On most architectures the kernel subtracts a random offset to the stack
pointer in create_elf_tables by calling arch_align_stack before writing
the auxval table and so on. On all but x86 this doesn't cause a problem
because the random offset is less than a page, but on x86 it's up to two
pages. This means that our old technique of rounding the stack pointer
doesn't work. (Our old implementation of that technique was wrong too.)
It's also incorrect to assume that the main thread's stack base and size
are constant. Likewise to assume that the main thread has a guard page.
The main thread is not like other threads.
This patch switches to reading /proc/self/maps (and checking RLIMIT_STACK)
whenever we're asked.
Bug: 17111575
Signed-off-by: Fengwei Yin <fengwei.yin@intel.com>
Change-Id: I1d4dbffe7bc7bda1d353c3a295dbf68d29f63158
The old definition only worked for functions that didn't use numbered
local labels. Upstream uses '666' not only as some kind of BSD in-joke,
but also because there's little likelihood of any function having
labels that high.
There's a wider question about whether we actually want to go via the
PLT at all in this code, but that's a question for another day.
(cherry-pick of 72d7e667c7e926cb120c4edb53cbf74c652ab915.)
Bug: 16906712
Change-Id: I3cd8ecc448b33f942bb6e783931808ef39091489
Clean up the x86/x86_64 assembler. The motivator (other than reducing
confusion) was that asm.h incorrectly checked PIC rather than __PIC__.
Bug: 16823325
Change-Id: Iaa9d45009e93a4b31b719021c93ac221e336479b
Also fix a few formatting issues in copyright headers that were confusing
the script (though obviously it would be better if the script were smarter).
Change-Id: I7f561bef4f84fdcbd84f375ee226bd65db0e507b
In practice, with this implementation we never need to make a system call.
We get the main thread's tid (which is the same as our pid) back from
the set_tid_address system call we have to make during initialization.
A new pthread will have the same pid as its parent, and a fork child's
main (and only) thread will have a pid equal to its tid, which we get for
free from the kernel before clone returns.
The only time we'd actually have to make a getpid system call now is if
we take a signal during fork and the signal handler calls getpid. (That,
or we call getpid in the dynamic linker while it's still dealing with its
own relocations and hasn't even set up the main thread yet.)
Bug: 15387103
Change-Id: I6d4718ed0a5c912fc75b5f738c49a023dbed5189
The C library didn't export the 'index' symbol, but its C++ name-mangling
instead, which broke the ABI and prevented some applications from loading
properly.
The main reason was that the implementation under bionic/index.cpp relied
on the declaration to specify that the function has C linkage.
However, the declaration for index() was removed from both <string.h>
and <strings.h> in a recent patch, which made the compiler think it was
ok to compile the function with C++ linkage instead!
This patch does the following:
- Move index() definition to bionic/ndk_cruft.cpp and ensure it uses
C linkage.
Note that this removes index() from the 64-bit library entirely, this
is intentional and will break source compatibility. Simply replacing
an index() call with the equivalent strchr() should be enough to fix
this in third-party code.
- Remove bionic/index.cpp from the tree and build files.
- Remove x86 assembly implementation from arch-x86/ to avoid conflict
with the one in ndk_cruft.cpp
BUG=15606653
Change-Id: I816b589f69c8f8a6511f6be6195d20cf1c4e8123
These were both removed from POSIX 2004, and we don't define an
implementation for getw(3). Keep the definition of put(3) on LP32 for
binary compatibility.
Bug: 13935372
Change-Id: Iba384b45093ac6d2d7c2d81f7980cd7701dd6f56
vfork() was removed from POSIX 2008, so this replaces its implementation
with a call to fork().
Bug: 13935372
Change-Id: I6d99ac9e52a2efc5ee9bda1cab908774b830cedc
__set_errno returns -1 exactly so that callers don't need to bother.
The other architectures were already taking advantage of this, but
no one had ever fixed x86 and x86_64.
Change-Id: Ie131494be664f6c4a1bbf8c61bbbed58eac56122
x86-64 needs these CFI directives to stop unwinding here.
I've also cleaned up the assembler a little, and made x86 and x86-64
a little more alike.
Bug: 15195760
Change-Id: I40f92c007843c29c933bb6876fe2b4611e1b946b
Introduce a test for memmove that catches a fault.
Fix both 32- and 64-bit versions of slm-tuned memmove.
Change-Id: Ib416def2610a0972e32c3b9b6055b54967643dc3
Signed-off-by: Varvara Rainchik <varvara.rainchik@intel.com>
System calls can be pretty slow. This is mako, which has one of our
lowest latencies:
iterations ns/op
BM_unistd_getpid 10000000 209
BM_unistd_gettid 200000000 8
Bug: 15297299 (kernel panic from too many gettid calls)
Bug: 15315766 (excessive gettid overhead in liblogd)
Change-Id: I49656c0fc5b5d092390264a59e4f2c0d8a8b1aeb
The syscall generation always used 4 bytes for each push cfi directive.
However, the first push should always use an offset of 8 bytes, each
subsequent push after that is only 4 bytes though.
Change-Id: Ibaabd107f399ef67010b9a08213783957c2f74a9
The problem with the original patch was that using syscall(3) means that
errno can be set, but pthread_create(3) was abusing the TLS errno slot as
a pthread_mutex_t for the thread startup handshake.
There was also a mistake in the check for syscall failures --- it should
have checked against -1 instead of 0 (not just because that's the default
idiom, but also here because futex(2) can legitimately return values > 0).
This patch stops abusing the TLS errno slot and adds a pthread_mutex_t to
pthread_internal_t instead. (Note that for LP64 sizeof(pthread_mutex_t) >
sizeof(uintptr_t), so we could potentially clobber other TLS slots too.)
I've also rewritten the LP32 compatibility stubs to directly reuse the
code from the .h file.
This reverts commit 75c55ff84e.
Bug: 15195455
Change-Id: I6ffb13e5cf6a35d8f59f692d94192aae9ab4593d
This reverts commit ced906c849.
Causes issues on art / dalvik due to a broken return value
check and other undiagnosed issues.
bug: 15195455
Change-Id: I5d6bbb389ecefb0e33a5237421a9d56d32a9317c
Add optimized versions of bcopy and wmemmove for AArch64 based on the
memmove implementation
Change-Id: I82fbe8a7221ce224c567ffcfed7a94a53640fca8
Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>
This reverts commit 8167dd7cb9.
For some reason I thought the bcopy change was bzero. The bcopy code doesn't pass our tests, so reverting until I can figure out what's wrong.
Change-Id: Id89fe959ea5105cd58dff6bba8d91a30cc4bcb07
Add optimized versions of bcopy and wmemmove for AArch64 based on the
memmove implementation
Change-Id: Ie43d0ff4f8ec4edba5b4fb5ccacd941f81ac6557
Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>
glibc doesn't have tkill or tgkill and says "use syscall(3) instead".
I've left tgkill since it's quite widely used, but there's no reason
to have tkill as well.
Bug: 11156955
Change-Id: Ifc0af750320086f829bc9914551c172b501f3b60
Also hide part of the system properties compatibility code, since
we needed to touch that to keep it building.
I'll remove __futex_syscall4 and futex in a later patch.
Bug: 11156955
Change-Id: Ibbf42414c5bb07fb9f1c4a169922844778e4eeae
This was accidentally added at a time when you couldn't add a constant
to <syscall.h> without generating an assembly stub! (You no longer need
to add the constants at all.)
Bug: 11156955
Change-Id: I053c17879138787976c744a5ecf7d30ee51dc48f
