This patch adds support for the ELFv2 ABI feature to remove function
descriptors. See this GCC patch for in-depth discussion:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01141.html
This mostly involves two types of changes: updating assembler source
files to the new logic, and updating the dynamic loader.
After the refactoring in the previous patch, most of the assembler source
changes can be handled simply by providing ELFv2 versions of the
macros in sysdep.h. One somewhat non-obvious change is in __GI__setjmp:
this used to "fall through" to the immediately following __setjmp ENTRY
point. This is no longer safe in the ELFv2 since ENTRY defines both
a global and a local entry point, and you cannot simply fall through
to a global entry point as it requires r12 to be set up.
Also, makecontext needs to be updated to set up registers according to
the new ABI for calling into the context's start routine.
The dynamic linker changes mostly consist of removing special code
to handle function descriptors. We also need to support the new PLT
and glink format used by the the ELFv2 linker, see:
https://sourceware.org/ml/binutils/2013-10/msg00376.html
In addition, the dynamic linker now verifies that the dynamic libraries
it loads match its own ABI.
The hack in VDSO_IFUNC_RET to "synthesize" a function descriptor
for vDSO routines is also no longer necessary for ELFv2.
This is the first patch to support the new ELFv2 ABI in glibc.
As preparation, this patch simply refactors some of the powerpc64 assembler
code to move all code related to creating function descriptors (.opd section)
or using function descriptors (function pointer call) into a central place
in sysdep.h.
Note that most locations creating .opd entries were already using macros
in sysdep.h, this patch simply extends this to the remaining places.
No relevant change in generated code expected.
The context established by "makecontext" has a link register pointing
back to an error path within the makecontext routine. This is currently
covered by the CFI FDE for makecontext itself, which is simply wrong
for the stack frame *inside* the context. When trying to unwind (e.g.
doing a backtrace) in a routine inside a context created by makecontext,
this can lead to uninitialized stack slots being accessed, causing the
unwinder to crash in the worst case.
Similarly, during parts of the "setcontext" routine, when the stack
pointer has already been switched to point to the new context, the
address range is still covered by the CFI FDE for setcontext. When
trying to unwind in that situation (e.g. backtrace from an async
signal handler for profiling), it is again possible that the unwinder
crashes.
Theses are all problems in existing code, but the changes in stack
frame layout appear to make the "worst case" much more likely in
the ELFv2 ABI context. This causes regressions e.g. in the libgo
testsuite on ELFv2.
This patch fixes this by ending the makecontext/setcontext FDEs
before those problematic parts of the assembler, similar to what
is already done on other platforms. This fixes the libgo
regression on ELFv2.
http://sourceware.org/ml/libc-alpha/2013-08/msg00092.html
Use conditional form of branch and link to avoid destroying the cpu
link stack used to predict blr return addresses.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S: Use
conditional form of branch and link when obtaining pc.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S: Likewise.
This patch introduces two new convenience functions to set the default
thread attributes used for creating threads. This allows a programmer
to set the default thread attributes just once in a process and then
run pthread_create without additional attributes.
This feature is specifically for the C++ compiler to offload calling
thread_local object destructors on thread program exit, to glibc.
This is to overcome the possible complication of destructors of
thread_local objects getting called after the DSO in which they're
defined is unloaded by the dynamic linker. The DSO is marked as
'unloadable' if it has a constructed thread_local object and marked as
'unloadable' again when all the constructed thread_local objects
defined in it are destroyed.
In order for the __kernel_get_tbfreq vDSO call to work the
INTERNAL_VSYSCALL_NCS macro needed to be updated to prevent it from
assuming an integer return type (since the timebase frequency is a 64-bit
value) by specifying the type of the return type as a macro parameter. The
macro then specifically declares the return value as a 'register' (or
implied pair) of the denoted type. The compiler is then informed that this
register (or implied pair) is to be used for the return value.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_ceil.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_finite.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_floor.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_frexp.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_isinf.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_isnan.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_llround.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_logb.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_lround.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_modf.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_nearbyint.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_remquo.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_rint.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_round.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_scalbln.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_scalbn.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_trunc.c: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/Implies: Add
ieee754/ldbl-opt/wordsize-64.
* sysdeps/powerpc/powerpc64/Implies: Add
ieee754/dbl-64/wordsize-64.
* Makerules (%.abilist): Add vpath on sysdep_dirs.
(check-abi-%): Remove AWK script prerequisite and explicit
abilist directory.
(check-abi): Rewrite to just diff the symlist with the abilist.
(config-tls, config-abi-config): Delete, no longer used.
(update-abi-%): Remove AWK script and explicit abilist directory.
(update-abi): Rewrite to simply compare and conditionally copy the
symlist and the sysdep abilist file. Remove update-abi-config
checks.
* abilist/ld.abilist: Remove.
* abilist/libBrokenLocale.abilist: Remove.
* abilist/libanl.abilist: Remove.
* abilist/libcrypt.abilist: Remove.
* abilist/libdl.abilist: Remove.
* abilist/librt.abilist: Remove.
* abilist/libthread_db.abilist: Remove.
* abilist/libutil.abilist: Remove.
* scripts/extract-abilist.awk: Remove.
* scripts/merge-abilist.awk: Remove.
* sysdeps/generic/libcidn.abilist: New file.
* sysdeps/generic/libnss_compat.abilist: New file.
* sysdeps/generic/libnss_db.abilist: New file.
* sysdeps/generic/libnss_dns.abilist: New file.
* sysdeps/generic/libnss_files.abilist: New file.
* sysdeps/generic/libnss_hesiod.abilist: New file.
* sysdeps/generic/libnss_nis.abilist: New file.
* sysdeps/generic/libnss_nisplus.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libanl.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libBrokenLocale.abilist: New
file.
* sysdeps/unix/sysv/linux/i386/nptl/libc.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libcrypt.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libdl.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libm.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libnsl.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libpthread.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libresolv.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/librt.abilist: New file.
* sysdeps/unix/sysv/linux/i386/nptl/libthread_db.abilist: New
file.
* sysdeps/unix/sysv/linux/i386/nptl/libutil.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libanl.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libBrokenLocale.abilist: New
file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libc.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libcrypt.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libdl.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libm.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libnsl.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libpthread.abilist: New
file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libresolv.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/librt.abilist: New file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libthread_db.abilist: New
file.
* sysdeps/unix/sysv/linux/x86_64/nptl/libutil.abilist: New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/ld.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libanl.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libBrokenLocale.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libc.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libcrypt.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libdl.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libm.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libnsl.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libpthread.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libresolv.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/librt.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libthread_db.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powercp32/fpu/nptl/libutil.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/ld.abilist: New
file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libanl.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libBrokenLocale.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libc.abilist: New
file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libcrypt.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libdl.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libm.abilist: New
file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libnsl.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libpthread.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libresolv.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/librt.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libthread_db.abilist:
New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libutil.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libanl.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libBrokenLocale.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libc.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libcrypt.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libdl.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libm.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libnsl.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libpthread.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libresolv.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/librt.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libthread_db.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libutil.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libanl.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libBrokenLocale.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libcrypt.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libdl.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libm.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libnsl.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libpthread.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libresolv.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/librt.abilist: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libthread_db.abilist:
New file.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libutil.abilist: New
file.
* sysdeps/unix/sysv/linux/sh/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libanl.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libBrokenLocale.abilist: New
file.
* sysdeps/unix/sysv/linux/sh/nptl/libc.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libcrypt.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libdl.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libm.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libnsl.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libpthread.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libresolv.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/librt.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libthread_db.abilist: New file.
* sysdeps/unix/sysv/linux/sh/nptl/libutil.abilist: New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libanl.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libBrokenLocale.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libc.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libcrypt.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libdl.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libm.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libnsl.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libpthread.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libresolv.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/librt.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libthread_db.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libutil.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/ld.abilist: New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libanl.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libBrokenLocale.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libc.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libcrypt.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libdl.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libm.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libnsl.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libpthread.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libresolv.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/librt.abilist: New
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libthread_db.abilist:
New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libutil.abilist: New
file.
This patch tries to organize the implies files for ppc, since there are
a number of processors and most of them are compatible with each other
(backwards compatible).
Having in mind that we start the search for processor-specific files in
the sysdeps/unix/sysv/linux tree
(sysdeps/unix/sysv/linux/powerpc/powerpc[32|64]/[processor]/fpu to be
exact), we would like to grab any linux-specific code from that tree
prior to going through the other tree (sysdeps/powerpc/...).
For that, i removed the Implies files that were originally inside the
fpu directories and placed then in the non-fpu directories (still inside
the unix/sysv/linux tree). If no processor-specific/linux-specific files
could be found, we "imply" the other tree's (sysdeps/powerpc/...) fpu
directory for that specific processor AND also the non-fpu directory for
that same tree.
If, again, no processor-specific code is found, we read another Implies
file that will point to the most compatible processor that we should
grab code from, and so on, until we reach the power4 processor.
So, in summary, the Implies files will live inside these directories
now:
* sysdeps/unix/sysv/linux/powerpc/powerpc[32|64]/[processor]
* sysdeps/powerpc/powerpc[32|64]/[processor]
Practical example of the order we will use to pick power6-specific code
with the new structure.
sysdeps/unix/sysv/linux/powerpc/powerpc[32|64]/power6/fpu ->
sysdeps/unix/sysv/linux/powerpc/powerpc[32|64]/power6 ->
sysdeps/powerpc/powerpc[32|64]/power6/fpu ->
sysdeps/powerpc/powerpc[32|64]/power6 ->
sysdeps/powerpc/powerpc[32|64]/power5+/fpu ->
sysdeps/powerpc/powerpc[32|64]/power5+ ->
sysdeps/powerpc/powerpc[32|64]/power5/fpu ->
sysdeps/powerpc/powerpc[32|64]/power5 ->
sysdeps/powerpc/powerpc[32|64]/power4/fpu ->
sysdeps/powerpc/powerpc[32|64]/power4 (from here, it'll go to the
generic path as usual)
I've noticed that sync_file_range is a stub on ppc/ppc64.
The kernel on these arches provides sync_file_range2 syscall with swapped
parameters.
The following completely untested patch ought to fix this.
