Recently, the maps for an elf in memory might show up looking like:
f0000-f1000 0 r-- /system/lib/libc.so
f1000-f2000 0 ---
f2000-f3000 1000 r-x /system/lib/libc.so
f3000-f4000 2000 rw- /system/lib/libc.so
The problem is that there is logic in the code that assumed that the
map before the execute map must be the read-only map. In the case
above, this is not true. Add a new prev_real_map that will point
to the previous map that is not one of these empty maps.
This will fix the backtraces that look like this:
#00 pc 0000000000050d58 /apex/com.android.runtime/lib64/bionic/libc.so!libc.so (offset 0x50000) (syscall+24) (BuildId: 5252408bf30e395d49ee270b54c77ca4)
To get rid of the !libc.so and the offset value, which is not correct.
Added new unit tests to verify this.
Added new offline test which an empty map between read-only and execute
map. Before this change, the backtraces had lines like
libc.so!libc.so (offset XXX) would be present.
Bug: 148075852
Test: Ran unit tests.
Change-Id: Ie04bfc96b8f91ed885cb1e655cf1e346efe48a45
The function StepIfSignalHandler assumed that the rel_pc passed
to it was actually an elf offset. A new version of clang created a libc.so
that has a load bias, so tests unwinding through a signal handler
would fail on arm. On other ABIs, there is unwind information that could
be used instead, so the unwind still worked.
The fix is to subtract the load bias from the rel_pc to get an elf
offset to pass to the Register StepIfSignalHandler functions. Change all
of the Register funtions to make it clear what the first parameter means.
Add a unit test for this new code. Also, add an offline test for
this case.
Bug: 145683525
Test: Ran unit tests using the new clang and the old clang.
Change-Id: I3e249653b79bcad6d3a56411a7911fde4888e9d6
No longer require that NO_LIBDEXFILE_SUPPORT be defined or not
defined when including the header files. Move all of the different
behavior to the implementation, and keep all of the classes the
exact same whether dexfiles are supported or not.
Bug: 144470551
Test: Ran libunwindstack unit tests, libbacktrace unit tests, and
Test: debuggerd unit tests.
Test: Ran host art 137-cfi tests.
Change-Id: I4a04cfbc5d4f1bf765ef154881046c85057006c8
The bias for the PT_GNU_EH_FRAME was using the paddr instead of vaddr.
This doesn't match the way the load bias is calculated, which always
use vaddr - offset, so change to use vaddr.
Found on an old x86 device that has a vdso that sets vaddr differently
from paddr.
Add a new offline test to catch this case and update the elf interface
unit tests.
Also, fix a small bug in the unwind_for_offline tool.
Bug: 142365899
Test: Unit tests pass.
Change-Id: I5f0bf062dd8ee45aa8553189ba493ec962e0b059
The original code assumed that the load bias in the program headers
would be exactly the same as in eh_frame/eh_frame_hdr/debug_frame.
This isn't guaranteed, so add a section bias for use when creating
a DwarfSection. In addtion, make the load bias and section bias
a signed value. There is no reason that this value needs to be positive,
so don't force it to be.
Add a new offline test that has a different load bias in eh_frame than
in the executable load.
Add additional unit tests to verify the load bias values are set properly.
Clean up the tests in ElfInterfaceTest, making all tests names follow the
same convention.
Bug: 141888859
Bug: 142094469
Test: New units and old unit tests pass on host and taimen.
Change-Id: Ib878123ab5545f0f315c749cfe0d27b012d873ee
Avoid accessing nullptr of already deleted entry.
Add new unit tests that pass with the fix and fail without.
Test: fixes unwinding in ART gcstress tests
Test: All unit tests pass.
Change-Id: Ideb00e2adc899904dd6aeb5dad3fb6fad150322d
Created a special target, libunwindstack_unit_test, that doesn't
include the test that dlopen's a shared library. It appears atest
doesn't understand how to handle the require keyword.
Also, move the shared library into the libunwindstack_test directory
itself.
Test: Ran atest libunwindstack_unit_test.
Change-Id: I967919b1d74a08669b61d0363d80861685725609
Add a specific test that __libc_init is the last frame in a stack
when run on device. In addition, it verifies that the return address
register is marked as undefined given the unwind.
Bug: 140008396
Test: New unit test passes on arm/arm64 (taimen device).
Test: New unit test passes on x86 (cuttlefish).
Test: New unit test passes on x86_64 (modified bionic/tests/run-on-host.sh)
Change-Id: Iefc151a7dbf52ab083c2bb78bad3d38b4e9e1254
Modify the MapInfoCreateMemoryTest to work in the isolated mode.
Test: Ran unit tests on host/target.
Change-Id: I84e01d96e852acd813e0f203b4a207cfaf8ca556
The previous versions of the libc++ demangler crashed on bad input.
However, the new version passes a fuzzer and has a lot of tests. Since
it's more complete than the local demangler, use it instead.
Modified the expected output of an offline test since the new demangler
handles a case that didn't work before.
Verified that the time it takes for the check_for_leak tests did not
change after this.
Bug: 136138882
Test: Ran the unit tests.
Test: Verified the __cxa_demangle function passes the fuzzer when run for
Test: hours. Both the 32 bit and 64 bit version of __cxa_demangle were
Test: fuzzed using external/libcxxabi/fuzz.
Change-Id: I10c06b589d57c36d89dbecba020b1ef2da69634a
Update the entries only when the list is modified by the runtime.
Check that the list wasn't concurrently modified when being read.
Bug: 124287208
Test: libunwindstack_test
Test: art/test.py -b --host -r -t 137-cfi
Change-Id: I87ba70322053a01b3d5be1fdf6310e1dc21bb084
The elf_start_offset field in a map_info was not set in one path.
Added new offline test for this, and update a few unit tests.
Bug: 128442792
Test: New unit tests pass.
Change-Id: I2c6ac1b5271a99aa0e8c4b6342a5970199185112
It should be dlopen'ed lazily by libdexfile_support now.
Also change debuggerd_test to not link libunwindstack and its dependencies
statically - the static libs can overlap with the dynamic ones.
Test: mmma system/core/debuggerd/
Test: atest debuggerd_test
Test: mmma system/core/{libunwindstack,libbacktrace}, run host gtests (cannot get atest to work)
Bug: 124827589
Bug: 123186083
Change-Id: I9e7bf9bcbae499af4e1be4c9854bce441e2a7b55
These tests are meant to replace the leak check tests from libbacktrace.
Bug: 120606663
Test: Ran tests on host and target.
Change-Id: I928b199304afc36b4bac78e9a2cd688b6f2910b9
Change the GetBuildID function to return a std::string.
Added benchmark to check how long it takes to get the build id from
a file versus an elf object.
Added a way to get an elf without passing in a valid process_memory and
added tests for this.
Test: New unit tests.
Change-Id: I3029019767e0181c758d611fe635bc1bf72d6e8e
This object is able to be easily used from other code and can be used
to replace the libbacktrace calls in other parts of the platform.
Also, demangle the function names when calling FormatFrame.
Bug: 120606663
Test: Unit tests pass, debuggerd using this code directly passes unit
Test: tests.
Change-Id: Ifd8cf9bdd89174c1736810711d20e9f37f29b1bf
Also remove some tests for implementation details in the libdexfile API that
are now covered by unit tests there (http://r.android.com/867370).
Test: mmma system/core/{libunwindstack,libbacktrace} and run host gtests
Bug: 119632407
Change-Id: Ie731bb929a564de56ce1c78385da12a43d0954ff
This reverts commit 444e23d2fc.
The rest of the topic doesn't need to be reverted.
Reason for revert: Breaks renderscript on marlin and sailfish.
Test: Manual repro of http://b/121110092#comment1 on reported branch
Test: "atest CtsRenderscriptTestCases" on that branch
Test: mmma system/core/{libunwindstack,libbacktrace}, run host gtests
Test: Make image, flash, and reboot device.
Bug: 121110092, 119632407
Change-Id: If1976b19ce386c95bc5bd4fd6d523745c167de18
When a shared library is loaded directly from an apk, the new way the
linker splits a shared library into a read-only and execute segment
broke unwinding. Modify the code to handle this case.
Other changes:
- Modify the algorithm for finding read-only map entries. Before, the code
would search the entire map for the closest offset. Now it simply looks
at the previous map. I did this because the old code was too lenient and
might still work even if the linker changes. I want this to break if the
linker behavior changes so that I can analyze the change.
- Update the tools to use PTRACE_SEIZE instead of PTRACE_ATTACH since
PTRACE_ATTACH doesn't work in all cases.
- Small refactor of the GetFileMemory function.
- Add new unit test cases and new offline unwind test cases.
Bug: 120618231
Test: Ran new unit tests, ran original failing test.
Change-Id: I4bade55cf33220d52f1d5e9b0cbbbcc8419669d4
If multiple threads are unwinding at the same time, new maps that contain
the global variables for dex files and jit information are created. This
leads to threads creating more new maps that then get searched, then
more maps, then more searching until virtual address space exhaustion.
Fix this so that we only search maps that have a corresponding rw map that
could contain the global memory.
Small refactor to combine the code to search for global variables into
one class that both classes inherit from.
Modify unit tests for the new pattern checking.
Bug: 117761427
Test: Ran unit tests for libunwindstack/libbacktrace/simpleperf.
Test: Ran art 004-ThreadStress that used to fail.
Change-Id: I837ca6b9d0383100079de090bc7d019598e0cdfe
The rosegment linker option results in two maps containing the elf data
existing. One is an execute map where the code lives, and the other is the
read-only segment which contains the elf header information. If the file
backing a shared library in memory is not readable, then the new code
will attempt to find the read-only map that has the same name as the
current execute segment, and that is at offest zero in the file.
Add new unit tests for this functionality.
Add the missing MapInfoCreateMemoryTest.cpp to the list of tests.
Bug: 109657296
Test: Pass new unit tests.
Test: All unit libbacktrace/libunwindstack tests pass with rosegment enabled.
Change-Id: If8f69e4a067d77b3f2a7c31e2e5cd989a0702a8c
It turns out that for the dwarf information, if a FDE indicates it's pc
relative, then pc has to be incremented by the load bias. If not, then
it should not be incremented.
Previously, the code always subtracted load bias values from pcs, and assumed
that all fdes were incremented by load bias values. The new code actually
reads the fdes and adjusted the pcs in the fde and in the eh frame hdr so
that load bias values are already handled properly.
In addition, add dumping of arm exidx values in unwind_reg_info. This allowed
verifying that the debug frame in those elf files was being handled properly.
Added a new unit test that only has a debug frame that has a non-zero load
bias and has fde entries that do not have pc relative encoding.
Fix a couple of other small bugs.
Bug: 109824792
Test: All libbacktrace/libunwindstack unit tests pass.
Test: Ran ART 137-cfi test and 004-ThreadStress.
Test: Verify that displaying the fde start and end pc actually match the
Test: real data for fde that have pc relative set, and that don't.
Test: Verified that the unwind information for arm exidx matches the
Test: debug frame data.
Change-Id: I707555286b5cb05df9f25489e8c5ede753cfe0fb
adbd (and its dependencies) are marked as recovery_available:true so
that recovery version of the binary is built separately from the one for
system partition. This allows us to stop copying the system version to
the recovery partition and also opens up the way to enable shared
libraries in the recovery partition. Then we can also build adbd as a
dynamic executable.
Bug: 79146551
Test: m -j adbd.recovery
Change-Id: Ib95614c7435f9d0afc02a0c7d5ae1a94e439e32a
This object is for doing many local unwinds across different threads
at any point during a program's execution.
Also add LocalUpdatableMaps that will re-read the maps data under certain
circumstances.
This first version does not support jit or dex pc data.
Bug: 74361929
Test: Ran unit tests.
Change-Id: I790662366d3fed677f31b3288182950c494de9ad
Extend the debug support from the host library to host tools.
Test: mmma system/core/libunwindstack
Change-Id: Ib6ea5f021d6b8139c545eaa2e6b1675befa4d3bd
The new lld linker uses all non-zero offset executable maps. There was
a bug when trying to find if the stack is in a signal handler that caused
the code to read the wrong place in the elf. Fixed by not adding the elf
offset to the relative pc.
Also fixed the unwind_for_offline tool to dump multiple stacks if necessary.
Added new offline unit test that would have failed with the old code.
Bug: 79936827
Test: Ran unit tests and libbacktrace unit tests.
Test: Dumped backtraces of system pids.
Test: Ran 137-cfi art test.
Change-Id: Iaca8c18c2a314902e64c3f72831234297e8dcb1b
Add test and benchmark.
Also switch libbacktrace, libunwindstack, libmemunreachable
to use libprocinfo for map file reading.
The benchmark shows using libprocinfo speeds up map file reading
in libbacktrace and libunwindstack 18% - 36% on walleye.
Bug: http://b/79118393
Test: run procinfo_test.
Test: run libunwindstack_test.
Test: run libbacktrace_test.
Test: run memunreachable_test.
Change-Id: Icf281c352f4103fc8d4ba6732c5c07b943330ca1
Use this for offline stack data so that it's not necessary to
copy any data around.
Add unit tests for the new object.
Bug: 77258731
Bug: 74354410
Test: Ran libunwindstack/libbacktrace unit tests.
Change-Id: I9b0f25d9520c96e64aedef5f295423c60ddb3488
Changes:
- Add a new flag to the libbacktrace and libunwindstack map data.
- Modify the unwinder to handle this map to use the raw pc when stepping.
- Add new unit tests for this case.
Bug: http://b/73127105
Test: Run simpleperf to unwind through jit symfiles.
Test: Run new unit tests.
Test: Run 137-cfi test on host.
Change-Id: I10bc0410680accc6d35fe51e9f1098911f667e01
There are a few places where it is assumed that this register is
set to the cfa value when interpreting DWARF information.
Add a testcase for unwinding art_quick_osr_stub on ARM.
Bug: 73954823
Test: Ran libunwindstack/libbacktrace unit tests.
Test: Random debuggerd -b of process on a hikey.
Test: Ran the 137 art test on host.
Change-Id: Ida6ccdc38c3cfeea6b57fe861a0cc127b150b790
Thanks to David Sehr's recent work the isolation is no longer needed.
Bug: 72216369
Test: backtrace_test
Test: libunwindstack_test
Test: testrunner.py -t 137
Change-Id: I0f430e0c18bdbc83c5584a2461ebbcc7eeb91313
Move the files out of runtime, leaving unfortunate dependences still
there on runtime/base (for the moment). Also separates the build logic
into two Android.bp files.
Bug: 22322814
Test: make -j 50 test-art-host
Change-Id: I54b06f035034e7564480cd5d4c33c4f62785682d
- Add a new tool that can dump the register information given a pc.
- Add a new offline unwinder test that fails without this change.
- Update unit tests.
- Refactor offline unwind tests to make it easier to add tests.
Bug: 73048324
Test: Passes new unit tests.
Test: Passes libbacktrace unit tests.
Test: Ran debuggerd -b on random processes.
Change-Id: If6c70a044299505c2274ae6888b35bf9ac34b74b
Shrink a few files that are huge by removing all of the .debug_XXX
sections except .debug_frame since they aren't used.
Rename all of the arm32 to arm and x86_32 to x86.
Test: All unit tests pass.
Change-Id: Ia0f0baadf2a7fbc42a544aff2f14d5ed5f9287b7
Fixes cdex which was recently changed to have shared data section,
which means the DEX PC cannot be used to find the right symbol,
as the bytecode is no longer within the dex file, and in-fact,
we might have to scan multiple dex files to find the method.
Bug: 72520014
Test: testrunner.py --host --cdex-none -t 137
Test: testrunner.py --host --cdex-fast -t 137
Test: All unit tests pass.
Change-Id: I80265d05ad69dd9cefbe3f8a75e4cd349002af5e
Test: Compiles, all unit tests pass.
Test: Ran 137-cfi art test in interpreter and verified interpreter
Test: frames still show up.
Change-Id: Icea90194986faa733a873e8cf467fc2513eb5573
- Be a little more lenient when reading the cies/fdes. If next entry data
winds up incorrect, don't fail, simply stop processing the entries. This
only applies when reading all of the cies/fdes at once.
- Fail to init an eh_frame with no entries and fallback to assuming the
eh_frame has no header instead.
- Change the step to always try debug_frame first which has the most
accurate information.
- Add small unit tests and a couple of offline unit tests to verify
this behavior.
These changes are needed to support offline unwinding since it depends
on this new behavior.
Bug: 65682279
Test: Ran new unit tests.
Change-Id: I3529f1b0c8e14cd7409494e5de2f3c9e78d0855e
