Merge "Compare new unwinder to old unwinder in debuggerd."
am: bb2f03f344
Change-Id: I3e51fadda629f7d4bda8e4ddc4c0b60ebbdb49b8
diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index f86aaa0..7d17cd9 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -106,6 +106,7 @@
"libdebuggerd",
"libbacktrace",
"libunwind",
+ "libunwindstack",
"liblzma",
"libcutils",
],
@@ -171,6 +172,7 @@
static_libs: [
"libbacktrace",
"libunwind",
+ "libunwindstack",
"liblzma",
"libbase",
"libcutils",
diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index 4b1e51d..34ad7de 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -329,6 +329,11 @@
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 @@
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
diff --git a/debuggerd/libdebuggerd/include/tombstone.h b/debuggerd/libdebuggerd/include/tombstone.h
index 79743b6..45740df 100644
--- a/debuggerd/libdebuggerd/include/tombstone.h
+++ b/debuggerd/libdebuggerd/include/tombstone.h
@@ -35,10 +35,10 @@
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);
diff --git a/debuggerd/libdebuggerd/tombstone.cpp b/debuggerd/libdebuggerd/tombstone.cpp
index 0113131..b809ed4 100644
--- a/debuggerd/libdebuggerd/tombstone.cpp
+++ b/debuggerd/libdebuggerd/tombstone.cpp
@@ -495,8 +495,55 @@
_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 @@
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 @@
}
log->current_tid = log->crashed_tid;
+
+ return matches;
}
// Reads the contents of the specified log device, filters out the entries
@@ -657,9 +717,10 @@
}
// 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 @@
_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 @@
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 @@
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 @@
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,