Merge "Compare new unwinder to old unwinder in debuggerd." (1f6a4814) · Commits · e / os / android_system_core

debuggerd/Android.bp

+2 −0

Original line number	Diff line number	Diff line
		@@ -106,6 +106,7 @@ cc_library_static {
		"libdebuggerd",
		"libbacktrace",
		"libunwind",
		"libunwindstack",
		"liblzma",
		"libcutils",
		],
		@@ -171,6 +172,7 @@ cc_library_static {
		static_libs: [
		"libbacktrace",
		"libunwind",
		"libunwindstack",
		"liblzma",
		"libbase",
		"libcutils",

debuggerd/crash_dump.cpp

+8 −2

Original line number	Diff line number	Diff line
		@@ -329,6 +329,11 @@ int main(int argc, char** argv) {
		LOG(FATAL) << "failed to create backtrace map";
		}
		}
		std::unique_ptr<BacktraceMap> backtrace_map_new;
		backtrace_map_new.reset(BacktraceMap::CreateNew(main_tid));
		if (!backtrace_map_new) {
		LOG(FATAL) << "failed to create backtrace map new";
		}

		// Collect the list of open files.
		OpenFilesList open_files;
		@@ -408,8 +413,9 @@ int main(int argc, char** argv) {
		dump_backtrace(output_fd.get(), backtrace_map.get(), target, main_tid, process_name, threads, 0);
		} else {
		ATRACE_NAME("engrave_tombstone");
		engrave_tombstone(output_fd.get(), backtrace_map.get(), &open_files, target, main_tid,
		process_name, threads, abort_address, fatal_signal ? &amfd_data : nullptr);
		engrave_tombstone(output_fd.get(), backtrace_map.get(), backtrace_map_new.get(), &open_files,
		target, main_tid, process_name, threads, abort_address,
		fatal_signal ? &amfd_data : nullptr);
		}

		// We don't actually need to PTRACE_DETACH, as long as our tracees aren't in

debuggerd/libdebuggerd/include/tombstone.h

+4 −4

Original line number	Diff line number	Diff line
		@@ -35,10 +35,10 @@ class BacktraceMap;
		int open_tombstone(std::string* path);

		/* Creates a tombstone file and writes the crash dump to it. */
		void engrave_tombstone(int tombstone_fd, BacktraceMap* map, const OpenFilesList* open_files,
		pid_t pid, pid_t tid, const std::string& process_name,
		const std::map<pid_t, std::string>& threads, uintptr_t abort_msg_address,
		std::string* amfd_data);
		void engrave_tombstone(int tombstone_fd, BacktraceMap* map, BacktraceMap* map_new,
		const OpenFilesList* open_files, pid_t pid, pid_t tid,
		const std::string& process_name, const std::map<pid_t, std::string>& threads,
		uintptr_t abort_msg_address, std::string* amfd_data);

		void engrave_tombstone_ucontext(int tombstone_fd, uintptr_t abort_msg_address, siginfo_t* siginfo,
		ucontext_t* ucontext);

debuggerd/libdebuggerd/tombstone.cpp

+84 −12

Original line number	Diff line number	Diff line
		@@ -495,8 +495,55 @@ __attribute__((weak)) void dump_registers(log_t* log, const ucontext_t*) {
		_LOG(log, logtype::REGISTERS, " register dumping unimplemented on this architecture");
		}

		static void dump_thread(log_t* log, pid_t pid, pid_t tid, const std::string& process_name,
		const std::string& thread_name, BacktraceMap* map,
		static bool verify_backtraces_equal(Backtrace* back1, Backtrace* back2) {
		if (back1->NumFrames() != back2->NumFrames()) {
		return false;
		}
		std::string back1_str;
		std::string back2_str;
		for (size_t i = 0; i < back1->NumFrames(); i++) {
		back1_str += back1->FormatFrameData(i);
		back2_str += back2->FormatFrameData(i);
		}
		return back1_str == back2_str;
		}

		static void log_mismatch_data(log_t* log, Backtrace* backtrace) {
		_LOG(log, logtype::THREAD, "MISMATCH: This unwind is different.\n");
		if (backtrace->NumFrames() == 0) {
		_LOG(log, logtype::THREAD, "MISMATCH: No frames in new backtrace.\n");
		return;
		}
		_LOG(log, logtype::THREAD, "MISMATCH: Backtrace from new unwinder.\n");
		for (size_t i = 0; i < backtrace->NumFrames(); i++) {
		_LOG(log, logtype::THREAD, "MISMATCH: %s\n", backtrace->FormatFrameData(i).c_str());
		}

		// Get the stack trace up to 8192 bytes.
		std::vector<uint64_t> buffer(8192 / sizeof(uint64_t));
		size_t bytes =
		backtrace->Read(backtrace->GetFrame(0)->sp, reinterpret_cast<uint8_t*>(buffer.data()),
		buffer.size() * sizeof(uint64_t));
		std::string log_data;
		for (size_t i = 0; i < bytes / sizeof(uint64_t); i++) {
		if ((i % 4) == 0) {
		if (!log_data.empty()) {
		_LOG(log, logtype::THREAD, "MISMATCH: stack_data%s\n", log_data.c_str());
		log_data = "";
		}
		}
		log_data += android::base::StringPrintf(" 0x%016" PRIx64, buffer[i]);
		}

		if (!log_data.empty()) {
		_LOG(log, logtype::THREAD, "MISMATCH: data%s\n", log_data.c_str());
		}

		// If there is any leftover (bytes % sizeof(uint64_t) != 0, ignore it for now.
		}

		static bool dump_thread(log_t* log, pid_t pid, pid_t tid, const std::string& process_name,
		const std::string& thread_name, BacktraceMap* map, BacktraceMap* map_new,
		uintptr_t abort_msg_address, bool primary_thread) {
		log->current_tid = tid;
		if (!primary_thread) {
		@@ -510,7 +557,18 @@ static void dump_thread(log_t* log, pid_t pid, pid_t tid, const std::string& pro
		dump_abort_message(backtrace.get(), log, abort_msg_address);
		}
		dump_registers(log, tid);
		bool matches = true;
		if (backtrace->Unwind(0)) {
		// Use the new method and verify it is the same as old.
		std::unique_ptr<Backtrace> backtrace_new(Backtrace::CreateNew(pid, tid, map_new));
		if (!backtrace_new->Unwind(0)) {
		_LOG(log, logtype::THREAD, "Failed to unwind with new unwinder: %s\n",
		backtrace_new->GetErrorString(backtrace_new->GetError()).c_str());
		matches = false;
		} else if (!verify_backtraces_equal(backtrace.get(), backtrace_new.get())) {
		log_mismatch_data(log, backtrace_new.get());
		matches = false;
		}
		dump_backtrace_and_stack(backtrace.get(), log);
		} else {
		ALOGE("Unwind failed: pid = %d, tid = %d", pid, tid);
		@@ -524,6 +582,8 @@ static void dump_thread(log_t* log, pid_t pid, pid_t tid, const std::string& pro
		}

		log->current_tid = log->crashed_tid;

		return matches;
		}

		// Reads the contents of the specified log device, filters out the entries
		@@ -657,9 +717,10 @@ static void dump_logs(log_t* log, pid_t pid, unsigned int tail) {
		}

		// Dumps all information about the specified pid to the tombstone.
		static void dump_crash(log_t* log, BacktraceMap* map, const OpenFilesList* open_files, pid_t pid,
		pid_t tid, const std::string& process_name,
		const std::map<pid_t, std::string>& threads, uintptr_t abort_msg_address) {
		static void dump_crash(log_t* log, BacktraceMap* map, BacktraceMap* map_new,
		const OpenFilesList* open_files, pid_t pid, pid_t tid,
		const std::string& process_name, const std::map<pid_t, std::string>& threads,
		uintptr_t abort_msg_address) {
		// don't copy log messages to tombstone unless this is a dev device
		char value[PROPERTY_VALUE_MAX];
		property_get("ro.debuggable", value, "0");
		@@ -668,7 +729,8 @@ static void dump_crash(log_t* log, BacktraceMap* map, const OpenFilesList* open_
		_LOG(log, logtype::HEADER,
		"* * * * * * * * * * * * * * * *\n");
		dump_header_info(log);
		dump_thread(log, pid, tid, process_name, threads.find(tid)->second, map, abort_msg_address, true);
		bool new_unwind_matches = dump_thread(log, pid, tid, process_name, threads.find(tid)->second, map,
		map_new, abort_msg_address, true);
		if (want_logs) {
		dump_logs(log, pid, 5);
		}
		@@ -678,7 +740,9 @@ static void dump_crash(log_t* log, BacktraceMap* map, const OpenFilesList* open_
		const std::string& thread_name = it.second;

		if (thread_tid != tid) {
		dump_thread(log, pid, thread_tid, process_name, thread_name, map, 0, false);
		bool match =
		dump_thread(log, pid, thread_tid, process_name, thread_name, map, map_new, 0, false);
		new_unwind_matches = new_unwind_matches && match;
		}
		}

		@@ -690,6 +754,14 @@ static void dump_crash(log_t* log, BacktraceMap* map, const OpenFilesList* open_
		if (want_logs) {
		dump_logs(log, pid, 0);
		}
		if (!new_unwind_matches) {
		_LOG(log, logtype::THREAD, "MISMATCH: New and old unwinder do not agree.\n");
		_LOG(log, logtype::THREAD, "MISMATCH: If you see this please file a bug in:\n");
		_LOG(log, logtype::THREAD,
		"MISMATCH: Android > Android OS & Apps > Runtime > native > tools "
		"(debuggerd/gdb/init/simpleperf/strace/valgrind)\n");
		_LOG(log, logtype::THREAD, "MISMATCH: and attach this tombstone.\n");
		}
		}

		// open_tombstone - find an available tombstone slot, if any, of the
		@@ -745,16 +817,16 @@ int open_tombstone(std::string* out_path) {
		return fd;
		}

		void engrave_tombstone(int tombstone_fd, BacktraceMap* map, const OpenFilesList* open_files,
		pid_t pid, pid_t tid, const std::string& process_name,
		const std::map<pid_t, std::string>& threads, uintptr_t abort_msg_address,
		std::string* amfd_data) {
		void engrave_tombstone(int tombstone_fd, BacktraceMap* map, BacktraceMap* map_new,
		const OpenFilesList* open_files, pid_t pid, pid_t tid,
		const std::string& process_name, const std::map<pid_t, std::string>& threads,
		uintptr_t abort_msg_address, std::string* amfd_data) {
		log_t log;
		log.current_tid = tid;
		log.crashed_tid = tid;
		log.tfd = tombstone_fd;
		log.amfd_data = amfd_data;
		dump_crash(&log, map, open_files, pid, tid, process_name, threads, abort_msg_address);
		dump_crash(&log, map, map_new, open_files, pid, tid, process_name, threads, abort_msg_address);
		}

		void engrave_tombstone_ucontext(int tombstone_fd, uintptr_t abort_msg_address, siginfo_t* siginfo,