os_solaris_x86.cpp revision 3171:da4be62fb889
1/* 2 * Copyright (c) 1999, 2011, 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_sp(); // in .il file 241 242address os::current_stack_pointer() { 243 return (address)_get_current_sp(); 244} 245 246extern "C" intptr_t *_get_current_fp(); // in .il file 247 248frame os::current_frame() { 249 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp 250 frame myframe((intptr_t*)os::current_stack_pointer(), 251 (intptr_t*)fp, 252 CAST_FROM_FN_PTR(address, os::current_frame)); 253 if (os::is_first_C_frame(&myframe)) { 254 // stack is not walkable 255 frame ret; // This will be a null useless frame 256 return ret; 257 } else { 258 return os::get_sender_for_C_frame(&myframe); 259 } 260} 261 262// This is a simple callback that just fetches a PC for an interrupted thread. 263// The thread need not be suspended and the fetched PC is just a hint. 264// This one is currently used for profiling the VMThread ONLY! 265 266// Must be synchronous 267void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) { 268 Thread* thread = args->thread(); 269 ucontext_t* uc = args->ucontext(); 270 intptr_t* sp; 271 272 assert(ProfileVM && thread->is_VM_thread(), "just checking"); 273 274 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]); 275 _addr = new_addr; 276} 277 278static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) { 279 char lwpstatusfile[PROCFILE_LENGTH]; 280 int lwpfd, err; 281 282 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs)) 283 return (err); 284 if (*flags == TRS_LWPID) { 285 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(), 286 *lwp); 287 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) { 288 perror("thr_mutator_status: open lwpstatus"); 289 return (EINVAL); 290 } 291 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) != 292 sizeof (lwpstatus_t)) { 293 perror("thr_mutator_status: read lwpstatus"); 294 (void) close(lwpfd); 295 return (EINVAL); 296 } 297 (void) close(lwpfd); 298 } 299 return (0); 300} 301 302#ifndef AMD64 303 304// Detecting SSE support by OS 305// From solaris_i486.s 306extern "C" bool sse_check(); 307extern "C" bool sse_unavailable(); 308 309enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 310static int sse_status = SSE_UNKNOWN; 311 312 313static void check_for_sse_support() { 314 if (!VM_Version::supports_sse()) { 315 sse_status = SSE_NOT_SUPPORTED; 316 return; 317 } 318 // looking for _sse_hw in libc.so, if it does not exist or 319 // the value (int) is 0, OS has no support for SSE 320 int *sse_hwp; 321 void *h; 322 323 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 324 //open failed, presume no support for SSE 325 sse_status = SSE_NOT_SUPPORTED; 326 return; 327 } 328 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 329 sse_status = SSE_NOT_SUPPORTED; 330 } else if (*sse_hwp == 0) { 331 sse_status = SSE_NOT_SUPPORTED; 332 } 333 dlclose(h); 334 335 if (sse_status == SSE_UNKNOWN) { 336 bool (*try_sse)() = (bool (*)())sse_check; 337 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 338 } 339 340} 341 342#endif // AMD64 343 344bool os::supports_sse() { 345#ifdef AMD64 346 return true; 347#else 348 if (sse_status == SSE_UNKNOWN) 349 check_for_sse_support(); 350 return sse_status == SSE_SUPPORTED; 351#endif // AMD64 352} 353 354bool os::is_allocatable(size_t bytes) { 355#ifdef AMD64 356 return true; 357#else 358 359 if (bytes < 2 * G) { 360 return true; 361 } 362 363 char* addr = reserve_memory(bytes, NULL); 364 365 if (addr != NULL) { 366 release_memory(addr, bytes); 367 } 368 369 return addr != NULL; 370#endif // AMD64 371 372} 373 374extern "C" void Fetch32PFI () ; 375extern "C" void Fetch32Resume () ; 376#ifdef AMD64 377extern "C" void FetchNPFI () ; 378extern "C" void FetchNResume () ; 379#endif // AMD64 380 381extern "C" JNIEXPORT int 382JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, 383 int abort_if_unrecognized) { 384 ucontext_t* uc = (ucontext_t*) ucVoid; 385 386#ifndef AMD64 387 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 388 // the SSE instruction faulted. supports_sse() need return false. 389 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 390 return true; 391 } 392#endif // !AMD64 393 394 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady 395 396 SignalHandlerMark shm(t); 397 398 if(sig == SIGPIPE || sig == SIGXFSZ) { 399 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 400 return true; 401 } else { 402 if (PrintMiscellaneous && (WizardMode || Verbose)) { 403 char buf[64]; 404 warning("Ignoring %s - see 4229104 or 6499219", 405 os::exception_name(sig, buf, sizeof(buf))); 406 407 } 408 return true; 409 } 410 } 411 412 JavaThread* thread = NULL; 413 VMThread* vmthread = NULL; 414 415 if (os::Solaris::signal_handlers_are_installed) { 416 if (t != NULL ){ 417 if(t->is_Java_thread()) { 418 thread = (JavaThread*)t; 419 } 420 else if(t->is_VM_thread()){ 421 vmthread = (VMThread *)t; 422 } 423 } 424 } 425 426 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs"); 427 428 if (sig == os::Solaris::SIGasync()) { 429 if(thread){ 430 OSThread::InterruptArguments args(thread, uc); 431 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 432 return true; 433 } 434 else if(vmthread){ 435 OSThread::InterruptArguments args(vmthread, uc); 436 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args); 437 return true; 438 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 439 return true; 440 } else { 441 // If os::Solaris::SIGasync not chained, and this is a non-vm and 442 // non-java thread 443 return true; 444 } 445 } 446 447 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 448 // can't decode this kind of signal 449 info = NULL; 450 } else { 451 assert(sig == info->si_signo, "bad siginfo"); 452 } 453 454 // decide if this trap can be handled by a stub 455 address stub = NULL; 456 457 address pc = NULL; 458 459 //%note os_trap_1 460 if (info != NULL && uc != NULL && thread != NULL) { 461 // factor me: getPCfromContext 462 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 463 464 // SafeFetch32() support 465 if (pc == (address) Fetch32PFI) { 466 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ; 467 return true ; 468 } 469#ifdef AMD64 470 if (pc == (address) FetchNPFI) { 471 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ; 472 return true ; 473 } 474#endif // AMD64 475 476 // Handle ALL stack overflow variations here 477 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 478 address addr = (address) info->si_addr; 479 if (thread->in_stack_yellow_zone(addr)) { 480 thread->disable_stack_yellow_zone(); 481 if (thread->thread_state() == _thread_in_Java) { 482 // Throw a stack overflow exception. Guard pages will be reenabled 483 // while unwinding the stack. 484 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 485 } else { 486 // Thread was in the vm or native code. Return and try to finish. 487 return true; 488 } 489 } else if (thread->in_stack_red_zone(addr)) { 490 // Fatal red zone violation. Disable the guard pages and fall through 491 // to handle_unexpected_exception way down below. 492 thread->disable_stack_red_zone(); 493 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 494 } 495 } 496 497 if (thread->thread_state() == _thread_in_vm) { 498 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 499 stub = StubRoutines::handler_for_unsafe_access(); 500 } 501 } 502 503 if (thread->thread_state() == _thread_in_Java) { 504 // Support Safepoint Polling 505 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 506 stub = SharedRuntime::get_poll_stub(pc); 507 } 508 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 509 // BugId 4454115: A read from a MappedByteBuffer can fault 510 // here if the underlying file has been truncated. 511 // Do not crash the VM in such a case. 512 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 513 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL; 514 if (nm != NULL && nm->has_unsafe_access()) { 515 stub = StubRoutines::handler_for_unsafe_access(); 516 } 517 } 518 else 519 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 520 // integer divide by zero 521 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 522 } 523#ifndef AMD64 524 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 525 // floating-point divide by zero 526 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 527 } 528 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 529 // The encoding of D2I in i486.ad can cause an exception prior 530 // to the fist instruction if there was an invalid operation 531 // pending. We want to dismiss that exception. From the win_32 532 // side it also seems that if it really was the fist causing 533 // the exception that we do the d2i by hand with different 534 // rounding. Seems kind of weird. QQQ TODO 535 // Note that we take the exception at the NEXT floating point instruction. 536 if (pc[0] == 0xDB) { 537 assert(pc[0] == 0xDB, "not a FIST opcode"); 538 assert(pc[1] == 0x14, "not a FIST opcode"); 539 assert(pc[2] == 0x24, "not a FIST opcode"); 540 return true; 541 } else { 542 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 543 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 544 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 545 } 546 } 547 else if (sig == SIGFPE ) { 548 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 549 } 550#endif // !AMD64 551 552 // QQQ It doesn't seem that we need to do this on x86 because we should be able 553 // to return properly from the handler without this extra stuff on the back side. 554 555 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 556 // Determination of interpreter/vtable stub/compiled code null exception 557 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 558 } 559 } 560 561 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 562 // and the heap gets shrunk before the field access. 563 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 564 address addr = JNI_FastGetField::find_slowcase_pc(pc); 565 if (addr != (address)-1) { 566 stub = addr; 567 } 568 } 569 570 // Check to see if we caught the safepoint code in the 571 // process of write protecting the memory serialization page. 572 // It write enables the page immediately after protecting it 573 // so we can just return to retry the write. 574 if ((sig == SIGSEGV) && 575 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 576 // Block current thread until the memory serialize page permission restored. 577 os::block_on_serialize_page_trap(); 578 return true; 579 } 580 } 581 582 // Execution protection violation 583 // 584 // Preventative code for future versions of Solaris which may 585 // enable execution protection when running the 32-bit VM on AMD64. 586 // 587 // This should be kept as the last step in the triage. We don't 588 // have a dedicated trap number for a no-execute fault, so be 589 // conservative and allow other handlers the first shot. 590 // 591 // Note: We don't test that info->si_code == SEGV_ACCERR here. 592 // this si_code is so generic that it is almost meaningless; and 593 // the si_code for this condition may change in the future. 594 // Furthermore, a false-positive should be harmless. 595 if (UnguardOnExecutionViolation > 0 && 596 (sig == SIGSEGV || sig == SIGBUS) && 597 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 598 int page_size = os::vm_page_size(); 599 address addr = (address) info->si_addr; 600 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 601 // Make sure the pc and the faulting address are sane. 602 // 603 // If an instruction spans a page boundary, and the page containing 604 // the beginning of the instruction is executable but the following 605 // page is not, the pc and the faulting address might be slightly 606 // different - we still want to unguard the 2nd page in this case. 607 // 608 // 15 bytes seems to be a (very) safe value for max instruction size. 609 bool pc_is_near_addr = 610 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 611 bool instr_spans_page_boundary = 612 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 613 (intptr_t) page_size) > 0); 614 615 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 616 static volatile address last_addr = 617 (address) os::non_memory_address_word(); 618 619 // In conservative mode, don't unguard unless the address is in the VM 620 if (addr != last_addr && 621 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 622 623 // Make memory rwx and retry 624 address page_start = 625 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 626 bool res = os::protect_memory((char*) page_start, page_size, 627 os::MEM_PROT_RWX); 628 629 if (PrintMiscellaneous && Verbose) { 630 char buf[256]; 631 jio_snprintf(buf, sizeof(buf), "Execution protection violation " 632 "at " INTPTR_FORMAT 633 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, 634 page_start, (res ? "success" : "failed"), errno); 635 tty->print_raw_cr(buf); 636 } 637 stub = pc; 638 639 // Set last_addr so if we fault again at the same address, we don't end 640 // up in an endless loop. 641 // 642 // There are two potential complications here. Two threads trapping at 643 // the same address at the same time could cause one of the threads to 644 // think it already unguarded, and abort the VM. Likely very rare. 645 // 646 // The other race involves two threads alternately trapping at 647 // different addresses and failing to unguard the page, resulting in 648 // an endless loop. This condition is probably even more unlikely than 649 // the first. 650 // 651 // Although both cases could be avoided by using locks or thread local 652 // last_addr, these solutions are unnecessary complication: this 653 // handler is a best-effort safety net, not a complete solution. It is 654 // disabled by default and should only be used as a workaround in case 655 // we missed any no-execute-unsafe VM code. 656 657 last_addr = addr; 658 } 659 } 660 } 661 662 if (stub != NULL) { 663 // save all thread context in case we need to restore it 664 665 if (thread != NULL) thread->set_saved_exception_pc(pc); 666 // 12/02/99: On Sparc it appears that the full context is also saved 667 // but as yet, no one looks at or restores that saved context 668 // factor me: setPC 669 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub; 670 return true; 671 } 672 673 // signal-chaining 674 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 675 return true; 676 } 677 678#ifndef AMD64 679 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 680 // Handle an undefined selector caused by an attempt to assign 681 // fs in libthread getipriptr(). With the current libthread design every 512 682 // thread creations the LDT for a private thread data structure is extended 683 // and thre is a hazard that and another thread attempting a thread creation 684 // will use a stale LDTR that doesn't reflect the structure's growth, 685 // causing a GP fault. 686 // Enforce the probable limit of passes through here to guard against an 687 // infinite loop if some other move to fs caused the GP fault. Note that 688 // this loop counter is ultimately a heuristic as it is possible for 689 // more than one thread to generate this fault at a time in an MP system. 690 // In the case of the loop count being exceeded or if the poll fails 691 // just fall through to a fatal error. 692 // If there is some other source of T_GPFLT traps and the text at EIP is 693 // unreadable this code will loop infinitely until the stack is exausted. 694 // The key to diagnosis in this case is to look for the bottom signal handler 695 // frame. 696 697 if(! IgnoreLibthreadGPFault) { 698 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 699 const unsigned char *p = 700 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 701 702 // Expected instruction? 703 704 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 705 706 Atomic::inc(&ldtr_refresh); 707 708 // Infinite loop? 709 710 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 711 712 // No, force scheduling to get a fresh view of the LDTR 713 714 if(poll(NULL, 0, 10) == 0) { 715 716 // Retry the move 717 718 return false; 719 } 720 } 721 } 722 } 723 } 724#endif // !AMD64 725 726 if (!abort_if_unrecognized) { 727 // caller wants another chance, so give it to him 728 return false; 729 } 730 731 if (!os::Solaris::libjsig_is_loaded) { 732 struct sigaction oldAct; 733 sigaction(sig, (struct sigaction *)0, &oldAct); 734 if (oldAct.sa_sigaction != signalHandler) { 735 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 736 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 737 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand); 738 } 739 } 740 741 if (pc == NULL && uc != NULL) { 742 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 743 } 744 745 // unmask current signal 746 sigset_t newset; 747 sigemptyset(&newset); 748 sigaddset(&newset, sig); 749 sigprocmask(SIG_UNBLOCK, &newset, NULL); 750 751 // Determine which sort of error to throw. Out of swap may signal 752 // on the thread stack, which could get a mapping error when touched. 753 address addr = (address) info->si_addr; 754 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) { 755 vm_exit_out_of_memory(0, "Out of swap space to map in thread stack."); 756 } 757 758 VMError err(t, sig, pc, info, ucVoid); 759 err.report_and_die(); 760 761 ShouldNotReachHere(); 762} 763 764void os::print_context(outputStream *st, void *context) { 765 if (context == NULL) return; 766 767 ucontext_t *uc = (ucontext_t*)context; 768 st->print_cr("Registers:"); 769#ifdef AMD64 770 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 771 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 772 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 773 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 774 st->cr(); 775 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 776 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 777 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 778 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 779 st->cr(); 780 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 781 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 782 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 783 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 784 st->cr(); 785 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 786 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 787 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 788 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 789 st->cr(); 790 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 791 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 792#else 793 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 794 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 795 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 796 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 797 st->cr(); 798 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 799 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 800 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 801 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 802 st->cr(); 803 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 804 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 805#endif // AMD64 806 st->cr(); 807 st->cr(); 808 809 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 810 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 811 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 812 st->cr(); 813 814 // Note: it may be unsafe to inspect memory near pc. For example, pc may 815 // point to garbage if entry point in an nmethod is corrupted. Leave 816 // this at the end, and hope for the best. 817 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 818 address pc = epc.pc(); 819 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 820 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 821} 822 823void os::print_register_info(outputStream *st, void *context) { 824 if (context == NULL) return; 825 826 ucontext_t *uc = (ucontext_t*)context; 827 828 st->print_cr("Register to memory mapping:"); 829 st->cr(); 830 831 // this is horrendously verbose but the layout of the registers in the 832 // context does not match how we defined our abstract Register set, so 833 // we can't just iterate through the gregs area 834 835 // this is only for the "general purpose" registers 836 837#ifdef AMD64 838 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]); 839 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]); 840 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]); 841 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]); 842 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]); 843 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]); 844 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]); 845 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]); 846 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]); 847 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]); 848 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]); 849 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]); 850 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]); 851 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]); 852 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]); 853 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]); 854#else 855 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]); 856 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]); 857 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]); 858 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]); 859 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]); 860 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]); 861 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]); 862 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]); 863#endif 864 865 st->cr(); 866} 867 868 869#ifdef AMD64 870void os::Solaris::init_thread_fpu_state(void) { 871 // Nothing to do 872} 873#else 874// From solaris_i486.s 875extern "C" void fixcw(); 876 877void os::Solaris::init_thread_fpu_state(void) { 878 // Set fpu to 53 bit precision. This happens too early to use a stub. 879 fixcw(); 880} 881 882// These routines are the initial value of atomic_xchg_entry(), 883// atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 884// until initialization is complete. 885// TODO - replace with .il implementation when compiler supports it. 886 887typedef jint xchg_func_t (jint, volatile jint*); 888typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 889typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 890typedef jint add_func_t (jint, volatile jint*); 891 892jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 893 // try to use the stub: 894 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 895 896 if (func != NULL) { 897 os::atomic_xchg_func = func; 898 return (*func)(exchange_value, dest); 899 } 900 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 901 902 jint old_value = *dest; 903 *dest = exchange_value; 904 return old_value; 905} 906 907jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 908 // try to use the stub: 909 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 910 911 if (func != NULL) { 912 os::atomic_cmpxchg_func = func; 913 return (*func)(exchange_value, dest, compare_value); 914 } 915 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 916 917 jint old_value = *dest; 918 if (old_value == compare_value) 919 *dest = exchange_value; 920 return old_value; 921} 922 923jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 924 // try to use the stub: 925 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 926 927 if (func != NULL) { 928 os::atomic_cmpxchg_long_func = func; 929 return (*func)(exchange_value, dest, compare_value); 930 } 931 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 932 933 jlong old_value = *dest; 934 if (old_value == compare_value) 935 *dest = exchange_value; 936 return old_value; 937} 938 939jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 940 // try to use the stub: 941 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 942 943 if (func != NULL) { 944 os::atomic_add_func = func; 945 return (*func)(add_value, dest); 946 } 947 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 948 949 return (*dest) += add_value; 950} 951 952xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 953cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 954cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 955add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 956 957extern "C" void _solaris_raw_setup_fpu(address ptr); 958void os::setup_fpu() { 959 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 960 _solaris_raw_setup_fpu(fpu_cntrl); 961} 962#endif // AMD64 963 964#ifndef PRODUCT 965void os::verify_stack_alignment() { 966#ifdef AMD64 967 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); 968#endif 969} 970#endif 971