1 /* 2 * Copyright 1999-2009 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 65 size_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 70 size_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 76 static volatile int ldtr_refresh = 0; 77 // the libthread instruction that faults because of the stale LDTR 78 79 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs 80 }; 81 #endif // AMD64 82 83 char* 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 // 95 bool 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. 120 ucontext_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 145 ExtendedPC 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 150 intptr_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 155 intptr_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. 164 ExtendedPC 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 } 174 175 ExtendedPC 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 } 194 195 frame 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 } 201 202 frame os::get_sender_for_C_frame(frame* fr) { 203 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 204 } 205 206 extern "C" intptr_t *_get_current_fp(); // in .il file 207 208 frame os::current_frame() { 209 intptr_t* fp = _get_current_fp(); // it's inlined so want current 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 frame ret; // This will be a null useless frame 216 return ret; 217 } else { 218 return os::get_sender_for_C_frame(&myframe); 219 } 220 } 221 222 // This is a simple callback that just fetches a PC for an interrupted thread. 223 // The thread need not be suspended and the fetched PC is just a hint. 224 // This one is currently used for profiling the VMThread ONLY! 225 226 // Must be synchronous 227 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) { 228 Thread* thread = args->thread(); 229 ucontext_t* uc = args->ucontext(); 230 intptr_t* sp; 231 232 assert(ProfileVM && thread->is_VM_thread(), "just checking"); 233 234 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]); 235 _addr = new_addr; 236 } 237 238 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) { 239 char lwpstatusfile[PROCFILE_LENGTH]; 240 int lwpfd, err; 241 242 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs)) 243 return (err); 244 if (*flags == TRS_LWPID) { 245 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(), 246 *lwp); 247 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) { 248 perror("thr_mutator_status: open lwpstatus"); 249 return (EINVAL); 250 } 251 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) != 252 sizeof (lwpstatus_t)) { 253 perror("thr_mutator_status: read lwpstatus"); 254 (void) close(lwpfd); 255 return (EINVAL); 256 } 257 (void) close(lwpfd); 258 } 259 return (0); 260 } 261 262 #ifndef AMD64 263 264 // Detecting SSE support by OS 265 // From solaris_i486.s 266 extern "C" bool sse_check(); 267 extern "C" bool sse_unavailable(); 268 269 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 270 static int sse_status = SSE_UNKNOWN; 271 272 273 static void check_for_sse_support() { 274 if (!VM_Version::supports_sse()) { 275 sse_status = SSE_NOT_SUPPORTED; 276 return; 277 } 278 // looking for _sse_hw in libc.so, if it does not exist or 279 // the value (int) is 0, OS has no support for SSE 280 int *sse_hwp; 281 void *h; 282 283 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 284 //open failed, presume no support for SSE 285 sse_status = SSE_NOT_SUPPORTED; 286 return; 287 } 288 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 289 sse_status = SSE_NOT_SUPPORTED; 290 } else if (*sse_hwp == 0) { 291 sse_status = SSE_NOT_SUPPORTED; 292 } 293 dlclose(h); 294 295 if (sse_status == SSE_UNKNOWN) { 296 bool (*try_sse)() = (bool (*)())sse_check; 297 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 298 } 299 300 } 301 302 #endif // AMD64 303 304 bool os::supports_sse() { 305 #ifdef AMD64 306 return true; 307 #else 308 if (sse_status == SSE_UNKNOWN) 309 check_for_sse_support(); 310 return sse_status == SSE_SUPPORTED; 311 #endif // AMD64 312 } 313 314 bool os::is_allocatable(size_t bytes) { 315 #ifdef AMD64 316 return true; 317 #else 318 319 if (bytes < 2 * G) { 320 return true; 321 } 322 323 char* addr = reserve_memory(bytes, NULL); 324 325 if (addr != NULL) { 326 release_memory(addr, bytes); 327 } 328 329 return addr != NULL; 330 #endif // AMD64 331 332 } 333 334 extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized); 335 336 extern "C" void Fetch32PFI () ; 337 extern "C" void Fetch32Resume () ; 338 #ifdef AMD64 339 extern "C" void FetchNPFI () ; 340 extern "C" void FetchNResume () ; 341 #endif // AMD64 342 343 int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) { 344 ucontext_t* uc = (ucontext_t*) ucVoid; 345 346 #ifndef AMD64 347 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 348 // the SSE instruction faulted. supports_sse() need return false. 349 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 350 return true; 351 } 352 #endif // !AMD64 353 354 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady 355 356 SignalHandlerMark shm(t); 357 358 if(sig == SIGPIPE || sig == SIGXFSZ) { 359 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 360 return true; 361 } else { 362 if (PrintMiscellaneous && (WizardMode || Verbose)) { 363 char buf[64]; 364 warning("Ignoring %s - see 4229104 or 6499219", 365 os::exception_name(sig, buf, sizeof(buf))); 366 367 } 368 return true; 369 } 370 } 371 372 JavaThread* thread = NULL; 373 VMThread* vmthread = NULL; 374 375 if (os::Solaris::signal_handlers_are_installed) { 376 if (t != NULL ){ 377 if(t->is_Java_thread()) { 378 thread = (JavaThread*)t; 379 } 380 else if(t->is_VM_thread()){ 381 vmthread = (VMThread *)t; 382 } 383 } 384 } 385 386 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs"); 387 388 if (sig == os::Solaris::SIGasync()) { 389 if(thread){ 390 OSThread::InterruptArguments args(thread, uc); 391 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 392 return true; 393 } 394 else if(vmthread){ 395 OSThread::InterruptArguments args(vmthread, uc); 396 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 397 return true; 398 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 399 return true; 400 } else { 401 // If os::Solaris::SIGasync not chained, and this is a non-vm and 402 // non-java thread 403 return true; 404 } 405 } 406 407 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 408 // can't decode this kind of signal 409 info = NULL; 410 } else { 411 assert(sig == info->si_signo, "bad siginfo"); 412 } 413 414 // decide if this trap can be handled by a stub 415 address stub = NULL; 416 417 address pc = NULL; 418 419 //%note os_trap_1 420 if (info != NULL && uc != NULL && thread != NULL) { 421 // factor me: getPCfromContext 422 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 423 424 // SafeFetch32() support 425 if (pc == (address) Fetch32PFI) { 426 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ; 427 return true ; 428 } 429 #ifdef AMD64 430 if (pc == (address) FetchNPFI) { 431 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ; 432 return true ; 433 } 434 #endif // AMD64 435 436 // Handle ALL stack overflow variations here 437 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 438 address addr = (address) info->si_addr; 439 if (thread->in_stack_yellow_zone(addr)) { 440 thread->disable_stack_yellow_zone(); 441 if (thread->thread_state() == _thread_in_Java) { 442 // Throw a stack overflow exception. Guard pages will be reenabled 443 // while unwinding the stack. 444 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 445 } else { 446 // Thread was in the vm or native code. Return and try to finish. 447 return true; 448 } 449 } else if (thread->in_stack_red_zone(addr)) { 450 // Fatal red zone violation. Disable the guard pages and fall through 451 // to handle_unexpected_exception way down below. 452 thread->disable_stack_red_zone(); 453 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 454 } 455 } 456 457 if (thread->thread_state() == _thread_in_vm) { 458 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 459 stub = StubRoutines::handler_for_unsafe_access(); 460 } 461 } 462 463 if (thread->thread_state() == _thread_in_Java) { 464 // Support Safepoint Polling 465 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 466 stub = SharedRuntime::get_poll_stub(pc); 467 } 468 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 469 // BugId 4454115: A read from a MappedByteBuffer can fault 470 // here if the underlying file has been truncated. 471 // Do not crash the VM in such a case. 472 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 473 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL; 474 if (nm != NULL && nm->has_unsafe_access()) { 475 stub = StubRoutines::handler_for_unsafe_access(); 476 } 477 } 478 else 479 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 480 // integer divide by zero 481 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 482 } 483 #ifndef AMD64 484 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 485 // floating-point divide by zero 486 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 487 } 488 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 489 // The encoding of D2I in i486.ad can cause an exception prior 490 // to the fist instruction if there was an invalid operation 491 // pending. We want to dismiss that exception. From the win_32 492 // side it also seems that if it really was the fist causing 493 // the exception that we do the d2i by hand with different 494 // rounding. Seems kind of weird. QQQ TODO 495 // Note that we take the exception at the NEXT floating point instruction. 496 if (pc[0] == 0xDB) { 497 assert(pc[0] == 0xDB, "not a FIST opcode"); 498 assert(pc[1] == 0x14, "not a FIST opcode"); 499 assert(pc[2] == 0x24, "not a FIST opcode"); 500 return true; 501 } else { 502 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 503 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 504 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 505 } 506 } 507 else if (sig == SIGFPE ) { 508 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 509 } 510 #endif // !AMD64 511 512 // QQQ It doesn't seem that we need to do this on x86 because we should be able 513 // to return properly from the handler without this extra stuff on the back side. 514 515 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 516 // Determination of interpreter/vtable stub/compiled code null exception 517 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 518 } 519 } 520 521 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 522 // and the heap gets shrunk before the field access. 523 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 524 address addr = JNI_FastGetField::find_slowcase_pc(pc); 525 if (addr != (address)-1) { 526 stub = addr; 527 } 528 } 529 530 // Check to see if we caught the safepoint code in the 531 // process of write protecting the memory serialization page. 532 // It write enables the page immediately after protecting it 533 // so we can just return to retry the write. 534 if ((sig == SIGSEGV) && 535 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 536 // Block current thread until the memory serialize page permission restored. 537 os::block_on_serialize_page_trap(); 538 return true; 539 } 540 } 541 542 // Execution protection violation 543 // 544 // Preventative code for future versions of Solaris which may 545 // enable execution protection when running the 32-bit VM on AMD64. 546 // 547 // This should be kept as the last step in the triage. We don't 548 // have a dedicated trap number for a no-execute fault, so be 549 // conservative and allow other handlers the first shot. 550 // 551 // Note: We don't test that info->si_code == SEGV_ACCERR here. 552 // this si_code is so generic that it is almost meaningless; and 553 // the si_code for this condition may change in the future. 554 // Furthermore, a false-positive should be harmless. 555 if (UnguardOnExecutionViolation > 0 && 556 (sig == SIGSEGV || sig == SIGBUS) && 557 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 558 int page_size = os::vm_page_size(); 559 address addr = (address) info->si_addr; 560 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 561 // Make sure the pc and the faulting address are sane. 562 // 563 // If an instruction spans a page boundary, and the page containing 564 // the beginning of the instruction is executable but the following 565 // page is not, the pc and the faulting address might be slightly 566 // different - we still want to unguard the 2nd page in this case. 567 // 568 // 15 bytes seems to be a (very) safe value for max instruction size. 569 bool pc_is_near_addr = 570 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 571 bool instr_spans_page_boundary = 572 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 573 (intptr_t) page_size) > 0); 574 575 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 576 static volatile address last_addr = 577 (address) os::non_memory_address_word(); 578 579 // In conservative mode, don't unguard unless the address is in the VM 580 if (addr != last_addr && 581 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 582 583 // Make memory rwx and retry 584 address page_start = 585 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 586 bool res = os::protect_memory((char*) page_start, page_size, 587 os::MEM_PROT_RWX); 588 589 if (PrintMiscellaneous && Verbose) { 590 char buf[256]; 591 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 592 "at " INTPTR_FORMAT 593 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 594 page_start, (res ? "success" : "failed"), errno); 595 tty->print_raw_cr(buf); 596 } 597 stub = pc; 598 599 // Set last_addr so if we fault again at the same address, we don't end 600 // up in an endless loop. 601 // 602 // There are two potential complications here. Two threads trapping at 603 // the same address at the same time could cause one of the threads to 604 // think it already unguarded, and abort the VM. Likely very rare. 605 // 606 // The other race involves two threads alternately trapping at 607 // different addresses and failing to unguard the page, resulting in 608 // an endless loop. This condition is probably even more unlikely than 609 // the first. 610 // 611 // Although both cases could be avoided by using locks or thread local 612 // last_addr, these solutions are unnecessary complication: this 613 // handler is a best-effort safety net, not a complete solution. It is 614 // disabled by default and should only be used as a workaround in case 615 // we missed any no-execute-unsafe VM code. 616 617 last_addr = addr; 618 } 619 } 620 } 621 622 if (stub != NULL) { 623 // save all thread context in case we need to restore it 624 625 if (thread != NULL) thread->set_saved_exception_pc(pc); 626 // 12/02/99: On Sparc it appears that the full context is also saved 627 // but as yet, no one looks at or restores that saved context 628 // factor me: setPC 629 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub; 630 return true; 631 } 632 633 // signal-chaining 634 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 635 return true; 636 } 637 638 #ifndef AMD64 639 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 640 // Handle an undefined selector caused by an attempt to assign 641 // fs in libthread getipriptr(). With the current libthread design every 512 642 // thread creations the LDT for a private thread data structure is extended 643 // and thre is a hazard that and another thread attempting a thread creation 644 // will use a stale LDTR that doesn't reflect the structure's growth, 645 // causing a GP fault. 646 // Enforce the probable limit of passes through here to guard against an 647 // infinite loop if some other move to fs caused the GP fault. Note that 648 // this loop counter is ultimately a heuristic as it is possible for 649 // more than one thread to generate this fault at a time in an MP system. 650 // In the case of the loop count being exceeded or if the poll fails 651 // just fall through to a fatal error. 652 // If there is some other source of T_GPFLT traps and the text at EIP is 653 // unreadable this code will loop infinitely until the stack is exausted. 654 // The key to diagnosis in this case is to look for the bottom signal handler 655 // frame. 656 657 if(! IgnoreLibthreadGPFault) { 658 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 659 const unsigned char *p = 660 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 661 662 // Expected instruction? 663 664 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 665 666 Atomic::inc(&ldtr_refresh); 667 668 // Infinite loop? 669 670 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 671 672 // No, force scheduling to get a fresh view of the LDTR 673 674 if(poll(NULL, 0, 10) == 0) { 675 676 // Retry the move 677 678 return false; 679 } 680 } 681 } 682 } 683 } 684 #endif // !AMD64 685 686 if (!abort_if_unrecognized) { 687 // caller wants another chance, so give it to him 688 return false; 689 } 690 691 if (!os::Solaris::libjsig_is_loaded) { 692 struct sigaction oldAct; 693 sigaction(sig, (struct sigaction *)0, &oldAct); 694 if (oldAct.sa_sigaction != signalHandler) { 695 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 696 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 697 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand); 698 } 699 } 700 701 if (pc == NULL && uc != NULL) { 702 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 703 } 704 705 // unmask current signal 706 sigset_t newset; 707 sigemptyset(&newset); 708 sigaddset(&newset, sig); 709 sigprocmask(SIG_UNBLOCK, &newset, NULL); 710 711 VMError err(t, sig, pc, info, ucVoid); 712 err.report_and_die(); 713 714 ShouldNotReachHere(); 715 } 716 717 void os::print_context(outputStream *st, void *context) { 718 if (context == NULL) return; 719 720 ucontext_t *uc = (ucontext_t*)context; 721 st->print_cr("Registers:"); 722 #ifdef AMD64 723 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 724 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 725 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 726 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 727 st->cr(); 728 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 729 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 730 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 731 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 732 st->cr(); 733 st->print(", R8=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 734 st->print(", R9=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 735 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 736 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 737 st->print(", R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 738 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 739 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 740 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 741 st->cr(); 742 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 743 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 744 #else 745 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 746 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 747 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 748 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 749 st->cr(); 750 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 751 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 752 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 753 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 754 st->cr(); 755 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 756 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 757 #endif // AMD64 758 st->cr(); 759 st->cr(); 760 761 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 762 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 763 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 764 st->cr(); 765 766 // Note: it may be unsafe to inspect memory near pc. For example, pc may 767 // point to garbage if entry point in an nmethod is corrupted. Leave 768 // this at the end, and hope for the best. 769 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 770 address pc = epc.pc(); 771 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 772 print_hex_dump(st, pc - 16, pc + 16, sizeof(char)); 773 } 774 775 #ifdef AMD64 776 void os::Solaris::init_thread_fpu_state(void) { 777 // Nothing to do 778 } 779 #else 780 // From solaris_i486.s 781 extern "C" void fixcw(); 782 783 void os::Solaris::init_thread_fpu_state(void) { 784 // Set fpu to 53 bit precision. This happens too early to use a stub. 785 fixcw(); 786 } 787 788 // These routines are the initial value of atomic_xchg_entry(), 789 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 790 // until initialization is complete. 791 // TODO - replace with .il implementation when compiler supports it. 792 793 typedef jint xchg_func_t (jint, volatile jint*); 794 typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 795 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 796 typedef jint add_func_t (jint, volatile jint*); 797 798 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 799 // try to use the stub: 800 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 801 802 if (func != NULL) { 803 os::atomic_xchg_func = func; 804 return (*func)(exchange_value, dest); 805 } 806 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 807 808 jint old_value = *dest; 809 *dest = exchange_value; 810 return old_value; 811 } 812 813 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 814 // try to use the stub: 815 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 816 817 if (func != NULL) { 818 os::atomic_cmpxchg_func = func; 819 return (*func)(exchange_value, dest, compare_value); 820 } 821 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 822 823 jint old_value = *dest; 824 if (old_value == compare_value) 825 *dest = exchange_value; 826 return old_value; 827 } 828 829 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 830 // try to use the stub: 831 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 832 833 if (func != NULL) { 834 os::atomic_cmpxchg_long_func = func; 835 return (*func)(exchange_value, dest, compare_value); 836 } 837 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 838 839 jlong old_value = *dest; 840 if (old_value == compare_value) 841 *dest = exchange_value; 842 return old_value; 843 } 844 845 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 846 // try to use the stub: 847 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 848 849 if (func != NULL) { 850 os::atomic_add_func = func; 851 return (*func)(add_value, dest); 852 } 853 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 854 855 return (*dest) += add_value; 856 } 857 858 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 859 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 860 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 861 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 862 863 extern "C" _solaris_raw_setup_fpu(address ptr); 864 void os::setup_fpu() { 865 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 866 _solaris_raw_setup_fpu(fpu_cntrl); 867 } 868 #endif // AMD64