os_bsd_x86.cpp revision 6412:53a41e7cbe05
1/* 2 * Copyright (c) 1999, 2014, 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 279PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 280 281address os::current_stack_pointer() { 282#if defined(__clang__) || defined(__llvm__) 283 register void *esp; 284 __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp)); 285 return (address) esp; 286#elif defined(SPARC_WORKS) 287 register void *esp; 288 __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp)); 289 return (address) ((char*)esp + sizeof(long)*2); 290#else 291 register void *esp __asm__ (SPELL_REG_SP); 292 return (address) esp; 293#endif 294} 295 296char* os::non_memory_address_word() { 297 // Must never look like an address returned by reserve_memory, 298 // even in its subfields (as defined by the CPU immediate fields, 299 // if the CPU splits constants across multiple instructions). 300 301 return (char*) -1; 302} 303 304void os::initialize_thread(Thread* thr) { 305// Nothing to do. 306} 307 308address os::Bsd::ucontext_get_pc(ucontext_t * uc) { 309 return (address)uc->context_pc; 310} 311 312intptr_t* os::Bsd::ucontext_get_sp(ucontext_t * uc) { 313 return (intptr_t*)uc->context_sp; 314} 315 316intptr_t* os::Bsd::ucontext_get_fp(ucontext_t * uc) { 317 return (intptr_t*)uc->context_fp; 318} 319 320// For Forte Analyzer AsyncGetCallTrace profiling support - thread 321// is currently interrupted by SIGPROF. 322// os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal 323// frames. Currently we don't do that on Bsd, so it's the same as 324// os::fetch_frame_from_context(). 325ExtendedPC os::Bsd::fetch_frame_from_ucontext(Thread* thread, 326 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 327 328 assert(thread != NULL, "just checking"); 329 assert(ret_sp != NULL, "just checking"); 330 assert(ret_fp != NULL, "just checking"); 331 332 return os::fetch_frame_from_context(uc, ret_sp, ret_fp); 333} 334 335ExtendedPC os::fetch_frame_from_context(void* ucVoid, 336 intptr_t** ret_sp, intptr_t** ret_fp) { 337 338 ExtendedPC epc; 339 ucontext_t* uc = (ucontext_t*)ucVoid; 340 341 if (uc != NULL) { 342 epc = ExtendedPC(os::Bsd::ucontext_get_pc(uc)); 343 if (ret_sp) *ret_sp = os::Bsd::ucontext_get_sp(uc); 344 if (ret_fp) *ret_fp = os::Bsd::ucontext_get_fp(uc); 345 } else { 346 // construct empty ExtendedPC for return value checking 347 epc = ExtendedPC(NULL); 348 if (ret_sp) *ret_sp = (intptr_t *)NULL; 349 if (ret_fp) *ret_fp = (intptr_t *)NULL; 350 } 351 352 return epc; 353} 354 355frame os::fetch_frame_from_context(void* ucVoid) { 356 intptr_t* sp; 357 intptr_t* fp; 358 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 359 return frame(sp, fp, epc.pc()); 360} 361 362// By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get 363// turned off by -fomit-frame-pointer, 364frame os::get_sender_for_C_frame(frame* fr) { 365 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 366} 367 368intptr_t* _get_previous_fp() { 369#if defined(SPARC_WORKS) || defined(__clang__) || defined(__llvm__) 370 register intptr_t **ebp; 371 __asm__("mov %%"SPELL_REG_FP", %0":"=r"(ebp)); 372#else 373 register intptr_t **ebp __asm__ (SPELL_REG_FP); 374#endif 375 return (intptr_t*) *ebp; // we want what it points to. 376} 377 378 379frame os::current_frame() { 380 intptr_t* fp = _get_previous_fp(); 381 frame myframe((intptr_t*)os::current_stack_pointer(), 382 (intptr_t*)fp, 383 CAST_FROM_FN_PTR(address, os::current_frame)); 384 if (os::is_first_C_frame(&myframe)) { 385 // stack is not walkable 386 return frame(); 387 } else { 388 return os::get_sender_for_C_frame(&myframe); 389 } 390} 391 392// Utility functions 393 394// From IA32 System Programming Guide 395enum { 396 trap_page_fault = 0xE 397}; 398 399extern "C" JNIEXPORT int 400JVM_handle_bsd_signal(int sig, 401 siginfo_t* info, 402 void* ucVoid, 403 int abort_if_unrecognized) { 404 ucontext_t* uc = (ucontext_t*) ucVoid; 405 406 Thread* t = ThreadLocalStorage::get_thread_slow(); 407 408 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away 409 // (no destructors can be run) 410 os::WatcherThreadCrashProtection::check_crash_protection(sig, t); 411 412 SignalHandlerMark shm(t); 413 414 // Note: it's not uncommon that JNI code uses signal/sigset to install 415 // then restore certain signal handler (e.g. to temporarily block SIGPIPE, 416 // or have a SIGILL handler when detecting CPU type). When that happens, 417 // JVM_handle_bsd_signal() might be invoked with junk info/ucVoid. To 418 // avoid unnecessary crash when libjsig is not preloaded, try handle signals 419 // that do not require siginfo/ucontext first. 420 421 if (sig == SIGPIPE || sig == SIGXFSZ) { 422 // allow chained handler to go first 423 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 424 return true; 425 } else { 426 if (PrintMiscellaneous && (WizardMode || Verbose)) { 427 char buf[64]; 428 warning("Ignoring %s - see bugs 4229104 or 646499219", 429 os::exception_name(sig, buf, sizeof(buf))); 430 } 431 return true; 432 } 433 } 434 435 JavaThread* thread = NULL; 436 VMThread* vmthread = NULL; 437 if (os::Bsd::signal_handlers_are_installed) { 438 if (t != NULL ){ 439 if(t->is_Java_thread()) { 440 thread = (JavaThread*)t; 441 } 442 else if(t->is_VM_thread()){ 443 vmthread = (VMThread *)t; 444 } 445 } 446 } 447/* 448 NOTE: does not seem to work on bsd. 449 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 450 // can't decode this kind of signal 451 info = NULL; 452 } else { 453 assert(sig == info->si_signo, "bad siginfo"); 454 } 455*/ 456 // decide if this trap can be handled by a stub 457 address stub = NULL; 458 459 address pc = NULL; 460 461 //%note os_trap_1 462 if (info != NULL && uc != NULL && thread != NULL) { 463 pc = (address) os::Bsd::ucontext_get_pc(uc); 464 465 if (StubRoutines::is_safefetch_fault(pc)) { 466 uc->context_pc = intptr_t(StubRoutines::continuation_for_safefetch_fault(pc)); 467 return 1; 468 } 469 470 // Handle ALL stack overflow variations here 471 if (sig == SIGSEGV || sig == SIGBUS) { 472 address addr = (address) info->si_addr; 473 474 // check if fault address is within thread stack 475 if (addr < thread->stack_base() && 476 addr >= thread->stack_base() - thread->stack_size()) { 477 // stack overflow 478 if (thread->in_stack_yellow_zone(addr)) { 479 thread->disable_stack_yellow_zone(); 480 if (thread->thread_state() == _thread_in_Java) { 481 // Throw a stack overflow exception. Guard pages will be reenabled 482 // while unwinding the stack. 483 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 484 } else { 485 // Thread was in the vm or native code. Return and try to finish. 486 return 1; 487 } 488 } else if (thread->in_stack_red_zone(addr)) { 489 // Fatal red zone violation. Disable the guard pages and fall through 490 // to handle_unexpected_exception way down below. 491 thread->disable_stack_red_zone(); 492 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 493 } 494 } 495 } 496 497 if ((sig == SIGSEGV || sig == SIGBUS) && VM_Version::is_cpuinfo_segv_addr(pc)) { 498 // Verify that OS save/restore AVX registers. 499 stub = VM_Version::cpuinfo_cont_addr(); 500 } 501 502 // We test if stub is already set (by the stack overflow code 503 // above) so it is not overwritten by the code that follows. This 504 // check is not required on other platforms, because on other 505 // platforms we check for SIGSEGV only or SIGBUS only, where here 506 // we have to check for both SIGSEGV and SIGBUS. 507 if (thread->thread_state() == _thread_in_Java && stub == NULL) { 508 // Java thread running in Java code => find exception handler if any 509 // a fault inside compiled code, the interpreter, or a stub 510 511 if ((sig == SIGSEGV || sig == SIGBUS) && os::is_poll_address((address)info->si_addr)) { 512 stub = SharedRuntime::get_poll_stub(pc); 513#if defined(__APPLE__) 514 // 32-bit Darwin reports a SIGBUS for nearly all memory access exceptions. 515 // 64-bit Darwin may also use a SIGBUS (seen with compressed oops). 516 // Catching SIGBUS here prevents the implicit SIGBUS NULL check below from 517 // being called, so only do so if the implicit NULL check is not necessary. 518 } else if (sig == SIGBUS && MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 519#else 520 } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) { 521#endif 522 // BugId 4454115: A read from a MappedByteBuffer can fault 523 // here if the underlying file has been truncated. 524 // Do not crash the VM in such a case. 525 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 526 nmethod* nm = (cb != NULL && cb->is_nmethod()) ? (nmethod*)cb : NULL; 527 if (nm != NULL && nm->has_unsafe_access()) { 528 stub = StubRoutines::handler_for_unsafe_access(); 529 } 530 } 531 else 532 533#ifdef AMD64 534 if (sig == SIGFPE && 535 (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) { 536 stub = 537 SharedRuntime:: 538 continuation_for_implicit_exception(thread, 539 pc, 540 SharedRuntime:: 541 IMPLICIT_DIVIDE_BY_ZERO); 542#ifdef __APPLE__ 543 } else if (sig == SIGFPE && info->si_code == FPE_NOOP) { 544 int op = pc[0]; 545 546 // Skip REX 547 if ((pc[0] & 0xf0) == 0x40) { 548 op = pc[1]; 549 } else { 550 op = pc[0]; 551 } 552 553 // Check for IDIV 554 if (op == 0xF7) { 555 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime:: IMPLICIT_DIVIDE_BY_ZERO); 556 } else { 557 // TODO: handle more cases if we are using other x86 instructions 558 // that can generate SIGFPE signal. 559 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); 560 fatal("please update this code."); 561 } 562#endif /* __APPLE__ */ 563 564#else 565 if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) { 566 // HACK: si_code does not work on bsd 2.2.12-20!!! 567 int op = pc[0]; 568 if (op == 0xDB) { 569 // FIST 570 // TODO: The encoding of D2I in i486.ad can cause an exception 571 // prior to the fist instruction if there was an invalid operation 572 // pending. We want to dismiss that exception. From the win_32 573 // side it also seems that if it really was the fist causing 574 // the exception that we do the d2i by hand with different 575 // rounding. Seems kind of weird. 576 // NOTE: that we take the exception at the NEXT floating point instruction. 577 assert(pc[0] == 0xDB, "not a FIST opcode"); 578 assert(pc[1] == 0x14, "not a FIST opcode"); 579 assert(pc[2] == 0x24, "not a FIST opcode"); 580 return true; 581 } else if (op == 0xF7) { 582 // IDIV 583 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 584 } else { 585 // TODO: handle more cases if we are using other x86 instructions 586 // that can generate SIGFPE signal on bsd. 587 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); 588 fatal("please update this code."); 589 } 590#endif // AMD64 591 } else if ((sig == SIGSEGV || sig == SIGBUS) && 592 !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 593 // Determination of interpreter/vtable stub/compiled code null exception 594 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 595 } 596 } else if (thread->thread_state() == _thread_in_vm && 597 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */ 598 thread->doing_unsafe_access()) { 599 stub = StubRoutines::handler_for_unsafe_access(); 600 } 601 602 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 603 // and the heap gets shrunk before the field access. 604 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 605 address addr = JNI_FastGetField::find_slowcase_pc(pc); 606 if (addr != (address)-1) { 607 stub = addr; 608 } 609 } 610 611 // Check to see if we caught the safepoint code in the 612 // process of write protecting the memory serialization page. 613 // It write enables the page immediately after protecting it 614 // so we can just return to retry the write. 615 if ((sig == SIGSEGV || sig == SIGBUS) && 616 os::is_memory_serialize_page(thread, (address) info->si_addr)) { 617 // Block current thread until the memory serialize page permission restored. 618 os::block_on_serialize_page_trap(); 619 return true; 620 } 621 } 622 623#ifndef AMD64 624 // Execution protection violation 625 // 626 // This should be kept as the last step in the triage. We don't 627 // have a dedicated trap number for a no-execute fault, so be 628 // conservative and allow other handlers the first shot. 629 // 630 // Note: We don't test that info->si_code == SEGV_ACCERR here. 631 // this si_code is so generic that it is almost meaningless; and 632 // the si_code for this condition may change in the future. 633 // Furthermore, a false-positive should be harmless. 634 if (UnguardOnExecutionViolation > 0 && 635 (sig == SIGSEGV || sig == SIGBUS) && 636 uc->context_trapno == trap_page_fault) { 637 int page_size = os::vm_page_size(); 638 address addr = (address) info->si_addr; 639 address pc = os::Bsd::ucontext_get_pc(uc); 640 // Make sure the pc and the faulting address are sane. 641 // 642 // If an instruction spans a page boundary, and the page containing 643 // the beginning of the instruction is executable but the following 644 // page is not, the pc and the faulting address might be slightly 645 // different - we still want to unguard the 2nd page in this case. 646 // 647 // 15 bytes seems to be a (very) safe value for max instruction size. 648 bool pc_is_near_addr = 649 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 650 bool instr_spans_page_boundary = 651 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 652 (intptr_t) page_size) > 0); 653 654 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 655 static volatile address last_addr = 656 (address) os::non_memory_address_word(); 657 658 // In conservative mode, don't unguard unless the address is in the VM 659 if (addr != last_addr && 660 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 661 662 // Set memory to RWX and retry 663 address page_start = 664 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 665 bool res = os::protect_memory((char*) page_start, page_size, 666 os::MEM_PROT_RWX); 667 668 if (PrintMiscellaneous && Verbose) { 669 char buf[256]; 670 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 671 "at " INTPTR_FORMAT 672 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 673 page_start, (res ? "success" : "failed"), errno); 674 tty->print_raw_cr(buf); 675 } 676 stub = pc; 677 678 // Set last_addr so if we fault again at the same address, we don't end 679 // up in an endless loop. 680 // 681 // There are two potential complications here. Two threads trapping at 682 // the same address at the same time could cause one of the threads to 683 // think it already unguarded, and abort the VM. Likely very rare. 684 // 685 // The other race involves two threads alternately trapping at 686 // different addresses and failing to unguard the page, resulting in 687 // an endless loop. This condition is probably even more unlikely than 688 // the first. 689 // 690 // Although both cases could be avoided by using locks or thread local 691 // last_addr, these solutions are unnecessary complication: this 692 // handler is a best-effort safety net, not a complete solution. It is 693 // disabled by default and should only be used as a workaround in case 694 // we missed any no-execute-unsafe VM code. 695 696 last_addr = addr; 697 } 698 } 699 } 700#endif // !AMD64 701 702 if (stub != NULL) { 703 // save all thread context in case we need to restore it 704 if (thread != NULL) thread->set_saved_exception_pc(pc); 705 706 uc->context_pc = (intptr_t)stub; 707 return true; 708 } 709 710 // signal-chaining 711 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 712 return true; 713 } 714 715 if (!abort_if_unrecognized) { 716 // caller wants another chance, so give it to him 717 return false; 718 } 719 720 if (pc == NULL && uc != NULL) { 721 pc = os::Bsd::ucontext_get_pc(uc); 722 } 723 724 // unmask current signal 725 sigset_t newset; 726 sigemptyset(&newset); 727 sigaddset(&newset, sig); 728 sigprocmask(SIG_UNBLOCK, &newset, NULL); 729 730 VMError err(t, sig, pc, info, ucVoid); 731 err.report_and_die(); 732 733 ShouldNotReachHere(); 734 return false; 735} 736 737// From solaris_i486.s ported to bsd_i486.s 738extern "C" void fixcw(); 739 740void os::Bsd::init_thread_fpu_state(void) { 741#ifndef AMD64 742 // Set fpu to 53 bit precision. This happens too early to use a stub. 743 fixcw(); 744#endif // !AMD64 745} 746 747 748// Check that the bsd kernel version is 2.4 or higher since earlier 749// versions do not support SSE without patches. 750bool os::supports_sse() { 751 return true; 752} 753 754bool os::is_allocatable(size_t bytes) { 755#ifdef AMD64 756 // unused on amd64? 757 return true; 758#else 759 760 if (bytes < 2 * G) { 761 return true; 762 } 763 764 char* addr = reserve_memory(bytes, NULL); 765 766 if (addr != NULL) { 767 release_memory(addr, bytes); 768 } 769 770 return addr != NULL; 771#endif // AMD64 772} 773 774//////////////////////////////////////////////////////////////////////////////// 775// thread stack 776 777#ifdef AMD64 778size_t os::Bsd::min_stack_allowed = 64 * K; 779 780// amd64: pthread on amd64 is always in floating stack mode 781bool os::Bsd::supports_variable_stack_size() { return true; } 782#else 783size_t os::Bsd::min_stack_allowed = (48 DEBUG_ONLY(+4))*K; 784 785#ifdef __GNUC__ 786#define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;}) 787#endif 788 789bool os::Bsd::supports_variable_stack_size() { return true; } 790#endif // AMD64 791 792// return default stack size for thr_type 793size_t os::Bsd::default_stack_size(os::ThreadType thr_type) { 794 // default stack size (compiler thread needs larger stack) 795#ifdef AMD64 796 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M); 797#else 798 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K); 799#endif // AMD64 800 return s; 801} 802 803size_t os::Bsd::default_guard_size(os::ThreadType thr_type) { 804 // Creating guard page is very expensive. Java thread has HotSpot 805 // guard page, only enable glibc guard page for non-Java threads. 806 return (thr_type == java_thread ? 0 : page_size()); 807} 808 809// Java thread: 810// 811// Low memory addresses 812// +------------------------+ 813// | |\ JavaThread created by VM does not have glibc 814// | glibc guard page | - guard, attached Java thread usually has 815// | |/ 1 page glibc guard. 816// P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 817// | |\ 818// | HotSpot Guard Pages | - red and yellow pages 819// | |/ 820// +------------------------+ JavaThread::stack_yellow_zone_base() 821// | |\ 822// | Normal Stack | - 823// | |/ 824// P2 +------------------------+ Thread::stack_base() 825// 826// Non-Java thread: 827// 828// Low memory addresses 829// +------------------------+ 830// | |\ 831// | glibc guard page | - usually 1 page 832// | |/ 833// P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 834// | |\ 835// | Normal Stack | - 836// | |/ 837// P2 +------------------------+ Thread::stack_base() 838// 839// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from 840// pthread_attr_getstack() 841 842static void current_stack_region(address * bottom, size_t * size) { 843#ifdef __APPLE__ 844 pthread_t self = pthread_self(); 845 void *stacktop = pthread_get_stackaddr_np(self); 846 *size = pthread_get_stacksize_np(self); 847 // workaround for OS X 10.9.0 (Mavericks) 848 // pthread_get_stacksize_np returns 128 pages even though the actual size is 2048 pages 849 if (pthread_main_np() == 1) { 850 if ((*size) < (DEFAULT_MAIN_THREAD_STACK_PAGES * (size_t)getpagesize())) { 851 char kern_osrelease[256]; 852 size_t kern_osrelease_size = sizeof(kern_osrelease); 853 int ret = sysctlbyname("kern.osrelease", kern_osrelease, &kern_osrelease_size, NULL, 0); 854 if (ret == 0) { 855 // get the major number, atoi will ignore the minor amd micro portions of the version string 856 if (atoi(kern_osrelease) >= OS_X_10_9_0_KERNEL_MAJOR_VERSION) { 857 *size = (DEFAULT_MAIN_THREAD_STACK_PAGES*getpagesize()); 858 } 859 } 860 } 861 } 862 *bottom = (address) stacktop - *size; 863#elif defined(__OpenBSD__) 864 stack_t ss; 865 int rslt = pthread_stackseg_np(pthread_self(), &ss); 866 867 if (rslt != 0) 868 fatal(err_msg("pthread_stackseg_np failed with err = %d", rslt)); 869 870 *bottom = (address)((char *)ss.ss_sp - ss.ss_size); 871 *size = ss.ss_size; 872#else 873 pthread_attr_t attr; 874 875 int rslt = pthread_attr_init(&attr); 876 877 // JVM needs to know exact stack location, abort if it fails 878 if (rslt != 0) 879 fatal(err_msg("pthread_attr_init failed with err = %d", rslt)); 880 881 rslt = pthread_attr_get_np(pthread_self(), &attr); 882 883 if (rslt != 0) 884 fatal(err_msg("pthread_attr_get_np failed with err = %d", rslt)); 885 886 if (pthread_attr_getstackaddr(&attr, (void **)bottom) != 0 || 887 pthread_attr_getstacksize(&attr, size) != 0) { 888 fatal("Can not locate current stack attributes!"); 889 } 890 891 pthread_attr_destroy(&attr); 892#endif 893 assert(os::current_stack_pointer() >= *bottom && 894 os::current_stack_pointer() < *bottom + *size, "just checking"); 895} 896 897address os::current_stack_base() { 898 address bottom; 899 size_t size; 900 current_stack_region(&bottom, &size); 901 return (bottom + size); 902} 903 904size_t os::current_stack_size() { 905 // stack size includes normal stack and HotSpot guard pages 906 address bottom; 907 size_t size; 908 current_stack_region(&bottom, &size); 909 return size; 910} 911 912///////////////////////////////////////////////////////////////////////////// 913// helper functions for fatal error handler 914 915void os::print_context(outputStream *st, void *context) { 916 if (context == NULL) return; 917 918 ucontext_t *uc = (ucontext_t*)context; 919 st->print_cr("Registers:"); 920#ifdef AMD64 921 st->print( "RAX=" INTPTR_FORMAT, uc->context_rax); 922 st->print(", RBX=" INTPTR_FORMAT, uc->context_rbx); 923 st->print(", RCX=" INTPTR_FORMAT, uc->context_rcx); 924 st->print(", RDX=" INTPTR_FORMAT, uc->context_rdx); 925 st->cr(); 926 st->print( "RSP=" INTPTR_FORMAT, uc->context_rsp); 927 st->print(", RBP=" INTPTR_FORMAT, uc->context_rbp); 928 st->print(", RSI=" INTPTR_FORMAT, uc->context_rsi); 929 st->print(", RDI=" INTPTR_FORMAT, uc->context_rdi); 930 st->cr(); 931 st->print( "R8 =" INTPTR_FORMAT, uc->context_r8); 932 st->print(", R9 =" INTPTR_FORMAT, uc->context_r9); 933 st->print(", R10=" INTPTR_FORMAT, uc->context_r10); 934 st->print(", R11=" INTPTR_FORMAT, uc->context_r11); 935 st->cr(); 936 st->print( "R12=" INTPTR_FORMAT, uc->context_r12); 937 st->print(", R13=" INTPTR_FORMAT, uc->context_r13); 938 st->print(", R14=" INTPTR_FORMAT, uc->context_r14); 939 st->print(", R15=" INTPTR_FORMAT, uc->context_r15); 940 st->cr(); 941 st->print( "RIP=" INTPTR_FORMAT, uc->context_rip); 942 st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_flags); 943 st->print(", ERR=" INTPTR_FORMAT, uc->context_err); 944 st->cr(); 945 st->print(" TRAPNO=" INTPTR_FORMAT, uc->context_trapno); 946#else 947 st->print( "EAX=" INTPTR_FORMAT, uc->context_eax); 948 st->print(", EBX=" INTPTR_FORMAT, uc->context_ebx); 949 st->print(", ECX=" INTPTR_FORMAT, uc->context_ecx); 950 st->print(", EDX=" INTPTR_FORMAT, uc->context_edx); 951 st->cr(); 952 st->print( "ESP=" INTPTR_FORMAT, uc->context_esp); 953 st->print(", EBP=" INTPTR_FORMAT, uc->context_ebp); 954 st->print(", ESI=" INTPTR_FORMAT, uc->context_esi); 955 st->print(", EDI=" INTPTR_FORMAT, uc->context_edi); 956 st->cr(); 957 st->print( "EIP=" INTPTR_FORMAT, uc->context_eip); 958 st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_eflags); 959#endif // AMD64 960 st->cr(); 961 st->cr(); 962 963 intptr_t *sp = (intptr_t *)os::Bsd::ucontext_get_sp(uc); 964 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 965 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 966 st->cr(); 967 968 // Note: it may be unsafe to inspect memory near pc. For example, pc may 969 // point to garbage if entry point in an nmethod is corrupted. Leave 970 // this at the end, and hope for the best. 971 address pc = os::Bsd::ucontext_get_pc(uc); 972 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 973 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 974} 975 976void os::print_register_info(outputStream *st, void *context) { 977 if (context == NULL) return; 978 979 ucontext_t *uc = (ucontext_t*)context; 980 981 st->print_cr("Register to memory mapping:"); 982 st->cr(); 983 984 // this is horrendously verbose but the layout of the registers in the 985 // context does not match how we defined our abstract Register set, so 986 // we can't just iterate through the gregs area 987 988 // this is only for the "general purpose" registers 989 990#ifdef AMD64 991 st->print("RAX="); print_location(st, uc->context_rax); 992 st->print("RBX="); print_location(st, uc->context_rbx); 993 st->print("RCX="); print_location(st, uc->context_rcx); 994 st->print("RDX="); print_location(st, uc->context_rdx); 995 st->print("RSP="); print_location(st, uc->context_rsp); 996 st->print("RBP="); print_location(st, uc->context_rbp); 997 st->print("RSI="); print_location(st, uc->context_rsi); 998 st->print("RDI="); print_location(st, uc->context_rdi); 999 st->print("R8 ="); print_location(st, uc->context_r8); 1000 st->print("R9 ="); print_location(st, uc->context_r9); 1001 st->print("R10="); print_location(st, uc->context_r10); 1002 st->print("R11="); print_location(st, uc->context_r11); 1003 st->print("R12="); print_location(st, uc->context_r12); 1004 st->print("R13="); print_location(st, uc->context_r13); 1005 st->print("R14="); print_location(st, uc->context_r14); 1006 st->print("R15="); print_location(st, uc->context_r15); 1007#else 1008 st->print("EAX="); print_location(st, uc->context_eax); 1009 st->print("EBX="); print_location(st, uc->context_ebx); 1010 st->print("ECX="); print_location(st, uc->context_ecx); 1011 st->print("EDX="); print_location(st, uc->context_edx); 1012 st->print("ESP="); print_location(st, uc->context_esp); 1013 st->print("EBP="); print_location(st, uc->context_ebp); 1014 st->print("ESI="); print_location(st, uc->context_esi); 1015 st->print("EDI="); print_location(st, uc->context_edi); 1016#endif // AMD64 1017 1018 st->cr(); 1019} 1020 1021void os::setup_fpu() { 1022#ifndef AMD64 1023 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 1024 __asm__ volatile ( "fldcw (%0)" : 1025 : "r" (fpu_cntrl) : "memory"); 1026#endif // !AMD64 1027} 1028 1029#ifndef PRODUCT 1030void os::verify_stack_alignment() { 1031} 1032#endif 1033