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 if ((sig == SIGSEGV || sig == SIGBUS) && VM_Version::is_cpuinfo_segv_addr(pc)) { 496 // Verify that OS save/restore AVX registers. 497 stub = VM_Version::cpuinfo_cont_addr(); 498 } 499 500 // We test if stub is already set (by the stack overflow code 501 // above) so it is not overwritten by the code that follows. This 502 // check is not required on other platforms, because on other 503 // platforms we check for SIGSEGV only or SIGBUS only, where here 504 // we have to check for both SIGSEGV and SIGBUS. 505 if (thread->thread_state() == _thread_in_Java && stub == NULL) { 506 // Java thread running in Java code => find exception handler if any 507 // a fault inside compiled code, the interpreter, or a stub 508 509 if ((sig == SIGSEGV || sig == SIGBUS) && os::is_poll_address((address)info->si_addr)) { 510 stub = SharedRuntime::get_poll_stub(pc); 511 #if defined(__APPLE__) 512 // 32-bit Darwin reports a SIGBUS for nearly all memory access exceptions. 513 // 64-bit Darwin may also use a SIGBUS (seen with compressed oops). 514 // Catching SIGBUS here prevents the implicit SIGBUS NULL check below from 515 // being called, so only do so if the implicit NULL check is not necessary. 516 } else if (sig == SIGBUS && MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 517 #else 518 } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) { 519 #endif 520 // BugId 4454115: A read from a MappedByteBuffer can fault 521 // here if the underlying file has been truncated. 522 // Do not crash the VM in such a case. 523 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 524 nmethod* nm = (cb != NULL && cb->is_nmethod()) ? (nmethod*)cb : NULL; 525 if (nm != NULL && nm->has_unsafe_access()) { 526 stub = StubRoutines::handler_for_unsafe_access(); 527 } 528 } 529 else 530 531 #ifdef AMD64 532 if (sig == SIGFPE && 533 (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) { 534 stub = 535 SharedRuntime:: 536 continuation_for_implicit_exception(thread, 537 pc, 538 SharedRuntime:: 539 IMPLICIT_DIVIDE_BY_ZERO); 540 #ifdef __APPLE__ 541 } else if (sig == SIGFPE && info->si_code == FPE_NOOP) { 542 int op = pc[0]; 543 544 // Skip REX 545 if ((pc[0] & 0xf0) == 0x40) { 546 op = pc[1]; 547 } else { 548 op = pc[0]; 549 } 550 551 // Check for IDIV 552 if (op == 0xF7) { 553 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime:: IMPLICIT_DIVIDE_BY_ZERO); 554 } else { 555 // TODO: handle more cases if we are using other x86 instructions 556 // that can generate SIGFPE signal. 557 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); 558 fatal("please update this code."); 559 } 560 #endif /* __APPLE__ */ 561 562 #else 563 if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) { 564 // HACK: si_code does not work on bsd 2.2.12-20!!! 565 int op = pc[0]; 566 if (op == 0xDB) { 567 // FIST 568 // TODO: The encoding of D2I in i486.ad can cause an exception 569 // prior to the fist instruction if there was an invalid operation 570 // pending. We want to dismiss that exception. From the win_32 571 // side it also seems that if it really was the fist causing 572 // the exception that we do the d2i by hand with different 573 // rounding. Seems kind of weird. 574 // NOTE: that we take the exception at the NEXT floating point instruction. 575 assert(pc[0] == 0xDB, "not a FIST opcode"); 576 assert(pc[1] == 0x14, "not a FIST opcode"); 577 assert(pc[2] == 0x24, "not a FIST opcode"); 578 return true; 579 } else if (op == 0xF7) { 580 // IDIV 581 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 582 } else { 583 // TODO: handle more cases if we are using other x86 instructions 584 // that can generate SIGFPE signal on bsd. 585 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); 586 fatal("please update this code."); 587 } 588 #endif // AMD64 589 } else if ((sig == SIGSEGV || sig == SIGBUS) && 590 !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 591 // Determination of interpreter/vtable stub/compiled code null exception 592 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 593 } 594 } else if (thread->thread_state() == _thread_in_vm && 595 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */ 596 thread->doing_unsafe_access()) { 597 stub = StubRoutines::handler_for_unsafe_access(); 598 } 599 600 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 601 // and the heap gets shrunk before the field access. 602 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 603 address addr = JNI_FastGetField::find_slowcase_pc(pc); 604 if (addr != (address)-1) { 605 stub = addr; 606 } 607 } 608 609 // Check to see if we caught the safepoint code in the 610 // process of write protecting the memory serialization page. 611 // It write enables the page immediately after protecting it 612 // so we can just return to retry the write. 613 if ((sig == SIGSEGV || sig == SIGBUS) && 614 os::is_memory_serialize_page(thread, (address) info->si_addr)) { 615 // Block current thread until the memory serialize page permission restored. 616 os::block_on_serialize_page_trap(); 617 return true; 618 } 619 } 620 621 #ifndef AMD64 622 // Execution protection violation 623 // 624 // This should be kept as the last step in the triage. We don't 625 // have a dedicated trap number for a no-execute fault, so be 626 // conservative and allow other handlers the first shot. 627 // 628 // Note: We don't test that info->si_code == SEGV_ACCERR here. 629 // this si_code is so generic that it is almost meaningless; and 630 // the si_code for this condition may change in the future. 631 // Furthermore, a false-positive should be harmless. 632 if (UnguardOnExecutionViolation > 0 && 633 (sig == SIGSEGV || sig == SIGBUS) && 634 uc->context_trapno == trap_page_fault) { 635 int page_size = os::vm_page_size(); 636 address addr = (address) info->si_addr; 637 address pc = os::Bsd::ucontext_get_pc(uc); 638 // Make sure the pc and the faulting address are sane. 639 // 640 // If an instruction spans a page boundary, and the page containing 641 // the beginning of the instruction is executable but the following 642 // page is not, the pc and the faulting address might be slightly 643 // different - we still want to unguard the 2nd page in this case. 644 // 645 // 15 bytes seems to be a (very) safe value for max instruction size. 646 bool pc_is_near_addr = 647 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 648 bool instr_spans_page_boundary = 649 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 650 (intptr_t) page_size) > 0); 651 652 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 653 static volatile address last_addr = 654 (address) os::non_memory_address_word(); 655 656 // In conservative mode, don't unguard unless the address is in the VM 657 if (addr != last_addr && 658 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 659 660 // Set memory to RWX and retry 661 address page_start = 662 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 663 bool res = os::protect_memory((char*) page_start, page_size, 664 os::MEM_PROT_RWX); 665 666 if (PrintMiscellaneous && Verbose) { 667 char buf[256]; 668 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 669 "at " INTPTR_FORMAT 670 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 671 page_start, (res ? "success" : "failed"), errno); 672 tty->print_raw_cr(buf); 673 } 674 stub = pc; 675 676 // Set last_addr so if we fault again at the same address, we don't end 677 // up in an endless loop. 678 // 679 // There are two potential complications here. Two threads trapping at 680 // the same address at the same time could cause one of the threads to 681 // think it already unguarded, and abort the VM. Likely very rare. 682 // 683 // The other race involves two threads alternately trapping at 684 // different addresses and failing to unguard the page, resulting in 685 // an endless loop. This condition is probably even more unlikely than 686 // the first. 687 // 688 // Although both cases could be avoided by using locks or thread local 689 // last_addr, these solutions are unnecessary complication: this 690 // handler is a best-effort safety net, not a complete solution. It is 691 // disabled by default and should only be used as a workaround in case 692 // we missed any no-execute-unsafe VM code. 693 694 last_addr = addr; 695 } 696 } 697 } 698 #endif // !AMD64 699 700 if (stub != NULL) { 701 // save all thread context in case we need to restore it 702 if (thread != NULL) thread->set_saved_exception_pc(pc); 703 704 uc->context_pc = (intptr_t)stub; 705 return true; 706 } 707 708 // signal-chaining 709 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 710 return true; 711 } 712 713 if (!abort_if_unrecognized) { 714 // caller wants another chance, so give it to him 715 return false; 716 } 717 718 if (pc == NULL && uc != NULL) { 719 pc = os::Bsd::ucontext_get_pc(uc); 720 } 721 722 // unmask current signal 723 sigset_t newset; 724 sigemptyset(&newset); 725 sigaddset(&newset, sig); 726 sigprocmask(SIG_UNBLOCK, &newset, NULL); 727 728 VMError err(t, sig, pc, info, ucVoid); 729 err.report_and_die(); 730 731 ShouldNotReachHere(); 732 return false; 733 } 734 735 // From solaris_i486.s ported to bsd_i486.s 736 extern "C" void fixcw(); 737 738 void os::Bsd::init_thread_fpu_state(void) { 739 #ifndef AMD64 740 // Set fpu to 53 bit precision. This happens too early to use a stub. 741 fixcw(); 742 #endif // !AMD64 743 } 744 745 746 // Check that the bsd kernel version is 2.4 or higher since earlier 747 // versions do not support SSE without patches. 748 bool os::supports_sse() { 749 return true; 750 } 751 752 bool os::is_allocatable(size_t bytes) { 753 #ifdef AMD64 754 // unused on amd64? 755 return true; 756 #else 757 758 if (bytes < 2 * G) { 759 return true; 760 } 761 762 char* addr = reserve_memory(bytes, NULL); 763 764 if (addr != NULL) { 765 release_memory(addr, bytes); 766 } 767 768 return addr != NULL; 769 #endif // AMD64 770 } 771 772 //////////////////////////////////////////////////////////////////////////////// 773 // thread stack 774 775 #ifdef AMD64 776 size_t os::Bsd::min_stack_allowed = 64 * K; 777 778 // amd64: pthread on amd64 is always in floating stack mode 779 bool os::Bsd::supports_variable_stack_size() { return true; } 780 #else 781 size_t os::Bsd::min_stack_allowed = (48 DEBUG_ONLY(+4))*K; 782 783 #ifdef __GNUC__ 784 #define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;}) 785 #endif 786 787 bool os::Bsd::supports_variable_stack_size() { return true; } 788 #endif // AMD64 789 790 // return default stack size for thr_type 791 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) { 792 // default stack size (compiler thread needs larger stack) 793 #ifdef AMD64 794 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M); 795 #else 796 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K); 797 #endif // AMD64 798 return s; 799 } 800 801 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) { 802 // Creating guard page is very expensive. Java thread has HotSpot 803 // guard page, only enable glibc guard page for non-Java threads. 804 return (thr_type == java_thread ? 0 : page_size()); 805 } 806 807 // Java thread: 808 // 809 // Low memory addresses 810 // +------------------------+ 811 // | |\ JavaThread created by VM does not have glibc 812 // | glibc guard page | - guard, attached Java thread usually has 813 // | |/ 1 page glibc guard. 814 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 815 // | |\ 816 // | HotSpot Guard Pages | - red and yellow pages 817 // | |/ 818 // +------------------------+ JavaThread::stack_yellow_zone_base() 819 // | |\ 820 // | Normal Stack | - 821 // | |/ 822 // P2 +------------------------+ Thread::stack_base() 823 // 824 // Non-Java thread: 825 // 826 // Low memory addresses 827 // +------------------------+ 828 // | |\ 829 // | glibc guard page | - usually 1 page 830 // | |/ 831 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 832 // | |\ 833 // | Normal Stack | - 834 // | |/ 835 // P2 +------------------------+ Thread::stack_base() 836 // 837 // ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from 838 // pthread_attr_getstack() 839 840 static void current_stack_region(address * bottom, size_t * size) { 841 #ifdef __APPLE__ 842 pthread_t self = pthread_self(); 843 void *stacktop = pthread_get_stackaddr_np(self); 844 *size = pthread_get_stacksize_np(self); 845 // workaround for OS X 10.9.0 (Mavericks) 846 // pthread_get_stacksize_np returns 128 pages even though the actual size is 2048 pages 847 if (pthread_main_np() == 1) { 848 if ((*size) < (DEFAULT_MAIN_THREAD_STACK_PAGES * (size_t)getpagesize())) { 849 char kern_osrelease[256]; 850 size_t kern_osrelease_size = sizeof(kern_osrelease); 851 int ret = sysctlbyname("kern.osrelease", kern_osrelease, &kern_osrelease_size, NULL, 0); 852 if (ret == 0) { 853 // get the major number, atoi will ignore the minor amd micro portions of the version string 854 if (atoi(kern_osrelease) >= OS_X_10_9_0_KERNEL_MAJOR_VERSION) { 855 *size = (DEFAULT_MAIN_THREAD_STACK_PAGES*getpagesize()); 856 } 857 } 858 } 859 } 860 *bottom = (address) stacktop - *size; 861 #elif defined(__OpenBSD__) 862 stack_t ss; 863 int rslt = pthread_stackseg_np(pthread_self(), &ss); 864 865 if (rslt != 0) 866 fatal(err_msg("pthread_stackseg_np failed with err = %d", rslt)); 867 868 *bottom = (address)((char *)ss.ss_sp - ss.ss_size); 869 *size = ss.ss_size; 870 #else 871 pthread_attr_t attr; 872 873 int rslt = pthread_attr_init(&attr); 874 875 // JVM needs to know exact stack location, abort if it fails 876 if (rslt != 0) 877 fatal(err_msg("pthread_attr_init failed with err = %d", rslt)); 878 879 rslt = pthread_attr_get_np(pthread_self(), &attr); 880 881 if (rslt != 0) 882 fatal(err_msg("pthread_attr_get_np failed with err = %d", rslt)); 883 884 if (pthread_attr_getstackaddr(&attr, (void **)bottom) != 0 || 885 pthread_attr_getstacksize(&attr, size) != 0) { 886 fatal("Can not locate current stack attributes!"); 887 } 888 889 pthread_attr_destroy(&attr); 890 #endif 891 assert(os::current_stack_pointer() >= *bottom && 892 os::current_stack_pointer() < *bottom + *size, "just checking"); 893 } 894 895 address os::current_stack_base() { 896 address bottom; 897 size_t size; 898 current_stack_region(&bottom, &size); 899 return (bottom + size); 900 } 901 902 size_t os::current_stack_size() { 903 // stack size includes normal stack and HotSpot guard pages 904 address bottom; 905 size_t size; 906 current_stack_region(&bottom, &size); 907 return size; 908 } 909 910 ///////////////////////////////////////////////////////////////////////////// 911 // helper functions for fatal error handler 912 913 void os::print_context(outputStream *st, void *context) { 914 if (context == NULL) return; 915 916 ucontext_t *uc = (ucontext_t*)context; 917 st->print_cr("Registers:"); 918 #ifdef AMD64 919 st->print( "RAX=" INTPTR_FORMAT, uc->context_rax); 920 st->print(", RBX=" INTPTR_FORMAT, uc->context_rbx); 921 st->print(", RCX=" INTPTR_FORMAT, uc->context_rcx); 922 st->print(", RDX=" INTPTR_FORMAT, uc->context_rdx); 923 st->cr(); 924 st->print( "RSP=" INTPTR_FORMAT, uc->context_rsp); 925 st->print(", RBP=" INTPTR_FORMAT, uc->context_rbp); 926 st->print(", RSI=" INTPTR_FORMAT, uc->context_rsi); 927 st->print(", RDI=" INTPTR_FORMAT, uc->context_rdi); 928 st->cr(); 929 st->print( "R8 =" INTPTR_FORMAT, uc->context_r8); 930 st->print(", R9 =" INTPTR_FORMAT, uc->context_r9); 931 st->print(", R10=" INTPTR_FORMAT, uc->context_r10); 932 st->print(", R11=" INTPTR_FORMAT, uc->context_r11); 933 st->cr(); 934 st->print( "R12=" INTPTR_FORMAT, uc->context_r12); 935 st->print(", R13=" INTPTR_FORMAT, uc->context_r13); 936 st->print(", R14=" INTPTR_FORMAT, uc->context_r14); 937 st->print(", R15=" INTPTR_FORMAT, uc->context_r15); 938 st->cr(); 939 st->print( "RIP=" INTPTR_FORMAT, uc->context_rip); 940 st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_flags); 941 st->print(", ERR=" INTPTR_FORMAT, uc->context_err); 942 st->cr(); 943 st->print(" TRAPNO=" INTPTR_FORMAT, uc->context_trapno); 944 #else 945 st->print( "EAX=" INTPTR_FORMAT, uc->context_eax); 946 st->print(", EBX=" INTPTR_FORMAT, uc->context_ebx); 947 st->print(", ECX=" INTPTR_FORMAT, uc->context_ecx); 948 st->print(", EDX=" INTPTR_FORMAT, uc->context_edx); 949 st->cr(); 950 st->print( "ESP=" INTPTR_FORMAT, uc->context_esp); 951 st->print(", EBP=" INTPTR_FORMAT, uc->context_ebp); 952 st->print(", ESI=" INTPTR_FORMAT, uc->context_esi); 953 st->print(", EDI=" INTPTR_FORMAT, uc->context_edi); 954 st->cr(); 955 st->print( "EIP=" INTPTR_FORMAT, uc->context_eip); 956 st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_eflags); 957 #endif // AMD64 958 st->cr(); 959 st->cr(); 960 961 intptr_t *sp = (intptr_t *)os::Bsd::ucontext_get_sp(uc); 962 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 963 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 964 st->cr(); 965 966 // Note: it may be unsafe to inspect memory near pc. For example, pc may 967 // point to garbage if entry point in an nmethod is corrupted. Leave 968 // this at the end, and hope for the best. 969 address pc = os::Bsd::ucontext_get_pc(uc); 970 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 971 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 972 } 973 974 void os::print_register_info(outputStream *st, void *context) { 975 if (context == NULL) return; 976 977 ucontext_t *uc = (ucontext_t*)context; 978 979 st->print_cr("Register to memory mapping:"); 980 st->cr(); 981 982 // this is horrendously verbose but the layout of the registers in the 983 // context does not match how we defined our abstract Register set, so 984 // we can't just iterate through the gregs area 985 986 // this is only for the "general purpose" registers 987 988 #ifdef AMD64 989 st->print("RAX="); print_location(st, uc->context_rax); 990 st->print("RBX="); print_location(st, uc->context_rbx); 991 st->print("RCX="); print_location(st, uc->context_rcx); 992 st->print("RDX="); print_location(st, uc->context_rdx); 993 st->print("RSP="); print_location(st, uc->context_rsp); 994 st->print("RBP="); print_location(st, uc->context_rbp); 995 st->print("RSI="); print_location(st, uc->context_rsi); 996 st->print("RDI="); print_location(st, uc->context_rdi); 997 st->print("R8 ="); print_location(st, uc->context_r8); 998 st->print("R9 ="); print_location(st, uc->context_r9); 999 st->print("R10="); print_location(st, uc->context_r10); 1000 st->print("R11="); print_location(st, uc->context_r11); 1001 st->print("R12="); print_location(st, uc->context_r12); 1002 st->print("R13="); print_location(st, uc->context_r13); 1003 st->print("R14="); print_location(st, uc->context_r14); 1004 st->print("R15="); print_location(st, uc->context_r15); 1005 #else 1006 st->print("EAX="); print_location(st, uc->context_eax); 1007 st->print("EBX="); print_location(st, uc->context_ebx); 1008 st->print("ECX="); print_location(st, uc->context_ecx); 1009 st->print("EDX="); print_location(st, uc->context_edx); 1010 st->print("ESP="); print_location(st, uc->context_esp); 1011 st->print("EBP="); print_location(st, uc->context_ebp); 1012 st->print("ESI="); print_location(st, uc->context_esi); 1013 st->print("EDI="); print_location(st, uc->context_edi); 1014 #endif // AMD64 1015 1016 st->cr(); 1017 } 1018 1019 void os::setup_fpu() { 1020 #ifndef AMD64 1021 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 1022 __asm__ volatile ( "fldcw (%0)" : 1023 : "r" (fpu_cntrl) : "memory"); 1024 #endif // !AMD64 1025 } 1026 1027 #ifndef PRODUCT 1028 void os::verify_stack_alignment() { 1029 } 1030 #endif