1 /* 2 * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "asm/macroAssembler.hpp" 27 #include "classfile/classLoader.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/codeCache.hpp" 31 #include "code/icBuffer.hpp" 32 #include "code/vtableStubs.hpp" 33 #include "interpreter/interpreter.hpp" 34 #include "jvm_solaris.h" 35 #include "memory/allocation.inline.hpp" 36 #include "os_share_solaris.hpp" 37 #include "prims/jniFastGetField.hpp" 38 #include "prims/jvm.h" 39 #include "prims/jvm_misc.hpp" 40 #include "runtime/arguments.hpp" 41 #include "runtime/atomic.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/thread.inline.hpp" 52 #include "runtime/timer.hpp" 53 #include "utilities/events.hpp" 54 #include "utilities/vmError.hpp" 55 56 // put OS-includes here 57 # include <sys/types.h> 58 # include <sys/mman.h> 59 # include <pthread.h> 60 # include <signal.h> 61 # include <setjmp.h> 62 # include <errno.h> 63 # include <dlfcn.h> 64 # include <stdio.h> 65 # include <unistd.h> 66 # include <sys/resource.h> 67 # include <thread.h> 68 # include <sys/stat.h> 69 # include <sys/time.h> 70 # include <sys/filio.h> 71 # include <sys/utsname.h> 72 # include <sys/systeminfo.h> 73 # include <sys/socket.h> 74 # include <sys/trap.h> 75 # include <sys/lwp.h> 76 # include <poll.h> 77 # include <sys/lwp.h> 78 # include <procfs.h> // see comment in <sys/procfs.h> 79 80 #ifndef AMD64 81 // QQQ seems useless at this point 82 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later 83 #endif // AMD64 84 # include <sys/procfs.h> // see comment in <sys/procfs.h> 85 86 87 #define MAX_PATH (2 * K) 88 89 // Minimum stack size for the VM. It's easier to document a constant value 90 // but it's different for x86 and sparc because the page sizes are different. 91 #ifdef AMD64 92 size_t os::Solaris::min_stack_allowed = 224*K; 93 #define REG_SP REG_RSP 94 #define REG_PC REG_RIP 95 #define REG_FP REG_RBP 96 #else 97 size_t os::Solaris::min_stack_allowed = 64*K; 98 #define REG_SP UESP 99 #define REG_PC EIP 100 #define REG_FP EBP 101 // 4900493 counter to prevent runaway LDTR refresh attempt 102 103 static volatile int ldtr_refresh = 0; 104 // the libthread instruction that faults because of the stale LDTR 105 106 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs 107 }; 108 #endif // AMD64 109 110 char* os::non_memory_address_word() { 111 // Must never look like an address returned by reserve_memory, 112 // even in its subfields (as defined by the CPU immediate fields, 113 // if the CPU splits constants across multiple instructions). 114 return (char*) -1; 115 } 116 117 // 118 // Validate a ucontext retrieved from walking a uc_link of a ucontext. 119 // There are issues with libthread giving out uc_links for different threads 120 // on the same uc_link chain and bad or circular links. 121 // 122 bool os::Solaris::valid_ucontext(Thread* thread, const ucontext_t* valid, const ucontext_t* suspect) { 123 if (valid >= suspect || 124 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags || 125 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp || 126 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) { 127 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");) 128 return false; 129 } 130 131 if (thread->is_Java_thread()) { 132 if (!valid_stack_address(thread, (address)suspect)) { 133 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");) 134 return false; 135 } 136 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) { 137 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");) 138 return false; 139 } 140 } 141 return true; 142 } 143 144 // We will only follow one level of uc_link since there are libthread 145 // issues with ucontext linking and it is better to be safe and just 146 // let caller retry later. 147 const ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread, 148 const ucontext_t *uc) { 149 150 const ucontext_t *retuc = NULL; 151 152 if (uc != NULL) { 153 if (uc->uc_link == NULL) { 154 // cannot validate without uc_link so accept current ucontext 155 retuc = uc; 156 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 157 // first ucontext is valid so try the next one 158 uc = uc->uc_link; 159 if (uc->uc_link == NULL) { 160 // cannot validate without uc_link so accept current ucontext 161 retuc = uc; 162 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 163 // the ucontext one level down is also valid so return it 164 retuc = uc; 165 } 166 } 167 } 168 return retuc; 169 } 170 171 // Assumes ucontext is valid 172 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(const ucontext_t *uc) { 173 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]); 174 } 175 176 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) { 177 uc->uc_mcontext.gregs [REG_PC] = (greg_t) pc; 178 } 179 180 // Assumes ucontext is valid 181 intptr_t* os::Solaris::ucontext_get_sp(const ucontext_t *uc) { 182 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP]; 183 } 184 185 // Assumes ucontext is valid 186 intptr_t* os::Solaris::ucontext_get_fp(const ucontext_t *uc) { 187 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP]; 188 } 189 190 address os::Solaris::ucontext_get_pc(const ucontext_t *uc) { 191 return (address) uc->uc_mcontext.gregs[REG_PC]; 192 } 193 194 // For Forte Analyzer AsyncGetCallTrace profiling support - thread 195 // is currently interrupted by SIGPROF. 196 // 197 // The difference between this and os::fetch_frame_from_context() is that 198 // here we try to skip nested signal frames. 199 // This method is also used for stack overflow signal handling. 200 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread, 201 const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 202 203 assert(thread != NULL, "just checking"); 204 assert(ret_sp != NULL, "just checking"); 205 assert(ret_fp != NULL, "just checking"); 206 207 const ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc); 208 return os::fetch_frame_from_context(luc, ret_sp, ret_fp); 209 } 210 211 ExtendedPC os::fetch_frame_from_context(const void* ucVoid, 212 intptr_t** ret_sp, intptr_t** ret_fp) { 213 214 ExtendedPC epc; 215 const ucontext_t *uc = (const ucontext_t*)ucVoid; 216 217 if (uc != NULL) { 218 epc = os::Solaris::ucontext_get_ExtendedPC(uc); 219 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc); 220 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc); 221 } else { 222 // construct empty ExtendedPC for return value checking 223 epc = ExtendedPC(NULL); 224 if (ret_sp) *ret_sp = (intptr_t *)NULL; 225 if (ret_fp) *ret_fp = (intptr_t *)NULL; 226 } 227 228 return epc; 229 } 230 231 frame os::fetch_frame_from_context(const void* ucVoid) { 232 intptr_t* sp; 233 intptr_t* fp; 234 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 235 return frame(sp, fp, epc.pc()); 236 } 237 238 frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) { 239 intptr_t* sp; 240 intptr_t* fp; 241 ExtendedPC epc = os::Solaris::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp); 242 return frame(sp, fp, epc.pc()); 243 } 244 245 bool os::Solaris::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) { 246 address pc = (address) os::Solaris::ucontext_get_pc(uc); 247 if (Interpreter::contains(pc)) { 248 // interpreter performs stack banging after the fixed frame header has 249 // been generated while the compilers perform it before. To maintain 250 // semantic consistency between interpreted and compiled frames, the 251 // method returns the Java sender of the current frame. 252 *fr = os::fetch_frame_from_ucontext(thread, uc); 253 if (!fr->is_first_java_frame()) { 254 assert(fr->safe_for_sender(thread), "Safety check"); 255 *fr = fr->java_sender(); 256 } 257 } else { 258 // more complex code with compiled code 259 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above"); 260 CodeBlob* cb = CodeCache::find_blob(pc); 261 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) { 262 // Not sure where the pc points to, fallback to default 263 // stack overflow handling 264 return false; 265 } else { 266 // in compiled code, the stack banging is performed just after the return pc 267 // has been pushed on the stack 268 intptr_t* fp = os::Solaris::ucontext_get_fp(uc); 269 intptr_t* sp = os::Solaris::ucontext_get_sp(uc); 270 *fr = frame(sp + 1, fp, (address)*sp); 271 if (!fr->is_java_frame()) { 272 assert(fr->safe_for_sender(thread), "Safety check"); 273 *fr = fr->java_sender(); 274 } 275 } 276 } 277 assert(fr->is_java_frame(), "Safety check"); 278 return true; 279 } 280 281 frame os::get_sender_for_C_frame(frame* fr) { 282 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 283 } 284 285 extern "C" intptr_t *_get_current_sp(); // in .il file 286 287 address os::current_stack_pointer() { 288 return (address)_get_current_sp(); 289 } 290 291 extern "C" intptr_t *_get_current_fp(); // in .il file 292 293 frame os::current_frame() { 294 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp 295 // fp is for os::current_frame. We want the fp for our caller. 296 frame myframe((intptr_t*)os::current_stack_pointer(), 297 (intptr_t*)fp, 298 CAST_FROM_FN_PTR(address, os::current_frame)); 299 frame caller_frame = os::get_sender_for_C_frame(&myframe); 300 301 if (os::is_first_C_frame(&caller_frame)) { 302 // stack is not walkable 303 frame ret; // This will be a null useless frame 304 return ret; 305 } else { 306 // return frame for our caller's caller 307 return os::get_sender_for_C_frame(&caller_frame); 308 } 309 } 310 311 #ifndef AMD64 312 313 // Detecting SSE support by OS 314 // From solaris_i486.s 315 extern "C" bool sse_check(); 316 extern "C" bool sse_unavailable(); 317 318 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 319 static int sse_status = SSE_UNKNOWN; 320 321 322 static void check_for_sse_support() { 323 if (!VM_Version::supports_sse()) { 324 sse_status = SSE_NOT_SUPPORTED; 325 return; 326 } 327 // looking for _sse_hw in libc.so, if it does not exist or 328 // the value (int) is 0, OS has no support for SSE 329 int *sse_hwp; 330 void *h; 331 332 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 333 //open failed, presume no support for SSE 334 sse_status = SSE_NOT_SUPPORTED; 335 return; 336 } 337 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 338 sse_status = SSE_NOT_SUPPORTED; 339 } else if (*sse_hwp == 0) { 340 sse_status = SSE_NOT_SUPPORTED; 341 } 342 dlclose(h); 343 344 if (sse_status == SSE_UNKNOWN) { 345 bool (*try_sse)() = (bool (*)())sse_check; 346 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 347 } 348 349 } 350 351 #endif // AMD64 352 353 bool os::supports_sse() { 354 #ifdef AMD64 355 return true; 356 #else 357 if (sse_status == SSE_UNKNOWN) 358 check_for_sse_support(); 359 return sse_status == SSE_SUPPORTED; 360 #endif // AMD64 361 } 362 363 bool os::is_allocatable(size_t bytes) { 364 #ifdef AMD64 365 return true; 366 #else 367 368 if (bytes < 2 * G) { 369 return true; 370 } 371 372 char* addr = reserve_memory(bytes, NULL); 373 374 if (addr != NULL) { 375 release_memory(addr, bytes); 376 } 377 378 return addr != NULL; 379 #endif // AMD64 380 381 } 382 383 extern "C" JNIEXPORT int 384 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, 385 int abort_if_unrecognized) { 386 ucontext_t* uc = (ucontext_t*) ucVoid; 387 388 #ifndef AMD64 389 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 390 // the SSE instruction faulted. supports_sse() need return false. 391 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 392 return true; 393 } 394 #endif // !AMD64 395 396 Thread* t = Thread::current_or_null_safe(); 397 398 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away 399 // (no destructors can be run) 400 os::WatcherThreadCrashProtection::check_crash_protection(sig, t); 401 402 SignalHandlerMark shm(t); 403 404 if(sig == SIGPIPE || sig == SIGXFSZ) { 405 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 406 return true; 407 } else { 408 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219 409 return true; 410 } 411 } 412 413 JavaThread* thread = NULL; 414 VMThread* vmthread = NULL; 415 416 if (os::Solaris::signal_handlers_are_installed) { 417 if (t != NULL ){ 418 if(t->is_Java_thread()) { 419 thread = (JavaThread*)t; 420 } 421 else if(t->is_VM_thread()){ 422 vmthread = (VMThread *)t; 423 } 424 } 425 } 426 427 if (sig == os::Solaris::SIGasync()) { 428 if(thread || vmthread){ 429 OSThread::SR_handler(t, uc); 430 return true; 431 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 432 return true; 433 } else { 434 // If os::Solaris::SIGasync not chained, and this is a non-vm and 435 // non-java thread 436 return true; 437 } 438 } 439 440 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 441 // can't decode this kind of signal 442 info = NULL; 443 } else { 444 assert(sig == info->si_signo, "bad siginfo"); 445 } 446 447 // decide if this trap can be handled by a stub 448 address stub = NULL; 449 450 address pc = NULL; 451 452 //%note os_trap_1 453 if (info != NULL && uc != NULL && thread != NULL) { 454 // factor me: getPCfromContext 455 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 456 457 if (StubRoutines::is_safefetch_fault(pc)) { 458 os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc)); 459 return true; 460 } 461 462 // Handle ALL stack overflow variations here 463 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 464 address addr = (address) info->si_addr; 465 if (thread->in_stack_yellow_reserved_zone(addr)) { 466 if (thread->thread_state() == _thread_in_Java) { 467 if (thread->in_stack_reserved_zone(addr)) { 468 frame fr; 469 if (os::Solaris::get_frame_at_stack_banging_point(thread, uc, &fr)) { 470 assert(fr.is_java_frame(), "Must be Java frame"); 471 frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr); 472 if (activation.sp() != NULL) { 473 thread->disable_stack_reserved_zone(); 474 if (activation.is_interpreted_frame()) { 475 thread->set_reserved_stack_activation((address)( 476 activation.fp() + frame::interpreter_frame_initial_sp_offset)); 477 } else { 478 thread->set_reserved_stack_activation((address)activation.unextended_sp()); 479 } 480 return true; 481 } 482 } 483 } 484 // Throw a stack overflow exception. Guard pages will be reenabled 485 // while unwinding the stack. 486 thread->disable_stack_yellow_reserved_zone(); 487 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 488 } else { 489 // Thread was in the vm or native code. Return and try to finish. 490 thread->disable_stack_yellow_reserved_zone(); 491 return true; 492 } 493 } else if (thread->in_stack_red_zone(addr)) { 494 // Fatal red zone violation. Disable the guard pages and fall through 495 // to handle_unexpected_exception way down below. 496 thread->disable_stack_red_zone(); 497 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 498 } 499 } 500 501 if ((sig == SIGSEGV) && VM_Version::is_cpuinfo_segv_addr(pc)) { 502 // Verify that OS save/restore AVX registers. 503 stub = VM_Version::cpuinfo_cont_addr(); 504 } 505 506 if (thread->thread_state() == _thread_in_vm) { 507 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 508 address next_pc = Assembler::locate_next_instruction(pc); 509 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 510 } 511 } 512 513 if (thread->thread_state() == _thread_in_Java) { 514 // Support Safepoint Polling 515 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 516 stub = SharedRuntime::get_poll_stub(pc); 517 } 518 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 519 // BugId 4454115: A read from a MappedByteBuffer can fault 520 // here if the underlying file has been truncated. 521 // Do not crash the VM in such a case. 522 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 523 if (cb != NULL) { 524 CompiledMethod* nm = cb->as_compiled_method_or_null(); 525 if (nm != NULL && nm->has_unsafe_access()) { 526 address next_pc = Assembler::locate_next_instruction(pc); 527 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 528 } 529 } 530 } 531 else 532 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 533 // integer divide by zero 534 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 535 } 536 #ifndef AMD64 537 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 538 // floating-point divide by zero 539 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 540 } 541 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 542 // The encoding of D2I in i486.ad can cause an exception prior 543 // to the fist instruction if there was an invalid operation 544 // pending. We want to dismiss that exception. From the win_32 545 // side it also seems that if it really was the fist causing 546 // the exception that we do the d2i by hand with different 547 // rounding. Seems kind of weird. QQQ TODO 548 // Note that we take the exception at the NEXT floating point instruction. 549 if (pc[0] == 0xDB) { 550 assert(pc[0] == 0xDB, "not a FIST opcode"); 551 assert(pc[1] == 0x14, "not a FIST opcode"); 552 assert(pc[2] == 0x24, "not a FIST opcode"); 553 return true; 554 } else { 555 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 556 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 557 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 558 } 559 } 560 else if (sig == SIGFPE ) { 561 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 562 } 563 #endif // !AMD64 564 565 // QQQ It doesn't seem that we need to do this on x86 because we should be able 566 // to return properly from the handler without this extra stuff on the back side. 567 568 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 569 // Determination of interpreter/vtable stub/compiled code null exception 570 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 571 } 572 } 573 574 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 575 // and the heap gets shrunk before the field access. 576 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 577 address addr = JNI_FastGetField::find_slowcase_pc(pc); 578 if (addr != (address)-1) { 579 stub = addr; 580 } 581 } 582 583 // Check to see if we caught the safepoint code in the 584 // process of write protecting the memory serialization page. 585 // It write enables the page immediately after protecting it 586 // so we can just return to retry the write. 587 if ((sig == SIGSEGV) && 588 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 589 // Block current thread until the memory serialize page permission restored. 590 os::block_on_serialize_page_trap(); 591 return true; 592 } 593 } 594 595 // Execution protection violation 596 // 597 // Preventative code for future versions of Solaris which may 598 // enable execution protection when running the 32-bit VM on AMD64. 599 // 600 // This should be kept as the last step in the triage. We don't 601 // have a dedicated trap number for a no-execute fault, so be 602 // conservative and allow other handlers the first shot. 603 // 604 // Note: We don't test that info->si_code == SEGV_ACCERR here. 605 // this si_code is so generic that it is almost meaningless; and 606 // the si_code for this condition may change in the future. 607 // Furthermore, a false-positive should be harmless. 608 if (UnguardOnExecutionViolation > 0 && 609 (sig == SIGSEGV || sig == SIGBUS) && 610 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 611 int page_size = os::vm_page_size(); 612 address addr = (address) info->si_addr; 613 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 614 // Make sure the pc and the faulting address are sane. 615 // 616 // If an instruction spans a page boundary, and the page containing 617 // the beginning of the instruction is executable but the following 618 // page is not, the pc and the faulting address might be slightly 619 // different - we still want to unguard the 2nd page in this case. 620 // 621 // 15 bytes seems to be a (very) safe value for max instruction size. 622 bool pc_is_near_addr = 623 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 624 bool instr_spans_page_boundary = 625 (align_size_down((intptr_t) pc ^ (intptr_t) addr, 626 (intptr_t) page_size) > 0); 627 628 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 629 static volatile address last_addr = 630 (address) os::non_memory_address_word(); 631 632 // In conservative mode, don't unguard unless the address is in the VM 633 if (addr != last_addr && 634 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 635 636 // Make memory rwx and retry 637 address page_start = 638 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); 639 bool res = os::protect_memory((char*) page_start, page_size, 640 os::MEM_PROT_RWX); 641 642 log_debug(os)("Execution protection violation " 643 "at " INTPTR_FORMAT 644 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", p2i(addr), 645 p2i(page_start), (res ? "success" : "failed"), errno); 646 stub = pc; 647 648 // Set last_addr so if we fault again at the same address, we don't end 649 // up in an endless loop. 650 // 651 // There are two potential complications here. Two threads trapping at 652 // the same address at the same time could cause one of the threads to 653 // think it already unguarded, and abort the VM. Likely very rare. 654 // 655 // The other race involves two threads alternately trapping at 656 // different addresses and failing to unguard the page, resulting in 657 // an endless loop. This condition is probably even more unlikely than 658 // the first. 659 // 660 // Although both cases could be avoided by using locks or thread local 661 // last_addr, these solutions are unnecessary complication: this 662 // handler is a best-effort safety net, not a complete solution. It is 663 // disabled by default and should only be used as a workaround in case 664 // we missed any no-execute-unsafe VM code. 665 666 last_addr = addr; 667 } 668 } 669 } 670 671 if (stub != NULL) { 672 // save all thread context in case we need to restore it 673 674 if (thread != NULL) thread->set_saved_exception_pc(pc); 675 // 12/02/99: On Sparc it appears that the full context is also saved 676 // but as yet, no one looks at or restores that saved context 677 os::Solaris::ucontext_set_pc(uc, stub); 678 return true; 679 } 680 681 // signal-chaining 682 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 683 return true; 684 } 685 686 #ifndef AMD64 687 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 688 // Handle an undefined selector caused by an attempt to assign 689 // fs in libthread getipriptr(). With the current libthread design every 512 690 // thread creations the LDT for a private thread data structure is extended 691 // and thre is a hazard that and another thread attempting a thread creation 692 // will use a stale LDTR that doesn't reflect the structure's growth, 693 // causing a GP fault. 694 // Enforce the probable limit of passes through here to guard against an 695 // infinite loop if some other move to fs caused the GP fault. Note that 696 // this loop counter is ultimately a heuristic as it is possible for 697 // more than one thread to generate this fault at a time in an MP system. 698 // In the case of the loop count being exceeded or if the poll fails 699 // just fall through to a fatal error. 700 // If there is some other source of T_GPFLT traps and the text at EIP is 701 // unreadable this code will loop infinitely until the stack is exausted. 702 // The key to diagnosis in this case is to look for the bottom signal handler 703 // frame. 704 705 if(! IgnoreLibthreadGPFault) { 706 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 707 const unsigned char *p = 708 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 709 710 // Expected instruction? 711 712 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 713 714 Atomic::inc(&ldtr_refresh); 715 716 // Infinite loop? 717 718 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 719 720 // No, force scheduling to get a fresh view of the LDTR 721 722 if(poll(NULL, 0, 10) == 0) { 723 724 // Retry the move 725 726 return false; 727 } 728 } 729 } 730 } 731 } 732 #endif // !AMD64 733 734 if (!abort_if_unrecognized) { 735 // caller wants another chance, so give it to him 736 return false; 737 } 738 739 if (!os::Solaris::libjsig_is_loaded) { 740 struct sigaction oldAct; 741 sigaction(sig, (struct sigaction *)0, &oldAct); 742 if (oldAct.sa_sigaction != signalHandler) { 743 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 744 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 745 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand); 746 } 747 } 748 749 if (pc == NULL && uc != NULL) { 750 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 751 } 752 753 // unmask current signal 754 sigset_t newset; 755 sigemptyset(&newset); 756 sigaddset(&newset, sig); 757 sigprocmask(SIG_UNBLOCK, &newset, NULL); 758 759 // Determine which sort of error to throw. Out of swap may signal 760 // on the thread stack, which could get a mapping error when touched. 761 address addr = (address) info->si_addr; 762 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) { 763 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack."); 764 } 765 766 VMError::report_and_die(t, sig, pc, info, ucVoid); 767 768 ShouldNotReachHere(); 769 return false; 770 } 771 772 void os::print_context(outputStream *st, const void *context) { 773 if (context == NULL) return; 774 775 const ucontext_t *uc = (const ucontext_t*)context; 776 st->print_cr("Registers:"); 777 #ifdef AMD64 778 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 779 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 780 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 781 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 782 st->cr(); 783 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 784 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 785 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 786 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 787 st->cr(); 788 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 789 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 790 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 791 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 792 st->cr(); 793 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 794 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 795 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 796 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 797 st->cr(); 798 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 799 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 800 #else 801 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 802 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 803 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 804 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 805 st->cr(); 806 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 807 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 808 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 809 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 810 st->cr(); 811 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 812 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 813 #endif // AMD64 814 st->cr(); 815 st->cr(); 816 817 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 818 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 819 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 820 st->cr(); 821 822 // Note: it may be unsafe to inspect memory near pc. For example, pc may 823 // point to garbage if entry point in an nmethod is corrupted. Leave 824 // this at the end, and hope for the best. 825 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 826 address pc = epc.pc(); 827 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 828 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 829 } 830 831 void os::print_register_info(outputStream *st, const void *context) { 832 if (context == NULL) return; 833 834 const ucontext_t *uc = (const ucontext_t*)context; 835 836 st->print_cr("Register to memory mapping:"); 837 st->cr(); 838 839 // this is horrendously verbose but the layout of the registers in the 840 // context does not match how we defined our abstract Register set, so 841 // we can't just iterate through the gregs area 842 843 // this is only for the "general purpose" registers 844 845 #ifdef AMD64 846 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]); 847 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]); 848 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]); 849 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]); 850 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]); 851 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]); 852 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]); 853 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]); 854 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]); 855 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]); 856 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]); 857 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]); 858 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]); 859 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]); 860 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]); 861 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]); 862 #else 863 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]); 864 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]); 865 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]); 866 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]); 867 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]); 868 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]); 869 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]); 870 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]); 871 #endif 872 873 st->cr(); 874 } 875 876 877 #ifdef AMD64 878 void os::Solaris::init_thread_fpu_state(void) { 879 // Nothing to do 880 } 881 #else 882 // From solaris_i486.s 883 extern "C" void fixcw(); 884 885 void os::Solaris::init_thread_fpu_state(void) { 886 // Set fpu to 53 bit precision. This happens too early to use a stub. 887 fixcw(); 888 } 889 890 // These routines are the initial value of atomic_xchg_entry(), 891 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 892 // until initialization is complete. 893 // TODO - replace with .il implementation when compiler supports it. 894 895 typedef jint xchg_func_t (jint, volatile jint*); 896 typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 897 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 898 typedef jint add_func_t (jint, volatile jint*); 899 900 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 901 // try to use the stub: 902 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 903 904 if (func != NULL) { 905 os::atomic_xchg_func = func; 906 return (*func)(exchange_value, dest); 907 } 908 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 909 910 jint old_value = *dest; 911 *dest = exchange_value; 912 return old_value; 913 } 914 915 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 916 // try to use the stub: 917 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 918 919 if (func != NULL) { 920 os::atomic_cmpxchg_func = func; 921 return (*func)(exchange_value, dest, compare_value); 922 } 923 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 924 925 jint old_value = *dest; 926 if (old_value == compare_value) 927 *dest = exchange_value; 928 return old_value; 929 } 930 931 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 932 // try to use the stub: 933 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 934 935 if (func != NULL) { 936 os::atomic_cmpxchg_long_func = func; 937 return (*func)(exchange_value, dest, compare_value); 938 } 939 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 940 941 jlong old_value = *dest; 942 if (old_value == compare_value) 943 *dest = exchange_value; 944 return old_value; 945 } 946 947 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 948 // try to use the stub: 949 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 950 951 if (func != NULL) { 952 os::atomic_add_func = func; 953 return (*func)(add_value, dest); 954 } 955 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 956 957 return (*dest) += add_value; 958 } 959 960 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 961 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 962 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 963 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 964 965 extern "C" void _solaris_raw_setup_fpu(address ptr); 966 void os::setup_fpu() { 967 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 968 _solaris_raw_setup_fpu(fpu_cntrl); 969 } 970 #endif // AMD64 971 972 #ifndef PRODUCT 973 void os::verify_stack_alignment() { 974 #ifdef AMD64 975 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); 976 #endif 977 } 978 #endif 979 980 int os::extra_bang_size_in_bytes() { 981 // JDK-8050147 requires the full cache line bang for x86. 982 return VM_Version::L1_line_size(); 983 }