/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "runtime.h"
#include <signal.h>
#include <string.h>
#include <sys/utsname.h>
#include <inttypes.h>
#include <sstream>
#include "base/dumpable.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/mutex.h"
#include "base/stringprintf.h"
#include "thread-inl.h"
#include "thread_list.h"
#include "utils.h"
namespace art {
static constexpr bool kDumpHeapObjectOnSigsevg = false;
static constexpr bool kUseSigRTTimeout = true;
static constexpr bool kDumpNativeStackOnTimeout = true;
struct Backtrace {
public:
explicit Backtrace(void* raw_context) : raw_context_(raw_context) {}
void Dump(std::ostream& os) const {
DumpNativeStack(os, GetTid(), nullptr, "\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 {
void Dump(std::ostream& os) const {
utsname info;
uname(&info);
// Linux 2.6.38.8-gg784 (x86_64)
// Darwin 11.4.0 (x86_64)
os << info.sysname << " " << info.release << " (" << info.machine << ")";
}
};
static const char* GetSignalName(int signal_number) {
switch (signal_number) {
case SIGABRT: return "SIGABRT";
case SIGBUS: return "SIGBUS";
case SIGFPE: return "SIGFPE";
case SIGILL: return "SIGILL";
case SIGPIPE: return "SIGPIPE";
case SIGSEGV: return "SIGSEGV";
#if defined(SIGSTKFLT)
case SIGSTKFLT: return "SIGSTKFLT";
#endif
case SIGTRAP: return "SIGTRAP";
}
return "??";
}
static const char* GetSignalCodeName(int signal_number, int signal_code) {
// Try the signal-specific codes...
switch (signal_number) {
case SIGILL:
switch (signal_code) {
case ILL_ILLOPC: return "ILL_ILLOPC";
case ILL_ILLOPN: return "ILL_ILLOPN";
case ILL_ILLADR: return "ILL_ILLADR";
case ILL_ILLTRP: return "ILL_ILLTRP";
case ILL_PRVOPC: return "ILL_PRVOPC";
case ILL_PRVREG: return "ILL_PRVREG";
case ILL_COPROC: return "ILL_COPROC";
case ILL_BADSTK: return "ILL_BADSTK";
}
break;
case SIGBUS:
switch (signal_code) {
case BUS_ADRALN: return "BUS_ADRALN";
case BUS_ADRERR: return "BUS_ADRERR";
case BUS_OBJERR: return "BUS_OBJERR";
}
break;
case SIGFPE:
switch (signal_code) {
case FPE_INTDIV: return "FPE_INTDIV";
case FPE_INTOVF: return "FPE_INTOVF";
case FPE_FLTDIV: return "FPE_FLTDIV";
case FPE_FLTOVF: return "FPE_FLTOVF";
case FPE_FLTUND: return "FPE_FLTUND";
case FPE_FLTRES: return "FPE_FLTRES";
case FPE_FLTINV: return "FPE_FLTINV";
case FPE_FLTSUB: return "FPE_FLTSUB";
}
break;
case SIGSEGV:
switch (signal_code) {
case SEGV_MAPERR: return "SEGV_MAPERR";
case SEGV_ACCERR: return "SEGV_ACCERR";
#if defined(SEGV_BNDERR)
case SEGV_BNDERR: return "SEGV_BNDERR";
#endif
}
break;
case SIGTRAP:
switch (signal_code) {
case TRAP_BRKPT: return "TRAP_BRKPT";
case TRAP_TRACE: return "TRAP_TRACE";
}
break;
}
// Then the other codes...
switch (signal_code) {
case SI_USER: return "SI_USER";
#if defined(SI_KERNEL)
case SI_KERNEL: return "SI_KERNEL";
#endif
case SI_QUEUE: return "SI_QUEUE";
case SI_TIMER: return "SI_TIMER";
case SI_MESGQ: return "SI_MESGQ";
case SI_ASYNCIO: return "SI_ASYNCIO";
#if defined(SI_SIGIO)
case SI_SIGIO: return "SI_SIGIO";
#endif
#if defined(SI_TKILL)
case SI_TKILL: return "SI_TKILL";
#endif
}
// Then give up...
return "?";
}
struct UContext {
explicit UContext(void* raw_context) :
context(reinterpret_cast<ucontext_t*>(raw_context)->uc_mcontext) {
}
void Dump(std::ostream& os) const {
// TODO: support non-x86 hosts (not urgent because this code doesn't run on targets).
#if defined(__APPLE__) && defined(__i386__)
DumpRegister32(os, "eax", context->__ss.__eax);
DumpRegister32(os, "ebx", context->__ss.__ebx);
DumpRegister32(os, "ecx", context->__ss.__ecx);
DumpRegister32(os, "edx", context->__ss.__edx);
os << '\n';
DumpRegister32(os, "edi", context->__ss.__edi);
DumpRegister32(os, "esi", context->__ss.__esi);
DumpRegister32(os, "ebp", context->__ss.__ebp);
DumpRegister32(os, "esp", context->__ss.__esp);
os << '\n';
DumpRegister32(os, "eip", context->__ss.__eip);
os << " ";
DumpRegister32(os, "eflags", context->__ss.__eflags);
DumpX86Flags(os, context->__ss.__eflags);
os << '\n';
DumpRegister32(os, "cs", context->__ss.__cs);
DumpRegister32(os, "ds", context->__ss.__ds);
DumpRegister32(os, "es", context->__ss.__es);
DumpRegister32(os, "fs", context->__ss.__fs);
os << '\n';
DumpRegister32(os, "gs", context->__ss.__gs);
DumpRegister32(os, "ss", context->__ss.__ss);
#elif defined(__linux__) && defined(__i386__)
DumpRegister32(os, "eax", context.gregs[REG_EAX]);
DumpRegister32(os, "ebx", context.gregs[REG_EBX]);
DumpRegister32(os, "ecx", context.gregs[REG_ECX]);
DumpRegister32(os, "edx", context.gregs[REG_EDX]);
os << '\n';
DumpRegister32(os, "edi", context.gregs[REG_EDI]);
DumpRegister32(os, "esi", context.gregs[REG_ESI]);
DumpRegister32(os, "ebp", context.gregs[REG_EBP]);
DumpRegister32(os, "esp", context.gregs[REG_ESP]);
os << '\n';
DumpRegister32(os, "eip", context.gregs[REG_EIP]);
os << " ";
DumpRegister32(os, "eflags", context.gregs[REG_EFL]);
DumpX86Flags(os, context.gregs[REG_EFL]);
os << '\n';
DumpRegister32(os, "cs", context.gregs[REG_CS]);
DumpRegister32(os, "ds", context.gregs[REG_DS]);
DumpRegister32(os, "es", context.gregs[REG_ES]);
DumpRegister32(os, "fs", context.gregs[REG_FS]);
os << '\n';
DumpRegister32(os, "gs", context.gregs[REG_GS]);
DumpRegister32(os, "ss", context.gregs[REG_SS]);
#elif defined(__linux__) && defined(__x86_64__)
DumpRegister64(os, "rax", context.gregs[REG_RAX]);
DumpRegister64(os, "rbx", context.gregs[REG_RBX]);
DumpRegister64(os, "rcx", context.gregs[REG_RCX]);
DumpRegister64(os, "rdx", context.gregs[REG_RDX]);
os << '\n';
DumpRegister64(os, "rdi", context.gregs[REG_RDI]);
DumpRegister64(os, "rsi", context.gregs[REG_RSI]);
DumpRegister64(os, "rbp", context.gregs[REG_RBP]);
DumpRegister64(os, "rsp", context.gregs[REG_RSP]);
os << '\n';
DumpRegister64(os, "r8 ", context.gregs[REG_R8]);
DumpRegister64(os, "r9 ", context.gregs[REG_R9]);
DumpRegister64(os, "r10", context.gregs[REG_R10]);
DumpRegister64(os, "r11", context.gregs[REG_R11]);
os << '\n';
DumpRegister64(os, "r12", context.gregs[REG_R12]);
DumpRegister64(os, "r13", context.gregs[REG_R13]);
DumpRegister64(os, "r14", context.gregs[REG_R14]);
DumpRegister64(os, "r15", context.gregs[REG_R15]);
os << '\n';
DumpRegister64(os, "rip", context.gregs[REG_RIP]);
os << " ";
DumpRegister32(os, "eflags", context.gregs[REG_EFL]);
DumpX86Flags(os, context.gregs[REG_EFL]);
os << '\n';
DumpRegister32(os, "cs", (context.gregs[REG_CSGSFS]) & 0x0FFFF);
DumpRegister32(os, "gs", (context.gregs[REG_CSGSFS] >> 16) & 0x0FFFF);
DumpRegister32(os, "fs", (context.gregs[REG_CSGSFS] >> 32) & 0x0FFFF);
os << '\n';
#else
os << "Unknown architecture/word size/OS in ucontext dump";
#endif
}
void DumpRegister32(std::ostream& os, const char* name, uint32_t value) const {
os << StringPrintf(" %6s: 0x%08x", name, value);
}
void DumpRegister64(std::ostream& os, const char* name, uint64_t value) const {
os << StringPrintf(" %6s: 0x%016" PRIx64, name, value);
}
void DumpX86Flags(std::ostream& os, uint32_t flags) const {
os << " [";
if ((flags & (1 << 0)) != 0) {
os << " CF";
}
if ((flags & (1 << 2)) != 0) {
os << " PF";
}
if ((flags & (1 << 4)) != 0) {
os << " AF";
}
if ((flags & (1 << 6)) != 0) {
os << " ZF";
}
if ((flags & (1 << 7)) != 0) {
os << " SF";
}
if ((flags & (1 << 8)) != 0) {
os << " TF";
}
if ((flags & (1 << 9)) != 0) {
os << " IF";
}
if ((flags & (1 << 10)) != 0) {
os << " DF";
}
if ((flags & (1 << 11)) != 0) {
os << " OF";
}
os << " ]";
}
mcontext_t& context;
};
// Return the signal number we recognize as timeout. -1 means not active/supported.
static int GetTimeoutSignal() {
#if defined(__APPLE__)
// Mac does not support realtime signals.
UNUSED(kUseSigRTTimeout);
return -1;
#else
return kUseSigRTTimeout ? (SIGRTMIN + 2) : -1;
#endif
}
static bool IsTimeoutSignal(int signal_number) {
return signal_number == GetTimeoutSignal();
}
void HandleUnexpectedSignal(int signal_number, siginfo_t* info, void* raw_context) {
static bool handlingUnexpectedSignal = false;
if (handlingUnexpectedSignal) {
LogMessage::LogLine(__FILE__, __LINE__, INTERNAL_FATAL, "HandleUnexpectedSignal reentered\n");
if (IsTimeoutSignal(signal_number)) {
// Ignore a recursive timeout.
return;
}
_exit(1);
}
handlingUnexpectedSignal = true;
gAborting++; // set before taking any locks
MutexLock mu(Thread::Current(), *Locks::unexpected_signal_lock_);
bool has_address = (signal_number == SIGILL || signal_number == SIGBUS ||
signal_number == SIGFPE || signal_number == SIGSEGV);
OsInfo os_info;
const char* cmd_line = GetCmdLine();
if (cmd_line == nullptr) {
cmd_line = "<unset>"; // Because no-one called InitLogging.
}
pid_t tid = GetTid();
std::string thread_name(GetThreadName(tid));
UContext thread_context(raw_context);
Backtrace thread_backtrace(raw_context);
LOG(INTERNAL_FATAL) << "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n"
<< StringPrintf("Fatal signal %d (%s), code %d (%s)",
signal_number, GetSignalName(signal_number),
info->si_code,
GetSignalCodeName(signal_number, info->si_code))
<< (has_address ? StringPrintf(" fault addr %p", info->si_addr) : "") << "\n"
<< "OS: " << Dumpable<OsInfo>(os_info) << "\n"
<< "Cmdline: " << cmd_line << "\n"
<< "Thread: " << tid << " \"" << thread_name << "\"\n"
<< "Registers:\n" << Dumpable<UContext>(thread_context) << "\n"
<< "Backtrace:\n" << Dumpable<Backtrace>(thread_backtrace);
if (kIsDebugBuild && signal_number == SIGSEGV) {
PrintFileToLog("/proc/self/maps", LogSeverity::INTERNAL_FATAL);
}
Runtime* runtime = Runtime::Current();
if (runtime != nullptr) {
if (IsTimeoutSignal(signal_number)) {
// Special timeout signal. Try to dump all threads.
// Note: Do not use DumpForSigQuit, as that might disable native unwind, but the native parts
// are of value here.
runtime->GetThreadList()->Dump(LOG(INTERNAL_FATAL), kDumpNativeStackOnTimeout);
}
gc::Heap* heap = runtime->GetHeap();
LOG(INTERNAL_FATAL) << "Fault message: " << runtime->GetFaultMessage();
if (kDumpHeapObjectOnSigsevg && heap != nullptr && info != nullptr) {
LOG(INTERNAL_FATAL) << "Dump heap object at fault address: ";
heap->DumpObject(LOG(INTERNAL_FATAL), reinterpret_cast<mirror::Object*>(info->si_addr));
}
}
if (getenv("debug_db_uid") != nullptr || getenv("art_wait_for_gdb_on_crash") != nullptr) {
LOG(INTERNAL_FATAL) << "********************************************************\n"
<< "* Process " << getpid() << " thread " << tid << " \"" << thread_name
<< "\""
<< " has been suspended while crashing.\n"
<< "* Attach gdb:\n"
<< "* gdb -p " << tid << "\n"
<< "********************************************************\n";
// Wait for debugger to attach.
while (true) {
}
}
#ifdef __linux__
// Remove our signal handler for this signal...
struct sigaction action;
memset(&action, 0, sizeof(action));
sigemptyset(&action.sa_mask);
action.sa_handler = SIG_DFL;
sigaction(signal_number, &action, nullptr);
// ...and re-raise so we die with the appropriate status.
kill(getpid(), signal_number);
#else
exit(EXIT_FAILURE);
#endif
}
void Runtime::InitPlatformSignalHandlers() {
// On the host, we don't have debuggerd to dump a stack for us when something unexpected happens.
struct sigaction action;
memset(&action, 0, sizeof(action));
sigemptyset(&action.sa_mask);
action.sa_sigaction = HandleUnexpectedSignal;
// Use the three-argument sa_sigaction handler.
action.sa_flags |= SA_SIGINFO;
// Use the alternate signal stack so we can catch stack overflows.
action.sa_flags |= SA_ONSTACK;
int rc = 0;
rc += sigaction(SIGABRT, &action, nullptr);
rc += sigaction(SIGBUS, &action, nullptr);
rc += sigaction(SIGFPE, &action, nullptr);
rc += sigaction(SIGILL, &action, nullptr);
rc += sigaction(SIGPIPE, &action, nullptr);
rc += sigaction(SIGSEGV, &action, nullptr);
#if defined(SIGSTKFLT)
rc += sigaction(SIGSTKFLT, &action, nullptr);
#endif
rc += sigaction(SIGTRAP, &action, nullptr);
// Special dump-all timeout.
if (GetTimeoutSignal() != -1) {
rc += sigaction(GetTimeoutSignal(), &action, nullptr);
}
CHECK_EQ(rc, 0);
}
} // namespace art