Commit graph

307 commits

Author SHA1 Message Date
Christopher Ferris
ce34d62351 Avoid signed extension of chars for build ids.
Added a unit test that fails before the change and passes afterwards.

Bug: 120606663

Test: All unit tests pass.
Change-Id: I054c7eac0c55abc3babe1d48a041f5819ad9db81
2019-01-30 12:09:11 -08:00
Christopher Ferris
f835ba6b66 Merge "Fix bug in unwind_info display of exidx frame." 2019-01-29 23:13:07 +00:00
Treehugger Robot
9f5e9978c2 Merge "Allow to move frames out of Unwinder." 2019-01-29 19:23:23 +00:00
Christopher Ferris
7010ecb50d Fix bug in unwind_info display of exidx frame.
The rosegment changed the load segments and broke the unwind_info printing
of unwind information for the arm exidx frame.

Test: Fixed and verified by dumping the arm exidx frame.
Change-Id: I7270175e4dcb7fee2b96a16d168880ebd09f19b1
2019-01-28 14:51:19 -08:00
Florian Mayer
1c993b76bf Allow to move frames out of Unwinder.
This saves a copy for every unwind we do in heapprofd.

Change-Id: Ife7aa1ce68831729d96ccd4c3e54ca531f98b6bc
2019-01-28 17:11:07 +00:00
Christopher Ferris
49047d711b Merge "Add GetPrintableBuildID()." 2019-01-26 07:03:35 +00:00
Christopher Ferris
ed7ca8bb14 Merge "Add a few leak check tests." 2019-01-26 06:45:39 +00:00
Christopher Ferris
b1c9c20eb2 Add GetPrintableBuildID().
The GetBuildID() function returns the raw build id data, so add a function
to get the printable hex version of the data.

Bug: 120606663

Test: New unit tests pass.
Change-Id: Ia5aefc97457efb08bbd30ea96cbb2d47ae59f954
2019-01-25 14:31:37 -08:00
Christopher Ferris
e1f7a63a4d Add a few leak check tests.
These tests are meant to replace the leak check tests from libbacktrace.

Bug: 120606663

Test: Ran tests on host and target.
Change-Id: I928b199304afc36b4bac78e9a2cd688b6f2910b9
2019-01-25 12:35:19 -08:00
Treehugger Robot
8306597e8f Merge "Fix crash in libunwindstack." 2019-01-25 04:29:30 +00:00
Florian Mayer
c479e4e789 Fix crash in libunwindstack.
Bug: 122657596

Test: New unit test that crashes without this change.
Change-Id: I5d978530a833345def94a58805d7ee93b23382bb
2019-01-24 16:29:36 -08:00
Vic Yang
cc8009ff04 libunwindstack: Move DwarfOp callback table to rodata section
There are currently two copies of DwarfOp callback tables in
data.rel.ro section, and that is 16KB of dirty memory per process on a
64-bit platform.

To reduce memory usage, we introduce a layer of indirection so that
all instances of DwarfOp can share a single callback table.  We also
get rid of the pointers for op names in the callback table so that the
entire table can be placed in rodata section.

Test result shows 1MB saving on cuttlefish, and 750KB saving on a Go
device (32-bit ARM).

Bug: 112073665
Test: Boot on cuttlefish and a Go device.
Change-Id: Idf90a513f37534ab1ef30d5742a9d3ea779f3661
2019-01-24 11:11:15 -08:00
Christopher Ferris
4aec66e810 Fix memory leak in UnwinderFromPid object.
Actually make the destructor virtual so that objects in
UnwinderFromPid get freed.

Also, explicitly make the DexFiles and JitDebug destructors virtual.

Bug: 123099840

Test: Ran UnwindTest.local_from_pid thousands of times.
Change-Id: I8bf11c0eb3587fa82f5f14f4723ea5c91da0fd46
2019-01-23 09:49:28 -08:00
Christopher Ferris
a5e0d695fa Merge "Fix flaky signal tests." 2019-01-23 17:39:09 +00:00
Florian Mayer
33d4bb3d88 Remove unused jit_debug unique_ptr.
Change-Id: I39ed4fdd5695fefff235b6c40d83d9780fc5b75b
2019-01-22 15:56:34 +00:00
Christopher Ferris
bc6a7e51e4 Fix flaky signal tests.
The signal tests that send a SIGUSR1 signal to a remote process, can
lead to a case where the code winds up in a location for which the
unwind information is not 100% accurate. This happens near the
end of the atomic functions which manipulate the stack right before
returning, but do not have separate cfi instructions for those last
few instructions.

Add a new test type for the from_context test that will wait explicitly
for the global g_finish and not piggy back on the remote test type.

Bug: 122902885

Test: Ran flaky tests 1000 times without failure on a taimen.
Change-Id: I7d0c9b016e3a3a2c0c0949cf74af11d7785a008c
2019-01-18 17:39:50 -08:00
Christopher Ferris
bf373edc3c Add caching of build id in MapInfo object.
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
2019-01-17 20:14:00 -08:00
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
cadacdf474 Fix usage of Read instead of ReadFully.
Found by inspection.

Test: Builds and unit tests passes.
Change-Id: I10b63534ae0a3bff9ce56e821c542fa69c15822d
2019-01-15 19:10:49 -08:00
Martin Stjernholm
2677b802bf Remove dependency on libdexfile internal header.
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
2019-01-11 21:05:50 +00:00
Martin Stjernholm
b49289b43a Some minor updates in the libdexfile external API.
Test: m
Test: mmma system/core/{libunwindstack,libbacktrace} and run host gtests
Bug: 119632407
Bug: 120978655
Change-Id: I919586ab503be3617e8a0604dfe48db331e7af94
2019-01-09 23:25:25 +00:00
Christopher Ferris
d76bd4c8d0 Merge "Remove CHECK in AdjustEncodedValue." 2019-01-08 16:47:06 +00:00
Treehugger Robot
a7d2ffa821 Merge "Move DwarfCfaInfo::kTable from data.rel.ro to rodata" 2018-12-21 12:58:26 +00:00
Christopher Ferris
a39aaf91eb Remove CHECK in AdjustEncodedValue.
The CHECK(encoding != DW_EH_PE_aligned) can trip given the right
arguments. This check isn't necessary, since the code will return
false in that case.

Add new unit test that tries all values to make sure no CHECK fires.

Bug: 120968571

Test: Passes new unit test, and passes fuzzing that failed before.
Change-Id: I062bcd18508c75cd3a4ca9dd12f922e25aafda8a
2018-12-20 08:40:58 -08:00
Martin Stjernholm
bb4f2b440a Revert^2 "Use libdexfile external API in libunwindstack."
This reverts commit cacf5bf6bc.

Reason for revert: Re-apply with proper fix for VNDK visibility on marlin and sailfish.

Test: Manual repro of http://b/121110092#comment1 on reported branch
Test: atest CtsRenderscriptTestCases
Test: mmma system/core/{libunwindstack,libbacktrace}, run host gtests
Test: Make image, flash, and reboot device.
Test: Forrest cts/art/gce-all: https://android-build.googleplex.com/builds/forrest/run/L00300000240828791
Test: Forrest cts/bionic/gce-all: https://android-build.googleplex.com/builds/forrest/run/L05600000240682947 (shows 27/2958 failed, but it doesn't pass on Blackbox either: http://screen/xbjioEf6UgR)
Test: Forrest cts/renderscript/gce-all: https://android-build.googleplex.com/builds/forrest/run/L66200000240680523
Bug: 119632407
Change-Id: I601aa97eac8127e30d753405f8bc1fc4ae7f849f
2018-12-19 21:04:35 +00:00
Treehugger Robot
1baa19b1a6 Merge "Fix offsets when shared lib split across maps." 2018-12-19 17:11:53 +00:00
Martin Stjernholm
cacf5bf6bc Revert "Use libdexfile external API in libunwindstack."
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
2018-12-19 00:11:04 +00:00
Christopher Ferris
a09c4a6ff2 Fix offsets when shared lib split across maps.
The linker was modified so that a shared library has a read-only
map, then a read-execute map to represent the whole shared library.
When backtraces are created, then the offsets are set incorrectly
for backtraces. For example, all backtraces wind up with an offset now,
and a shared library loaded out of an apk shows the wrong offset.

Changes:
- Fix the FormatFrame function which was putting the offset before the
  map name.
- Refactor the Maps and MapInfo classes to keep track of the previous map
  instead of all maps. This was the only map that was ever needed.
- Modify the unwind_for_offline tool to capture both the read-only and
  read-execute map when using the read-only segment option.

Bug: 120981155

Test: Updated unit tests pass.
Test: Unwinds on device don't show the offsets everywhere any more.
Change-Id: I75b3727221be9c20316dfdcd7a1c6d242d7ce948
2018-12-18 11:22:14 -08:00
Vic Yang
80aba5494a Move DwarfCfaInfo::kTable from data.rel.ro to rodata
Pages in .data.rel.ro are always dirty.  Move whatever we can to
.rodata so that we reduce memory pressure.

The size of rodata, text, and data.rel.ro  sections of linker64 on
cuttlefish before/after this change:
  rodata: 0x170e4 -> 0x17964 (+2176 bytes)
  text: 0xec919 -> 0xec919 (no change)
  data.rel.ro: 0x9cf0 -> 0x98f0 (-1024 bytes)

Test: Boot cuttlefish
Change-Id: Ib2fd2bb0afb50208d441731d8c31bc8f287272c3
2018-12-14 06:03:09 -08:00
Martin Stjernholm
1d6969ccb9 Merge "Use libdexfile external API in libunwindstack." 2018-12-14 13:36:30 +00:00
Christopher Ferris
065f156195 Do not remove speculative frames in all cases.
If the first frame of an unwind is a totally invalid pc that's not in
any map, a speculative frame is added. Rather than deleting this frame
if no more unwinding is possible, leave it. This fixes a case where
the only frame you get is an invalid one, but the speculative frame
winds up in a shared library or somewhere else and gets removed.

Bug: 120505086

Test: New unit tests to catch this case pass.
Test: Verified original crashing program now emits two backtrace lines.
Change-Id: I088dff21c057386dcdaeb3fc2578b24322683bd0
2018-12-13 10:41:08 -08:00
Martin Stjernholm
444e23d2fc Use libdexfile external API in libunwindstack.
Test: mmma system/core/{libunwindstack,libbacktrace}, run host gtests
Test: Make image, flash, and reboot device.
Bug: 119632407
Change-Id: I370f089a1b20ba432e136818b4325d46f99df708
2018-12-13 17:58:23 +00:00
Christopher Ferris
583ce2deff Merge "Fix handling of ro segments for embedded libs." 2018-12-13 03:18:58 +00:00
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
Chih-Hung Hsieh
1b7b7979af Fix performance-for-range-copy warnings
Bug: 30413223
Test: make with WITH_TIDY=1 DEFAULT_GLOBAL_TIDY_CHECKS=-*,performance*
Change-Id: I3ad102f2b0f971266d57488a3bd57d312f7ee3e6
2018-12-11 10:51:13 -08:00
Florian Mayer
3f1f2e07ab Add missing includes.
Test: Builds.
Change-Id: Ia8b79154902503cdd774dc3b4523466123b4324c
2018-12-06 10:09:20 -08:00
Florian Mayer
a5913bdd07 Merge "Read .note.gnu.build-id." 2018-12-06 10:57:26 +00:00
Florian Mayer
da459e56f7 Read .note.gnu.build-id.
This will be used by heapprofd to allow us to correlate build ids with
memory leaks in libraries and binaries.

Test: m
Test: host libunwindstack_test
Test: run unwind_info against my phone's libc.so (32/64) and compare
      to readelf Build ID output.

Bug: 120186412

Change-Id: I3cefd6cce9a8733509bf35b7175eb0f967783477
2018-12-05 14:13:30 +00:00
Christopher Ferris
ef6401091f Add support for caching small reads.
Add benchmarking to verify this is faster.

Test: Ran unit tests.
Change-Id: I1487114331f4581ec2368e56c4f18c6e3e6bcc7d
2018-11-28 13:04:58 -08:00
Christopher Ferris
5565906732 Remove overly restrictive check for memory.
Remove unit test that is not needed any more.

Slightly reorganize the code around the changed check.

Bug: 77958880

Test: Ran backtrace tests with new linker options.
Test: Ran libunwindstack unit tests.
Change-Id: Ie95707323fb51616a093cafb83e0343fa24e7e61
2018-11-15 14:06:26 -08:00
Mark Salyzyn
9f1cf25332 switch to using android-base/file.h instead of android-base/test_utils.h
Test: compile
Bug: 119313545
Change-Id: I4f7ad84743e974b4b4d1d7256088f6c8b749a237
2018-11-14 09:35:34 -08:00
Christopher Ferris
4568f4bc0f Verify that the elf matches the expected arch.
To avoid a case where a malicious app might try and trick the system to
create an elf and register object that mismatches, always verify that they
are the same arch.

Test: Ran unit tests.
Change-Id: I66978e9e02f8e4f396856912e7019528ead4838e
2018-10-29 18:08:09 -07:00
Treehugger Robot
551efd11f7 Merge "Fix off by one error." 2018-10-24 00:52:15 +00:00
Christopher Ferris
e8c4ecf49e Always init gnu_debugdata interface if it exists.
Every real call always sets the value to true to init the gnu_debugdata
interface, so remove this parameter.

Test: Builds, unit tests pass.
Change-Id: I07fb3adbbd5b65b51c0dc7608561e820a5095051
2018-10-23 12:13:54 -07:00
Florian Mayer
9c36a99ebc Fix off by one error.
Change-Id: I18a2d177f3212626b7091150f42dfe151e47570e
2018-10-23 18:10:41 +01:00
Christopher Ferris
56d0e07d70 Fix which maps to search for globals.
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
2018-10-17 14:23:10 -07:00
Christopher Ferris
6853a187e3 Merge "Fix up the definition of Elf::GetInfo." 2018-10-13 17:47:18 +00:00
Christopher Ferris
9d0ad238ca Fix problem adding too many frames.
When adding a frame with a dex pc, two frames will be added total. However,
if there is only enough room for a single frame, two get added any way.

Only add a single frame in this case, and add a unit test for this case.

Test: Passes unit tests.
Change-Id: If320584b126967a042c623d8fdf3f51dbc1c2251
2018-10-12 16:36:35 -07:00
Christopher Ferris
a2f38f1bde Fix up the definition of Elf::GetInfo.
The function should have returned a bool, so now it does.
Also use a different lighter weight function for validating the elf
in one place that didn't need to keep the max size value.

Test: Unit tests pass.
Change-Id: Ibde674e608091ba04abf22fad2fdc4dbdb2c6e73
2018-10-12 11:29:06 -07:00
Christopher Ferris
1f34c0e7a4 Fix handling of globals for new linker.
The new linker base map is read-only, but the global handling code
for jit and dex information assumed the base map was a read-execute
one. Relax that requirement to search read-only maps.

Adjust the unit tests for this case.

Bug: 117293117
Test: Passes unit tests.
Test: Passes art cfi tests with and without llvm linker.
Change-Id: I31a765d51847d0b8d778ace9cbaa29f42073f4d9
2018-10-08 19:47:33 -07:00
Christopher Ferris
9d5712c123 Implement support for linker rosegment option.
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
2018-10-03 20:48:45 -07:00
Christopher Ferris
3f9582f432 Fix implicit fall through switch cases.
Bug: 116020901

Test: Builds with -Werror=implicit-fallthrough.
Change-Id: I401f37585dae6cbf8995389a8a189abc2e102987
2018-09-19 14:12:59 -07:00
Chih-Hung Hsieh
502f4864d6 Suppress implicit-fallthrough warnings.
Add FALLTHROUGH_INTENDED for clang compiler.

Bug: 112564944
Test: build with global -Wimplicit-fallthrough.
Change-Id: I40f8bbf94e207c9dd90921e9b762ba51abab5777
2018-09-17 16:50:11 +00:00
Florian Mayer
ec004eb1b3 Merge "Allow to get raw register data on all platforms." 2018-08-08 21:37:46 +00:00
Mathieu Chartier
c2277fc216 Move to using ClassAccessor
In preparation for removal of ClassDataItemAccessor.

Bug: 79758018
Test: make
Test: test/run-test --host 137
Test: out/host/linux-x86/nativetest/libunwindstack_test/libunwindstack_test

Change-Id: I61a20fe7200a0d669b84573d3853b55877922602
2018-08-08 11:04:15 -07:00
Florian Mayer
932247e900 Allow to get raw register data on all platforms.
No new test failures introduced.

atest libunwindstack_test on aosp_walleye-userdebug:

Without patch:
Total: 800, Passed: 781, Failed: 19
With patch:
Total: 800, Passed: 781, Failed: 19

Change-Id: I8853c3e1594799761b481464b75e2904b38c4830
2018-08-08 11:19:41 +01:00
Christopher Ferris
5acf069a7a Be permissive about badly formed elf files.
Here is the allowable issues with an elf file that will not result in an error:
- The program headers/section headers offset points to unreadable memory.
- Allow missing program header and/or section headers.
- Allow a symbol table section header to point to invalid symbol table values.

There is no real reason to require the elf file be perfect. Everything in
the code has sane defaults, so any missing information won't cause any
problems.

This gets rid of the warning that occurs any time an elf is loaded
from memory. In memory elf files never contain all of the section headers,
and do not contain the symbol table data.

Update tests to test these new cases.

Test: Builds and unit tests all pass.
Change-Id: Iaefe2cd6b6c965a01ed425a112d6afae339f3b78
2018-08-03 22:02:05 +00:00
Christopher Ferris
2786608743 Fix incorrect left shifts.
Bug: 112142060

Test: New unit tests pass.
Change-Id: I0c47b22582f0bf75ab503364a337c7de4de3ec43
2018-08-02 18:01:02 -07:00
David Srbecky
02d0f7962d Create lookup table of DEX symbols.
Create fast lookup table instead of iterating every single time.
This will create the cache as methods are searched for.

Test: 137-cfi
Change-Id: I4be190bb1a637fef5d385b993be6a7e2203a6814
2018-07-20 10:48:59 -07:00
Christopher Ferris
5afddb0637 Remove Memory::ReadField.
In almost all cases, it is faster to read the entire structure rather
than do multiple reads using ReadField. The only case where it would be
slower is if doing a remote unwind and ptrace is the only way to read. In
all other cases, it's a single system call. In the ptrace call, it will be
multiple calls. Given that it is unusual to be forced to use ptrace,
it's better to avoid it.

It also reduces the code complexity to do a single read, and avoids
issues where the code forgets to read the field it needs.

Test: Unit tests pass on host and target.
Change-Id: I7b3875b2c85d0d88115b1776e1be28521dc0b932
2018-07-12 12:45:31 -07:00
Elliott Hughes
38488907a0 Move libbacktrace off cutils.
There's still <cutils/atomic.h> in a test, but I don't understand why
that isn't just std::atomic.

Also add a shared tgkill wrapper to libbase.

Bug: N/A
Test: ran tests
Change-Id: Idd4baa1e1670a84b3a8f35803cc5ffe5aae008a6
2018-07-11 13:55:07 -07:00
Christopher Ferris
92acaac8c7 Refactor the DwarfSection classes.
Modify the code for the no header sections because it turns out that
it is not okay to assume that the fdes are non-overlapping. It's necessary
to read the fdes in order and match as you go.

Modify the code so that it only reads until it finds the given pc rather than
reading all of the cie/fde entries at once.

Rewrote the tests to verify the new behavior.

Bug: 68998033
Bug: 110235461

Test: Ran libbacktrace/libunwindstack unit tests.
Test: Unwind the mediaserver process on a walleye and verify it
Test: unwinds properly.

Change-Id: I7bb59d1db72c13fa34caa9735ec34c1a60e20ed2
2018-06-27 14:52:21 -07:00
Christopher Ferris
f882a38864 Fix ARM program header values used for exidx.
Before, I was using p_vaddr to get the offset into the elf file where
the exidx frame starts. I changed that to use p_offset since this already
has the load bias offset in it and some elf files do not set p_vaddr
properly.

Also, use p_filesz instead of p_memsz, since again, some elf files do
not set p_memsz to the same as p_filesz.

Bug: 110704153

Test: All libbacktrace/libunwindstack unit tests pass.
Test: Randomly unwind process on a walleye.
Test: Verified that this properly dumps and unwinds the shared
Test: library that sets p_vaddr and p_memsz differently.
Change-Id: Ic7b1e5d07439f4636fa02cd884a8727a5737372b
2018-06-22 16:48:02 -07:00
Christopher Ferris
4cc36d2b43 Fix handling of load bias values.
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
2018-06-11 18:53:55 -07:00
Elliott Hughes
f6d7594d7f Try to fix LocalUnwinderTest.unwind_after_dlopen in APCT.
Failure:

  system/core/libunwindstack/tests/LocalUnwinderTest.cpp:181: Failure
  Value of: handle != nullptr
  Actual: false
  Expected: true

Bug: N/A
Test: N/A
Change-Id: I89b3228d51961f7bf952dd01f12f4ee61a97fe91
2018-06-06 10:48:41 -07:00
Treehugger Robot
6c9bb058c5 Merge "Build adbd for recovery" 2018-05-25 05:58:01 +00:00
Jiyong Park
a0e75045e6 Build adbd for recovery
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
2018-05-24 14:11:11 +09:00
Christopher Ferris
ca9a54b2c0 Add a specialized LocalUnwinder object.
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
2018-05-23 20:02:30 -07:00
Treehugger Robot
2ed14f3923 Merge "Libunwindstack: Add -O0 to tools defaults on host" 2018-05-23 19:37:01 +00:00
Christopher Ferris
5e516cad93 Fix error messages handling.
Test: Builds.
Change-Id: I083ee4a51047e97e2ead78f40c82a21198f2b361
2018-05-21 13:26:58 -07:00
Andreas Gampe
8ccbe4258e Libunwindstack: Add -O0 to tools defaults on host
Extend the debug support from the host library to host tools.

Test: mmma system/core/libunwindstack
Change-Id: Ib6ea5f021d6b8139c545eaa2e6b1675befa4d3bd
2018-05-21 08:24:20 -07:00
Christopher Ferris
239425b9fa Fix bug when doing signal handler lookup.
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
2018-05-17 18:58:42 -07:00
Yabin Cui
3841accba8 libprocinfo: add functions reading process map file.
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
2018-05-14 14:00:18 -07:00
Sen Jiang
2ef03e0f01 Match LZMA SDK 18.05 API.
Test: libunwindstack_test
Change-Id: Ie1c9c91fb4f3585a7543df55a71abf64f8fc6dff
2018-05-04 13:12:36 -07:00
Elliott Hughes
40fdf3f4ab Add test_suites lines.
Bug: N/A
Test: builds
Change-Id: Ic5e2b9206bcfcb53c774989013b5db6aab462e42
2018-04-27 16:12:06 -07:00
Josh Gao
2f37a15472 libunwindstack: add Regs::Clone.
Add a way to copy a Regs object.

Bug: http://b/77296294
Test: libunwindstack_test
Change-Id: I28aff510aa3e1b677d5ae46dc3bfe7652817ce52
2018-04-20 13:23:20 -07:00
Christopher Ferris
6633b0ca09 Add a MemoryOfflineBuffer object.
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
2018-04-03 18:37:52 -07:00
Christopher Ferris
95a524460a Merge "Cache DWARF location rules for a given pc." 2018-03-29 14:47:35 +00:00
David Srbecky
3386ebade2 Cache DWARF location rules for a given pc.
Decoding the DWARF opcodes is expensive so make sure we cache it.

This speeds unwinding in simpleperf by over a factor of 3x.

Add unit tests for this new behavior.

Bug: 77258731

Test: libbacktrace/libunwindstack unit tests on host and target.
Test: Ran debuggerd -b on various processes on target.
Change-Id: Ia516c0fa5d3e5f76746190bb4b6fdf49fd1c9388
2018-03-29 14:47:13 +00:00
Christopher Ferris
6dbc28ece3 Fix null pointer dereference in RegsArm.
Fix RegsArm::GetPcAdjustment to check for an invalid elf before trying
to read memory.
Modify the tests for this so it crashes without this change.

Also modify the GetPcAdjustment for all different architectures so
that unless the relative pc is too small, it will return the minimum
amount that should be adjusted. This is to handle cases where we still
want to adjust the pc but it's in an invalid elf. Mostly this is for
handling cases when the pc is in jit gdb debug code so that we use the
right unwind information.

Bug: 77233204

Test: Passes unit tests for libbacktrace/libunwindstack.
Change-Id: Id73609adaf3b80a583584441de228156fec3afa7
2018-03-28 17:21:01 -07:00
Yabin Cui
d5b22c5f04 Support a map that represents gdb jit elf data.
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
2018-03-21 17:23:54 -07:00
Christopher Ferris
b22451f178 Merge "Always set the sp reg to the cfa for DWARF." 2018-03-19 17:48:59 +00:00
David Srbecky
e8d1b75c0c Merge "Don't include map name if the consumer doesn't want names." 2018-03-19 11:23:10 +00:00
David Srbecky
e62f4c4d4c Don't include map name if the consumer doesn't want names.
Simpleperf doesn't need the name, so avoid the string copies.

This seems to speed up simpleperf by around 20%.

Test: backtrace_test libunwindstack_test
Change-Id: Iba064c7078f7e5ecfc9d8539ba09c14495a52158
2018-03-19 11:20:00 +00:00
Yabin Cui
11e96fe48a Always set the sp reg to the cfa for DWARF.
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
2018-03-16 23:38:07 -07:00
Christopher Ferris
704ec9adba Handle ARM thumb function symbols.
ARM thumb functions will have the zero bit set to one, which can cause
function name lookups to fail.

Add an ARM special GetFunctionName that handles this condition.

Fix a couple of the function offsets in unit tests.

Bug: 74844137

Test: Ran unit tests.
Test: Ran debuggerd -b on processes on a bullhead device.
Change-Id: Ibd407db34eaaa641f91fdb4f589c44a0dcc0216a
2018-03-15 15:14:18 -07:00
David Srbecky
ff9b1db67c Merge "Remove libunwindstack_dex" 2018-03-13 11:31:22 +00:00
David Srbecky
18121dc4d0 Remove libunwindstack_dex
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
2018-03-12 20:13:21 +00:00
David Srbecky
3692f25199 Don't implicitly dereference DW_CFA_def_cfa_expression.
The specification isn't entirely clear. Follow the gdb interpretation.

Bug: 73954823
Test: libunwindstack_test
Change-Id: If72717f54eed84e442f43af19e615143a9796b68
2018-03-08 14:44:11 -08:00
Christopher Ferris
81744ac69f Remove leftover commented out code.
Test: Compiles.
Change-Id: Icf1cf1640e76450d5327395eb94dbd87d2faac36
2018-03-06 11:24:55 -08:00
David Srbecky
8fbdbba9f5 Merge "Adjust DEX file reading to follow layout changes in ART." 2018-02-23 17:53:23 +00:00
Christopher Ferris
a2ec50bf57 Change the GetAdjustedRelPc to GetPcAdjustment.
This cleans up a bit of the Unwinder code to make it clear what's
going on.

Modify the offline unit tests to verify the pc and sp to make sure
that those values get computed correctly.

Test: Passes unit tests.
Test: Passes 137-cfi art tests.
Change-Id: I0787a1d77b8726d3defd08f31c7476f6798f8d0d
2018-02-21 20:16:39 -08:00
Christopher Ferris
e4b3a6aaa4 Add ability to skip function name resolution.
Bug: 73558129

Test: New unit tests pass.
Change-Id: I3a6b17d2590aacb367ab3e3a51cc85be73ad64eb
2018-02-20 17:10:23 -08:00
Treehugger Robot
0609e8d231 Merge "bpfmt." 2018-02-20 02:02:59 +00:00
Elliott Hughes
dc699a269f bpfmt.
Bug: N/A
Test: builds
Change-Id: I89ad00e1c4c7e0767bc80a7ac7935a4d55e090ac
2018-02-16 17:58:14 -08:00
Christopher Ferris
d9575b668b Modify elf cache to handle elf_offsets properly.
Bug: 73498823

Test: All unit tests pass.
Test: Simpleperf run that previously failed, passes now.
Change-Id: Iff3a1f2f641a46ab9a0326579af3649f0c76fc65
2018-02-16 14:52:38 -08:00
David Srbecky
4015ef411a Adjust DEX file reading to follow layout changes in ART.
I have changed the root DEX debug descriptor in ART to more
closely follow the JIT debug descriptor. Add the appropriate
offsets to correctly fetch the linked list head for DEX files.

Test: testrunner.py -t 137
Test: libunwindstack_test
Change-Id: I90402befc88fec42658f7330d51ee79756a7f872
2018-02-16 14:54:49 +00:00
Christopher Ferris
beae42bc7f Fix soname reading code.
The dynamic section contained an address, not an offset into the elf
file to indicate where the soname exists. Changed to use the strtab
entries in the section headers to map this address to the actual offset.

Refactor the soname test a bit to make it easier to verify the code.

Bug: 73499044

Test: Passes new unit tests.
Test: Ran unwind_info on the failing shared elf and verified the soinfo
Test: is correct.
Change-Id: I16ba148389bcb9aadd3566fb442dac27f89fe894
2018-02-15 17:57:13 -08:00
David Sehr
3a26c27252 Move libdexfile out of runtime
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
2018-02-14 17:42:59 +00:00
Christopher Ferris
559c7f2092 Implement new DEX PC lookup scheme.
GDB wasn't handling the old one gracefully.

- Create a RegsInfo structure that can be used to properly eval expression
  data.
- Remove the versions on Dwarf ops. It doesn't work the in the real world
  and doesn't add useful information.
- Fix dex pc frame number bug.

Test: testrunner.py -j40 --host --cdex-fast -t 137
Test: libunwindstack_test
Test: All unit tests pass.
Change-Id: Iac4fea651b81cb6087fd237a9a5027a352a49245
2018-02-13 16:45:38 -08:00
Christopher Ferris
e4df5f5ab5 Fix computation of pc.
Fix the case where a non-zero load bias or a non-zero elf offset causes
the pc to be set incorrectly.

Add unit tests for these cases.

Bug: 73172903

Test: Ran unit tests.
Test: Ran the unit tests from the simpleperf CL that detected the failure.
Change-Id: Id8802c00b34c66875edd4926a20c5fccd2bb7d72
2018-02-12 14:06:13 -08:00
Christopher Ferris
73a2508dc4 Merge "Fix off by 4 error handling eh_frame hdr." 2018-02-12 18:58:34 +00:00
Christopher Ferris
a8c397317d Clear dex pc to avoid duplicate frames.
Bug: 73228466

Test: Passes new unit tests, fails without change.
Change-Id: I3660bfd16cbf2d5cf96490ca7714bc5f97914884
2018-02-12 08:46:19 -08:00
Christopher Ferris
e37e2d05b1 Fix off by 4 error handling eh_frame hdr.
- 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
2018-02-10 17:11:23 -08:00
Christopher Ferris
53914165e4 Expose per arch headers.
Bug: 73013352

Test: Compiles.
Change-Id: Ic05660db7d7858a9857143ee5e58cdaddcf52a35
2018-02-08 19:29:08 -08:00
David Sehr
892e675a89 Remove dependency on -no_art variant
Remove an external dependency on a shim I used to protect against
renaming.

Bug: 22322814
Test: make -j 50
Change-Id: I7e6eaee7d82a1a42d4c37daa74803cefc7bb68ce
2018-02-07 15:19:22 -08:00
Christopher Ferris
e762f1f193 Check that dex pc is in a valid map.
Add new unit tests for dex pc being non-zero.

Bug: 73004673

Test: Ran unit tests.
Test: Ran art 137-cfi test on host for interpreter.
Change-Id: I09bbf96d0ed65fc1e5896e4ab2bc67867e3b7fdb
2018-02-06 15:00:04 -08:00
David Srbecky
d663ef9772 Merge "Fix in-memory loading of cdex files with shared data." 2018-02-06 11:00:31 +00:00
Christopher Ferris
5f5cb238f0 Small test clean up.
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
2018-02-05 13:12:54 -08:00
David Srbecky
417f7c3720 Fix in-memory loading of cdex files with shared data.
Several cdex files may share the same data for de-duplication.

Bug: 72520014
Test: Disable DexFileFromFile and then run ART's 137 test.
Change-Id: Icfe04255cc20a302f844c2e3e3016578856e1f82
2018-02-05 20:40:31 +00:00
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
David Srbecky
f9006ec9b6 Fix symbol resolution within a dex file.
Fixes the ART 137-cfi test, currently failing on buildbot.

Test: testrunner.py -j40 --host --cdex-none -t 137 -b
Change-Id: I16a007b291702207bbd003fd1e78e8e5ced7cd68
2018-02-01 14:51:57 +00:00
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
bb4d172f70 Merge "Add a global elf cache." 2018-01-26 14:55:15 +00:00
Christopher Ferris
0b79ae155f Add a global elf cache.
Bug: 65682279

Test: Ran new unit tests.
Change-Id: I19c64614b2b11a27f58204d4cc34913c02e04c36
2018-01-25 17:11:33 -08:00
Christopher Ferris
c85935de54 Remove DwarfError.h that moved.
I think a rebase recreated this file, so deleting this now.

Bug: 65682279

Test: Compiles.
Change-Id: I1f885ed6254089ef50f293b4c407b110f8c878da
2018-01-25 16:02:20 -08:00
Treehugger Robot
dc0edb586d Merge "Fix wrong mov instruction size." 2018-01-25 23:34:56 +00:00
Chih-Hung Hsieh
09f88076c8 Fix wrong mov instruction size.
* New clang 7.0 assembler rejects mov with wrong length.

Bug: 72412103
Test: build and boot in emulator
Change-Id: If1a1affaa4a149265f8cc2b8bf463e58e71cc47a
2018-01-25 11:44:19 -08:00
Christopher Ferris
2fcf4cf13e Add error propagation into Unwinder/Elf objects.
The backtrace offline code uses these error codes to diagnose errors.
In addtion, I've had cases where seeing these errors would help diagnose
failures.

This also allows us to add a few features to indicate why an unwind
terminated (such as max frames exceeded).

Bug: 65682279

Test: Updated unit tests pass.
Change-Id: If82b5092698e8a194016d670efff1320f9b44d50
2018-01-24 17:50:46 -08:00
Christopher Ferris
1a141a0925 Small behavioral changes to the unwinder.
- 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
2018-01-24 13:20:03 -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
ed37aca987 Find first non-zero jit debug entry.
Sometimes a process will have multiple shared libraries loaded
that have defined __jit_debug_descriptor. Specifically, art testing
will load libart.so and libartd.so, which would have broken unwinding
through jit'd code for art testing if libart.so winds up being found first.
In order to avoid duplicating the code for the linker to figure out
which one is live, change the algorithm to find the first non-zero
first_entry_ set in __jit_debug_descriptor.

Bug: 68396769

Test: Passes unit tests.
Test: Verified this can unwind 137-cfi on arm/arm64.
Change-Id: Ic4d403065d2c6f22476ef0171e7add17cd1464cd
2018-01-16 14:59:51 -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
Christopher Ferris
3dfd2aea7a Add tool to save information from a process.
Also, modify the ProcessVmRead function to allow arbitrarily large
reads and add a test for it.

Test: Run tool and verify the output can be used to do an offline
Test: unwind.
Test: Ran unit tests.
Change-Id: I0974ddca4f5cf72b4c9fa29b597a0a669e223828
2017-12-20 12:57:01 -08:00
Treehugger Robot
8b18000b39 Merge "unwindstack: add some perfunctory MemoryOffline tests." 2017-12-18 22:21:45 +00:00
Josh Gao
f4a94c44b6 unwindstack: add some perfunctory MemoryOffline tests.
Add some tests for the behavior of MemoryOffline.

Test: libunwindstack_test 32/64 on hikey960
Change-Id: Ib65a0fe5347b86062ffeaf0adaf9af57066edb76
2017-12-15 14:11:12 -08:00
Christopher Ferris
e7b6624c3f Fix issues in libunwindstack.
- Add a load_bias field in MapInfo so that it can be loaded offline,
  and also so it can be cached.
- Add an Add function to the Maps class so that it's possible to manually
  create a map.
- Remove the OfflineMaps class since I haven't found a reason for this to
  exist.
- Add a pointer to the gnu debugdata compressed section in the interface
  itself and modify the step path to try eh_frame, then debug_frame, then
  gnu_debugdata. This way arm can add exidx as the last step behind
  gnu_debugdata. Add an offline test to verify the order of unwind.
- Fix x86_64_ucontext_t since it was a different size on 32 bit and 64 bit
  systems.

Test: Pass new unit tests.
Change-Id: I978b70d6c244bd307c62a29886d24c1a8cb2af23
2017-12-15 11:17:45 -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
02fdb569f6 Do not check arch for format check.
Use a generic check if the address is 32 bits when using the default
formating of a backtrace line instead of an arch check.

Test: New unit tests pass.
Change-Id: Id609abc037d7b437a02d52763aa91fbefe5f4d5b
2017-12-08 15:44:14 -08:00
Christopher Ferris
70f7d47f3c Merge "Add method to detect remote read function to use." 2017-12-08 20:09:34 +00:00
Christopher Ferris
e328673a30 Add method to detect remote read function to use.
The process_vm_read function is much faster than ptrace, but sometimes
that will not work on a remote process. Modify the libunwindstack
MemoryRemote object to figure out which one it can use.

Wrote new unit test to verify this checking behavior.

Modify libbacktrace so that the read from libunwind is used instead of
using the default ptrace calls.

Add some benchmarks to libbacktrace to compare the two different methods.

Test: Ran unit tests libbacktrace/libunwindstack/debuggerd.
Test: Ran debuggerd -b <SYSTEM_SERVER_PID>
Test: Ran debuggerd -b <MEDIACODEC PID>
Test: Ran debuggerd -b <RANDOM_PID>
Test: Used crasher to create tombstones and verified stack data is
Test: dumped properly.
Change-Id: If75ca238289532dd8e1de430d569cabb2523380a
2017-12-07 19:00:00 -08:00
Elliott Hughes
3289b9c928 Merge "Add OWNERS." 2017-12-07 23:21:26 +00:00
Elliott Hughes
693d63f9cf Add OWNERS.
Bug: N/A
Test: N/A
Change-Id: Ie785058c0f5eb9b4086c98ccba6e63e3ed411b65
2017-12-07 13:30:03 -08:00
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
b7de5f5429 Demand read load bias for a map.
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
2017-12-05 13:12:47 -08:00
Christopher Ferris
e714ed2774 Switch MemoryRemote to use ptrace.
Some processes will fail to read when using process_vm_read, so switch
back to ptrace for now. For example, the system_server process only
gets two frames without this fix.

Fix up some of the remote memory read unit tests to allow passing
even when using ptrace.

Bug: 70160908

Test: All unit tests pass, debuggerd -b <system_server pid> works.
Change-Id: I37c67bf9c480d7268c9fe32dad6a8d78a4020b85
2017-12-04 14:27:34 -08:00
Treehugger Robot
b4fda18d83 Merge changes I53c2c560,I7d845ac5,I8b11d923
* changes:
  unwindstack: rename Memory::ReadPartially to Read.
  unwindstack: rename Memory::Read to ReadFully.
  unwindstack: add Memory::ReadPartially.
2017-12-02 00:12:21 +00:00
Christopher Ferris
c3d79f7c07 Fix incorrect usage of relative pcs.
When stepping, it's necessary to use both the unaltered relative pc
and the adjusted relative pc. If the adjusted pc is not used, the
wrong unwind information can be used.

Added new offline unit tests that take real data and verifies that it
unwinds properly.

Fix a bug in the map code that would not properly parse map data for
a 64 bit process when done in a 32 bit process.

Fix bug in eh_frame processing that didn't adjust the pc correctly.
Fix unit tests related to the pc adjustment.

Bug: 69475565

Test: Passes libbacktrace/libunwindstack unit tests.
Test: Run debuggerd -b on processes on a hikey.
Change-Id: Ic501a1c4549c5f61d2742a7105c42a960f2c892b
2017-11-29 16:10:08 -08:00
Christopher Ferris
f819c1d94b Merge "Allow multiple threads sharing a map to unwind." 2017-11-29 02:58:06 +00:00
Christopher Ferris
be788d891d Allow multiple threads sharing a map to unwind.
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
2017-11-28 15:20:38 -08:00
Christopher Ferris
a141709b21 Add way to specify an offset in an elf file.
This is to support the ability to dump an elf embedded in an apk.

Test: Ran unwind_info on a file, then ran it on an apk with an offset.
Change-Id: I8f23f4bdaadfd3665900bdd45d50cb270e2e0eed
2017-11-28 10:59:33 -08:00
Josh Gao
b837763b49 unwindstack: rename Memory::ReadPartially to Read.
Test: mma
Test: treehugger
Change-Id: I53c2c5600fb44620b629c01db85a67789594595f
2017-11-15 15:38:13 -08:00
Josh Gao
ef35aa5d40 unwindstack: rename Memory::Read to ReadFully.
Rename Memory::Read to ReadFully to match its semantics with that of
android::base. ReadPartially will be renamed to Read in a follow up
commit, kept intentionally separate so that there aren't any callers
accidentally switched from ReadFully to Read.

Test: treehugger
Change-Id: I7d845ac5244c3025d92c8512e960e5d0d1da05af
2017-11-15 15:38:13 -08:00
Josh Gao
29c5378e91 unwindstack: add Memory::ReadPartially.
Add a way to read while allowing for partial reads.

Test: new tests added to libunwindstack_test, ran 32/64 on hikey960, sailfish
Test: ran unwind on hikey960/sailfish
Change-Id: I8b11d9230fcd3122148ef3f980863ac1404ad70a
2017-11-15 15:38:13 -08:00
Christopher Ferris
d96cbae4d4 Fix another nullptr dereference.
In this case, if the .eh_frame_hdr doesn't exist, we would crash.

Bug: 68813077

Test: Pass new unit tests, verified that without the fix, the unit test
Test: would crash.
Change-Id: I4f1365a76fe5c2fb69fa106a1ef15889c14e7611
2017-11-08 11:04:48 -08:00
Christopher Ferris
c9dee84d81 Add support for only a .eh_frame.
Static executables only have a .eh_frame section and no .eh_frame_hdr
section. Add support for this by rearranging the class hierarchy and
creating a DwarfEhFrameWithHdr class and a DwarfEhFrame class to handle
the different cases.

Add new unit tests for DwarfEhFrame and for the new functionality.

Bug: 68820189

Test: Passes new unit tests, unwinds static executables.
Change-Id: I63d7cb8c52a686e96579a2266e18c0d06bbb6e63
2017-11-07 13:22:39 -08:00
Christopher Ferris
13b86658b9 Fix nullptr dereference.
If an entry is found in .eh_frame_hdr, but it's not properly in .eh_frame,
then the code would crash. The assumption that the header always points
to valid fde data is not guaranteed.

Bug: 68813077

Test: Passes new unit test that crashed before the change.
Change-Id: I914d9bda0d442cd232e2a056ae490301a8850105
2017-11-05 14:01:43 -08:00
Christopher Ferris
fda7edd13e Move sp/pc not changing check into Unwinder.
Remove this check from the DwarfSection class.

Rather than have every step function make the check, doing it at the
top level avoids having every function do the same check.

Bug: 68167269

Test: New unit tests, ran debuggerd -b on processes.
Change-Id: I23b7c799faaf26c93c1b72848df18c78de6c42fb
2017-10-31 17:51:02 -07:00
Josh Gao
e22701ee8a libbacktrace: remove exit time destructors.
If libbacktrace is statically linked into a library that interposes
libc, exit-time destructors can lead to a segfault upon exit if static
variables are used after their destruction.

Remove the one use of a static variable (with inconsequential
performance impact of less than 1us per backtrace), and enable
-Wexit-time-destructors to ensure this stays fixed in the future.

Test: mma
Change-Id: Icdaf1cf1c1f166cf501d9ecd1983c44e4305f7e9
2017-10-26 14:20:17 -07:00
Christopher Ferris
1cb84cea2f Add an interface for stopping in certain maps.
Also, change the std::set parameters to std::vector. As jmgao points out,
a small std::set is not really the best choice for performance reasons.

Test: All unit tests pass, enabled the new unwinder and did a kill -3 on
Test: an android process.
Change-Id: I81227d7b79a9b7cf1d54fb0e3331d3cf4d4d3c4f
2017-10-24 15:45:59 -07:00