Detect if current frame is a signal frame by checking for preceeding
syscall instruction. For signal frames, update the cursor correctly
from user context before calling dwarf_step.
This is similar to commit c90a2e02b3
"Mark run-ptrace-mapper and run-ptrace-misc as XFAIL on MIPS".
Starting with 2.6.39, ARM Linux returns -EIO for PTRACE_SINGLESTEP, so
we need to mark this as XFAIL for ARM too.
The Linux commit that changed this is
commit 425fc47adb5bb69f76285be77a09a3341a30799e
Author: Will Deacon <will.deacon@arm.com>
Date: Mon Feb 14 14:31:09 2011 +0100
ARM: 6668/1: ptrace: remove single-step emulation code
see: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=425fc47adb5bb69f76285be77a09a3341a30799e
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Due to a bug in the gold linker[1], the .eh_frame and .eh_frame_hdr
sections contains garbage. When dwarf_extract_proc_info_from_fde tried
to look up the begin of the CIE subsection, it would underflow the
.eh_frame segment, resulting in a crash[2].
This patch avoids that crash by checking whether the CIE pointer is
located after the begin of the .eh_frame section. The variable "base"
was misused in various places as a boolean (decode as .debug_frame or
decode as .eh_frame). These instances have been renamed to
is_debug_frame where applicable.
Tested on Linux x86_64.
[1]: https://sourceware.org/bugzilla/show_bug.cgi?id=17639
[2]: http://lists.nongnu.org/archive/html/libunwind-devel/2014-11/msg00009.html
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
- Add autogen.sh to bootstrap autotools generation
- Make generation of man pages optional, and check for
availibity of latex2man if documentation is requested.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Signed-off-by: Arun Sharma <asharma@fb.com>
Set local_addr_space.big_endian flag according to current target
endianness. Before it was set by memset to 0, which corresponds
to little endian and it worked perfectly fine for aarch64.
But it breaks aarch64_be because dwarf_readu16, dwarf_readu32,
etc functions do not read values correctly since they operate
with wrong idea about current target endianness.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Introduce support for aarch64_be, aarch64 big endian, target.
We would like to reuse all code that was done for aarch64
(little endian) target. So we do similar thing that is done
for ARM v7 (arm) target for any aarch64* arch we set it
just to aarch64.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Though PTRACE_SINGLESTEP is defined on MIPS Linux, the kernel does
not support that kind of request. The ptrace call failed and sets
errno to EIO and paused process is not resumed. In case of
run-ptrace-mapper and run-ptrace-misc this leads to hanged execution
because next call to wait4 never returns.
This change adds run-ptrace-mapper and run-ptrace-misc to the list
of 'expected failed' tests on MIPS targets.
Signed-off-by: Simon Atanasyan <simon@atanasyan.com>
We've just traced a large memory increase to that patch (Google ref:
b/18069427).
It appears that labs() was there for a good reason.
Sorry about that :-(
For the curious:
unsigned long u1 = ~0UL;
unsigned long u2 = labs(u1);
assert(u1 != u2); // labs on unsigned *may* have an effect, despite
what Clang says.
Attached patch suppresses the Clang warning, while still keeping the
original behavior (which I believe to be correct).
Thanks,
--
Paul Pluzhnikov
After the following change the Lrs-race test case starts to intermittently
fails:
eac65dc Add basic support for the QNX operating system
When we include "config.h" into the "libunwind_i.h" we undefine
the HAVE___THREAD macro in a few lines below in #include "config.h"
pragma. The change eac65dc includes "config.h" into the "dwarf.h"
but forgets to undefine HAVE___THREAD. So now this macro has inconsistent
state among the code. Somewhere it is defined, somewhere not. In particular
it becomes defined in the mi/Gset_caching_policy.c and we do not replace
UNW_CACHE_PER_THREAD caching policy by the UNW_CACHE_GLOBAL.
The fix is rather dirty. It adds the code to undefine HAVE___THREAD in
the "dwarf.h" like we do that in the "libunwind_i.h". Probably the ideal
solution should fix per-thread caching implementation or turned it off
at all on platforms where it is not completely and correctly supported.
Signed-off-by: Simon Atanasyan <simon@atanasyan.com>
Hi,
there is a compilation issue with Clang and latest libunwind - It's
about "typedef struct unw_tdep_save_loc" and one more struct:
include/libunwind-x86_64.h:111:9: error: empty struct has size 0 in C,
size 1 in C++ [-Werror,-Wextern-c-compat]
The solution is very simple:
Greetings,
Roman reports that Clang warns on unnecessary calls to labs():
taking the absolute value of unsigned type 'unw_word_t' (aka
'unsigned long') has no effect [-Werror,-Wabsolute-value]
Since rs->reg[...].val is unw_word_t and unsigned on all platforms,
this patch removes the unnecessary calls to labs().
Tested on Linux x86_64, no regressions.
Thanks,
--
Paul Pluzhnikov
Fix returning the name of the function containing the frame PC,
for the non-interrupted frames. The symbol lookup code should
take use_prev_instr value into account, otherwise it could return
the name of the function adjacent to the caller.
Mark frames which are unwound with the frame-chain walker or
syscall frame code, as non-interrupted. The return PC in the frame
points to the instruction after the call.
For some architectures, -lgcc and -lgcc_s are not equivalent. On ARM for
example, libgcc_s.so.1 contains some symbols needed by libunwind which
are not present in libgcc.
This causes the following link error when building the X.Org X server
with libunwind support:
CCLD Xorg
/usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr0'
/usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr1'
Linking against libgcc_s explicitly solves this problem.
Signed-off-by: Thierry Reding <treding@nvidia.com>
We already have the value computed based on the executable. Furthermore,
debuginfo need not have valid program header table, thus the result
might be bogus.
Signed-off-by: Martin Milata <mmilata@redhat.com>
When JITs generate code without unwind information, it may be possible
to continue unwinding via RBP chaining. However, we currently disallow
RBP==RSP condition even though we can make forward progress.
Relax the check a bit in the code where we switch from one type of
unwinding to another to handle this situation. JIT authors
are encouraged to use the dynamic unwind info registration API when
the underlying platform supports it.
Signed-off-by: Kevin Modzelewski <kmod@dropbox.com>
The attached patch simply modifies the Debug statements for aarch64 to use
%lx instead of %x. Tested by compiling for aarch64 using a cross-compiler.
Signed-off-by: Christopher Ferris <cferris@google.com>
The coredump/elf32/elf64/elfxx libs use lzma funcs but don't link against
it. This produces sub-shared libs that don't link against lzma and can
make the linker angry due to underlinking like so:
libtool: link: x86_64-pc-linux-gnu-gcc -O2 -march=amdfam10 -pipe -g \
-frecord-gcc-switches -Wimplicit-function-declaration -fexceptions \
-Wall -Wsign-compare -Wl,-O1 -Wl,--hash-style=gnu \
-o .libs/test-coredump-unwind test-coredump-unwind.o \
../src/.libs/libunwind-coredump.so ../src/.libs/libunwind-x86_64.so
../src/.libs/libunwind-coredump.so: error: undefined reference to 'lzma_stream_footer_decode'
../src/.libs/libunwind-coredump.so: error: undefined reference to 'lzma_index_buffer_decode'
../src/.libs/libunwind-coredump.so: error: undefined reference to 'lzma_index_size'
../src/.libs/libunwind-coredump.so: error: undefined reference to 'lzma_index_end'
../src/.libs/libunwind-coredump.so: error: undefined reference to 'lzma_index_uncompressed_size'
../src/.libs/libunwind-coredump.so: error: undefined reference to 'lzma_stream_buffer_decode'
collect2: error: ld returned 1 exit status
So add LIBLZMA to the right LIBADD for each of these libraries.
URL: https://bugs.gentoo.org/444050
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Ubuntu's libc-bin (2.15-0ubuntu20.2) on x86_64 uses DW_CFA_val_expression
in describing the pthread spinlock operations __lll_unlock_wake() and
__lll_lock_wait(). libunwind 1.1 doesn't understand that opcode and
so backtraces from those operations are truncated.
This changeset adds basic support for it, by adding a new type to
dwarf_loc_t that describes the register's actual contents rather than
its location. I've only implemented the new type for x86_64, and
stubbed it out for all other architectures -- it looks like a lot
of that code is duplicated so oughtn't to be that hard, but I don't
have test cases for them.
Tested that DW_CFA_val_expression works on x86_64 (by using
https://code.google.com/p/gperftools/ on a lock-heavy program).
Build-tested on x86, x86_64 and arm. The unit tests don't pass for me
on any of those archs, but this cset doesn't break anything that was
passing before.
Signed-off-by: Tim Deegan <tjd@phlegethon.org>
This patch adds support for the powerpc64le-linux platform. It consists
of two main features:
- Support little-endian byte order
This is done via a "big_endian" member of struct unw_addr_space,
which is evaluated by common code via the dwarf_is_big_endian
macro, and also in endian-aware code in unw_is_signal_frame.
- Support the ELFv2 ABI
This is done via an "abi" member of struct unw_addr_space. This
is currently only needed in tdep_get_func_addr, since the ELFv2
ABI does not use function descriptors.
Both new members are initialized in unw_create_addr_space and
ppc64_local_addr_space_init, following the mips precedent.
Since ppc32 and ppc64 now no longer share the unw_create_addr_space
implementation, the file is duplicated from the ppc directory into
ppc32/ppc64.
Tested on powerpc64-linux and powerpc64le-linux. Support on LE
seems to be as good as existing BE support; I have not attempted to
fix the existing shortcomings of PPC support that already cause a
number to tests to fail due to unimplemented features.
Signed-off-by: Ulrich Weigand <uweigand@de.ibm.com>
On systems where the system compiler supports Altivec by default,
the libunwind Makefile will attempt to build an extra test case
ppc64-test-altivec. Unfortunately, the link step will fail since
the Makefile does not actually link against the libunwind library.
Fixed by adding the appropriate LDADD macro.
Signed-off-by: Ulrich Weigand <uweigand@de.ibm.com>
The ppc64 implementation of tdep_get_func_addr would crash when
attempting to retrieve the address of a function in a shared
library. The problem was that it needs to dereference the
function descriptor, but common code was passing the *unrelocated*
adddress of the descriptor to the tdep_get_func_addr routine.
Instead, common code would attempt to relocate the *result* of
tdep_get_func_addr, which is also wrong: the ppc64 implementation
reads the function address from the in-memory copy of the
descriptor, which is already relocation and contains the final
address.
This patch fixes the problem by relocating the descriptor address
before passing it to tdep_get_func_addr, instead of relocating
the result of tdep_get_func_addr. Since ppc64 is the only
non-trivial implementation of tdep_get_func_addr, this cannot
affect any other platform.
Signed-off-by: Ulrich Weigand <uweigand@de.ibm.com>
The dwarf_eval_expr routine uses macros push, pop, and pick to
manipulate the DWARF expression stack. When these macros are
nested, e.g. in the implementation of DW_OP_dup:
push (pick (0));
the combination can lead to unfortunate results.
In particular, when substituting into:
do {
if (tos >= MAX_EXPR_STACK_SIZE)
{
Debug (1, "Stack overflow\n");
return -UNW_EINVAL;
}
stack[tos++] = (x);
} while (0)
a value of "x" that makes use of "tos" (as instances of the
pick or pop macros do), the resulting expression will both
use and modify tos without an intervening sequence point,
which is undefined behavior according to the C standard.
And in fact with current GCC on PowerPC, this leads to a
miscompilation of the DW_OP_dup implementation.
This patch fixes the problem by assigning "x" to a
temporary variable before modifying tos.
Signed-off-by: Ulrich Weigand <uweigand@de.ibm.com>
liblzuma used in decoding MiniDebuginfo is not listed in
libunwind.pc.
Changes in version 2 of patch:
* Don't check HAVE_LZMA. It is redundant.
* Make liblzma as private libraries in use.
Both are suggested by Mike Frysinger <vapier@gentoo.org>.
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
pkg-config metadata template files are missing Cflags keyword
which is required to properly compile against libunwind using
PKG_* autoconf macros
Acked-by: Mike Frysinger <vapier@gentoo.org>
The DWARF code allocates its unwind_info objects out of a
memory pool. The code which frees the object therefore calls
the mempool freeing code. However, there are cases where the
free code will be run with an unwind_info that was allocated
through a different mechanism (e.g. an ARM exidx table entry).
In these cases, the object should not be freed through the
mempool code.
To correct this, a check was added to ensure that the unwind_info
is of the appropriate type before passing the object along to the
mempool to be freed.
This change adds some special cases to allow libunwind to compile
for QNX.
* QNX's copy of <elf.h> and <link.h> reside in sys/ instead. To deal
with this, an AC_CHECK_HEADERS() was added to check for the files
in both locations.
* Similarly, QNX does not have <endian.h>. In cases where the file is
not found, logic was added to refer to QNX-specific macros to determine
endianness.
* The QCC compiler, which is a wrapper around GCC, cannot handle some
standard GCC options. Therefore, logic was added to check for QCC,
and when it is found, to suppress the use of -lgcc, and to express the
option -nostartfiles as -Wc,-nostartfiles instead, which is correctly
passed on to the underlying GCC.
* Finally, the support file os-qnx.c was added, patterned after the existing
os-*.c files. Only local image lookup is currently supported (see the
comments for more information), but this is sufficient for QNX, since
ptrace is not supported there anyway, and that is the only case where the
function is required to do remote image lookup.
Change-Id: Ie7934f94a7317bdde59335f2acd4c3a97c0384c1
During the install, symlinks are added from libunwind-<arch> to
libunwind-generic. However, on platforms that don't support
symlinking (such as Windows), the $(LN_S) macro is defined
as 'cp -p' instead. This works fine, except that since the
target of the symlink is a relative path, the copy will only
succeed if the current directory is the directory that contains
the file.
The solution to this problem suggested in the Autotools manual
(see http://www.gnu.org/software/automake/manual/automake.html#Extending)
is to simply cd into the correct directory first. This patch
makes that change for the symlinks that are being made during install.
[ edit: use relative path for the link name as well ]
The crasher test is used as part of the coredump test suite,
but is being built regardless of whether that support has been
configured or not. This patch changes the build so that it is
only built when coredump support is enabled.
Currently, libunwind-setjmp is built whenever local unwinding is
built. This patch adds an explicit flag to control it instead.
The default if not specified is to follow the old behavior.
This change adds a manual override to control building of the ptrace
library, similar to the existing --enable-coredump option. The
default is set based on the existence of sys/ptrace.h, allowing it
to be automatically disabled for platforms that do not have ptrace.
