnu.
I also did a sanity test against armeb qemu usermode for the sysvipc
tests.
y2038: linux: Provide __clock_settime64 implementation
This patch provides new __clock_settime64 explicit 64 bit function for
setting the time. Moreover, a 32 bit version - __clock_settime - has been
refactored to internally use __clock_settime64.
The __clock_settime is now supposed to be used on systems still supporting
32 bit time (__TIMESIZE != 64) - hence the necessary conversion to 64 bit
struct timespec.
The new clock_settime64 syscall available from Linux 5.1+ has been used,
when applicable.
In this patch the internal padding (tv_pad) of struct __timespec64 is
left untouched (on systems with __WORDSIZE == 32) as Linux kernel ignores
upper 32 bits of tv_nsec.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with clock_settime64) and glibc build with v5.1 as minimal
kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports
__clock_settime64 syscalls.
- Linux v4.19 (no clock_settime64 support) with default minimal kernel
version for contemporary glibc
This kernel doesn't support __clock_settime64 syscalls, so the fallback
to clock_settime is tested.
The above tests were performed with Y2038 redirection applied as well as
without (so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
* include/time.h (__clock_settime64):
Add __clock_settime alias according to __TIMESIZE define
* sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime):
Refactor this function to be used only on 32 bit machines as a wrapper
on __clock_settime64.
* sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime64): Add
* sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime64):
Use clock_settime64 kernel syscall (available from 5.1+ Linux)
This patch replaces the fork+exec by posix_spawn on wordexp, which
allows a better scability on Linux and simplifies the thread
cancellation handling.
The only change which can not be implemented with posix_spawn the
/dev/null check to certify it is indeed the expected device. I am
not sure how effetive this check is since /dev/null tampering means
something very wrong with the system and this is the least of the
issues. My view is the tests is really out of the place and the
hardening provided is minimum.
If the idea is still to provide such check, I think a possibilty
would be to open /dev/null, check it, add a dup2 file action, and
close the file descriptor.
Checked on powerpc64le-linux-gnu and x86_64-linux-gnu.
* include/spawn.h (__posix_spawn_file_actions_addopen): New
prototype.
* posix/spawn_faction_addopen.c (posix_spawn_file_actions_addopen):
Add internal alias.
* posix/wordexp.c (create_environment, free_environment): New
functions.
(exec_comm_child, exec_comm): Use posix_spawn instead of fork+exec.
* posix/wordexp-test.c: Use libsupport.
This patch changes how the fallback getdents64 implementation calls
non-LFS getdents by replacing the scratch_buffer with static buffer
plus a loop on getdents calls. This avoids the potential malloc
call on scratch_buffer_set_array_size for large input buffer size
at the cost of more getdents syscalls.
It also adds a small optimization for older kernels, where the first
ENOSYS failure for getdents64 disable subsequent calls.
Check the dirent tests on a mips64-linux-gnu with getdents64 code
disabled.
* sysdeps/unix/sysv/linux/mips/mips64/getdents64.c (__getdents64):
Add small optimization for older kernel to avoid issuing
__NR_getdents64 on each call and replace scratch_buffer usage with
a static allocated buffer.
Make tst-strftime2 and tst-strftime3 depend on locale generation
Building the test cases in parallel might make tst-strftime2 and
tst-strftime3 fail. Simply re-running the test case (or building
serially) makes the problem go away. This patch adds the necessary
dependency to allow parallel builds in the time subdirectory.
Tested for powerpc64le.
Reviewed-by: Florian Weimer <fweimer@redhat.com> Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Florian Weimer [Tue, 8 Oct 2019 11:04:15 +0000 (13:04 +0200)]
wordexp: Split out command execution tests from posix/wordexp-test
Once wordexp switches to posix_spawn, testing for command execution
based on fork handlers will not work anymore. Therefore, move these
subtests into a new test, posix/tst-wordexp-nocmd, which uses a
different form of command execution detection, based on PID
namespaces.
Florian Weimer [Mon, 7 Oct 2019 17:03:50 +0000 (19:03 +0200)]
riscv: Remove support for variable page sizes
_dl_var_init is used to patch the read-only data section after
relocation. Several architectures use this to update
GLRO(page_size) with the correct value for the static dlopen case,
where _rtld_global_ro has not been initialized by the dynamic
loader.
RISC-V does not need this. The RISC-V Instruction Set Manual,
Volume II: Privileged Architecture, Document Version 20190608-Priv-MSU-Ratified says this:
After much deliberation, we have settled on a conventional
page size of 4 KiB for both RV32 and RV64. We expect this
decision to ease the porting of low-level runtime software
and device drivers. The TLB reach problem is ameliorated by
transparent superpage support in modern operating systems
[2]. Additionally, multi-level TLB hierarchies are quite
inexpensive relative to the multi-level cache hierarchies
whose address space they map.
[2] Juan Navarro, Sitaram Iyer, Peter Druschel, and
Alan Cox. Practical, transparent operating system support
for superpages. SIGOPS Oper. Syst. Rev., 36(SI):89–104,
December 2002.
This means that the initialization of
_rtld_global_ro._dl_page_size in elf/rtld.c with EXEC_PAGESIZE
is sufficient for RISC-V.
Florian Weimer [Fri, 4 Oct 2019 19:23:51 +0000 (21:23 +0200)]
elf: Assign TLS modid later during dlopen [BZ #24930]
Commit a42faf59d6d9f82e5293a9ebcc26d9c9e562b12b ("Fix BZ #16634.")
attempted to fix a TLS modid consistency issue by adding additional
checks to the open_verify function. However, this is fragile
because open_verify cannot reliably predict whether
_dl_map_object_from_fd will later fail in the more complex cases
(such as memory allocation failures). Therefore, this commit
assigns the TLS modid as late as possible. At that point, the link
map pointer will eventually be passed to _dl_close, which will undo
the TLS modid assignment.
Reviewed-by: Gabriel F. T. Gomes <gabrielftg@linux.ibm.com>
Florian Weimer [Fri, 4 Oct 2019 19:22:54 +0000 (21:22 +0200)]
elf: Never use the file ID of the main executable [BZ #24900]
If the loader is invoked explicitly and loads the main executable,
it stores the file ID of the main executable in l_file_id. This
information is not available if the main excutable is loaded by the
kernel, so this is another case where the two cases differ.
Joseph Myers [Wed, 2 Oct 2019 21:12:17 +0000 (21:12 +0000)]
Disable -Wmaybe-uninitialized for total_deadline in sunrpc/clnt_udp.c.
To work around <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91691>
for RV32, we recently disabled -Wmaybe-uninitialized for some inline
functions in inet/net-internal.h, as included by sunrpc/clnt_udp.c.
The same error has now appeared with current GCC trunk for MIPS, in a
form that is located at the definition of the variable in question and
so unaffected by the disabling in inet/net-internal.h. Thus, this
patch adds the same disabling around the definition of that variable,
to cover the MIPS case.
Tested with build-many-glibcs.py (compilers and glibcs stages) for
mips64-linux-gnu with GCC mainline.
* sunrpc/clnt_udp.c: Include <libc-diag.h>.
(clntudp_call): Disable -Wmaybe-uninitialized around declaration
of total_deadline.
string/endian.h: Restore the __USE_MISC conditionals
Commit 69fd157a3 "time: Add padding for the timespec if required"
caused a breakage in the glibc tests as the endian.h include file was
kept in the networking headers while the __USE_MISC #ifdefs had been
removed. This resulted in namespace violations in the networking
headers.
This patche restores the __USE_MISC conditionals in endian.h to fix the
test failures.
* string/endian.h: Restore the __USE_MISC conditionals.
Joseph Myers [Wed, 2 Oct 2019 17:26:14 +0000 (17:26 +0000)]
Disable warnings in string/tester.c at top level.
string/tester.c contains code that correctly triggers various GCC
warnings about dubious uses of string functions (uses that are being
deliberately tested there), and duly disables those warnings around
the relevant code.
A change in GCC mainline resulted in this code failing to compile with
a -Warray-bounds error, despite the location with the error having
-Warray-bounds already disabled. This has been reported as
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91890>. This patch
avoids that problem and possible future issues with these diagnostics
by moving all the warning disabling in this file to top level, as
suggested by Florian in
<https://sourceware.org/ml/libc-alpha/2019-10/msg00033.html>, rather
than only doing it locally around specific function calls.
Tested with build-many-glibcs.py for aarch64-linux-gnu with GCC
mainline (with only the conform/ failures noted in
<https://sourceware.org/ml/libc-alpha/2019-10/msg00043.html>).
* string/tester.c: Ignore -Warray-bounds and
-Wmemset-transposed-args at top level.
[__GNUC_PREREQ (7, 0)]: Ignore -Wrestrict and -Wstringop-overflow=
at top level.
[__GNUC_PREREQ (8, 0)]: Ignore -Wstringop-truncation at top level.
(test_stpncpy): Do not ignore warnings here.
(test_strncat): Likewise.
(test_strncpy): Likewise.
(test_memset): Likewise.
Lukasz Majewski [Wed, 2 Oct 2019 08:19:55 +0000 (10:19 +0200)]
Y2038: Include proper header to provide support for struct timeval on HURD
The HURD requires explicit inclusion of <bits/types/struct_timeval.h> to use
struct timeval in ./include/time.h.
For this particular glibc port, the proper header hasn't been included before
inclusion of time.h.
Tested with build-many-glibcs.py with i686-gnu and x86_64-linux-gnu:
build-many-glibcs.py /home/lukma/work/glibc/glibc-many-build --keep all compilers i686-gnu
build-many-glibcs.py /home/lukma/work/glibc/glibc-many-build --keep all glibcs i686-gnu
Also run of xcheck on x86_64:
./src/configure --prefix=/usr
make PARALLELMFLAGS="-j12" && make xcheck PARALLELMFLAGS="-j12"
Paul A. Clarke [Thu, 19 Sep 2019 16:11:04 +0000 (11:11 -0500)]
[powerpc] No need to enter "Ignore Exceptions Mode"
Since at least POWER8, there is no performance advantage to entering
"Ignore Exceptions Mode", and doing so conditionally requires
- the conditional logic, and
- a system call.
Arjun Shankar [Wed, 2 Oct 2019 11:59:43 +0000 (13:59 +0200)]
Enable passing arguments to the inferior in debugglibc.sh
This patch adds the ability to run debugglibc.sh's inferior program with
arguments specified on the command line. This enables convenient debugging
of non-testcase programs such as iconv/iconv_prog or other dynamically
linked programs. Program arguments may be passed using `--' as a separator.
Alistair Francis [Wed, 18 Sep 2019 23:51:23 +0000 (16:51 -0700)]
time: Add padding for the timespec if required
If we are running on a 32-bit system with a 64-bit time_t we need to
ensure there is padding around the tv_nsec variable. This is requried as
the timespec is #defined to the __timespec64 struct.
* time/bits/types/struct_timespec.h: Add padding for the timespec if
required.
Alistair Francis [Fri, 20 Sep 2019 21:23:51 +0000 (14:23 -0700)]
Split up endian.h to minimize exposure of BYTE_ORDER.
With only two exceptions (sys/types.h and sys/param.h, both of which
historically might have defined BYTE_ORDER) the public headers that
include <endian.h> only want to be able to test __BYTE_ORDER against
__*_ENDIAN.
This patch creates a new bits/endian.h that can be included by any
header that wants to be able to test __BYTE_ORDER and/or
__FLOAT_WORD_ORDER against the __*_ENDIAN constants, or needs
__LONG_LONG_PAIR. It only defines macros in the implementation
namespace.
The existing bits/endian.h (which could not be included independently
of endian.h, and only defines __BYTE_ORDER and maybe __FLOAT_WORD_ORDER)
is renamed to bits/endianness.h. I also took the opportunity to
canonicalize the form of this header, which we are stuck with having
one copy of per architecture. Since they are so short, this means git
doesn’t understand that they were renamed from existing headers, sigh.
endian.h itself is a nonstandard header and its only remaining use
from a standard header is guarded by __USE_MISC, so I dropped the
__USE_MISC conditionals from around all of the public-namespace things
it defines. (This means, an application that requests strict library
conformance but includes endian.h will still see the definition of
BYTE_ORDER.)
A few changes to specific bits/endian(ness).h variants deserve
mention:
- sysdeps/unix/sysv/linux/ia64/bits/endian.h is moved to
sysdeps/ia64/bits/endianness.h. If I remember correctly, ia64 did
have selectable endianness, but we have assembly code in
sysdeps/ia64 that assumes it’s little-endian, so there is no reason
to treat the ia64 endianness.h as linux-specific.
- The C-SKY port does not fully support big-endian mode, the compile
will error out if __CSKYBE__ is defined.
- The PowerPC port had extra logic in its bits/endian.h to detect a
broken compiler, which strikes me as unnecessary, so I removed it.
- The only files that defined __FLOAT_WORD_ORDER always defined it to
the same value as __BYTE_ORDER, so I removed those definitions.
The SH bits/endian(ness).h had comments inconsistent with the
actual setting of __FLOAT_WORD_ORDER, which I also removed.
- I *removed* copyright boilerplate from the few bits/endian(ness).h
headers that had it; these files record a single fact in a fashion
dictated by an external spec, so I do not think they are copyrightable.
As long as I was changing every copy of ieee754.h in the tree, I
noticed that only the MIPS variant includes float.h, because it uses
LDBL_MANT_DIG to decide among three different versions of
ieee854_long_double. This patch makes it not include float.h when
GCC’s intrinsic __LDBL_MANT_DIG__ is available.
* string/endian.h: Unconditionally define LITTLE_ENDIAN,
BIG_ENDIAN, PDP_ENDIAN, and BYTE_ORDER. Condition byteswapping
macros only on !__ASSEMBLER__. Move the definitions of
__BIG_ENDIAN, __LITTLE_ENDIAN, __PDP_ENDIAN, __FLOAT_WORD_ORDER,
and __LONG_LONG_PAIR to...
* string/bits/endian.h: ...this new file, which includes
the renamed header bits/endianness.h for the definition of
__BYTE_ORDER and possibly __FLOAT_WORD_ORDER.
* string/Makefile: Install bits/endianness.h.
* include/bits/endian.h: New wrapper.
* bits/endian.h: Rename to bits/endianness.h.
Add multiple-include guard. Rewrite the comment explaining what
the machine-specific variants of this file should do.
* sysdeps/unix/sysv/linux/ia64/bits/endian.h:
Move to sysdeps/ia64.
* sysdeps/unix/sysv/linux/hppa/pthread.h: Don’t include endian.h.
* sysdeps/mips/ieee754/ieee754.h: Use __LDBL_MANT_DIG__
in ifdefs, instead of LDBL_MANT_DIG. Only include float.h
when __LDBL_MANT_DIG__ is not predefined, in which case
define __LDBL_MANT_DIG__ to equal LDBL_MANT_DIG.
Mike FABIAN [Tue, 17 Sep 2019 15:20:32 +0000 (17:20 +0200)]
Sync "language", "lang_name", "territory", "country_name" with CLDR/langtable
Sync these values with CLDR and langtable as much as possible. Add
missing values.
If possible, take the values from CLDR, if CLDR does not have it,
take it from langtable. The values from langtable which are not from
CLDR are from Wikipedia or native speakers.
Lukasz Majewski [Mon, 25 Mar 2019 07:38:02 +0000 (08:38 +0100)]
y2038: Provide conversion helpers for struct __timespec64
Those functions allow easy conversion between Y2038 safe struct
__timespec64 and other time related data structures (like struct timeval
or struct timespec).
Joseph Myers [Mon, 30 Sep 2019 15:49:25 +0000 (15:49 +0000)]
Update bits/mman.h constants and tst-mman-consts.py for Linux 5.3.
The Linux 5.3 uapi headers have some rearrangement relating to MAP_*
constants, which includes the effect of adding definitions of MAP_SYNC
on powerpc and sparc. This patch updates the corresponding glibc
bits/mman.h headers accordingly, and updates the Linux kernel version
number in tst-mman-consts.py to reflect that these constants are now
current with that kernel version.
Tested with build-many-glibcs.py.
* sysdeps/unix/sysv/linux/powerpc/bits/mman.h [__USE_MISC]
(MAP_SYNC): New macro.
* sysdeps/unix/sysv/linux/sparc/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/tst-mman-consts.py (main): Update Linux
kernel version number to 5.3.
This patch adds a new make rule that generates a helper script for
debugging glibc test cases. The new script, debugglibc.sh, is similar
to testrun.sh, in the sense that it allows the execution of the
specified test case, however, it opens the test case in GDB, setting the
library path the same way that testrun.sh does. The commands are based
on the instructions on the wiki for glibc debugging [1,2].
By default, the script tells GDB to load the test case for symbol
information, so that, when a breakpoint is hit, the call stack is
displayed correctly (instead of printing lots of '??'s). For instance,
after running 'make' and 'make check', one could do the following:
$ ./debugglibc.sh nptl/tst-exec1 -b pthread_join
Reading symbols from /home/gabriel/build/powerpc64le/glibc//elf/ld.so...done.
Breakpoint 1 at 0x1444
add symbol table from file "nptl/tst-exec1"
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/home/gabriel/build/powerpc64le/glibc//nptl_db/libthread_db.so.1".
Breakpoint 1, 0x00007ffff7fb1444 in _dl_start_user () from /home/gabriel/build/powerpc64le/glibc/elf/ld.so
Breakpoint 2 at 0x7ffff7f49d48: file pthread_join.c, line 23.
Notice that the script will always start GDB with the program running
and halted at _dl_start_user. So, in order to reach the actual
breakpoint of interest, one should hit 'c', not 'r':
>>> c
Continuing.
[New Thread 0x7ffff7d1f180 (LWP 76443)]
[Switching to Thread 0x7ffff7d1f180 (LWP 76443)]
Thread 2 "ld.so" hit Breakpoint 2, __pthread_join (threadid=140737354087616, thread_return=0x0) at pthread_join.c:24
24 return __pthread_timedjoin_ex (threadid, thread_return, NULL, true);
Then inspect the call stack with 'bt', as usual, and see symbols from
both the test case and from the libraries themselves:
>>> bt
#0 __pthread_join (threadid=140737354087616, thread_return=0x0) at pthread_join.c:24
#1 0x0000000010001f4c in tf (arg=<optimized out>) at tst-exec1.c:37
#2 0x00007ffff7f487e8 in start_thread (arg=0x7ffff7510000) at pthread_create.c:479
#3 0x00007ffff7e523a8 in clone () at ../sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S:82
Reviewed-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Reviewed-by: Joseph Myers <joseph@codesourcery.com> Reviewed-by: Andreas Schwab <schwab@suse.de>
Paul A. Clarke [Thu, 19 Sep 2019 19:04:45 +0000 (14:04 -0500)]
[powerpc] Rename fesetenv_mode to fesetenv_control
fesetenv_mode is used variously to write the FPSCR exception enable
bits and rounding mode bits. These are referred to as the control
bits in the POWER ISA. Change the name to be reflective of its
current and expected use, and match up well with fegetenv_control.
libc_feholdsetround_noex_ppc_ctx currently performs:
1. Read FPSCR, save to context.
2. Create new FPSCR value: clear enables and set new rounding mode.
3. Write new value to FPSCR.
Since other bits just pass through, there is no need to write them.
Instead, write just the changed values (enables and rounding mode),
which can be a bit more efficient.
Paul A. Clarke [Thu, 19 Sep 2019 16:58:46 +0000 (11:58 -0500)]
[powerpc] Rename fegetenv_status to fegetenv_control
fegetenv_status is used variously to retrieve the FPSCR exception enable
bits, rounding mode bits, or both. These are referred to as the control
bits in the POWER ISA. FPSCR status bits are also returned by the
'mffs' and 'mffsl' instructions, but they are uniformly ignored by all
uses of fegetenv_status. Change the name to be reflective of its
current and expected use.
Reviewed-By: Paul E Murphy <murphyp@linux.ibm.com>
Paul A. Clarke [Thu, 19 Sep 2019 16:39:44 +0000 (11:39 -0500)]
[powerpc] __fesetround_inline optimizations
On POWER9, use more efficient means to update the 2-bit rounding mode
via the 'mffscrn' instruction (instead of two 'mtfsb0/1' instructions
or one 'mtfsfi' instruction that modifies 4 bits).
Suggested-by: Paul E. Murphy <murphyp@linux.ibm.com> Reviewed-By: Paul E Murphy <murphyp@linux.ibm.com>
ROUND_TO_ODD and a couple of other places use libc_feupdateenv_test to
restore the rounding mode and exception enables, preserve exception flags,
and test whether given exception(s) were generated.
If the exception flags haven't changed, then it is sufficient and a bit
more efficient to just restore the rounding mode and enables, rather than
writing the full Floating-Point Status and Control Register (FPSCR).
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
Lukasz Majewski [Fri, 22 Mar 2019 10:53:45 +0000 (11:53 +0100)]
y2038: Introduce struct __timespec64 - new internal glibc type
This type is a glibc's "internal" type similar to struct timespec but
whose tv_sec field is a __time64_t rather than a time_t, which makes it
Y2038-proof and usable to pass syscalls between user code and Y2038-proof
kernel.
To support passing this structure to the kernel - the unnamed 32 bit
padding bit-field has been introduced. The placement of it depends on
the endianness of the SoC.
The total_deadline variable inside the clntudp_call() function inside
sunrpc/clnt_udp.c can cause uninitalised variable warnings when building
with GCC 8.3 or 9.2 on a platform with a 64-bit tv_nsec on a 32-bit
architecture. To fix the warning let's use the DIAG_* macros to hide the
warning.
A GCC bug case has also been submitted:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91691
2019-09-24 Alistair Francis <alistair.francis@wdc.com>
Script to generate ChangeLog-like output from git log
Co-authored-by: Gabriel F. T. Gomes <gabriel@inconstante.net.br> Reviewed-by: Gabriel F. T. Gomes <gabriel@inconstante.net.br> Reviewed-by: Joseph Myers <joseph@codesourcery.com>
The utility of a ChangeLog file has been discussed in various mailing
list threads and GNU Tools Cauldrons in the past years and the general
consensus is that while the file may have been very useful in the past
when revision control did not exist or was not as powerful as it is
today, it's current utility is fast diminishing. Further, the
ChangeLog format gets in the way of modernisation of processes since
it almost always results in rewriting of a commit, thus preventing use
of any code review tools to automatically manage patches in the glibc
project.
There is consensus in the glibc community that documentation of why a
change was done (i.e. a detailed description in a git commit) is more
useful than what changed (i.e. a ChangeLog entry) since the latter can
be deduced from the patch. The GNU community would however like to
keep the option of ascertaining what changed through a ChangeLog-like
output and as a compromise, it was proposed that a script be developed
that generates this output.
The script below is the result of these discussions. This script
takes two git revisions references as input and generates the git log
between those revisions in a form that resembles a ChangeLog. Its
capabilities and limitations are listed in a comment in the script.
On a high level it is capable of parsing C code and telling what
changed at the top level, but not within constructs such as functions.
Design
------
At a high level, the script analyses the raw output of a VCS, parses
the source files that have changed and attempts to determine what
changed. The script driver needs three distinct components to be
fully functional for a repository:
- A vcstocl_quirks.py file that helps it parse weird patterns in
sources that may result from preprocessor defines.
- A VCS plugin backend; the git backend is implemented for glibc
- A programming language parser plugin. C is currently implemented.
Additional programming language parsers can be added to give more
detailed output for changes in those types of files.
For input in languages other than those that have a parser, the script
only identifies if a file has been added, removed, modified,
permissions changed, etc. but cannot understand the change in content.
The C Parser
------------
The C parser is capable of parsing C programs with preprocessor macros
in place, as if they were part of the language. This presents some
challenges with parsing code that expands macros on the fly and to
help work around that, a vcstocl_quirks.py file has transformations to
ease things.
The C parser currently can identify macro definitions and scopes and
all global and static declarations and definitions. It cannot parse
(and compare) changes inside functions yet, it could be a future
enhancement if the need for it arises.
Testing
-------
The script has been tested with the glibc repository up to glibc-2.29
and also in the past with emacs. While it would be ideal to have
something like this in a repository like gnulib, that should not be a
bottleneck for glibc to start using this, so this patch proposes to
add these scripts into glibc.
And here is (hopefully!) one of the last ChangeLog entries we'd have
to write for glibc:
* scripts/gitlog_to_changelog.py: New script to auto-generate
ChangeLog.
* scripts/vcs_to_changelog/frontend_c.py: New file.
* scripts/vcs_to_changelog/misc_util.py: New file.
* scripts/vcs_to_changelog/vcs_git.py: New file.
* scripts/vcs_to_changelog/vcstocl_quirks.py: Likewise.
Paul A. Clarke [Thu, 19 Sep 2019 13:35:16 +0000 (08:35 -0500)]
[powerpc] SET_RESTORE_ROUND optimizations and bug fix
SET_RESTORE_ROUND brackets a block of code, temporarily setting and
restoring the rounding mode and letting everything else, including
exceptions generated within the block, pass through.
On powerpc, the current code clears the exception enables, which will hide
exceptions generated within the block. This issue was introduced by me
in commit e905212627350d54b58426214b5a54ddc852b0c9.
Fix this by not clearing exception enable bits in the prologue.
Also, since we are no longer changing the enable bits in either the
prologue or the epilogue, there is no need to test for entering/exiting
non-stop mode.
Also, optimize the prologue get/save/set rounding mode operations for
POWER9 and later by using 'mffscrn' when possible.
Suggested-by: Paul E. Murphy <murphyp@linux.ibm.com> Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com> Fixes: e905212627350d54b58426214b5a54ddc852b0c9
2019-09-19 Paul A. Clarke <pc@us.ibm.com>
* sysdeps/powerpc/fpu/fenv_libc.h (fegetenv_and_set_rn): New.
(__fe_mffscrn): New.
* sysdeps/powerpc/fpu/fenv_private.h (libc_feholdsetround_ppc_ctx):
Do not clear enable bits, remove obsolete code, use
fegetenv_and_set_rn.
(libc_feresetround_ppc): Remove obsolete code, use
fegetenv_and_set_rn.
Stefan Liebler [Thu, 19 Sep 2019 10:26:18 +0000 (12:26 +0200)]
Fix building support_ptrace.c on i686-gnu.
On i686-gnu the build is broken:
In file included from support_ptrace.c:22:
../include/sys/prctl.h:2:15: fatal error: sys/prctl.h: No such file or directory
#include_next <sys/prctl.h>
This patch just removes the unused prctl.h inclusion.
ChangeLog:
* support/support_ptrace.c: Remove inclusion of sys/prctl.h.
Joseph Myers [Wed, 18 Sep 2019 13:22:24 +0000 (13:22 +0000)]
Fix RISC-V vfork build with Linux 5.3 kernel headers.
Building glibc for RISC-V with Linux 5.3 kernel headers fails because
<linux/sched.h>, included in vfork.S for CLONE_* constants, contains a
structure definition not safe for inclusion in assembly code.
All other architectures already avoid use of that header in vfork.S,
either defining the CLONE_* constants locally or embedding the
required values directly in the relevant instruction, where they
implement vfork using the clone syscall (see the implementations for
aarch64, ia64, mips and nios2). This patch makes the RISC-V version
define the constants locally like the other architectures.
Tested build for all three RISC-V configurations in
build-many-glibcs.py with Linux 5.3 headers.
* sysdeps/unix/sysv/linux/riscv/vfork.S: Do not include
<linux/sched.h>.
(CLONE_VM): New macro.
(CLONE_VFORK): Likewise.
Stefan Liebler [Wed, 18 Sep 2019 10:40:00 +0000 (12:40 +0200)]
Add UNSUPPORTED check in elf/tst-pldd.
The testcase forks a child process and runs pldd with PID of
this child. On systems where /proc/sys/kernel/yama/ptrace_scope
differs from zero, pldd will fail with
/usr/bin/pldd: cannot attach to process 3: Operation not permitted
This patch checks if ptrace_scope exists, is zero "classic ptrace permissions"
or one "restricted ptrace". If ptrace_scope exists and has a higher
restriction, then the test is marked as UNSUPPORTED.
The case "restricted ptrace" is handled by rearranging the processes involved
during the test. Now we have the following process tree:
-parent: do_test (performs output checks)
--subprocess 1: pldd_process (becomes pldd via execve)
---subprocess 2: target_process (ptraced via pldd)
There is no need to sparc64 provide an arch-specific implementation to
route to POSIX one (which uses gettimeofday). Linux one already handles
the case for architecture that does not have __NR_time.
No semantic changes, checked against a build for sparc64-linux-gnu.
This patch simplifies the powerpc internal macros for vDSO calls
by:
- Removing INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK, used solely on
get_timebase_freq.
- Adjust INTERNAL_VSYSCALL_CALL_TYPE powerpc32 to follow powerpc64
argument ordering.
- Use HAVE_*_VSYSCALL instead of explicit strings.
- Make powerpc libc-vdso.h include generic implementation.
No semantic change expected, checked on powerpc-linux-gnu-power4,
powerpc64-linux-gnu, and powerpc64le-linux-gnu.
* sysdeps/unix/sysv/linux/libc-vdso.h (VDSO_IFUNC_RET): Define if not
defined.
* sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
(__get_timebase_freq): Remove use of
INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK.
(get_timebase_freq_fallback): New symbol.
* sysdeps/unix/sysv/linux/powerpc/gettimeofday.c (time): Use
HAVE_GETTIMEOFDAY_VSYSCALL.
* sysdeps/unix/sysv/linux/powerpc/time.c (gettimeofday): Use
HAVE_TIME_VSYSCALL.
* sysdeps/unix/sysv/linux/powerpc/libc-vdso.h: Include generic
implementation.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
(INTERNAL_VSYSCALL_CALL_TYPE): Make calling convention similar to
powerpc64.
(INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK): Remove macro.
* .../sysv/linux/powerpc/powerpc64/sysdep.h
(INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK): Likewise.
* sysdeps/unix/sysv/linux/powerpc/sysdep.h
(HAVE_GETTIMEOFDAY_VSYSCALL): Define.
Linux vDSO initialization code the internal function pointers require a
lot of duplicated boilerplate over different architectures. This patch
aims to simplify not only the code but the required definition to enable
a vDSO symbol.
The changes are:
1. Consolidate all init-first.c on only one implementation and enable
the symbol based on HAVE_*_VSYSCALL existence.
2. Set the HAVE_*_VSYSCALL to the architecture expected names string.
3. Add a new internal implementation, get_vdso_mangle_symbol, which
returns a mangled function pointer.
Currently the clock_gettime, clock_getres, gettimeofday, getcpu, and time
are handled in an arch-independent way, powerpc still uses some
arch-specific vDSO symbol handled in a specific init-first implementation.
Checked on aarch64-linux-gnu, arm-linux-gnueabihf, i386-linux-gnu,
mips64-linux-gnu, powerpc64le-linux-gnu, s390x-linux-gnu,
sparc64-linux-gnu, and x86_64-linux-gnu.
This patch removes the PREPARE_VERSION and PREPARE_VERSION_KNOW macro
and uses a static inline function instead, get_vdso_symbol. Each
architecture that supports vDSO must define the Linux version and its
hash for symbol resolution (VDSO_NAME and VDSO_HASH macro respectively).
It also organizes the HAVE_*_VSYSCALL for mips, powerpc, and s390 to
define them on a common header.
The idea is to require less code to configure and enable vDSO support
for newer ports. No semantic changes are expected.
Checked with a build against all affected architectures.
Fix small error in HP_TIMING_PRINT trailing null char setting
Fix a small error in the HP_TIMING_PRINT trailing zero setting; the '\0'
should be set at MIN(Len,string length), instead of always at the 'Len'
position.
* sysdeps/generic/hp-timing-common.h (HP_TIMING_PRINT): Correct
position of string null termination.
alpha: force old OSF1 syscalls for getegid, geteuid and getppid [BZ #24986]
On alpha, Linux kernel 5.1 added the standard getegid, geteuid and
getppid syscalls (commit ecf7e0a4ad15287). Up to now alpha was using
the corresponding OSF1 syscalls through:
- sysdeps/unix/alpha/getegid.S
- sysdeps/unix/alpha/geteuid.S
- sysdeps/unix/alpha/getppid.S
When building against kernel headers >= 5.1, the glibc now use the new
syscalls through sysdeps/unix/sysv/linux/syscalls.list. When it is then
used with an older kernel, the corresponding 3 functions fail.
A quick fix is to move the OSF1 wrappers under the
sysdeps/unix/sysv/linux/alpha directory so they override the standard
linux ones. A better fix would be to try the new syscalls and fallback
to the old OSF1 in case the new ones fail. This can be implemented in
a later commit.
Changelog:
[BZ #24986]
* sysdeps/unix/alpha/getegid.S: Move to ...
* sysdeps/unix/sysv/linux/alpha/getegid.S: ... here.
* sysdeps/unix/alpha/geteuid.S: Move to ...
* sysdeps/unix/sysv/linux/alpha/geteuid.S: ... here.
* sysdeps/unix/alpha/getppid.S: Move to ...
* sysdeps/unix/sysv/linux/alpha/getppid.S: ... here
Paul Eggert [Mon, 9 Sep 2019 21:08:46 +0000 (14:08 -0700)]
Regenerate charmap-kw.h, locfile-kw.h
This propagates the recent http->https URL changes.
Since I used gperf 3.1 to regenerate, this is also a minor
internal-to-localedef API change.
URL problem reported by Joseph Myers in:
https://www.sourceware.org/ml/libc-alpha/2019-09/msg00143.html
* locale/programs/charmap-kw.h, locale/programs/locfile-kw.h:
Regenerate with gperf 3.1.
* locale/programs/linereader.h (kw_hash_fct_t):
* locale/programs/repertoire.c (repertoiremap_hash):
2nd arg is now size_t not unsigned, for compatibility with gperf 3.1.
Paul Eggert [Sat, 7 Sep 2019 05:40:42 +0000 (22:40 -0700)]
Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:
and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:
chmod a+x sysdeps/unix/sysv/linux/riscv/configure
# Omit irrelevant whitespace and comment-only changes,
# perhaps from a slightly-different Autoconf version.
git checkout -f \
sysdeps/csky/configure \
sysdeps/hppa/configure \
sysdeps/riscv/configure \
sysdeps/unix/sysv/linux/csky/configure
# Omit changes that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
git checkout -f \
sysdeps/powerpc/powerpc64/ppc-mcount.S \
sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
# Omit change that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
When the const attribute of totalorder* functions was replaced with the
pure attribute, by commit ID ab41100bab12, it did not use the
__attribute_pure__ macro, but the __attribute__ ((__pure__)) statement.
All other uses of the pure attribute in glibc use the macro.
Make totalorder and totalordermag functions take pointer arguments.
the test case math/test-totalorderl-ldbl-128ibm fails on every input
pair, when compiled with -O2, which is the case for glibc test suite.
Debugging showed that the test case is passing arguments incorrectly to
totalorderl. This can also be inferred by the fact that compiling the
test case with -O0 hides the bug.
The documentation for the const attribute in GCC manual reads:
Note that a function that has pointer arguments and examines the data
pointed to must not be declared const if the pointed-to data might
change between successive invocations of the function. In general,
since a function cannot distinguish data that might change from data
that cannot, const functions should never take pointer or, in C++,
reference arguments. Likewise, a function that calls a non-const
function usually must not be const itself.
Since the pointed-to data is likely to be changed by user code between
invocations of totalorder*, this patch removes the const attribute from
the declarations of all totalorder functions, replacing it with the pure
attribute, as suggested in the manual:
The pure attribute imposes similar but looser restrictions on a
function’s definition than the const attribute: pure allows the
function to read any non-volatile memory, even if it changes in
between successive invocations of the function.
Lukasz Majewski [Wed, 28 Aug 2019 18:27:03 +0000 (14:27 -0400)]
y2038: Introduce the __ASSUME_TIME64_SYSCALLS define
Add a macro to linux/kernel-features.h, __ASSUME_TIME64_SYSCALLS, to
indicate whether the kernel can be assumed to provide a set of system
calls that process 64-bit time_t.
__ASSUME_TIME64_SYSCALLS does not indicate whether time_t is actually
64 bits (that's __TIMEBITS) and also does not indicate whether the
64-bit time_t system calls have "time64" suffixes on their names.
Code that uses __ASSUME_TIME64_SYSCALLS will be added in subsequent
patches.
* sysdeps/unix/sysv/linux/kernel-features.h
(__ASSUME_TIME64_SYSCALLS): New macro.
Reviewed-by: Alistair Francis <alistair23@gmail.com> Reviewed-by: Joseph Myers <joseph@codesourcery.com> Reviewed-by: Zack Weinberg <zackw@panix.com>
Finish move of clock_* functions to libc. [BZ #24959]
In glibc 2.17, the functions clock_getcpuclockid, clock_getres,
clock_gettime, clock_nanosleep, and clock_settime were moved from
librt.so to libc.so, leaving compatibility stubs behind. Now that the
dynamic linker no longer insists on finding versioned symbols in the
same library that originally defined them, we do not need the stubs
anymore, and this means we don't need GLIBC_PRIVATE __-prefix aliases
for most of the functions anymore either. (clock_gettime still needs
one.) For ports added before 2.17, libc.so needs to provide two
symbol versions for each, the default at GLIBC_2.17 plus a compat
version matching what librt had.
While I'm at it, move the clock_*.c files and their tests from rt/ to
time/.
localedef: Use initializer for flexible array member [BZ #24950]
struct charseq used a zero-length array instead of a flexible array
member. This required a strange construct to initialize struct
charseq objects, and GCC 10 warns about that:
cc1: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
In file included from programs/repertoire.h:24,
from programs/localedef.h:32,
from programs/ld-ctype.c:35:
programs/charmap.h:63:17: note: destination object declared here
63 | unsigned char bytes[0];
| ^~~~~
cc1: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
programs/charmap.h:63:17: note: destination object declared here
cc1: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
programs/charmap.h:63:17: note: destination object declared here
cc1: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
programs/charmap.h:63:17: note: destination object declared here
The change makes the object physically const, but it is not expected
to be modified.
Ian Kent [Mon, 2 Sep 2019 11:26:14 +0000 (13:26 +0200)]
Use autofs "ignore" mount hint in getmntent_r/getmntent
Historically autofs mounts were not included in mount table
listings. This is the case in other SysV autofs implementations
and was also the case with Linux autofs.
But now that /etc/mtab is a symlink to the proc filesystem
mount table the autofs mount entries appear in the mount table
on Linux.
Prior to the symlinking of /etc/mtab mount table it was
sufficient to call mount(2) and simply not update /etc/mtab
to exclude autofs mounts from mount listings.
Also, with the symlinking of /etc/mtab we have seen a shift in
usage toward using the proc mount tables directly.
But the autofs mount entries need to be retained when coming
from the proc file system for applications that need them
(largely autofs file system users themselves) so filtering out
these entries within the kernel itself can't be done. So it
needs be done in user space.
There are three reasons to omit the autofs mount entries.
One is that certain types of auto-mounts have an autofs mount
for every entry in their autofs mount map and these maps can
be quite large. This leads to mount table listings containing
a lot of unnecessary entries.
Also, this change in behaviour between autofs implementations
can cause problems for applications that use getmntent(3) in
other OS implementations as well as Linux.
Lastly, there's very little that user space can do with autofs
mount entries since this must be left to the autofs mount owner,
typically the automount daemon. But it can also lead to attempts
to access automount managed paths resulting mounts being triggered
when they aren't needed or mounts staying mounted for much longer
thay they need be. While the point of this change ins't to help
with these problems (and it can be quite a problem) it may be
a welcome side effect.
So the Linux autofs file system has been modified to accept a
pseudo mount option of "ignore" (as is used in other OS
implementations) so that user space can use this as a hint to
skip autofs entries on reading the mount table.
The Linux autofs automount daemon used getmntent(3) itself and
has been modified to use the proc file system directly so that
it can "ignore" mount option.
The use of this mount option is opt-in and a configuration
option has been added which defaults to not use this option
so if there are applications that need these entries, other
than autofs itself, they can be retained. Also, since this
filtering is based on an added mount option earlier versions
of Linux autofs iand other autofs file system users will not
use the option and so won't be affected by the change.
Samuel Thibault [Thu, 29 Aug 2019 23:48:38 +0000 (01:48 +0200)]
hurd: Fix SS_ONSTACK support
* sysdeps/mach/hurd/i386/sigreturn.c (__sigreturn2): New function,
unlocks SS and returns to the saved PC.
(__sigreturn): Do not unlock SS, and "return" into __sigreturn2 on the
thread stack instead of the saved PC.
Samuel Thibault [Thu, 29 Aug 2019 23:20:23 +0000 (01:20 +0200)]
hurd: Fix poll and select POSIX compliancy details about errors
This fixes the following:
- On error, poll must not return without polling, including EBADF, and instead
report POLLHUP/POLLERR/POLLNVAL
- Select must report EBADF if some set contains an invalid FD.
The idea is to move error management to after all select calls, in the
poll/select final treatment. The error is instead recorded in a new `error'
field, and a new SELECT_ERROR bit set.
Thanks Svante Signell for the initial version of the patch.
* hurd/hurdselect.c (SELECT_ERROR): New macro.
(_hurd_select):
- Add `error' field to `d' structures array.
- If a poll descriptor is bogus, set EBADF, but continue with a zero
timeout.
- Go through the whole fd_set, not only until _hurd_dtablesize. Return
EBADF there is any bit set above _hurd_dtablesize.
- Do not request io_select on bogus descriptors (SELECT_ERROR).
- On io_select request error, record the error.
- On io_select bogus reply, use EIO error code.
- On io_select bogus or error reply, record the error.
- Do not destroy reply port for bogus FDs.
- On error, make poll set POLLHUP in the EPIPE case, POLLNVAL in the
EBADF case, or else POLLERR.
- On error, make select simulated readiness.
Richard Braun [Thu, 29 Aug 2019 23:16:37 +0000 (01:16 +0200)]
hurd: Fix timeout handling in _hurd_select
Rely on servers to implement timeouts, so that very short values (including
0) don't make mach_msg return before valid replies can be received. The
purpose of this scheme is to guarantee a full client-server round-trip,
whatever the timeout value.
This change depends on the new io_select_timeout RPC being implemented by
servers.
* hurd/Makefile (user-interfaces): Add io_reply and io_request.
* hurd/hurdselect.c: Include <sys/time.h>, <hurd/io_request.h> and
<limits.h>.
(_hurd_select): Replace the call to __io_select with either
__io_select_request or __io_select_timeout_request, depending on the
timeout. Count the number of ready descriptors (replies for which at
least one type bit is set). Implement the timeout locally when there is
no file descriptor.
Samuel Thibault [Thu, 29 Aug 2019 23:08:09 +0000 (01:08 +0200)]
hurd getcwd: Allow unknown root directory
To be efficient, the remap translator simply returns ports from the underlying
filesystem, and thus the root directory found through browsing '..' is the
underlying root, not the remap root. This should not be a reason for getcwd to
fail.
* sysdeps/mach/hurd/getcwd.c (_hurd_canonicalize_directory_name_internal): Do
not remove the heading slash if we got an unknown root directory.
(__getcwd): Do not fail with EGRATUITOUS if we got an unknown root directory.
Samuel Thibault [Thu, 29 Aug 2019 23:04:17 +0000 (01:04 +0200)]
hurd: Fix implementation of setitimer.
The preemptor sigcode doesn't match since the POSIX sigcode SI_TIMER is
used when SIGALRM is sent. In addition, The inline version of
hurd_preempt_signals doesn't update _hurdsig_preempted_set. For these
reasons, the preemptor would be skipped by post_signal.
Richard Braun [Thu, 29 Aug 2019 22:58:14 +0000 (00:58 +0200)]
hurd: Fix _hurd_select for single fd sets
The function attempts to optimize this case by performing one IPC system
call with the timeout included among the parameters, but in the absence
of a reply, it will call mach_msg again with the same timeout later,
effectively doubling the total timeout of the select/poll call.
Remove this optimization for the time being.
* hurd/hurdselect.c (_hurd_select): Always call __io_select with no
timeout.
This patch is a reimplementation of [1], which was submitted back in
2015. Copyright issue has been sorted [2] last year. It proposed a new
section (.gnu.xhash) and related dynamic tag (GT_GNU_XHASH). The new
section would be virtually identical to the existing .gnu.hash except
for the translation table (xlat) which would contain correct MIPS
.dynsym indexes corresponding to the hashvals in chains. This is because
MIPS ABI imposes a different ordering of the dynsyms than the one
expected by the .gnu.hash section. Another addition would be a leading
word at the beggining of the section, which would contain the number of
entries in the translation table.
In this patch, the new section name and dynamic tag are changed to
reflect the fact that the section should be treated as MIPS specific
(.MIPS.xhash and DT_MIPS_XHASH).
This patch addresses the alignment issue reported in [3] which is caused
by the leading word of the .MIPS.xhash section. Leading word is now
removed in the corresponding binutils patch, and the number of entries
in the translation table is computed using DT_MIPS_SYMTABNO dynamic tag.
Since the MIPS specific dl-lookup.c file was removed following the
initial patch submission, I opted for the definition of three new macros
in the generic ldsodefs.h. ELF_MACHINE_GNU_HASH_ADDRIDX defines the
index of the dynamic tag in the l_info array. ELF_MACHINE_HASH_SYMIDX is
used to calculate the index of a symbol in GNU hash. On MIPS, it is
defined to look up the symbol index in the translation table.
ELF_MACHINE_XHASH_SETUP is defined for MIPS only. It initializes the
.MIPS.xhash pointer in the link_map_machine struct.
The other major change is bumping the highest EI_ABIVERSION value for
MIPS to suggest that the dynamic linker now supports GNU hash.
The patch was tested by running the glibc testsuite for the three MIPS
ABIs (o32, n32 and n64) and for x86_64-linux-gnu.
* elf/dl-addr.c (determine_info): Calculate the symbol index
using the newly defined ELF_MACHINE_HASH_SYMIDX macro.
* elf/dl-lookup.c (do_lookup_x): Ditto.
(_dl_setup_hash): Initialize MIPS xhash translation table.
* elf/elf.h (SHT_MIPS_XHASH): New define.
(DT_MIPS_XHASH): New define.
* sysdeps/generic/ldsodefs.h (ELF_MACHINE_GNU_HASH_ADDRIDX): New
define.
(ELF_MACHINE_HASH_SYMIDX): Ditto.
(ELF_MACHINE_XHASH_SETUP): Ditto.
* sysdeps/mips/ldsodefs.h (ELF_MACHINE_GNU_HASH_ADDRIDX): New
define.
(ELF_MACHINE_HASH_SYMIDX): Ditto.
(ELF_MACHINE_XHASH_SETUP): Ditto.
* sysdeps/mips/linkmap.h (struct link_map_machine): New member.
* sysdeps/unix/sysv/linux/mips/ldsodefs.h: Increment valid ABI
version.
* sysdeps/unix/sysv/linux/mips/libc-abis: New ABI version.
The fix for BZ#18231 requires new symbols only for sh4eb. This patch
adds the required folder and files for both BE and LE abilist. No
semantic changes are expected.
Checked with check-abi for sh4eb-linux-gnu and sh4-linux-gnu.
* sysdeps/sh/preconfigure.ac: New file.
* sysdeps/sh/preconfigure: Regenerate.
* sysdeps/sh/be/sh3/Implies: New file.
* sysdeps/sh/be/sh4/Implies: Likewise.
* sysdeps/sh/le/sh3/Implies: Likewise.
* sysdeps/sh/le/sh4/Implies: Likewise.
* sysdeps/unix/sysv/linux/sh/le/sh3/Implies: Likewise.
* sysdeps/unix/sysv/linux/sh/le/sh4/Implies: Likewise.
* sysdeps/unix/sysv/linux/sh/*.abilist: Move to
sysdeps/unix/sysv/linux/sh/le/*.abilist.
* sysdeps/unix/sysv/linux/sh/be/*.abilist: New files.
The fix for BZ#18231 requires new symbols only for microblaze. This patch
adds the required folder and files for both BE and LE abilist. No semantic
changes are expected.
Checked with check-abi for microblaze-linux-gnueabihf and
microblazeel-linux-gnueabihf.
* sysdeps/microblaze/preconfigure.ac: New file.
* sysdeps/microblaze/preconfigure: Regenerate.
* sysdeps/microblaze/be/implies: New file.
* sysdeps/microblaze/le/implies: Likewise.
* sysdeps/unix/sysv/linux/microblaze/be/implies: Likewise.
* sysdeps/unix/sysv/linux/microblaze/le/implies: Likewise.
* sysdeps/unix/sysv/linux/microblaze/*.abilist. Move to
sysdeps/unix/sysv/linux/microblaze/be/*.abilist.
* sysdeps/unix/sysv/linux/microblaze/le/*.abilist: New files.
The fix for BZ#18231 requires new symbols only for armeb. This patch
adds the required folder and files for both BE and LE abilist. No
semantic changes are expected.
Checked with check-abi for arm-linux-gnueabihf and armeb-linux-gnueabihf.
* sysdeps/arm/preconfigure.ac: Set machine based on endianness.
* sysdeps/arm/preconfigure: Regenerate.
* sysdeps/arm/be/Implies: New file.
* sysdeps/arm/be/armv6/Implies: Likewise.
* sysdeps/arm/be/armv6t2/Implies: Likewise.
* sysdeps/arm/be/armv7/Implies: Likewise.
* sysdeps/arm/le/Implies: Likewise.
* sysdeps/unix/sysv/linux/arm/be/Implies: Likewise.
* sysdeps/unix/sysv/linux/arm/le/Implies: Likewise.
* sysdeps/unix/sysv/linux/arm/*.abilist: Move to
sysdeps/unix/sysv/linux/arm/le/*.abilist.
* sysdeps/unix/sysv/linux/arm/be/l*.abilist: New files.
Paul Eggert [Thu, 29 Aug 2019 09:34:13 +0000 (02:34 -0700)]
Fix posix/tst-regex by using UTF-8 and own test input
Problem reported by Stefan Liebler in:
https://sourceware.org/ml/libc-alpha/2019-08/msg00658.html
* posix/tst-regex.c: Convert this file from Latin-1 to UTF-8.
(do_test, test_expr): Adjust to the fact that this source file,
and the test data in ChangeLog.8, is now UTF-8 instead of Latin-1.
* posix/tst-regex.input: Copy from ChangeLog.old/ChangeLog.8,
so that it is now UTF-8.
fegetenv_status() wants to use the lighter weight instruction 'mffsl'
for reading the Floating-Point Status and Control Register (FPSCR).
It currently will use it directly if compiled '-mcpu=power9', and will
perform a runtime check (cpu_supports("arch_3_00")) otherwise.
Nicely, it turns out that the 'mffsl' instruction will decode to
'mffs' on architectures older than "arch_3_00" because the additional
bits set for 'mffsl' are "don't care" for 'mffs'. 'mffs' is a superset
of 'mffsl'.
Paul A. Clarke [Tue, 6 Aug 2019 04:13:45 +0000 (00:13 -0400)]
[powerpc] fesetenv: optimize FPSCR access
fesetenv() reads the current value of the Floating-Point Status and Control
Register (FPSCR) to determine the difference between the current state of
exception enables and the newly requested state. All of these bits are also
returned by the lighter weight 'mffsl' instruction used by fegetenv_status().
Use that instead.
Also, remove a local macro _FPU_MASK_ALL in favor of a common macro,
FPU_ENABLES_MASK from fenv_libc.h.
Finally, use a local variable ('new') in favor of a pointer dereference
('*envp').
Paul A. Clarke [Sat, 3 Aug 2019 02:47:57 +0000 (22:47 -0400)]
[powerpc] SET_RESTORE_ROUND improvements
SET_RESTORE_ROUND uses libc_feholdsetround_ppc_ctx and
libc_feresetround_ppc_ctx to bracket a block of code where the floating point
rounding mode must be set to a certain value.
For the *prologue*, libc_feholdsetround_ppc_ctx is used and performs:
1. Read/save FPSCR.
2. Create new value for FPSCR with new rounding mode and enables cleared.
3. If new value is different than current value,
a. If transitioning from a state where some exceptions enabled,
enter "ignore exceptions / non-stop" mode.
b. Write new value to FPSCR.
c. Put a mark on the wall indicating the FPSCR was changed.
(1) uses the 'mffs' instruction. On POWER9, the lighter weight 'mffsl'
instruction can be used, but it doesn't return all of the bits in the FPSCR.
fegetenv_status uses 'mffsl' on POWER9, 'mffs' otherwise, and can thus be
used instead of fegetenv_register.
(3b) uses 'mtfsf 0b11111111' to write the entire FPSCR, so it must
instead use 'mtfsf 0b00000011' to write just the enables and the mode,
because some of the rest of the bits are not valid if 'mffsl' was used.
fesetenv_mode uses 'mtfsf 0b00000011' on POWER9, 'mtfsf 0b11111111'
otherwise.
For the *epilogue*, libc_feresetround_ppc_ctx checks the mark on the wall, then
calls libc_feresetround_ppc, which just calls __libc_femergeenv_ppc with
parameters such that it performs:
1. Retreive saved value of FPSCR, saved in prologue above.
2. Read FPSCR.
3. Create new value of FPSCR where:
- Summary bits and exception indicators = current OR saved.
- Rounding mode and enables = saved.
- Status bits = current.
4. If transitioning from some exceptions enabled to none,
enter "ignore exceptions / non-stop" mode.
5. If transitioning from no exceptions enabled to some,
enter "catch exceptions" mode.
6. Write new value to FPSCR.
The summary bits are hardwired to the exception indicators, so there is no
need to restore any saved summary bits.
The exception indicator bits, which are sticky and remain set unless
explicitly cleared, would only need to be restored if the code block
might explicitly clear any of them. This is certainly not expected.
So, the only bits that need to be restored are the enables and the mode.
If it is the case that only those bits are to be restored, there is no need to
read the FPSCR. Steps (2) and (3) are unnecessary, and step (6) only needs to
write the bits being restored.
We know we are transitioning out of "ignore exceptions" mode, so step (4) is
unnecessary, and in step (6), we only need to check the state we are
entering.
Since fe{en,dis}ableexcept() and fesetmode() read-modify-write just the
"mode" (exception enable and rounding mode) bits of the Floating Point Status
Control Register (FPSCR), the lighter weight 'mffsl' instruction can be used
to read the FPSCR (enables and rounding mode), and 'mtfsf 0b00000011' can be
used to write just those bits back to the FPSCR. The net is better performance.
In addition, fe{en,dis}ableexcept() read the FPSCR again after writing it, or
they determine that it doesn't need to be written because it is not changing.
In either case, the local variable holds the current values of the enable
bits in the FPSCR. This local variable can be used instead of again reading
the FPSCR.
Also, that value of the FPSCR which is read the second time is validated
against the requested enables. Since the write can't fail, this validation
step is unnecessary, and can be removed. Instead, the exceptions to be
enabled (or disabled) are transformed into available bits in the FPSCR,
then validated after being transformed back, to ensure that all requested
bits are actually being set. For example, FE_INVALID_SQRT can be
requested, but cannot actually be set. This bit is not mapped during the
transformations, so a test for that bit being set before and after
transformations will show the bit would not be set, and the function will
return -1 for failure.
Finally, convert the local macros in fesetmode.c to more generally useful
macros in fenv_libc.h.
Paul A. Clarke [Sat, 13 Jul 2019 01:13:58 +0000 (20:13 -0500)]
[powerpc] fe{en,dis}ableexcept optimize bit translations
The exceptions passed to fe{en,dis}ableexcept() are defined in the ABI
as a bitmask, a combination of FE_INVALID, FE_OVERFLOW, etc.
Within the functions, these bits must be translated to/from the corresponding
enable bits in the Floating Point Status Control Register (FPSCR).
This translation is currently done bit-by-bit. The compiler generates
a series of conditional bit operations. Nicely, the "FE" exception
bits are all a uniform offset from the FPSCR enable bits, so the bit-by-bit
operation can instead be performed by a shift with appropriate masking.