In cases where there might be a crash in the unwind library itself,
we need a method to avoid skipping these frames or we won't be able
to see the actual crash.
Added unit test for this behavior.
Bug: 74121887
Test: Ran unit tests on host and target.
Change-Id: I45825020c174016af39dd8ffdc67acb72a24ad4d
(cherry picked from commit 458f4e725d)
libbbacktrace changes:
- Completely rewrite the BacktraceOffline class to use the new unwinder.
- Modify the test data to save ucontext_t data instead of unw_context data.
- Convert the previous tests from unw_context data to ucontext_t data.
Bug: 65682279
Test: New unit tests pass in libunwindstack.
Test: All offline tests continue to pass.
Change-Id: I540345c304b20199d46deeb0349a0638a0f3ab2f
In order to support the offline unwinding properly, get rid of the
usage of non-fixed type uintptr_t from all API calls.
In addition, completely remove the old local and remote unwinding code
that used libunwind.
The next step will be to move the offline unwinding to the new unwinder.
Bug: 65682279
Test: Ran unit tests for libbacktrace/debuggerd.
Test: Ran debuggerd -b on a few arm and arm64 processes.
Test: Ran crasher and crasher64 and verified tombstones look correct.
Change-Id: Ib0c6cee3ad6785a102b74908a3d8e5e93e5c6b33
This is to help debugging different offline unwiding failures.
Bug: http://b/69383534
Test: run backtrace_test.
Change-Id: I5ed4837027a9f17d032925e97e9f5927161444b3
Add a static GetLoadBias method to the Elf object that only reads just
enough to get the load bias.
Add a method to MapInfo that gets the load bias. First attempt to get
it if the elf object already exists. If no elf object was created, use
the new static method to get the load bias.
In BacktraceMap, add a custom iterator so that when code dereferences
a map element, that's when the load bias will be retrieved if it hasn't
already been set.
Bug: 69871050
Test: New unit tests, verify tombstones have non-zero load bias values for
Test: libraries with a non-zero load bias.
Change-Id: I125f4abc827589957fce2f0df24b0f25d037d732
Add a mutex in MapInfo, and a mutex in Elf. Lock the creation of an Elf
file using the MapInfo mutex, and lock when calling Step, GetFunctionName,
or GetSoname since they can modify information in the object. It might
be beneficial to use a fine grained lock in the future.
Change the Maps object to contain a vector of MapInfo pointers rather
than the total objects. This avoids copying this data around.
Add a test to libbacktrace to verify that sharing a map while doing
unwinds in different threads works.
Add concurrency tests in libunwindstack to verify the locking works.
Add always inline to the RegsGetLocal arm and aarch64 functions. I had
a case where clang did not inline the code, so make sure this is specified.
Bug: 68813077
Test: New unit tests to cover the case. Passes all unit tests.
Test: Ran a monkey test while dumping bugreports and verified that
Test: no crashes in libunwind.
Test: Remove the locking and verified that all of the concurrenty tests fail.
Change-Id: I769e728c676f6bdae9e64ce4cdc03b6749beae03
Update the backtrace leak tests to share a map since this is the most
common way it will be used, and it runs much faster.
Remove the CreateNew functions, and references to them.
Remove benchmarks of CreateNew functions.
Test: Builds, ran new unit tests, ran art tests.
Change-Id: I4a25a412f1a74c6d43aebbebbf32ead20ead8f94
Correct for the number of skipped frames when unwinding with
libunwindstack.
Test: backtrace_test32 --gtest_filter="unwind_frame_skip_*"
Change-Id: I9528977104fde3c4ec792a6db1ada24ed571b867
If a function crashes by jumping into unexecutable code, the old method
could not unwind through that. Add a fallback method to set the pc from
the default return address location.
In addition, add a new finished check for steps. This will provide a method
to indicate that this step is the last step. This prevents cases where
the fallback method might be triggered incorrectly.
Update the libbacktrace code to unwind using the new methodology.
Update the unwind tool to use the new unwind methodology.
Add a new option to crasher that calls through a null function.
Create a new object, Unwinder, that encapsulates the a basic unwind. For now,
libbacktrace will still use the custom code.
Added new unit tests to cover the new cases. Also add a test that
crashes calling a nullptr as a function, and then has call frames in
the signal stack.
Bug: 65842173
Test: Pass all unit tests, verify crasher dumps properly.
Change-Id: Ia18430ab107e9f7bdf0e14a9b74710b1280bd7f4
- Change all load_base to load_bias in the test files.
- Add the test files to the backtrace_test.
- Add a function to get the path to the test libraries.
- Change aarch64 to arm64 for offline test code.
- Modify the offline tests so that they can be easily updated when
unwinding on any arch for any other arch is possible.
- Add tests of CreateNew for remote debugging.
Test: Ran unit tests on host and angler.
Change-Id: Id6c5afe73aeb2ac22463dd81f061799fcb1c178b
- Change the field name load_base to load_bias (which is what it really is).
- Add a rel_pc field so that callers do not need to compute it themselves.
- Remove the BacktraceMap::GetRelativePc() since nobody should need to
compute this themselves.
Bug: 23762183
Test: Compiles and unit tests pass (debuggerd, libbacktrace).
Change-Id: I2cb579767120adf08c407a58f3c487ee3f2b45fc
Also make backtrace_testlib.c C++.
Bug: 34468756
Test: Ran new unit test on host x86, host x86_64, angler (32 bit, 64 bit),
Test: fugu.
Change-Id: Ia810f596c2df56cd56e8ab17e6c19be0c48d737f
It's possible that a device map has memory controlled by a single entry
device driver. Thus, you can deadlock if a process is touching that
device memory and we try to unwind it and also touch that device memory.
Simply skip any attempts to step through, or get function names from
device memory maps.
Bug: 36130325
Test: Ran new unit tests, ran bionic unit tests, ran art ThreadStress.
Change-Id: Ibc62d7ec8106c619ee08968f05e04aea55d7cbfa
Some extra initialization needs to occur before calling the local/remote
GetFunctioneName.
Also, cleanup the test code a bit:
- Make all local functions static.
- Create a common function to create and finish remote processes.
- Remove unused function.
- Fix the formatting a bit by making it match clang format.
Test: Ran the unit tests.
Change-Id: I998bed1378d582df59fdf9263df6f208db5d795a
If the underlying local map changes, it's possible for multiple
threads to try and modify the map data associated with the UnwindLocalMap
object. Add a lock when generating the local map to avoid this problem.
In addition, add a read lock whenever any caller gets the maps iterator.
Updated all iterator callers to make this lock.
Bug: 29387050
Change-Id: Ie34822c3d8fd3bdb3dd126aeeb399969c36508c1
Remove the logging of an error if a thread disappears before the unwind
can begin. This can happen, so allow the caller to determine if this
is really a problem worth logging.
Bug: 27449879
Change-Id: Ie81718d53fb0e519fa0a7db9fd5f314b72bfa431
Sometimes, the new pss is significantly less than the stable pss. Do
not fail if this case occurs.
Change-Id: Ic7da87275a821818e375d05cac10e84c62710c5e
The check_unreadble_elf_* tests only create a readable map. I changed
libunwind to disallow unwinding through non-executable maps, so make
the maps executable too.
Bug: 26589772
Change-Id: Idbe6426ac4d3243779b819c8f1aebdcdacb0669f
Before, an anonymous map wound up printing the pc as relative.
Unfortunately, this meant that it was impossible to tell the actual
pc. The new code prints the map name as <anonymous:map_start> and
still prints the pc as relative.
In addition, add the start of the map for map names that begin with a
'[' character.
Bug: 25844836
Change-Id: Ie0b6149dde258fe13f0e5a3e5739d85374512f4b
The dlopen of a shared library in an apk results in large map offsets.
Unfortunately, the current way that the frame data is printed, it's
impossible to tell what the relative pc is relative to. With the
addition of the offset, it's possible to figure out what the relative
pc actually references.
Bug: 23348999
Change-Id: Ia51b669ea3f810158cfd0d71d9ae89bf9a3170d3
Upstream clang has a new diagnostic, '-Wmismatched-new-delete' to
generate a warning (that becomes an error with -Werror) when delete is
used to deallocate pointers created with 'new[]'. This patch fixes
'delete's that trigger this warning/error.
Change-Id: I7551e856b4b13bfae4cb78b5664d8652322683cf
Also simplifies the Darwin implementation of gettid, because
apparently libbacktrace had a better way of doing it.
Bug: 19517541
(cherry picked from commit 23f750b068)
Change-Id: I2f888e8ed7a2f5719973786cbcbb399a81867ee9
The BacktracePtrace::Read function crashes if the number of bytes to
read is less than the number of bytes needed to align the read to
a word_t boundary.
Fix this and add a test for this case.
Change-Id: I50808849ece44928f65dba1d25309e3885c829a2
(cherry picked from commit 944f417ccb)
The BacktracePtrace::Read function crashes if the number of bytes to
read is less than the number of bytes needed to align the read to
a word_t boundary.
Fix this and add a test for this case.
Change-Id: I50808849ece44928f65dba1d25309e3885c829a2
The new linker relocation packing support uses non-zero load bases,
so we better handle them properly.
Also print out the load base for a map if it's non-zero.
Bug: 20687795
(cherry picked from commit 329ed7dae4)
Change-Id: Ibc37d8c8bb032820dca4e7531184349ba6d402d2
The new linker relocation packing support uses non-zero load bases,
so we better handle them properly.
Also print out the load base for a map if it's non-zero.
Bug: 20687795
Change-Id: Iec2d1db2051e7b4a278c1dfa57d745128a7f2974
Also simplifies the Darwin implementation of gettid, because
apparently libbacktrace had a better way of doing it.
Change-Id: I9e14f9176b167405a5aaa5b8a0db0327c7126271
When doing a local unwind, do not include the frames that come
from either libunwind or libbacktrace.
Bug: 11518609
Change-Id: I0ec8d823aebbfa0903e61b16b7e5663f3fd65e78
The object hierarchy was confusing and convoluted. This removes
a lot of unnecessary code, and consolidates the BacktraceCurrent
and BacktraceThread code into BacktraceCurrent.
Change-Id: I01c8407d493712a48169df49dd3ff46db4a7c3ae
Included tests for this new feature.
Changed the NULLs to nullptr in backtrace_test.
Changed UniquePtr to std::unique_ptr in backtrace_test.
Change-Id: I92375465b8f8ba84589834cc162db5915bf1be81
The backtrace structure used to include a pointer to a backtrace_map_t
that represented the map data for a particular pc. This introduced a
race condition where the pointer could be discarded, but the backtrace
structure still contained a pointer to garbage memory. Now all of the map
information is right in the structure.
Bug: 19028453
Change-Id: If7088a73f3c6bf1f3bc8cdd2bb4b62e7cab831c0
Switch to the better supported pthread_cond to handle the Wait/Wake
functions.
Also, increase the number of simultaneous threads in the thread tests.
Bug: 18381207
(cherry picked from commit db44538387)
Change-Id: Id326a7a7b92cb61573def3f761597c40f3ef2f4b
This new version doesn't require any specialized thread
implementation, it uses the Current implementation to do its job.
In addition, it runs much faster when multiple threads are trying
to unwind at the same time since the global signal lock is held for
only a small amount of time. Even running through the threads one at
a time should be faster since it no longer requires two passes through
the unwound stacks.
The new code now allows multiple simultaneous unwinds of the
same thread.
Finally, add the ability to unwind from a ucontext_t passed in. This
functionality doesn't work for remote unwinds yet.
Change-Id: I4d181d7ca5ffd2acfd1686e668e6d21e36b425cb
The way libunwind handles local unwinds is different from remote unwinds,
so create a new map object to handle the differences.
Add new test to verify the map data is being generated correctly.
Add new tests to check for leaks.
Refactor the BACK_LOGW code into a single header file.
Change-Id: I01f3cbfc4b927646174ea1b614fa25d23b9b3427
Update to handle the new optimized way that libunwind works.
In addition, a small refactor of the BacktraceMap code.
A few new tests of for good measure.
Change-Id: I2f9b4f5ad5a0dfe907b31febee76e4b9b94fb76f
This includes removing the map_info.c source and replacing it with the
BacktraceMap class to handle all map related code.
Change all callers of libbacktrace map functionality.
Also modify the corkscrew thread code so that it doesn't need to build
the map twice (once in the corkscrew format and once in the libbacktrace
format).
Change-Id: I32865a39f83a3dd6f958fc03c2759ba47d12382e
Use the libbacktrace C++ interface instead of the C interface in debuggerd.
Reformat the debuggerd code to be closer to Google C++ style.
Fix all debuggerd casts to be C++ casts.
Add a frame number to the frame data structure for ease of formatting and
add another FormatFrameData function.
Change the format_test to use the new FormatFrameData function.
Modify all of the backtrace_test to use the C++ interface.
Change-Id: I10e1610861acf7f4a3ad53276b74971cfbfda464
Use a bit better name for this. The other name was a bit confusing.
Change-Id: I1261f2ee3854a9c8b82133ad0bfbbbe48b43c9ac
(cherry picked from commit 242b1a8c7a)
Conflicts:
libbacktrace/Backtrace.cpp
The old code was essentially trying to be C++ in C and was awkward. This
change makes it all objects with a thin layer that C code can use.
There is a C++ backtrace object that is not very useful, this code will
replace it.
This change also includes moving the backtrace test to a gtest, and adding
coverage of all major functionality.
Bug: 8410085
Change-Id: Iae0f1b09b3dd60395f71ed66010c1ea5cdd37841
