os_solaris_x86.cpp revision 0:a61af66fc99e
1/* 2 * Copyright 1999-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25// do not include precompiled header file 26# include "incls/_os_solaris_x86.cpp.incl" 27 28// put OS-includes here 29# include <sys/types.h> 30# include <sys/mman.h> 31# include <pthread.h> 32# include <signal.h> 33# include <setjmp.h> 34# include <errno.h> 35# include <dlfcn.h> 36# include <stdio.h> 37# include <unistd.h> 38# include <sys/resource.h> 39# include <thread.h> 40# include <sys/stat.h> 41# include <sys/time.h> 42# include <sys/filio.h> 43# include <sys/utsname.h> 44# include <sys/systeminfo.h> 45# include <sys/socket.h> 46# include <sys/trap.h> 47# include <sys/lwp.h> 48# include <pwd.h> 49# include <poll.h> 50# include <sys/lwp.h> 51# include <procfs.h> // see comment in <sys/procfs.h> 52 53#ifndef AMD64 54// QQQ seems useless at this point 55# define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later 56#endif // AMD64 57# include <sys/procfs.h> // see comment in <sys/procfs.h> 58 59 60#define MAX_PATH (2 * K) 61 62// Minimum stack size for the VM. It's easier to document a constant value 63// but it's different for x86 and sparc because the page sizes are different. 64#ifdef AMD64 65size_t os::Solaris::min_stack_allowed = 224*K; 66#define REG_SP REG_RSP 67#define REG_PC REG_RIP 68#define REG_FP REG_RBP 69#else 70size_t os::Solaris::min_stack_allowed = 64*K; 71#define REG_SP UESP 72#define REG_PC EIP 73#define REG_FP EBP 74// 4900493 counter to prevent runaway LDTR refresh attempt 75 76static volatile int ldtr_refresh = 0; 77// the libthread instruction that faults because of the stale LDTR 78 79static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs 80 }; 81#endif // AMD64 82 83char* os::non_memory_address_word() { 84 // Must never look like an address returned by reserve_memory, 85 // even in its subfields (as defined by the CPU immediate fields, 86 // if the CPU splits constants across multiple instructions). 87 return (char*) -1; 88} 89 90// 91// Validate a ucontext retrieved from walking a uc_link of a ucontext. 92// There are issues with libthread giving out uc_links for different threads 93// on the same uc_link chain and bad or circular links. 94// 95bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) { 96 if (valid >= suspect || 97 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags || 98 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp || 99 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) { 100 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");) 101 return false; 102 } 103 104 if (thread->is_Java_thread()) { 105 if (!valid_stack_address(thread, (address)suspect)) { 106 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");) 107 return false; 108 } 109 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) { 110 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");) 111 return false; 112 } 113 } 114 return true; 115} 116 117// We will only follow one level of uc_link since there are libthread 118// issues with ucontext linking and it is better to be safe and just 119// let caller retry later. 120ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread, 121 ucontext_t *uc) { 122 123 ucontext_t *retuc = NULL; 124 125 if (uc != NULL) { 126 if (uc->uc_link == NULL) { 127 // cannot validate without uc_link so accept current ucontext 128 retuc = uc; 129 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 130 // first ucontext is valid so try the next one 131 uc = uc->uc_link; 132 if (uc->uc_link == NULL) { 133 // cannot validate without uc_link so accept current ucontext 134 retuc = uc; 135 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 136 // the ucontext one level down is also valid so return it 137 retuc = uc; 138 } 139 } 140 } 141 return retuc; 142} 143 144// Assumes ucontext is valid 145ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) { 146 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]); 147} 148 149// Assumes ucontext is valid 150intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) { 151 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP]; 152} 153 154// Assumes ucontext is valid 155intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) { 156 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP]; 157} 158 159// For Forte Analyzer AsyncGetCallTrace profiling support - thread 160// is currently interrupted by SIGPROF. 161// 162// The difference between this and os::fetch_frame_from_context() is that 163// here we try to skip nested signal frames. 164ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread, 165 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 166 167 assert(thread != NULL, "just checking"); 168 assert(ret_sp != NULL, "just checking"); 169 assert(ret_fp != NULL, "just checking"); 170 171 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc); 172 return os::fetch_frame_from_context(luc, ret_sp, ret_fp); 173} 174 175ExtendedPC os::fetch_frame_from_context(void* ucVoid, 176 intptr_t** ret_sp, intptr_t** ret_fp) { 177 178 ExtendedPC epc; 179 ucontext_t *uc = (ucontext_t*)ucVoid; 180 181 if (uc != NULL) { 182 epc = os::Solaris::ucontext_get_ExtendedPC(uc); 183 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc); 184 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc); 185 } else { 186 // construct empty ExtendedPC for return value checking 187 epc = ExtendedPC(NULL); 188 if (ret_sp) *ret_sp = (intptr_t *)NULL; 189 if (ret_fp) *ret_fp = (intptr_t *)NULL; 190 } 191 192 return epc; 193} 194 195frame os::fetch_frame_from_context(void* ucVoid) { 196 intptr_t* sp; 197 intptr_t* fp; 198 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 199 return frame(sp, fp, epc.pc()); 200} 201 202frame os::get_sender_for_C_frame(frame* fr) { 203 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 204} 205 206extern "C" intptr_t *_get_previous_fp(); // in .il file. 207 208frame os::current_frame() { 209 intptr_t* fp = _get_previous_fp(); 210 frame myframe((intptr_t*)os::current_stack_pointer(), 211 (intptr_t*)fp, 212 CAST_FROM_FN_PTR(address, os::current_frame)); 213 if (os::is_first_C_frame(&myframe)) { 214 // stack is not walkable 215 return frame(NULL, NULL, NULL); 216 } else { 217 return os::get_sender_for_C_frame(&myframe); 218 } 219} 220 221// This is a simple callback that just fetches a PC for an interrupted thread. 222// The thread need not be suspended and the fetched PC is just a hint. 223// This one is currently used for profiling the VMThread ONLY! 224 225// Must be synchronous 226void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) { 227 Thread* thread = args->thread(); 228 ucontext_t* uc = args->ucontext(); 229 intptr_t* sp; 230 231 assert(ProfileVM && thread->is_VM_thread(), "just checking"); 232 233 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]); 234 _addr = new_addr; 235} 236 237static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) { 238 char lwpstatusfile[PROCFILE_LENGTH]; 239 int lwpfd, err; 240 241 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs)) 242 return (err); 243 if (*flags == TRS_LWPID) { 244 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(), 245 *lwp); 246 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) { 247 perror("thr_mutator_status: open lwpstatus"); 248 return (EINVAL); 249 } 250 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) != 251 sizeof (lwpstatus_t)) { 252 perror("thr_mutator_status: read lwpstatus"); 253 (void) close(lwpfd); 254 return (EINVAL); 255 } 256 (void) close(lwpfd); 257 } 258 return (0); 259} 260 261#ifndef AMD64 262 263// Detecting SSE support by OS 264// From solaris_i486.s 265extern "C" bool sse_check(); 266extern "C" bool sse_unavailable(); 267 268enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 269static int sse_status = SSE_UNKNOWN; 270 271 272static void check_for_sse_support() { 273 if (!VM_Version::supports_sse()) { 274 sse_status = SSE_NOT_SUPPORTED; 275 return; 276 } 277 // looking for _sse_hw in libc.so, if it does not exist or 278 // the value (int) is 0, OS has no support for SSE 279 int *sse_hwp; 280 void *h; 281 282 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 283 //open failed, presume no support for SSE 284 sse_status = SSE_NOT_SUPPORTED; 285 return; 286 } 287 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 288 sse_status = SSE_NOT_SUPPORTED; 289 } else if (*sse_hwp == 0) { 290 sse_status = SSE_NOT_SUPPORTED; 291 } 292 dlclose(h); 293 294 if (sse_status == SSE_UNKNOWN) { 295 bool (*try_sse)() = (bool (*)())sse_check; 296 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 297 } 298 299} 300 301bool os::supports_sse() { 302 if (sse_status == SSE_UNKNOWN) 303 check_for_sse_support(); 304 return sse_status == SSE_SUPPORTED; 305} 306 307#endif // AMD64 308 309bool os::is_allocatable(size_t bytes) { 310#ifdef AMD64 311 return true; 312#else 313 314 if (bytes < 2 * G) { 315 return true; 316 } 317 318 char* addr = reserve_memory(bytes, NULL); 319 320 if (addr != NULL) { 321 release_memory(addr, bytes); 322 } 323 324 return addr != NULL; 325#endif // AMD64 326 327} 328 329extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized); 330 331extern "C" void Fetch32PFI () ; 332extern "C" void Fetch32Resume () ; 333#ifdef AMD64 334extern "C" void FetchNPFI () ; 335extern "C" void FetchNResume () ; 336#endif // AMD64 337 338int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) { 339 ucontext_t* uc = (ucontext_t*) ucVoid; 340 341#ifndef AMD64 342 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 343 // the SSE instruction faulted. supports_sse() need return false. 344 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 345 return true; 346 } 347#endif // !AMD64 348 349 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady 350 351 SignalHandlerMark shm(t); 352 353 if(sig == SIGPIPE || sig == SIGXFSZ) { 354 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 355 return true; 356 } else { 357 if (PrintMiscellaneous && (WizardMode || Verbose)) { 358 char buf[64]; 359 warning("Ignoring %s - see 4229104 or 6499219", 360 os::exception_name(sig, buf, sizeof(buf))); 361 362 } 363 return true; 364 } 365 } 366 367 JavaThread* thread = NULL; 368 VMThread* vmthread = NULL; 369 370 if (os::Solaris::signal_handlers_are_installed) { 371 if (t != NULL ){ 372 if(t->is_Java_thread()) { 373 thread = (JavaThread*)t; 374 } 375 else if(t->is_VM_thread()){ 376 vmthread = (VMThread *)t; 377 } 378 } 379 } 380 381 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs"); 382 383 if (sig == os::Solaris::SIGasync()) { 384 if(thread){ 385 OSThread::InterruptArguments args(thread, uc); 386 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 387 return true; 388 } 389 else if(vmthread){ 390 OSThread::InterruptArguments args(vmthread, uc); 391 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 392 return true; 393 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 394 return true; 395 } else { 396 // If os::Solaris::SIGasync not chained, and this is a non-vm and 397 // non-java thread 398 return true; 399 } 400 } 401 402 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 403 // can't decode this kind of signal 404 info = NULL; 405 } else { 406 assert(sig == info->si_signo, "bad siginfo"); 407 } 408 409 // decide if this trap can be handled by a stub 410 address stub = NULL; 411 412 address pc = NULL; 413 414 //%note os_trap_1 415 if (info != NULL && uc != NULL && thread != NULL) { 416 // factor me: getPCfromContext 417 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 418 419 // SafeFetch32() support 420 if (pc == (address) Fetch32PFI) { 421 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ; 422 return true ; 423 } 424#ifdef AMD64 425 if (pc == (address) FetchNPFI) { 426 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ; 427 return true ; 428 } 429#endif // AMD64 430 431 // Handle ALL stack overflow variations here 432 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 433 address addr = (address) info->si_addr; 434 if (thread->in_stack_yellow_zone(addr)) { 435 thread->disable_stack_yellow_zone(); 436 if (thread->thread_state() == _thread_in_Java) { 437 // Throw a stack overflow exception. Guard pages will be reenabled 438 // while unwinding the stack. 439 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 440 } else { 441 // Thread was in the vm or native code. Return and try to finish. 442 return true; 443 } 444 } else if (thread->in_stack_red_zone(addr)) { 445 // Fatal red zone violation. Disable the guard pages and fall through 446 // to handle_unexpected_exception way down below. 447 thread->disable_stack_red_zone(); 448 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 449 } 450 } 451 452 if (thread->thread_state() == _thread_in_vm) { 453 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 454 stub = StubRoutines::handler_for_unsafe_access(); 455 } 456 } 457 458 if (thread->thread_state() == _thread_in_Java) { 459 // Support Safepoint Polling 460 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 461 stub = SharedRuntime::get_poll_stub(pc); 462 } 463 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 464 // BugId 4454115: A read from a MappedByteBuffer can fault 465 // here if the underlying file has been truncated. 466 // Do not crash the VM in such a case. 467 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 468 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL; 469 if (nm != NULL && nm->has_unsafe_access()) { 470 stub = StubRoutines::handler_for_unsafe_access(); 471 } 472 } 473 else 474 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 475 // integer divide by zero 476 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 477 } 478#ifndef AMD64 479 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 480 // floating-point divide by zero 481 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 482 } 483 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 484 // The encoding of D2I in i486.ad can cause an exception prior 485 // to the fist instruction if there was an invalid operation 486 // pending. We want to dismiss that exception. From the win_32 487 // side it also seems that if it really was the fist causing 488 // the exception that we do the d2i by hand with different 489 // rounding. Seems kind of weird. QQQ TODO 490 // Note that we take the exception at the NEXT floating point instruction. 491 if (pc[0] == 0xDB) { 492 assert(pc[0] == 0xDB, "not a FIST opcode"); 493 assert(pc[1] == 0x14, "not a FIST opcode"); 494 assert(pc[2] == 0x24, "not a FIST opcode"); 495 return true; 496 } else { 497 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 498 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 499 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 500 } 501 } 502 else if (sig == SIGFPE ) { 503 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 504 } 505#endif // !AMD64 506 507 // QQQ It doesn't seem that we need to do this on x86 because we should be able 508 // to return properly from the handler without this extra stuff on the back side. 509 510 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 511 // Determination of interpreter/vtable stub/compiled code null exception 512 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 513 } 514 } 515 516 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 517 // and the heap gets shrunk before the field access. 518 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 519 address addr = JNI_FastGetField::find_slowcase_pc(pc); 520 if (addr != (address)-1) { 521 stub = addr; 522 } 523 } 524 525 // Check to see if we caught the safepoint code in the 526 // process of write protecting the memory serialization page. 527 // It write enables the page immediately after protecting it 528 // so we can just return to retry the write. 529 if ((sig == SIGSEGV) && 530 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 531 // Block current thread until the memory serialize page permission restored. 532 os::block_on_serialize_page_trap(); 533 return true; 534 } 535 } 536 537 // Execution protection violation 538 // 539 // Preventative code for future versions of Solaris which may 540 // enable execution protection when running the 32-bit VM on AMD64. 541 // 542 // This should be kept as the last step in the triage. We don't 543 // have a dedicated trap number for a no-execute fault, so be 544 // conservative and allow other handlers the first shot. 545 // 546 // Note: We don't test that info->si_code == SEGV_ACCERR here. 547 // this si_code is so generic that it is almost meaningless; and 548 // the si_code for this condition may change in the future. 549 // Furthermore, a false-positive should be harmless. 550 if (UnguardOnExecutionViolation > 0 && 551 (sig == SIGSEGV || sig == SIGBUS) && 552 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 553 int page_size = os::vm_page_size(); 554 address addr = (address) info->si_addr; 555 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 556 // Make sure the pc and the faulting address are sane. 557 // 558 // If an instruction spans a page boundary, and the page containing 559 // the beginning of the instruction is executable but the following 560 // page is not, the pc and the faulting address might be slightly 561 // different - we still want to unguard the 2nd page in this case. 562 // 563 // 15 bytes seems to be a (very) safe value for max instruction size. 564 bool pc_is_near_addr = 565 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 566 bool instr_spans_page_boundary = 567 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 568 (intptr_t) page_size) > 0); 569 570 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 571 static volatile address last_addr = 572 (address) os::non_memory_address_word(); 573 574 // In conservative mode, don't unguard unless the address is in the VM 575 if (addr != last_addr && 576 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 577 578 // Unguard and retry 579 address page_start = 580 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 581 bool res = os::unguard_memory((char*) page_start, page_size); 582 583 if (PrintMiscellaneous && Verbose) { 584 char buf[256]; 585 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 586 "at " INTPTR_FORMAT 587 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 588 page_start, (res ? "success" : "failed"), errno); 589 tty->print_raw_cr(buf); 590 } 591 stub = pc; 592 593 // Set last_addr so if we fault again at the same address, we don't end 594 // up in an endless loop. 595 // 596 // There are two potential complications here. Two threads trapping at 597 // the same address at the same time could cause one of the threads to 598 // think it already unguarded, and abort the VM. Likely very rare. 599 // 600 // The other race involves two threads alternately trapping at 601 // different addresses and failing to unguard the page, resulting in 602 // an endless loop. This condition is probably even more unlikely than 603 // the first. 604 // 605 // Although both cases could be avoided by using locks or thread local 606 // last_addr, these solutions are unnecessary complication: this 607 // handler is a best-effort safety net, not a complete solution. It is 608 // disabled by default and should only be used as a workaround in case 609 // we missed any no-execute-unsafe VM code. 610 611 last_addr = addr; 612 } 613 } 614 } 615 616 if (stub != NULL) { 617 // save all thread context in case we need to restore it 618 619 if (thread != NULL) thread->set_saved_exception_pc(pc); 620 // 12/02/99: On Sparc it appears that the full context is also saved 621 // but as yet, no one looks at or restores that saved context 622 // factor me: setPC 623 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub; 624 return true; 625 } 626 627 // signal-chaining 628 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 629 return true; 630 } 631 632#ifndef AMD64 633 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 634 // Handle an undefined selector caused by an attempt to assign 635 // fs in libthread getipriptr(). With the current libthread design every 512 636 // thread creations the LDT for a private thread data structure is extended 637 // and thre is a hazard that and another thread attempting a thread creation 638 // will use a stale LDTR that doesn't reflect the structure's growth, 639 // causing a GP fault. 640 // Enforce the probable limit of passes through here to guard against an 641 // infinite loop if some other move to fs caused the GP fault. Note that 642 // this loop counter is ultimately a heuristic as it is possible for 643 // more than one thread to generate this fault at a time in an MP system. 644 // In the case of the loop count being exceeded or if the poll fails 645 // just fall through to a fatal error. 646 // If there is some other source of T_GPFLT traps and the text at EIP is 647 // unreadable this code will loop infinitely until the stack is exausted. 648 // The key to diagnosis in this case is to look for the bottom signal handler 649 // frame. 650 651 if(! IgnoreLibthreadGPFault) { 652 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 653 const unsigned char *p = 654 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 655 656 // Expected instruction? 657 658 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 659 660 Atomic::inc(&ldtr_refresh); 661 662 // Infinite loop? 663 664 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 665 666 // No, force scheduling to get a fresh view of the LDTR 667 668 if(poll(NULL, 0, 10) == 0) { 669 670 // Retry the move 671 672 return false; 673 } 674 } 675 } 676 } 677 } 678#endif // !AMD64 679 680 if (!abort_if_unrecognized) { 681 // caller wants another chance, so give it to him 682 return false; 683 } 684 685 if (!os::Solaris::libjsig_is_loaded) { 686 struct sigaction oldAct; 687 sigaction(sig, (struct sigaction *)0, &oldAct); 688 if (oldAct.sa_sigaction != signalHandler) { 689 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 690 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 691 warning("Unexpected Signal %d occured under user-defined signal handler %#lx", sig, (long)sighand); 692 } 693 } 694 695 if (pc == NULL && uc != NULL) { 696 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 697 } 698 699 // unmask current signal 700 sigset_t newset; 701 sigemptyset(&newset); 702 sigaddset(&newset, sig); 703 sigprocmask(SIG_UNBLOCK, &newset, NULL); 704 705 VMError err(t, sig, pc, info, ucVoid); 706 err.report_and_die(); 707 708 ShouldNotReachHere(); 709} 710 711void os::print_context(outputStream *st, void *context) { 712 if (context == NULL) return; 713 714 ucontext_t *uc = (ucontext_t*)context; 715 st->print_cr("Registers:"); 716#ifdef AMD64 717 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 718 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 719 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 720 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 721 st->cr(); 722 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 723 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 724 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 725 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 726 st->cr(); 727 st->print(", R8=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 728 st->print(", R9=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 729 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 730 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 731 st->print(", R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 732 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 733 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 734 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 735 st->cr(); 736 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 737 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 738#else 739 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 740 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 741 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 742 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 743 st->cr(); 744 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 745 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 746 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 747 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 748 st->cr(); 749 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 750 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 751#endif // AMD64 752 st->cr(); 753 st->cr(); 754 755 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 756 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 757 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 758 st->cr(); 759 760 // Note: it may be unsafe to inspect memory near pc. For example, pc may 761 // point to garbage if entry point in an nmethod is corrupted. Leave 762 // this at the end, and hope for the best. 763 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 764 address pc = epc.pc(); 765 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 766 print_hex_dump(st, pc - 16, pc + 16, sizeof(char)); 767} 768 769#ifdef AMD64 770void os::Solaris::init_thread_fpu_state(void) { 771 // Nothing to do 772} 773#else 774// From solaris_i486.s 775extern "C" void fixcw(); 776 777void os::Solaris::init_thread_fpu_state(void) { 778 // Set fpu to 53 bit precision. This happens too early to use a stub. 779 fixcw(); 780} 781 782// These routines are the initial value of atomic_xchg_entry(), 783// atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 784// until initialization is complete. 785// TODO - replace with .il implementation when compiler supports it. 786 787typedef jint xchg_func_t (jint, volatile jint*); 788typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 789typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 790typedef jint add_func_t (jint, volatile jint*); 791typedef void fence_func_t (); 792 793jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 794 // try to use the stub: 795 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 796 797 if (func != NULL) { 798 os::atomic_xchg_func = func; 799 return (*func)(exchange_value, dest); 800 } 801 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 802 803 jint old_value = *dest; 804 *dest = exchange_value; 805 return old_value; 806} 807 808jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 809 // try to use the stub: 810 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 811 812 if (func != NULL) { 813 os::atomic_cmpxchg_func = func; 814 return (*func)(exchange_value, dest, compare_value); 815 } 816 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 817 818 jint old_value = *dest; 819 if (old_value == compare_value) 820 *dest = exchange_value; 821 return old_value; 822} 823 824jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 825 // try to use the stub: 826 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 827 828 if (func != NULL) { 829 os::atomic_cmpxchg_long_func = func; 830 return (*func)(exchange_value, dest, compare_value); 831 } 832 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 833 834 jlong old_value = *dest; 835 if (old_value == compare_value) 836 *dest = exchange_value; 837 return old_value; 838} 839 840jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 841 // try to use the stub: 842 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 843 844 if (func != NULL) { 845 os::atomic_add_func = func; 846 return (*func)(add_value, dest); 847 } 848 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 849 850 return (*dest) += add_value; 851} 852 853void os::fence_bootstrap() { 854 // try to use the stub: 855 fence_func_t* func = CAST_TO_FN_PTR(fence_func_t*, StubRoutines::fence_entry()); 856 857 if (func != NULL) { 858 os::fence_func = func; 859 (*func)(); 860 return; 861 } 862 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 863 864 // don't have to do anything for a single thread 865} 866 867xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 868cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 869cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 870add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 871fence_func_t* os::fence_func = os::fence_bootstrap; 872 873extern "C" _solaris_raw_setup_fpu(address ptr); 874void os::setup_fpu() { 875 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 876 _solaris_raw_setup_fpu(fpu_cntrl); 877} 878#endif // AMD64 879