Rich Felker bbe6c77857 sh: make sigcontext definition consistent across fpu/nofpu models ... Up until now, the SH version of the sigcontext structure, and thus mcontext_t/ucontext_t, varied depending on the cpu model the kernel was built to run on. SH-4 (including SH-4A) and SH-2A used the form with space for FPU registers, and everything else used a form that omitted them. From a userspace perspective, however, the structure layout must be fixed for a given ABI. Traditionally glibc and uClibc used the form with space for FPU registers only when __SH4__ (which implies FPU; __SH4_NOFPU__ is the predefined macro for SH-4 but with no-FPU ABI) was defined. As a result: - SH-4 no-FPU programs never matched kernel sigcontext. - SH-3 programs did not match kernel sigcontext if run on SH-4, despite an apparent intent that they be compatible. - SH-2 and SH-2A programs (using uClibc) did not match kernel sigcontext if run on SH-2A. The mismatch might seem inconsequential because it occurs at the end of the sigcontext structure, but sigcontext is embedded as uc_mcontext in ucontext_t, where it is followed by uc_sigmask, an important member for signal handlers to have access to. In particular, access to uc_sigmask is necessary for a correct implementation of thread cancellation. It would be possible to retain support for both sigcontext ABIs via a personality mechanism, but since many configurations were already broken and nobody noticed, and since there are very few if any users of legacy no-FPU models anymore, I have opted to just remove the variation and always include space for the FPU registers in sigcontext. This was proposed and discussed on a thread "SH sigcontext ABI is broken" cross-posted to linux-sh, libc-alpha, and musl libc lists in June 2015, and no objections were raised. Signed-off-by: Rich Felker <dalias@libc.org>		2016-07-31 03:33:32 +00:00
..
auxvec.h
byteorder.h
cachectl.h
cpu-features.h
hw_breakpoint.h	UAPI: Make arch/sh/include/uapi/asm/hw_breakpoint.h non-empty	2012-10-17 12:32:35 +01:00
ioctls.h	sh/uapi: Add definition of TIOC[SG]RS485	2014-09-09 22:36:40 -07:00
Kbuild
posix_types_32.h
posix_types_64.h
posix_types.h
ptrace_32.h
ptrace_64.h
ptrace.h
setup.h
sigcontext.h	sh: make sigcontext definition consistent across fpu/nofpu models	2016-07-31 03:33:32 +00:00
signal.h	sh: switch to generic old sigaction()	2013-02-03 18:16:16 -05:00
sockios.h
stat.h
swab.h
types.h
unistd_32.h	sh: wire up finit_module syscall.	2013-01-14 17:59:03 +09:00
unistd_64.h	sh64: fix __NR_fgetxattr	2015-12-12 10:15:34 -08:00
unistd.h