Will Newton 37d3500738 aarch64: Re-implement setcontext without rt_sigreturn syscall ... The current implementation of setcontext uses rt_sigreturn to restore the contents of registers. This contrasts with the way most other architectures implement setcontext: powerpc64, mips, tile: Call rt_sigreturn if context was created by a call to a signal handler, otherwise restore in user code. powerpc32: Call swapcontext system call and don't call sigreturn or rt_sigreturn. x86_64, sparc, hppa, sh, ia64, m68k, s390, arm: Only support restoring "synchronous" contexts, that is contexts created by getcontext, and restoring in user code and don't call sigreturn or rt_sigreturn. alpha: Call sigreturn (but not rt_sigreturn) in all cases to do the restore. The text of the setcontext manpage suggests that the requirement to be able to restore a signal handler created context has been dropped from SUSv2: If the context was obtained by a call to a signal handler, then old standard text says that "program execution continues with the program instruction following the instruction interrupted by the signal". However, this sentence was removed in SUSv2, and the present verdict is "the result is unspecified". Implementing setcontext by calling rt_sigreturn unconditionally causes problems when used with sigaltstack as in BZ #16629. On this basis it seems that aarch64 is broken and that new ports should only support restoring contexts created with getcontext and do not need to call rt_sigreturn at all. This patch re-implements the aarch64 setcontext function to restore the context in user code in a similar manner to x86_64 and other ports. ChangeLog: 2014-04-17 Will Newton <will.newton@linaro.org> [BZ #16629] * sysdeps/unix/sysv/linux/aarch64/setcontext.S (__setcontext): Re-implement to restore registers in user code and avoid rt_sigreturn system call.		2014-04-17 11:38:50 +01:00
..
alpha	alpha: Fix __pointer_chk_guard definition for the testsuite	2014-04-16 21:35:27 -07:00
arm	Move arm from ports to libc.	2014-02-08 01:49:39 +00:00
bsd
i386
inet
mips	Move mips from ports to libc.	2014-02-10 23:30:21 +00:00
powerpc
sh
sysv/linux	aarch64: Re-implement setcontext without rt_sigreturn syscall	2014-04-17 11:38:50 +01:00
x86_64
clock_gettime.c	Use glibc_likely instead __builtin_expect.	2014-02-10 15:07:12 +01:00
clock_nanosleep.c
clock_settime.c	Use glibc_likely instead __builtin_expect.	2014-02-10 15:07:12 +01:00
confstr.h
get_child_max.c
getlogin_r.c
getlogin.c
getpagesize.c
grantpt.c	Use glibc_likely instead __builtin_expect.	2014-02-10 15:07:12 +01:00
ifreq.c
Implies
make-syscalls.sh
Makefile
s-proto-cancel.S
s-proto.S
setxid.h
sockatmark.c
stime.c
Subdirs
syscall-template.S
syscall.S
syscalls.list
sysdep.h