os_solaris_x86.cpp revision 1983:36c186bcc085
1/* 2 * Copyright (c) 1999, 2010, 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 "assembler_x86.inline.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_solaris.h" 34#include "memory/allocation.inline.hpp" 35#include "mutex_solaris.inline.hpp" 36#include "nativeInst_x86.hpp" 37#include "os_share_solaris.hpp" 38#include "prims/jniFastGetField.hpp" 39#include "prims/jvm.h" 40#include "prims/jvm_misc.hpp" 41#include "runtime/arguments.hpp" 42#include "runtime/extendedPC.hpp" 43#include "runtime/frame.inline.hpp" 44#include "runtime/interfaceSupport.hpp" 45#include "runtime/java.hpp" 46#include "runtime/javaCalls.hpp" 47#include "runtime/mutexLocker.hpp" 48#include "runtime/osThread.hpp" 49#include "runtime/sharedRuntime.hpp" 50#include "runtime/stubRoutines.hpp" 51#include "runtime/timer.hpp" 52#include "thread_solaris.inline.hpp" 53#include "utilities/events.hpp" 54#include "utilities/vmError.hpp" 55#ifdef COMPILER1 56#include "c1/c1_Runtime1.hpp" 57#endif 58#ifdef COMPILER2 59#include "opto/runtime.hpp" 60#endif 61 62// put OS-includes here 63# include <sys/types.h> 64# include <sys/mman.h> 65# include <pthread.h> 66# include <signal.h> 67# include <setjmp.h> 68# include <errno.h> 69# include <dlfcn.h> 70# include <stdio.h> 71# include <unistd.h> 72# include <sys/resource.h> 73# include <thread.h> 74# include <sys/stat.h> 75# include <sys/time.h> 76# include <sys/filio.h> 77# include <sys/utsname.h> 78# include <sys/systeminfo.h> 79# include <sys/socket.h> 80# include <sys/trap.h> 81# include <sys/lwp.h> 82# include <pwd.h> 83# include <poll.h> 84# include <sys/lwp.h> 85# include <procfs.h> // see comment in <sys/procfs.h> 86 87#ifndef AMD64 88// QQQ seems useless at this point 89# define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later 90#endif // AMD64 91# include <sys/procfs.h> // see comment in <sys/procfs.h> 92 93 94#define MAX_PATH (2 * K) 95 96// Minimum stack size for the VM. It's easier to document a constant value 97// but it's different for x86 and sparc because the page sizes are different. 98#ifdef AMD64 99size_t os::Solaris::min_stack_allowed = 224*K; 100#define REG_SP REG_RSP 101#define REG_PC REG_RIP 102#define REG_FP REG_RBP 103#else 104size_t os::Solaris::min_stack_allowed = 64*K; 105#define REG_SP UESP 106#define REG_PC EIP 107#define REG_FP EBP 108// 4900493 counter to prevent runaway LDTR refresh attempt 109 110static volatile int ldtr_refresh = 0; 111// the libthread instruction that faults because of the stale LDTR 112 113static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs 114 }; 115#endif // AMD64 116 117char* os::non_memory_address_word() { 118 // Must never look like an address returned by reserve_memory, 119 // even in its subfields (as defined by the CPU immediate fields, 120 // if the CPU splits constants across multiple instructions). 121 return (char*) -1; 122} 123 124// 125// Validate a ucontext retrieved from walking a uc_link of a ucontext. 126// There are issues with libthread giving out uc_links for different threads 127// on the same uc_link chain and bad or circular links. 128// 129bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) { 130 if (valid >= suspect || 131 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags || 132 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp || 133 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) { 134 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");) 135 return false; 136 } 137 138 if (thread->is_Java_thread()) { 139 if (!valid_stack_address(thread, (address)suspect)) { 140 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");) 141 return false; 142 } 143 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) { 144 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");) 145 return false; 146 } 147 } 148 return true; 149} 150 151// We will only follow one level of uc_link since there are libthread 152// issues with ucontext linking and it is better to be safe and just 153// let caller retry later. 154ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread, 155 ucontext_t *uc) { 156 157 ucontext_t *retuc = NULL; 158 159 if (uc != NULL) { 160 if (uc->uc_link == NULL) { 161 // cannot validate without uc_link so accept current ucontext 162 retuc = uc; 163 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 164 // first ucontext is valid so try the next one 165 uc = uc->uc_link; 166 if (uc->uc_link == NULL) { 167 // cannot validate without uc_link so accept current ucontext 168 retuc = uc; 169 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 170 // the ucontext one level down is also valid so return it 171 retuc = uc; 172 } 173 } 174 } 175 return retuc; 176} 177 178// Assumes ucontext is valid 179ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) { 180 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]); 181} 182 183// Assumes ucontext is valid 184intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) { 185 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP]; 186} 187 188// Assumes ucontext is valid 189intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) { 190 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP]; 191} 192 193// For Forte Analyzer AsyncGetCallTrace profiling support - thread 194// is currently interrupted by SIGPROF. 195// 196// The difference between this and os::fetch_frame_from_context() is that 197// here we try to skip nested signal frames. 198ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread, 199 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 200 201 assert(thread != NULL, "just checking"); 202 assert(ret_sp != NULL, "just checking"); 203 assert(ret_fp != NULL, "just checking"); 204 205 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc); 206 return os::fetch_frame_from_context(luc, ret_sp, ret_fp); 207} 208 209ExtendedPC os::fetch_frame_from_context(void* ucVoid, 210 intptr_t** ret_sp, intptr_t** ret_fp) { 211 212 ExtendedPC epc; 213 ucontext_t *uc = (ucontext_t*)ucVoid; 214 215 if (uc != NULL) { 216 epc = os::Solaris::ucontext_get_ExtendedPC(uc); 217 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc); 218 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc); 219 } else { 220 // construct empty ExtendedPC for return value checking 221 epc = ExtendedPC(NULL); 222 if (ret_sp) *ret_sp = (intptr_t *)NULL; 223 if (ret_fp) *ret_fp = (intptr_t *)NULL; 224 } 225 226 return epc; 227} 228 229frame os::fetch_frame_from_context(void* ucVoid) { 230 intptr_t* sp; 231 intptr_t* fp; 232 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 233 return frame(sp, fp, epc.pc()); 234} 235 236frame os::get_sender_for_C_frame(frame* fr) { 237 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 238} 239 240extern "C" intptr_t *_get_current_fp(); // in .il file 241 242frame os::current_frame() { 243 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp 244 frame myframe((intptr_t*)os::current_stack_pointer(), 245 (intptr_t*)fp, 246 CAST_FROM_FN_PTR(address, os::current_frame)); 247 if (os::is_first_C_frame(&myframe)) { 248 // stack is not walkable 249 frame ret; // This will be a null useless frame 250 return ret; 251 } else { 252 return os::get_sender_for_C_frame(&myframe); 253 } 254} 255 256// This is a simple callback that just fetches a PC for an interrupted thread. 257// The thread need not be suspended and the fetched PC is just a hint. 258// This one is currently used for profiling the VMThread ONLY! 259 260// Must be synchronous 261void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) { 262 Thread* thread = args->thread(); 263 ucontext_t* uc = args->ucontext(); 264 intptr_t* sp; 265 266 assert(ProfileVM && thread->is_VM_thread(), "just checking"); 267 268 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]); 269 _addr = new_addr; 270} 271 272static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) { 273 char lwpstatusfile[PROCFILE_LENGTH]; 274 int lwpfd, err; 275 276 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs)) 277 return (err); 278 if (*flags == TRS_LWPID) { 279 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(), 280 *lwp); 281 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) { 282 perror("thr_mutator_status: open lwpstatus"); 283 return (EINVAL); 284 } 285 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) != 286 sizeof (lwpstatus_t)) { 287 perror("thr_mutator_status: read lwpstatus"); 288 (void) close(lwpfd); 289 return (EINVAL); 290 } 291 (void) close(lwpfd); 292 } 293 return (0); 294} 295 296#ifndef AMD64 297 298// Detecting SSE support by OS 299// From solaris_i486.s 300extern "C" bool sse_check(); 301extern "C" bool sse_unavailable(); 302 303enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 304static int sse_status = SSE_UNKNOWN; 305 306 307static void check_for_sse_support() { 308 if (!VM_Version::supports_sse()) { 309 sse_status = SSE_NOT_SUPPORTED; 310 return; 311 } 312 // looking for _sse_hw in libc.so, if it does not exist or 313 // the value (int) is 0, OS has no support for SSE 314 int *sse_hwp; 315 void *h; 316 317 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 318 //open failed, presume no support for SSE 319 sse_status = SSE_NOT_SUPPORTED; 320 return; 321 } 322 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 323 sse_status = SSE_NOT_SUPPORTED; 324 } else if (*sse_hwp == 0) { 325 sse_status = SSE_NOT_SUPPORTED; 326 } 327 dlclose(h); 328 329 if (sse_status == SSE_UNKNOWN) { 330 bool (*try_sse)() = (bool (*)())sse_check; 331 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 332 } 333 334} 335 336#endif // AMD64 337 338bool os::supports_sse() { 339#ifdef AMD64 340 return true; 341#else 342 if (sse_status == SSE_UNKNOWN) 343 check_for_sse_support(); 344 return sse_status == SSE_SUPPORTED; 345#endif // AMD64 346} 347 348bool os::is_allocatable(size_t bytes) { 349#ifdef AMD64 350 return true; 351#else 352 353 if (bytes < 2 * G) { 354 return true; 355 } 356 357 char* addr = reserve_memory(bytes, NULL); 358 359 if (addr != NULL) { 360 release_memory(addr, bytes); 361 } 362 363 return addr != NULL; 364#endif // AMD64 365 366} 367 368extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized); 369 370extern "C" void Fetch32PFI () ; 371extern "C" void Fetch32Resume () ; 372#ifdef AMD64 373extern "C" void FetchNPFI () ; 374extern "C" void FetchNResume () ; 375#endif // AMD64 376 377int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) { 378 ucontext_t* uc = (ucontext_t*) ucVoid; 379 380#ifndef AMD64 381 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 382 // the SSE instruction faulted. supports_sse() need return false. 383 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 384 return true; 385 } 386#endif // !AMD64 387 388 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady 389 390 SignalHandlerMark shm(t); 391 392 if(sig == SIGPIPE || sig == SIGXFSZ) { 393 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 394 return true; 395 } else { 396 if (PrintMiscellaneous && (WizardMode || Verbose)) { 397 char buf[64]; 398 warning("Ignoring %s - see 4229104 or 6499219", 399 os::exception_name(sig, buf, sizeof(buf))); 400 401 } 402 return true; 403 } 404 } 405 406 JavaThread* thread = NULL; 407 VMThread* vmthread = NULL; 408 409 if (os::Solaris::signal_handlers_are_installed) { 410 if (t != NULL ){ 411 if(t->is_Java_thread()) { 412 thread = (JavaThread*)t; 413 } 414 else if(t->is_VM_thread()){ 415 vmthread = (VMThread *)t; 416 } 417 } 418 } 419 420 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs"); 421 422 if (sig == os::Solaris::SIGasync()) { 423 if(thread){ 424 OSThread::InterruptArguments args(thread, uc); 425 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 426 return true; 427 } 428 else if(vmthread){ 429 OSThread::InterruptArguments args(vmthread, uc); 430 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 431 return true; 432 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 433 return true; 434 } else { 435 // If os::Solaris::SIGasync not chained, and this is a non-vm and 436 // non-java thread 437 return true; 438 } 439 } 440 441 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 442 // can't decode this kind of signal 443 info = NULL; 444 } else { 445 assert(sig == info->si_signo, "bad siginfo"); 446 } 447 448 // decide if this trap can be handled by a stub 449 address stub = NULL; 450 451 address pc = NULL; 452 453 //%note os_trap_1 454 if (info != NULL && uc != NULL && thread != NULL) { 455 // factor me: getPCfromContext 456 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 457 458 // SafeFetch32() support 459 if (pc == (address) Fetch32PFI) { 460 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ; 461 return true ; 462 } 463#ifdef AMD64 464 if (pc == (address) FetchNPFI) { 465 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ; 466 return true ; 467 } 468#endif // AMD64 469 470 // Handle ALL stack overflow variations here 471 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 472 address addr = (address) info->si_addr; 473 if (thread->in_stack_yellow_zone(addr)) { 474 thread->disable_stack_yellow_zone(); 475 if (thread->thread_state() == _thread_in_Java) { 476 // Throw a stack overflow exception. Guard pages will be reenabled 477 // while unwinding the stack. 478 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 479 } else { 480 // Thread was in the vm or native code. Return and try to finish. 481 return true; 482 } 483 } else if (thread->in_stack_red_zone(addr)) { 484 // Fatal red zone violation. Disable the guard pages and fall through 485 // to handle_unexpected_exception way down below. 486 thread->disable_stack_red_zone(); 487 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 488 } 489 } 490 491 if (thread->thread_state() == _thread_in_vm) { 492 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 493 stub = StubRoutines::handler_for_unsafe_access(); 494 } 495 } 496 497 if (thread->thread_state() == _thread_in_Java) { 498 // Support Safepoint Polling 499 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 500 stub = SharedRuntime::get_poll_stub(pc); 501 } 502 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 503 // BugId 4454115: A read from a MappedByteBuffer can fault 504 // here if the underlying file has been truncated. 505 // Do not crash the VM in such a case. 506 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 507 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL; 508 if (nm != NULL && nm->has_unsafe_access()) { 509 stub = StubRoutines::handler_for_unsafe_access(); 510 } 511 } 512 else 513 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 514 // integer divide by zero 515 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 516 } 517#ifndef AMD64 518 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 519 // floating-point divide by zero 520 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 521 } 522 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 523 // The encoding of D2I in i486.ad can cause an exception prior 524 // to the fist instruction if there was an invalid operation 525 // pending. We want to dismiss that exception. From the win_32 526 // side it also seems that if it really was the fist causing 527 // the exception that we do the d2i by hand with different 528 // rounding. Seems kind of weird. QQQ TODO 529 // Note that we take the exception at the NEXT floating point instruction. 530 if (pc[0] == 0xDB) { 531 assert(pc[0] == 0xDB, "not a FIST opcode"); 532 assert(pc[1] == 0x14, "not a FIST opcode"); 533 assert(pc[2] == 0x24, "not a FIST opcode"); 534 return true; 535 } else { 536 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 537 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 538 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 539 } 540 } 541 else if (sig == SIGFPE ) { 542 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 543 } 544#endif // !AMD64 545 546 // QQQ It doesn't seem that we need to do this on x86 because we should be able 547 // to return properly from the handler without this extra stuff on the back side. 548 549 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 550 // Determination of interpreter/vtable stub/compiled code null exception 551 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 552 } 553 } 554 555 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 556 // and the heap gets shrunk before the field access. 557 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 558 address addr = JNI_FastGetField::find_slowcase_pc(pc); 559 if (addr != (address)-1) { 560 stub = addr; 561 } 562 } 563 564 // Check to see if we caught the safepoint code in the 565 // process of write protecting the memory serialization page. 566 // It write enables the page immediately after protecting it 567 // so we can just return to retry the write. 568 if ((sig == SIGSEGV) && 569 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 570 // Block current thread until the memory serialize page permission restored. 571 os::block_on_serialize_page_trap(); 572 return true; 573 } 574 } 575 576 // Execution protection violation 577 // 578 // Preventative code for future versions of Solaris which may 579 // enable execution protection when running the 32-bit VM on AMD64. 580 // 581 // This should be kept as the last step in the triage. We don't 582 // have a dedicated trap number for a no-execute fault, so be 583 // conservative and allow other handlers the first shot. 584 // 585 // Note: We don't test that info->si_code == SEGV_ACCERR here. 586 // this si_code is so generic that it is almost meaningless; and 587 // the si_code for this condition may change in the future. 588 // Furthermore, a false-positive should be harmless. 589 if (UnguardOnExecutionViolation > 0 && 590 (sig == SIGSEGV || sig == SIGBUS) && 591 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 592 int page_size = os::vm_page_size(); 593 address addr = (address) info->si_addr; 594 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 595 // Make sure the pc and the faulting address are sane. 596 // 597 // If an instruction spans a page boundary, and the page containing 598 // the beginning of the instruction is executable but the following 599 // page is not, the pc and the faulting address might be slightly 600 // different - we still want to unguard the 2nd page in this case. 601 // 602 // 15 bytes seems to be a (very) safe value for max instruction size. 603 bool pc_is_near_addr = 604 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 605 bool instr_spans_page_boundary = 606 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 607 (intptr_t) page_size) > 0); 608 609 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 610 static volatile address last_addr = 611 (address) os::non_memory_address_word(); 612 613 // In conservative mode, don't unguard unless the address is in the VM 614 if (addr != last_addr && 615 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 616 617 // Make memory rwx and retry 618 address page_start = 619 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 620 bool res = os::protect_memory((char*) page_start, page_size, 621 os::MEM_PROT_RWX); 622 623 if (PrintMiscellaneous && Verbose) { 624 char buf[256]; 625 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 626 "at " INTPTR_FORMAT 627 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 628 page_start, (res ? "success" : "failed"), errno); 629 tty->print_raw_cr(buf); 630 } 631 stub = pc; 632 633 // Set last_addr so if we fault again at the same address, we don't end 634 // up in an endless loop. 635 // 636 // There are two potential complications here. Two threads trapping at 637 // the same address at the same time could cause one of the threads to 638 // think it already unguarded, and abort the VM. Likely very rare. 639 // 640 // The other race involves two threads alternately trapping at 641 // different addresses and failing to unguard the page, resulting in 642 // an endless loop. This condition is probably even more unlikely than 643 // the first. 644 // 645 // Although both cases could be avoided by using locks or thread local 646 // last_addr, these solutions are unnecessary complication: this 647 // handler is a best-effort safety net, not a complete solution. It is 648 // disabled by default and should only be used as a workaround in case 649 // we missed any no-execute-unsafe VM code. 650 651 last_addr = addr; 652 } 653 } 654 } 655 656 if (stub != NULL) { 657 // save all thread context in case we need to restore it 658 659 if (thread != NULL) thread->set_saved_exception_pc(pc); 660 // 12/02/99: On Sparc it appears that the full context is also saved 661 // but as yet, no one looks at or restores that saved context 662 // factor me: setPC 663 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub; 664 return true; 665 } 666 667 // signal-chaining 668 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 669 return true; 670 } 671 672#ifndef AMD64 673 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 674 // Handle an undefined selector caused by an attempt to assign 675 // fs in libthread getipriptr(). With the current libthread design every 512 676 // thread creations the LDT for a private thread data structure is extended 677 // and thre is a hazard that and another thread attempting a thread creation 678 // will use a stale LDTR that doesn't reflect the structure's growth, 679 // causing a GP fault. 680 // Enforce the probable limit of passes through here to guard against an 681 // infinite loop if some other move to fs caused the GP fault. Note that 682 // this loop counter is ultimately a heuristic as it is possible for 683 // more than one thread to generate this fault at a time in an MP system. 684 // In the case of the loop count being exceeded or if the poll fails 685 // just fall through to a fatal error. 686 // If there is some other source of T_GPFLT traps and the text at EIP is 687 // unreadable this code will loop infinitely until the stack is exausted. 688 // The key to diagnosis in this case is to look for the bottom signal handler 689 // frame. 690 691 if(! IgnoreLibthreadGPFault) { 692 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 693 const unsigned char *p = 694 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 695 696 // Expected instruction? 697 698 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 699 700 Atomic::inc(&ldtr_refresh); 701 702 // Infinite loop? 703 704 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 705 706 // No, force scheduling to get a fresh view of the LDTR 707 708 if(poll(NULL, 0, 10) == 0) { 709 710 // Retry the move 711 712 return false; 713 } 714 } 715 } 716 } 717 } 718#endif // !AMD64 719 720 if (!abort_if_unrecognized) { 721 // caller wants another chance, so give it to him 722 return false; 723 } 724 725 if (!os::Solaris::libjsig_is_loaded) { 726 struct sigaction oldAct; 727 sigaction(sig, (struct sigaction *)0, &oldAct); 728 if (oldAct.sa_sigaction != signalHandler) { 729 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 730 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 731 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand); 732 } 733 } 734 735 if (pc == NULL && uc != NULL) { 736 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 737 } 738 739 // unmask current signal 740 sigset_t newset; 741 sigemptyset(&newset); 742 sigaddset(&newset, sig); 743 sigprocmask(SIG_UNBLOCK, &newset, NULL); 744 745 // Determine which sort of error to throw. Out of swap may signal 746 // on the thread stack, which could get a mapping error when touched. 747 address addr = (address) info->si_addr; 748 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) { 749 vm_exit_out_of_memory(0, "Out of swap space to map in thread stack."); 750 } 751 752 VMError err(t, sig, pc, info, ucVoid); 753 err.report_and_die(); 754 755 ShouldNotReachHere(); 756} 757 758void os::print_context(outputStream *st, void *context) { 759 if (context == NULL) return; 760 761 ucontext_t *uc = (ucontext_t*)context; 762 st->print_cr("Registers:"); 763#ifdef AMD64 764 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 765 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 766 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 767 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 768 st->cr(); 769 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 770 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 771 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 772 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 773 st->cr(); 774 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 775 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 776 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 777 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 778 st->cr(); 779 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 780 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 781 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 782 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 783 st->cr(); 784 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 785 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 786#else 787 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 788 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 789 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 790 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 791 st->cr(); 792 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 793 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 794 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 795 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 796 st->cr(); 797 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 798 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 799#endif // AMD64 800 st->cr(); 801 st->cr(); 802 803 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 804 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 805 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 806 st->cr(); 807 808 // Note: it may be unsafe to inspect memory near pc. For example, pc may 809 // point to garbage if entry point in an nmethod is corrupted. Leave 810 // this at the end, and hope for the best. 811 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 812 address pc = epc.pc(); 813 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 814 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 815} 816 817void os::print_register_info(outputStream *st, void *context) { 818 if (context == NULL) return; 819 820 ucontext_t *uc = (ucontext_t*)context; 821 822 st->print_cr("Register to memory mapping:"); 823 st->cr(); 824 825 // this is horrendously verbose but the layout of the registers in the 826 // context does not match how we defined our abstract Register set, so 827 // we can't just iterate through the gregs area 828 829 // this is only for the "general purpose" registers 830 831#ifdef AMD64 832 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]); 833 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]); 834 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]); 835 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]); 836 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]); 837 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]); 838 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]); 839 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]); 840 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]); 841 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]); 842 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]); 843 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]); 844 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]); 845 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]); 846 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]); 847 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]); 848#else 849 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]); 850 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]); 851 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]); 852 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]); 853 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]); 854 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]); 855 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]); 856 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]); 857#endif 858 859 st->cr(); 860} 861 862 863#ifdef AMD64 864void os::Solaris::init_thread_fpu_state(void) { 865 // Nothing to do 866} 867#else 868// From solaris_i486.s 869extern "C" void fixcw(); 870 871void os::Solaris::init_thread_fpu_state(void) { 872 // Set fpu to 53 bit precision. This happens too early to use a stub. 873 fixcw(); 874} 875 876// These routines are the initial value of atomic_xchg_entry(), 877// atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 878// until initialization is complete. 879// TODO - replace with .il implementation when compiler supports it. 880 881typedef jint xchg_func_t (jint, volatile jint*); 882typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 883typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 884typedef jint add_func_t (jint, volatile jint*); 885 886jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 887 // try to use the stub: 888 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 889 890 if (func != NULL) { 891 os::atomic_xchg_func = func; 892 return (*func)(exchange_value, dest); 893 } 894 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 895 896 jint old_value = *dest; 897 *dest = exchange_value; 898 return old_value; 899} 900 901jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 902 // try to use the stub: 903 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 904 905 if (func != NULL) { 906 os::atomic_cmpxchg_func = func; 907 return (*func)(exchange_value, dest, compare_value); 908 } 909 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 910 911 jint old_value = *dest; 912 if (old_value == compare_value) 913 *dest = exchange_value; 914 return old_value; 915} 916 917jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 918 // try to use the stub: 919 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 920 921 if (func != NULL) { 922 os::atomic_cmpxchg_long_func = func; 923 return (*func)(exchange_value, dest, compare_value); 924 } 925 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 926 927 jlong old_value = *dest; 928 if (old_value == compare_value) 929 *dest = exchange_value; 930 return old_value; 931} 932 933jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 934 // try to use the stub: 935 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 936 937 if (func != NULL) { 938 os::atomic_add_func = func; 939 return (*func)(add_value, dest); 940 } 941 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 942 943 return (*dest) += add_value; 944} 945 946xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 947cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 948cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 949add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 950 951extern "C" void _solaris_raw_setup_fpu(address ptr); 952void os::setup_fpu() { 953 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 954 _solaris_raw_setup_fpu(fpu_cntrl); 955} 956#endif // AMD64 957