In case of an unexpected signal on the host we dump the thread stack
ourselves. We have to pass the context given to the signal handler,
as the signal handler is run on an alternate stack. Otherwise
libbacktrace can't dump the actual faulty part.
Bug:
18933933
Change-Id: Id2710d2fd44b7c3b3335973a9288979a5793638b
static constexpr bool kDumpHeapObjectOnSigsevg = false;
struct Backtrace {
+ public:
+ explicit Backtrace(void* raw_context) : raw_context_(raw_context) {}
void Dump(std::ostream& os) const {
- DumpNativeStack(os, GetTid(), "\t");
+ DumpNativeStack(os, GetTid(), "\t", nullptr, raw_context_);
}
+ private:
+ // Stores the context of the signal that was unexpected and will terminate the runtime. The
+ // DumpNativeStack code will take care of casting it to the expected type. This is required
+ // as our signal handler runs on an alternate stack.
+ void* raw_context_;
};
struct OsInfo {
pid_t tid = GetTid();
std::string thread_name(GetThreadName(tid));
UContext thread_context(raw_context);
- Backtrace thread_backtrace;
+ Backtrace thread_backtrace(raw_context);
LOG(INTERNAL_FATAL) << "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n"
<< StringPrintf("Fatal signal %d (%s), code %d (%s)",
}
void DumpNativeStack(std::ostream& os, pid_t tid, const char* prefix,
- mirror::ArtMethod* current_method) {
+ mirror::ArtMethod* current_method, void* ucontext_ptr) {
#if __linux__
// b/18119146
if (RUNNING_ON_VALGRIND != 0) {
#endif
std::unique_ptr<Backtrace> backtrace(Backtrace::Create(BACKTRACE_CURRENT_PROCESS, tid));
- if (!backtrace->Unwind(0)) {
+ if (!backtrace->Unwind(0, reinterpret_cast<ucontext*>(ucontext_ptr))) {
os << prefix << "(backtrace::Unwind failed for thread " << tid << ")\n";
return;
} else if (backtrace->NumFrames() == 0) {
// Dumps the native stack for thread 'tid' to 'os'.
void DumpNativeStack(std::ostream& os, pid_t tid, const char* prefix = "",
- mirror::ArtMethod* current_method = nullptr)
+ mirror::ArtMethod* current_method = nullptr, void* ucontext = nullptr)
NO_THREAD_SAFETY_ANALYSIS;
// Dumps the kernel stack for thread 'tid' to 'os'. Note that this is only available on linux-x86.