The IFUNC selector for gettimeofday runs before _libc_vdso_platform_setup where
__vdso_gettimeofday is set. The selector then sets __gettimeofday (the internal
version used within GLIBC) to use the system call version instead of the vDSO one.
This patch changes the check if vDSO is available to get its value directly
instead of rely on __vdso_gettimeofday.
This patch changes it by getting the vDSO value directly.
It fixes BZ#16431.
This patches fixes BZ#16430 by setting a different symbol for internal
GLIBC calls that points to ifunc resolvers. For PPC32, if the symbol
is defined as hidden (which is the case for gettimeofday and time) the
compiler will create local branches (symbol@local) and linker will not
create PLT calls (required for IFUNC). This will leads to internal symbol
calling the IFUNC resolver instead of the resolved symbol.
For PPC64 this behavior does not occur because a call to a function in
another translation unit might use a different toc pointer thus requiring
a PLT call.
This patch fixes the vDSO symbol used directed in IFUNC resolver where
they do not have an associated ODP entry leading to undefined behavior
in some cases. It adds an artificial OPD static entry to such cases
and set its TOC to non 0 to avoid triggering lazy resolutions.
Tom Gall <tom_gall@vnet.ibm.com>
* elf/rtld.c (dl_main): Initialize l_local_scope for sysinfo_map.
* sysdeps/powerpc/elf/libc-start.c: Move this...
* sysdeps/unix/sysv/linux/powerpc/libc-start.c: ...to here.
* sysdeps/powerpc/powerpc32/dl-start.S: Add _dl_main_dispatch label.
* sysdeps/powerpc/powerpc32/hp-timing.h: New file.
* sysdeps/unix/sysv/linux/powerpc/Versions: New file.
* sysdeps/unix/sysv/linux/clock_getres.c: If HAVE_CLOCK_GETRES_VSYSCALL
is not defined, redefine INTERNAL_VSYSCALL and INLINE_VSYSCALL to
INTERNAL_SYSCALL and INLINE_SYSCALL respectively. Otherwise include
<bits/libc-vdso.h>. Use INLINE_VSYSCALL and INTERNAL_SYSCALL instead
of the normal versions throughout the code.
* sysdeps/unix/sysv/linux/clock_gettime.c: Likewise if
HAVE_CLOCK_GETTIME_VSYSCALL is defined.
* sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h: New file.
* sysdeps/unix/sysv/linux/powerpc/dl-vdso.c: New file.
* sysdeps/unix/sysv/linux/powerpc/dl-vdso.h: New file.
* sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c: Use vDSO.
* sysdeps/unix/sysv/linux/powerpc/gettimeofday.c: New file.
* sysdeps/unix/sysv/linux/powerpc/Makefile: Add dl-vdso to routines.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h: Define
INLINE_VSYSCALL, INTERNAL_VSYSCALL, INTERNAL_SYSCALL_NCS,
INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK, HAVE_CLOCK_GETRES_VSYSCALL,
and HAVE_CLOCK_GETTIME_VSYSCALL.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h: Likewise.