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16 commits

Author SHA1 Message Date
David Srbecky
b9cc4fbb26 Revert "Check for data races when reading JIT/DEX entries."
This reverts commit 85b5fecec9.

Reason for revert: Breaks ART tests, reverting to investigate.

Change-Id: I1bb905407e87cbd4f832646651133a9caf6fcfc8
2019-04-05 18:23:32 +00:00
David Srbecky
85b5fecec9 Check for data races when reading JIT/DEX entries.
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
2019-03-29 14:01:32 +00:00
Christopher Ferris
eb0772ff4a Add support for UnwinderFromPid object.
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
2019-01-16 15:13:25 -08:00
Christopher Ferris
01040b10b2 Fix handling of ro segments for embedded libs.
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
2018-12-11 19:16:29 -08:00
Christopher Ferris
7747b60faa Load dex files from ART-specific data structure.
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
2018-02-02 15:03:00 -08:00
Christopher Ferris
d70ea5ea85 Move dex pc frame creation into libunwindstack.
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
2018-01-31 14:19:42 -08:00
Christopher Ferris
98984b41da Add support for getting a dex pc.
Changes:
- Change the register type from int16_t to uint32_t for the location data
  and the Eval processing. This is because the special dex pc is > 65535.
- Add the ability for Dwarf register location information to point to a
  register that is itself a Dwarf location register.
- Add dex_pc to the frame information.
- Modify the unwind tool to print the dex pc if non-zero.

This does not implement the printing of the dex information in anything
but the unwind tool. It's not the final form of this printing.

Bug: 72070049

Test: Ran new unit tests.
Test: Dumped stack while in interpreter running 137-cfi art test and
Test: verified dex pc is set to non-zero.
Change-Id: I6ce8a6b577fb4f92abacbd433b1f68977e272542
2018-01-17 19:18:00 -08:00
Christopher Ferris
150db124f3 Add ability to read jit gdb data.
Changes:
- New JitDebug class to handle all of the jit gdb interface.
- Add unit tests for all, along with new offline test using debug data.
- Add new Memory type called MemoryOfflineParts that has multiple
  MemoryOffline objects to support the offline test.
- Update the tools to use the JitDebug object.
- Modify libbacktrace to use the JitDebug, but only looking in libart.so
  and libartd.so.
- Change the Format32Bits to Is32Bit since it's more accurate and I use
  it in a different context where original name didn't make sense.
- Add a new function to find global variables in an elf file
  (GetGlobalVariable).
- Add a new function to determine if a pc is valid for this elf (IsValidPc).

Bug: 68396769

Test: Ran new unit tests. Added new offline test that uses jit debug data.
Test: Ran art test that generates jit data and verified a crash unwinds
Test: through the jit data.
Change-Id: I6e7ee2f5bab2242028a06feece156dff21c0a974
2018-01-12 11:18:42 -08:00
Douglas Leung
61b1a1ae77 Add libunwindstack support for Mips and Mips64
This patch requires v3.18 kernel or above, because v3.10 kernel
has a bug (as of 8/1/2017) in the ptrace(GETREGSET) function for mips
and mips64.

Change-Id: I004c1fa190193eebe1c84440b366289122a6bd8a
Signed-off-by: Douglas Leung <douglas.leung@mips.com>
Signed-off-by: Dejan Jovicevic <dejan.jovicevic@mips.com>
2017-12-11 15:44:40 +01:00
Christopher Ferris
d06001d6e0 Split arch data into separate files.
Add an ArchEnum to express the arch of the Elf objects and Reg objects.

Split out the regs code into per arch pieces and generic parts.
Also, split out the header files for each arch.

Do not break out the test code yet, there isn't enough and it doesn't
help to maintain the tests.

Test: libunwindstack/libbacktrace/debuggerd unit tests pass.
Test: Running debuggerd -b <PIDS> yields valid data on bullhead.
Change-Id: If61f6c730c9ff2249f986b41de8c4d62f7158325
2017-12-06 16:01:40 -08:00
Christopher Ferris
ae3b136506 Use Unwinder object for unwind tool.
Test: Ran unwind on arm and arm64 processes.
Change-Id: I8a2a3ed31482044fe51d7e0d8c7f5588d5aad81c
2017-10-05 16:05:44 -07:00
Christopher Ferris
b9de87f7ed Add a new unwind method on error.
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
2017-09-22 16:55:12 -07:00
Christopher Ferris
5f118519fd Add a method to share the process memory object.
New function to create the process memory object. This allows for
a future where different remote process memory objects could be created
depending on the way remote memory can be created. Even different local
memory objects that access memory without doing any checks.

It also allows MemoryRange objects to share one single process memory object
and could help if the process memory object caches data.

Small changes to MapInfo::CreateMemory to when some errors are detected.
- Always check if the map is a device map, instead of only if the name
  is not empty.
- Check if a memory map is readable before creating the memory from process
  memory.

Bug: 23762183

Test: Ran unit tests, unwound on device using the new code.
Change-Id: I12a93c2dc19639689a528ec41c67bfac74d431b3
2017-09-05 14:30:22 -07:00
Josh Gao
0953ecd03a libunwindstack: make machine type a property of Regs.
There are no actual users of the machine type output parameter to
Regs::RemoteGet. The concrete implementations of Regs know what machine
type they represent anyway, so provide an accessor to query.

Test: treehugger
Test: libunwindstack tests on 32/64-bit host, hikey960
Change-Id: Ia25910531d36c41b2b6919f154cfa914aae63117
2017-08-25 14:48:09 -07:00
Christopher Ferris
d226a51409 Make the library usable as a library.
- Add namespace unwindstack everywhere so that it's easier for other
  code to use the library.
- Move some of the header files into include/unwindstack so that they
  can be exposed.
- Modify the headers so that only a limited number need to be exposed.
- Update the tools to use the new headers.
- Add a GetLoadBias() call on the Elf object. This prevents the need
  to get the interface object out of the Elf object.
- Move the GetRelPc() call out of the Reg class, to the Elf class. It's
  not always the case that a Reg object will be around when you want to
  get a relative pc. The tests for this moved to ElfTest.cpp.

Bug: 23762183

Test: Unit tests pass.
Change-Id: Iac609dac1dd90ed83d1a1e24ff2579c96c023bc3
2017-07-14 12:20:23 -07:00
Christopher Ferris
b5d7a87512 Move tools to separate directory.
Bug: 23762183

Test: Ran unit tests, ran new tools.
Change-Id: Icc7cbb4102a68042f4683d6dd622f21bc5e74deb
2017-07-13 13:20:10 -07:00