1 /* 2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "asm/macroAssembler.hpp" 27 #include "classfile/classLoader.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/icBuffer.hpp" 31 #include "code/vtableStubs.hpp" 32 #include "interpreter/interpreter.hpp" 33 #include "jvm_bsd.h" 34 #include "memory/allocation.inline.hpp" 35 #include "mutex_bsd.inline.hpp" 36 #include "os_share_bsd.hpp" 37 #include "prims/jniFastGetField.hpp" 38 #include "prims/jvm.h" 39 #include "prims/jvm_misc.hpp" 40 #include "runtime/arguments.hpp" 41 #include "runtime/extendedPC.hpp" 42 #include "runtime/frame.inline.hpp" 43 #include "runtime/interfaceSupport.hpp" 44 #include "runtime/java.hpp" 45 #include "runtime/javaCalls.hpp" 46 #include "runtime/mutexLocker.hpp" 47 #include "runtime/osThread.hpp" 48 #include "runtime/sharedRuntime.hpp" 49 #include "runtime/stubRoutines.hpp" 50 #include "runtime/thread.inline.hpp" 51 #include "runtime/timer.hpp" 52 #include "utilities/events.hpp" 53 #include "utilities/vmError.hpp" 54 55 // put OS-includes here 56 # include <sys/types.h> 57 # include <sys/mman.h> 58 # include <pthread.h> 59 # include <signal.h> 60 # include <errno.h> 61 # include <dlfcn.h> 62 # include <stdlib.h> 63 # include <stdio.h> 64 # include <unistd.h> 65 # include <sys/resource.h> 66 # include <pthread.h> 67 # include <sys/stat.h> 68 # include <sys/time.h> 69 # include <sys/utsname.h> 70 # include <sys/socket.h> 71 # include <sys/wait.h> 72 # include <pwd.h> 73 # include <poll.h> 74 #ifndef __OpenBSD__ 75 # include <ucontext.h> 76 #endif 77 78 #if !defined(__APPLE__) && !defined(__NetBSD__) 79 # include <pthread_np.h> 80 #endif 81 82 // needed by current_stack_region() workaround for Mavericks 83 #if defined(__APPLE__) 84 # include <errno.h> 85 # include <sys/types.h> 86 # include <sys/sysctl.h> 87 # define DEFAULT_MAIN_THREAD_STACK_PAGES 2048 88 # define OS_X_10_9_0_KERNEL_MAJOR_VERSION 13 89 #endif 90 91 #ifdef AMD64 92 #define SPELL_REG_SP "rsp" 93 #define SPELL_REG_FP "rbp" 94 #else 95 #define SPELL_REG_SP "esp" 96 #define SPELL_REG_FP "ebp" 97 #endif // AMD64 98 99 #ifdef __FreeBSD__ 100 # define context_trapno uc_mcontext.mc_trapno 101 # ifdef AMD64 102 # define context_pc uc_mcontext.mc_rip 103 # define context_sp uc_mcontext.mc_rsp 104 # define context_fp uc_mcontext.mc_rbp 105 # define context_rip uc_mcontext.mc_rip 106 # define context_rsp uc_mcontext.mc_rsp 107 # define context_rbp uc_mcontext.mc_rbp 108 # define context_rax uc_mcontext.mc_rax 109 # define context_rbx uc_mcontext.mc_rbx 110 # define context_rcx uc_mcontext.mc_rcx 111 # define context_rdx uc_mcontext.mc_rdx 112 # define context_rsi uc_mcontext.mc_rsi 113 # define context_rdi uc_mcontext.mc_rdi 114 # define context_r8 uc_mcontext.mc_r8 115 # define context_r9 uc_mcontext.mc_r9 116 # define context_r10 uc_mcontext.mc_r10 117 # define context_r11 uc_mcontext.mc_r11 118 # define context_r12 uc_mcontext.mc_r12 119 # define context_r13 uc_mcontext.mc_r13 120 # define context_r14 uc_mcontext.mc_r14 121 # define context_r15 uc_mcontext.mc_r15 122 # define context_flags uc_mcontext.mc_flags 123 # define context_err uc_mcontext.mc_err 124 # else 125 # define context_pc uc_mcontext.mc_eip 126 # define context_sp uc_mcontext.mc_esp 127 # define context_fp uc_mcontext.mc_ebp 128 # define context_eip uc_mcontext.mc_eip 129 # define context_esp uc_mcontext.mc_esp 130 # define context_eax uc_mcontext.mc_eax 131 # define context_ebx uc_mcontext.mc_ebx 132 # define context_ecx uc_mcontext.mc_ecx 133 # define context_edx uc_mcontext.mc_edx 134 # define context_ebp uc_mcontext.mc_ebp 135 # define context_esi uc_mcontext.mc_esi 136 # define context_edi uc_mcontext.mc_edi 137 # define context_eflags uc_mcontext.mc_eflags 138 # define context_trapno uc_mcontext.mc_trapno 139 # endif 140 #endif 141 142 #ifdef __APPLE__ 143 # if __DARWIN_UNIX03 && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5) 144 // 10.5 UNIX03 member name prefixes 145 #define DU3_PREFIX(s, m) __ ## s.__ ## m 146 # else 147 #define DU3_PREFIX(s, m) s ## . ## m 148 # endif 149 150 # ifdef AMD64 151 # define context_pc context_rip 152 # define context_sp context_rsp 153 # define context_fp context_rbp 154 # define context_rip uc_mcontext->DU3_PREFIX(ss,rip) 155 # define context_rsp uc_mcontext->DU3_PREFIX(ss,rsp) 156 # define context_rax uc_mcontext->DU3_PREFIX(ss,rax) 157 # define context_rbx uc_mcontext->DU3_PREFIX(ss,rbx) 158 # define context_rcx uc_mcontext->DU3_PREFIX(ss,rcx) 159 # define context_rdx uc_mcontext->DU3_PREFIX(ss,rdx) 160 # define context_rbp uc_mcontext->DU3_PREFIX(ss,rbp) 161 # define context_rsi uc_mcontext->DU3_PREFIX(ss,rsi) 162 # define context_rdi uc_mcontext->DU3_PREFIX(ss,rdi) 163 # define context_r8 uc_mcontext->DU3_PREFIX(ss,r8) 164 # define context_r9 uc_mcontext->DU3_PREFIX(ss,r9) 165 # define context_r10 uc_mcontext->DU3_PREFIX(ss,r10) 166 # define context_r11 uc_mcontext->DU3_PREFIX(ss,r11) 167 # define context_r12 uc_mcontext->DU3_PREFIX(ss,r12) 168 # define context_r13 uc_mcontext->DU3_PREFIX(ss,r13) 169 # define context_r14 uc_mcontext->DU3_PREFIX(ss,r14) 170 # define context_r15 uc_mcontext->DU3_PREFIX(ss,r15) 171 # define context_flags uc_mcontext->DU3_PREFIX(ss,rflags) 172 # define context_trapno uc_mcontext->DU3_PREFIX(es,trapno) 173 # define context_err uc_mcontext->DU3_PREFIX(es,err) 174 # else 175 # define context_pc context_eip 176 # define context_sp context_esp 177 # define context_fp context_ebp 178 # define context_eip uc_mcontext->DU3_PREFIX(ss,eip) 179 # define context_esp uc_mcontext->DU3_PREFIX(ss,esp) 180 # define context_eax uc_mcontext->DU3_PREFIX(ss,eax) 181 # define context_ebx uc_mcontext->DU3_PREFIX(ss,ebx) 182 # define context_ecx uc_mcontext->DU3_PREFIX(ss,ecx) 183 # define context_edx uc_mcontext->DU3_PREFIX(ss,edx) 184 # define context_ebp uc_mcontext->DU3_PREFIX(ss,ebp) 185 # define context_esi uc_mcontext->DU3_PREFIX(ss,esi) 186 # define context_edi uc_mcontext->DU3_PREFIX(ss,edi) 187 # define context_eflags uc_mcontext->DU3_PREFIX(ss,eflags) 188 # define context_trapno uc_mcontext->DU3_PREFIX(es,trapno) 189 # endif 190 #endif 191 192 #ifdef __OpenBSD__ 193 # define context_trapno sc_trapno 194 # ifdef AMD64 195 # define context_pc sc_rip 196 # define context_sp sc_rsp 197 # define context_fp sc_rbp 198 # define context_rip sc_rip 199 # define context_rsp sc_rsp 200 # define context_rbp sc_rbp 201 # define context_rax sc_rax 202 # define context_rbx sc_rbx 203 # define context_rcx sc_rcx 204 # define context_rdx sc_rdx 205 # define context_rsi sc_rsi 206 # define context_rdi sc_rdi 207 # define context_r8 sc_r8 208 # define context_r9 sc_r9 209 # define context_r10 sc_r10 210 # define context_r11 sc_r11 211 # define context_r12 sc_r12 212 # define context_r13 sc_r13 213 # define context_r14 sc_r14 214 # define context_r15 sc_r15 215 # define context_flags sc_rflags 216 # define context_err sc_err 217 # else 218 # define context_pc sc_eip 219 # define context_sp sc_esp 220 # define context_fp sc_ebp 221 # define context_eip sc_eip 222 # define context_esp sc_esp 223 # define context_eax sc_eax 224 # define context_ebx sc_ebx 225 # define context_ecx sc_ecx 226 # define context_edx sc_edx 227 # define context_ebp sc_ebp 228 # define context_esi sc_esi 229 # define context_edi sc_edi 230 # define context_eflags sc_eflags 231 # define context_trapno sc_trapno 232 # endif 233 #endif 234 235 #ifdef __NetBSD__ 236 # define context_trapno uc_mcontext.__gregs[_REG_TRAPNO] 237 # ifdef AMD64 238 # define __register_t __greg_t 239 # define context_pc uc_mcontext.__gregs[_REG_RIP] 240 # define context_sp uc_mcontext.__gregs[_REG_URSP] 241 # define context_fp uc_mcontext.__gregs[_REG_RBP] 242 # define context_rip uc_mcontext.__gregs[_REG_RIP] 243 # define context_rsp uc_mcontext.__gregs[_REG_URSP] 244 # define context_rax uc_mcontext.__gregs[_REG_RAX] 245 # define context_rbx uc_mcontext.__gregs[_REG_RBX] 246 # define context_rcx uc_mcontext.__gregs[_REG_RCX] 247 # define context_rdx uc_mcontext.__gregs[_REG_RDX] 248 # define context_rbp uc_mcontext.__gregs[_REG_RBP] 249 # define context_rsi uc_mcontext.__gregs[_REG_RSI] 250 # define context_rdi uc_mcontext.__gregs[_REG_RDI] 251 # define context_r8 uc_mcontext.__gregs[_REG_R8] 252 # define context_r9 uc_mcontext.__gregs[_REG_R9] 253 # define context_r10 uc_mcontext.__gregs[_REG_R10] 254 # define context_r11 uc_mcontext.__gregs[_REG_R11] 255 # define context_r12 uc_mcontext.__gregs[_REG_R12] 256 # define context_r13 uc_mcontext.__gregs[_REG_R13] 257 # define context_r14 uc_mcontext.__gregs[_REG_R14] 258 # define context_r15 uc_mcontext.__gregs[_REG_R15] 259 # define context_flags uc_mcontext.__gregs[_REG_RFL] 260 # define context_err uc_mcontext.__gregs[_REG_ERR] 261 # else 262 # define context_pc uc_mcontext.__gregs[_REG_EIP] 263 # define context_sp uc_mcontext.__gregs[_REG_UESP] 264 # define context_fp uc_mcontext.__gregs[_REG_EBP] 265 # define context_eip uc_mcontext.__gregs[_REG_EIP] 266 # define context_esp uc_mcontext.__gregs[_REG_UESP] 267 # define context_eax uc_mcontext.__gregs[_REG_EAX] 268 # define context_ebx uc_mcontext.__gregs[_REG_EBX] 269 # define context_ecx uc_mcontext.__gregs[_REG_ECX] 270 # define context_edx uc_mcontext.__gregs[_REG_EDX] 271 # define context_ebp uc_mcontext.__gregs[_REG_EBP] 272 # define context_esi uc_mcontext.__gregs[_REG_ESI] 273 # define context_edi uc_mcontext.__gregs[_REG_EDI] 274 # define context_eflags uc_mcontext.__gregs[_REG_EFL] 275 # define context_trapno uc_mcontext.__gregs[_REG_TRAPNO] 276 # endif 277 #endif 278 279 address os::current_stack_pointer() { 280 #if defined(__clang__) || defined(__llvm__) 281 register void *esp; 282 __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp)); 283 return (address) esp; 284 #elif defined(SPARC_WORKS) 285 register void *esp; 286 __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp)); 287 return (address) ((char*)esp + sizeof(long)*2); 288 #else 289 register void *esp __asm__ (SPELL_REG_SP); 290 return (address) esp; 291 #endif 292 } 293 294 char* os::non_memory_address_word() { 295 // Must never look like an address returned by reserve_memory, 296 // even in its subfields (as defined by the CPU immediate fields, 297 // if the CPU splits constants across multiple instructions). 298 299 return (char*) -1; 300 } 301 302 void os::initialize_thread(Thread* thr) { 303 // Nothing to do. 304 } 305 306 address os::Bsd::ucontext_get_pc(ucontext_t * uc) { 307 return (address)uc->context_pc; 308 } 309 310 intptr_t* os::Bsd::ucontext_get_sp(ucontext_t * uc) { 311 return (intptr_t*)uc->context_sp; 312 } 313 314 intptr_t* os::Bsd::ucontext_get_fp(ucontext_t * uc) { 315 return (intptr_t*)uc->context_fp; 316 } 317 318 // For Forte Analyzer AsyncGetCallTrace profiling support - thread 319 // is currently interrupted by SIGPROF. 320 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal 321 // frames. Currently we don't do that on Bsd, so it's the same as 322 // os::fetch_frame_from_context(). 323 ExtendedPC os::Bsd::fetch_frame_from_ucontext(Thread* thread, 324 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 325 326 assert(thread != NULL, "just checking"); 327 assert(ret_sp != NULL, "just checking"); 328 assert(ret_fp != NULL, "just checking"); 329 330 return os::fetch_frame_from_context(uc, ret_sp, ret_fp); 331 } 332 333 ExtendedPC os::fetch_frame_from_context(void* ucVoid, 334 intptr_t** ret_sp, intptr_t** ret_fp) { 335 336 ExtendedPC epc; 337 ucontext_t* uc = (ucontext_t*)ucVoid; 338 339 if (uc != NULL) { 340 epc = ExtendedPC(os::Bsd::ucontext_get_pc(uc)); 341 if (ret_sp) *ret_sp = os::Bsd::ucontext_get_sp(uc); 342 if (ret_fp) *ret_fp = os::Bsd::ucontext_get_fp(uc); 343 } else { 344 // construct empty ExtendedPC for return value checking 345 epc = ExtendedPC(NULL); 346 if (ret_sp) *ret_sp = (intptr_t *)NULL; 347 if (ret_fp) *ret_fp = (intptr_t *)NULL; 348 } 349 350 return epc; 351 } 352 353 frame os::fetch_frame_from_context(void* ucVoid) { 354 intptr_t* sp; 355 intptr_t* fp; 356 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 357 return frame(sp, fp, epc.pc()); 358 } 359 360 // By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get 361 // turned off by -fomit-frame-pointer, 362 frame os::get_sender_for_C_frame(frame* fr) { 363 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 364 } 365 366 intptr_t* _get_previous_fp() { 367 #if defined(SPARC_WORKS) || defined(__clang__) || defined(__llvm__) 368 register intptr_t **ebp; 369 __asm__("mov %%"SPELL_REG_FP", %0":"=r"(ebp)); 370 #else 371 register intptr_t **ebp __asm__ (SPELL_REG_FP); 372 #endif 373 return (intptr_t*) *ebp; // we want what it points to. 374 } 375 376 377 frame os::current_frame() { 378 intptr_t* fp = _get_previous_fp(); 379 frame myframe((intptr_t*)os::current_stack_pointer(), 380 (intptr_t*)fp, 381 CAST_FROM_FN_PTR(address, os::current_frame)); 382 if (os::is_first_C_frame(&myframe)) { 383 // stack is not walkable 384 return frame(); 385 } else { 386 return os::get_sender_for_C_frame(&myframe); 387 } 388 } 389 390 // Utility functions 391 392 // From IA32 System Programming Guide 393 enum { 394 trap_page_fault = 0xE 395 }; 396 397 extern "C" JNIEXPORT int 398 JVM_handle_bsd_signal(int sig, 399 siginfo_t* info, 400 void* ucVoid, 401 int abort_if_unrecognized) { 402 ucontext_t* uc = (ucontext_t*) ucVoid; 403 404 Thread* t = ThreadLocalStorage::get_thread_slow(); 405 406 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away 407 // (no destructors can be run) 408 os::WatcherThreadCrashProtection::check_crash_protection(sig, t); 409 410 SignalHandlerMark shm(t); 411 412 // Note: it's not uncommon that JNI code uses signal/sigset to install 413 // then restore certain signal handler (e.g. to temporarily block SIGPIPE, 414 // or have a SIGILL handler when detecting CPU type). When that happens, 415 // JVM_handle_bsd_signal() might be invoked with junk info/ucVoid. To 416 // avoid unnecessary crash when libjsig is not preloaded, try handle signals 417 // that do not require siginfo/ucontext first. 418 419 if (sig == SIGPIPE || sig == SIGXFSZ) { 420 // allow chained handler to go first 421 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 422 return true; 423 } else { 424 if (PrintMiscellaneous && (WizardMode || Verbose)) { 425 char buf[64]; 426 warning("Ignoring %s - see bugs 4229104 or 646499219", 427 os::exception_name(sig, buf, sizeof(buf))); 428 } 429 return true; 430 } 431 } 432 433 JavaThread* thread = NULL; 434 VMThread* vmthread = NULL; 435 if (os::Bsd::signal_handlers_are_installed) { 436 if (t != NULL ){ 437 if(t->is_Java_thread()) { 438 thread = (JavaThread*)t; 439 } 440 else if(t->is_VM_thread()){ 441 vmthread = (VMThread *)t; 442 } 443 } 444 } 445 /* 446 NOTE: does not seem to work on bsd. 447 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 448 // can't decode this kind of signal 449 info = NULL; 450 } else { 451 assert(sig == info->si_signo, "bad siginfo"); 452 } 453 */ 454 // decide if this trap can be handled by a stub 455 address stub = NULL; 456 457 address pc = NULL; 458 459 //%note os_trap_1 460 if (info != NULL && uc != NULL && thread != NULL) { 461 pc = (address) os::Bsd::ucontext_get_pc(uc); 462 463 if (StubRoutines::is_safefetch_fault(pc)) { 464 uc->context_pc = intptr_t(StubRoutines::continuation_for_safefetch_fault(pc)); 465 return 1; 466 } 467 468 // Handle ALL stack overflow variations here 469 if (sig == SIGSEGV || sig == SIGBUS) { 470 address addr = (address) info->si_addr; 471 472 // check if fault address is within thread stack 473 if (addr < thread->stack_base() && 474 addr >= thread->stack_base() - thread->stack_size()) { 475 // stack overflow 476 if (thread->in_stack_yellow_zone(addr)) { 477 thread->disable_stack_yellow_zone(); 478 if (thread->thread_state() == _thread_in_Java) { 479 // Throw a stack overflow exception. Guard pages will be reenabled 480 // while unwinding the stack. 481 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 482 } else { 483 // Thread was in the vm or native code. Return and try to finish. 484 return 1; 485 } 486 } else if (thread->in_stack_red_zone(addr)) { 487 // Fatal red zone violation. Disable the guard pages and fall through 488 // to handle_unexpected_exception way down below. 489 thread->disable_stack_red_zone(); 490 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 491 } 492 } 493 } 494 495 // We test if stub is already set (by the stack overflow code 496 // above) so it is not overwritten by the code that follows. This 497 // check is not required on other platforms, because on other 498 // platforms we check for SIGSEGV only or SIGBUS only, where here 499 // we have to check for both SIGSEGV and SIGBUS. 500 if (thread->thread_state() == _thread_in_Java && stub == NULL) { 501 // Java thread running in Java code => find exception handler if any 502 // a fault inside compiled code, the interpreter, or a stub 503 504 if ((sig == SIGSEGV || sig == SIGBUS) && os::is_poll_address((address)info->si_addr)) { 505 stub = SharedRuntime::get_poll_stub(pc); 506 #if defined(__APPLE__) 507 // 32-bit Darwin reports a SIGBUS for nearly all memory access exceptions. 508 // 64-bit Darwin may also use a SIGBUS (seen with compressed oops). 509 // Catching SIGBUS here prevents the implicit SIGBUS NULL check below from 510 // being called, so only do so if the implicit NULL check is not necessary. 511 } else if (sig == SIGBUS && MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 512 #else 513 } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) { 514 #endif 515 // BugId 4454115: A read from a MappedByteBuffer can fault 516 // here if the underlying file has been truncated. 517 // Do not crash the VM in such a case. 518 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 519 nmethod* nm = (cb != NULL && cb->is_nmethod()) ? (nmethod*)cb : NULL; 520 if (nm != NULL && nm->has_unsafe_access()) { 521 stub = StubRoutines::handler_for_unsafe_access(); 522 } 523 } 524 else 525 526 #ifdef AMD64 527 if (sig == SIGFPE && 528 (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) { 529 stub = 530 SharedRuntime:: 531 continuation_for_implicit_exception(thread, 532 pc, 533 SharedRuntime:: 534 IMPLICIT_DIVIDE_BY_ZERO); 535 #ifdef __APPLE__ 536 } else if (sig == SIGFPE && info->si_code == FPE_NOOP) { 537 int op = pc[0]; 538 539 // Skip REX 540 if ((pc[0] & 0xf0) == 0x40) { 541 op = pc[1]; 542 } else { 543 op = pc[0]; 544 } 545 546 // Check for IDIV 547 if (op == 0xF7) { 548 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime:: IMPLICIT_DIVIDE_BY_ZERO); 549 } else { 550 // TODO: handle more cases if we are using other x86 instructions 551 // that can generate SIGFPE signal. 552 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); 553 fatal("please update this code."); 554 } 555 #endif /* __APPLE__ */ 556 557 #else 558 if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) { 559 // HACK: si_code does not work on bsd 2.2.12-20!!! 560 int op = pc[0]; 561 if (op == 0xDB) { 562 // FIST 563 // TODO: The encoding of D2I in i486.ad can cause an exception 564 // prior to the fist instruction if there was an invalid operation 565 // pending. We want to dismiss that exception. From the win_32 566 // side it also seems that if it really was the fist causing 567 // the exception that we do the d2i by hand with different 568 // rounding. Seems kind of weird. 569 // NOTE: that we take the exception at the NEXT floating point instruction. 570 assert(pc[0] == 0xDB, "not a FIST opcode"); 571 assert(pc[1] == 0x14, "not a FIST opcode"); 572 assert(pc[2] == 0x24, "not a FIST opcode"); 573 return true; 574 } else if (op == 0xF7) { 575 // IDIV 576 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 577 } else { 578 // TODO: handle more cases if we are using other x86 instructions 579 // that can generate SIGFPE signal on bsd. 580 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); 581 fatal("please update this code."); 582 } 583 #endif // AMD64 584 } else if ((sig == SIGSEGV || sig == SIGBUS) && 585 !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 586 // Determination of interpreter/vtable stub/compiled code null exception 587 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 588 } 589 } else if (thread->thread_state() == _thread_in_vm && 590 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */ 591 thread->doing_unsafe_access()) { 592 stub = StubRoutines::handler_for_unsafe_access(); 593 } 594 595 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 596 // and the heap gets shrunk before the field access. 597 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 598 address addr = JNI_FastGetField::find_slowcase_pc(pc); 599 if (addr != (address)-1) { 600 stub = addr; 601 } 602 } 603 604 // Check to see if we caught the safepoint code in the 605 // process of write protecting the memory serialization page. 606 // It write enables the page immediately after protecting it 607 // so we can just return to retry the write. 608 if ((sig == SIGSEGV || sig == SIGBUS) && 609 os::is_memory_serialize_page(thread, (address) info->si_addr)) { 610 // Block current thread until the memory serialize page permission restored. 611 os::block_on_serialize_page_trap(); 612 return true; 613 } 614 } 615 616 #ifndef AMD64 617 // Execution protection violation 618 // 619 // This should be kept as the last step in the triage. We don't 620 // have a dedicated trap number for a no-execute fault, so be 621 // conservative and allow other handlers the first shot. 622 // 623 // Note: We don't test that info->si_code == SEGV_ACCERR here. 624 // this si_code is so generic that it is almost meaningless; and 625 // the si_code for this condition may change in the future. 626 // Furthermore, a false-positive should be harmless. 627 if (UnguardOnExecutionViolation > 0 && 628 (sig == SIGSEGV || sig == SIGBUS) && 629 uc->context_trapno == trap_page_fault) { 630 int page_size = os::vm_page_size(); 631 address addr = (address) info->si_addr; 632 address pc = os::Bsd::ucontext_get_pc(uc); 633 // Make sure the pc and the faulting address are sane. 634 // 635 // If an instruction spans a page boundary, and the page containing 636 // the beginning of the instruction is executable but the following 637 // page is not, the pc and the faulting address might be slightly 638 // different - we still want to unguard the 2nd page in this case. 639 // 640 // 15 bytes seems to be a (very) safe value for max instruction size. 641 bool pc_is_near_addr = 642 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 643 bool instr_spans_page_boundary = 644 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 645 (intptr_t) page_size) > 0); 646 647 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 648 static volatile address last_addr = 649 (address) os::non_memory_address_word(); 650 651 // In conservative mode, don't unguard unless the address is in the VM 652 if (addr != last_addr && 653 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 654 655 // Set memory to RWX and retry 656 address page_start = 657 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 658 bool res = os::protect_memory((char*) page_start, page_size, 659 os::MEM_PROT_RWX); 660 661 if (PrintMiscellaneous && Verbose) { 662 char buf[256]; 663 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 664 "at " INTPTR_FORMAT 665 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 666 page_start, (res ? "success" : "failed"), errno); 667 tty->print_raw_cr(buf); 668 } 669 stub = pc; 670 671 // Set last_addr so if we fault again at the same address, we don't end 672 // up in an endless loop. 673 // 674 // There are two potential complications here. Two threads trapping at 675 // the same address at the same time could cause one of the threads to 676 // think it already unguarded, and abort the VM. Likely very rare. 677 // 678 // The other race involves two threads alternately trapping at 679 // different addresses and failing to unguard the page, resulting in 680 // an endless loop. This condition is probably even more unlikely than 681 // the first. 682 // 683 // Although both cases could be avoided by using locks or thread local 684 // last_addr, these solutions are unnecessary complication: this 685 // handler is a best-effort safety net, not a complete solution. It is 686 // disabled by default and should only be used as a workaround in case 687 // we missed any no-execute-unsafe VM code. 688 689 last_addr = addr; 690 } 691 } 692 } 693 #endif // !AMD64 694 695 if (stub != NULL) { 696 // save all thread context in case we need to restore it 697 if (thread != NULL) thread->set_saved_exception_pc(pc); 698 699 uc->context_pc = (intptr_t)stub; 700 return true; 701 } 702 703 // signal-chaining 704 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 705 return true; 706 } 707 708 if (!abort_if_unrecognized) { 709 // caller wants another chance, so give it to him 710 return false; 711 } 712 713 if (pc == NULL && uc != NULL) { 714 pc = os::Bsd::ucontext_get_pc(uc); 715 } 716 717 // unmask current signal 718 sigset_t newset; 719 sigemptyset(&newset); 720 sigaddset(&newset, sig); 721 sigprocmask(SIG_UNBLOCK, &newset, NULL); 722 723 VMError err(t, sig, pc, info, ucVoid); 724 err.report_and_die(); 725 726 ShouldNotReachHere(); 727 return false; 728 } 729 730 // From solaris_i486.s ported to bsd_i486.s 731 extern "C" void fixcw(); 732 733 void os::Bsd::init_thread_fpu_state(void) { 734 #ifndef AMD64 735 // Set fpu to 53 bit precision. This happens too early to use a stub. 736 fixcw(); 737 #endif // !AMD64 738 } 739 740 741 // Check that the bsd kernel version is 2.4 or higher since earlier 742 // versions do not support SSE without patches. 743 bool os::supports_sse() { 744 return true; 745 } 746 747 bool os::is_allocatable(size_t bytes) { 748 #ifdef AMD64 749 // unused on amd64? 750 return true; 751 #else 752 753 if (bytes < 2 * G) { 754 return true; 755 } 756 757 char* addr = reserve_memory(bytes, NULL); 758 759 if (addr != NULL) { 760 release_memory(addr, bytes); 761 } 762 763 return addr != NULL; 764 #endif // AMD64 765 } 766 767 //////////////////////////////////////////////////////////////////////////////// 768 // thread stack 769 770 #ifdef AMD64 771 size_t os::Bsd::min_stack_allowed = 64 * K; 772 773 // amd64: pthread on amd64 is always in floating stack mode 774 bool os::Bsd::supports_variable_stack_size() { return true; } 775 #else 776 size_t os::Bsd::min_stack_allowed = (48 DEBUG_ONLY(+4))*K; 777 778 #ifdef __GNUC__ 779 #define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;}) 780 #endif 781 782 bool os::Bsd::supports_variable_stack_size() { return true; } 783 #endif // AMD64 784 785 // return default stack size for thr_type 786 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) { 787 // default stack size (compiler thread needs larger stack) 788 #ifdef AMD64 789 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M); 790 #else 791 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K); 792 #endif // AMD64 793 return s; 794 } 795 796 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) { 797 // Creating guard page is very expensive. Java thread has HotSpot 798 // guard page, only enable glibc guard page for non-Java threads. 799 return (thr_type == java_thread ? 0 : page_size()); 800 } 801 802 // Java thread: 803 // 804 // Low memory addresses 805 // +------------------------+ 806 // | |\ JavaThread created by VM does not have glibc 807 // | glibc guard page | - guard, attached Java thread usually has 808 // | |/ 1 page glibc guard. 809 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 810 // | |\ 811 // | HotSpot Guard Pages | - red and yellow pages 812 // | |/ 813 // +------------------------+ JavaThread::stack_yellow_zone_base() 814 // | |\ 815 // | Normal Stack | - 816 // | |/ 817 // P2 +------------------------+ Thread::stack_base() 818 // 819 // Non-Java thread: 820 // 821 // Low memory addresses 822 // +------------------------+ 823 // | |\ 824 // | glibc guard page | - usually 1 page 825 // | |/ 826 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 827 // | |\ 828 // | Normal Stack | - 829 // | |/ 830 // P2 +------------------------+ Thread::stack_base() 831 // 832 // ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from 833 // pthread_attr_getstack() 834 835 static void current_stack_region(address * bottom, size_t * size) { 836 #ifdef __APPLE__ 837 pthread_t self = pthread_self(); 838 void *stacktop = pthread_get_stackaddr_np(self); 839 *size = pthread_get_stacksize_np(self); 840 // workaround for OS X 10.9.0 (Mavericks) 841 // pthread_get_stacksize_np returns 128 pages even though the actual size is 2048 pages 842 if (pthread_main_np() == 1) { 843 if ((*size) < (DEFAULT_MAIN_THREAD_STACK_PAGES * (size_t)getpagesize())) { 844 char kern_osrelease[256]; 845 size_t kern_osrelease_size = sizeof(kern_osrelease); 846 int ret = sysctlbyname("kern.osrelease", kern_osrelease, &kern_osrelease_size, NULL, 0); 847 if (ret == 0) { 848 // get the major number, atoi will ignore the minor amd micro portions of the version string 849 if (atoi(kern_osrelease) >= OS_X_10_9_0_KERNEL_MAJOR_VERSION) { 850 *size = (DEFAULT_MAIN_THREAD_STACK_PAGES*getpagesize()); 851 } 852 } 853 } 854 } 855 *bottom = (address) stacktop - *size; 856 #elif defined(__OpenBSD__) 857 stack_t ss; 858 int rslt = pthread_stackseg_np(pthread_self(), &ss); 859 860 if (rslt != 0) 861 fatal(err_msg("pthread_stackseg_np failed with err = %d", rslt)); 862 863 *bottom = (address)((char *)ss.ss_sp - ss.ss_size); 864 *size = ss.ss_size; 865 #else 866 pthread_attr_t attr; 867 868 int rslt = pthread_attr_init(&attr); 869 870 // JVM needs to know exact stack location, abort if it fails 871 if (rslt != 0) 872 fatal(err_msg("pthread_attr_init failed with err = %d", rslt)); 873 874 rslt = pthread_attr_get_np(pthread_self(), &attr); 875 876 if (rslt != 0) 877 fatal(err_msg("pthread_attr_get_np failed with err = %d", rslt)); 878 879 if (pthread_attr_getstackaddr(&attr, (void **)bottom) != 0 || 880 pthread_attr_getstacksize(&attr, size) != 0) { 881 fatal("Can not locate current stack attributes!"); 882 } 883 884 pthread_attr_destroy(&attr); 885 #endif 886 assert(os::current_stack_pointer() >= *bottom && 887 os::current_stack_pointer() < *bottom + *size, "just checking"); 888 } 889 890 address os::current_stack_base() { 891 address bottom; 892 size_t size; 893 current_stack_region(&bottom, &size); 894 return (bottom + size); 895 } 896 897 size_t os::current_stack_size() { 898 // stack size includes normal stack and HotSpot guard pages 899 address bottom; 900 size_t size; 901 current_stack_region(&bottom, &size); 902 return size; 903 } 904 905 ///////////////////////////////////////////////////////////////////////////// 906 // helper functions for fatal error handler 907 908 void os::print_context(outputStream *st, void *context) { 909 if (context == NULL) return; 910 911 ucontext_t *uc = (ucontext_t*)context; 912 st->print_cr("Registers:"); 913 #ifdef AMD64 914 st->print( "RAX=" INTPTR_FORMAT, uc->context_rax); 915 st->print(", RBX=" INTPTR_FORMAT, uc->context_rbx); 916 st->print(", RCX=" INTPTR_FORMAT, uc->context_rcx); 917 st->print(", RDX=" INTPTR_FORMAT, uc->context_rdx); 918 st->cr(); 919 st->print( "RSP=" INTPTR_FORMAT, uc->context_rsp); 920 st->print(", RBP=" INTPTR_FORMAT, uc->context_rbp); 921 st->print(", RSI=" INTPTR_FORMAT, uc->context_rsi); 922 st->print(", RDI=" INTPTR_FORMAT, uc->context_rdi); 923 st->cr(); 924 st->print( "R8 =" INTPTR_FORMAT, uc->context_r8); 925 st->print(", R9 =" INTPTR_FORMAT, uc->context_r9); 926 st->print(", R10=" INTPTR_FORMAT, uc->context_r10); 927 st->print(", R11=" INTPTR_FORMAT, uc->context_r11); 928 st->cr(); 929 st->print( "R12=" INTPTR_FORMAT, uc->context_r12); 930 st->print(", R13=" INTPTR_FORMAT, uc->context_r13); 931 st->print(", R14=" INTPTR_FORMAT, uc->context_r14); 932 st->print(", R15=" INTPTR_FORMAT, uc->context_r15); 933 st->cr(); 934 st->print( "RIP=" INTPTR_FORMAT, uc->context_rip); 935 st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_flags); 936 st->print(", ERR=" INTPTR_FORMAT, uc->context_err); 937 st->cr(); 938 st->print(" TRAPNO=" INTPTR_FORMAT, uc->context_trapno); 939 #else 940 st->print( "EAX=" INTPTR_FORMAT, uc->context_eax); 941 st->print(", EBX=" INTPTR_FORMAT, uc->context_ebx); 942 st->print(", ECX=" INTPTR_FORMAT, uc->context_ecx); 943 st->print(", EDX=" INTPTR_FORMAT, uc->context_edx); 944 st->cr(); 945 st->print( "ESP=" INTPTR_FORMAT, uc->context_esp); 946 st->print(", EBP=" INTPTR_FORMAT, uc->context_ebp); 947 st->print(", ESI=" INTPTR_FORMAT, uc->context_esi); 948 st->print(", EDI=" INTPTR_FORMAT, uc->context_edi); 949 st->cr(); 950 st->print( "EIP=" INTPTR_FORMAT, uc->context_eip); 951 st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_eflags); 952 #endif // AMD64 953 st->cr(); 954 st->cr(); 955 956 intptr_t *sp = (intptr_t *)os::Bsd::ucontext_get_sp(uc); 957 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 958 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 959 st->cr(); 960 961 // Note: it may be unsafe to inspect memory near pc. For example, pc may 962 // point to garbage if entry point in an nmethod is corrupted. Leave 963 // this at the end, and hope for the best. 964 address pc = os::Bsd::ucontext_get_pc(uc); 965 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 966 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 967 } 968 969 void os::print_register_info(outputStream *st, void *context) { 970 if (context == NULL) return; 971 972 ucontext_t *uc = (ucontext_t*)context; 973 974 st->print_cr("Register to memory mapping:"); 975 st->cr(); 976 977 // this is horrendously verbose but the layout of the registers in the 978 // context does not match how we defined our abstract Register set, so 979 // we can't just iterate through the gregs area 980 981 // this is only for the "general purpose" registers 982 983 #ifdef AMD64 984 st->print("RAX="); print_location(st, uc->context_rax); 985 st->print("RBX="); print_location(st, uc->context_rbx); 986 st->print("RCX="); print_location(st, uc->context_rcx); 987 st->print("RDX="); print_location(st, uc->context_rdx); 988 st->print("RSP="); print_location(st, uc->context_rsp); 989 st->print("RBP="); print_location(st, uc->context_rbp); 990 st->print("RSI="); print_location(st, uc->context_rsi); 991 st->print("RDI="); print_location(st, uc->context_rdi); 992 st->print("R8 ="); print_location(st, uc->context_r8); 993 st->print("R9 ="); print_location(st, uc->context_r9); 994 st->print("R10="); print_location(st, uc->context_r10); 995 st->print("R11="); print_location(st, uc->context_r11); 996 st->print("R12="); print_location(st, uc->context_r12); 997 st->print("R13="); print_location(st, uc->context_r13); 998 st->print("R14="); print_location(st, uc->context_r14); 999 st->print("R15="); print_location(st, uc->context_r15); 1000 #else 1001 st->print("EAX="); print_location(st, uc->context_eax); 1002 st->print("EBX="); print_location(st, uc->context_ebx); 1003 st->print("ECX="); print_location(st, uc->context_ecx); 1004 st->print("EDX="); print_location(st, uc->context_edx); 1005 st->print("ESP="); print_location(st, uc->context_esp); 1006 st->print("EBP="); print_location(st, uc->context_ebp); 1007 st->print("ESI="); print_location(st, uc->context_esi); 1008 st->print("EDI="); print_location(st, uc->context_edi); 1009 #endif // AMD64 1010 1011 st->cr(); 1012 } 1013 1014 void os::setup_fpu() { 1015 #ifndef AMD64 1016 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 1017 __asm__ volatile ( "fldcw (%0)" : 1018 : "r" (fpu_cntrl) : "memory"); 1019 #endif // !AMD64 1020 } 1021 1022 #ifndef PRODUCT 1023 void os::verify_stack_alignment() { 1024 } 1025 #endif