1 /* 2 * Copyright (c) 1999, 2017, 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 "jvm.h" 27 #include "asm/macroAssembler.hpp" 28 #include "classfile/classLoader.hpp" 29 #include "classfile/systemDictionary.hpp" 30 #include "classfile/vmSymbols.hpp" 31 #include "code/codeCache.hpp" 32 #include "code/icBuffer.hpp" 33 #include "code/vtableStubs.hpp" 34 #include "interpreter/interpreter.hpp" 35 #include "memory/allocation.inline.hpp" 36 #include "os_share_solaris.hpp" 37 #include "prims/jniFastGetField.hpp" 38 #include "prims/jvm_misc.hpp" 39 #include "runtime/arguments.hpp" 40 #include "runtime/atomic.hpp" 41 #include "runtime/extendedPC.hpp" 42 #include "runtime/frame.inline.hpp" 43 #include "runtime/interfaceSupport.hpp" 44 #include "runtime/java.hpp" 45 #include "runtime/javaCalls.hpp" 46 #include "runtime/mutexLocker.hpp" 47 #include "runtime/osThread.hpp" 48 #include "runtime/sharedRuntime.hpp" 49 #include "runtime/stubRoutines.hpp" 50 #include "runtime/thread.inline.hpp" 51 #include "runtime/timer.hpp" 52 #include "utilities/align.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 usable stack sizes required to get to user code. Space for 90 // HotSpot guard pages is added later. 91 #ifdef _LP64 92 // The adlc generated method 'State::MachNodeGenerator(int)' used by the C2 compiler 93 // threads requires a large stack with the Solaris Studio C++ compiler version 5.13 94 // and product VM builds (debug builds require significantly less stack space). 95 size_t os::Posix::_compiler_thread_min_stack_allowed = 325 * K; 96 size_t os::Posix::_java_thread_min_stack_allowed = 48 * K; 97 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 224 * K; 98 #else 99 size_t os::Posix::_compiler_thread_min_stack_allowed = 32 * K; 100 size_t os::Posix::_java_thread_min_stack_allowed = 32 * K; 101 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K; 102 #endif // _LP64 103 104 #ifdef AMD64 105 #define REG_SP REG_RSP 106 #define REG_PC REG_RIP 107 #define REG_FP REG_RBP 108 #else 109 #define REG_SP UESP 110 #define REG_PC EIP 111 #define REG_FP EBP 112 // 4900493 counter to prevent runaway LDTR refresh attempt 113 114 static volatile int ldtr_refresh = 0; 115 // the libthread instruction that faults because of the stale LDTR 116 117 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs 118 }; 119 #endif // AMD64 120 121 char* os::non_memory_address_word() { 122 // Must never look like an address returned by reserve_memory, 123 // even in its subfields (as defined by the CPU immediate fields, 124 // if the CPU splits constants across multiple instructions). 125 return (char*) -1; 126 } 127 128 // 129 // Validate a ucontext retrieved from walking a uc_link of a ucontext. 130 // There are issues with libthread giving out uc_links for different threads 131 // on the same uc_link chain and bad or circular links. 132 // 133 bool os::Solaris::valid_ucontext(Thread* thread, const ucontext_t* valid, const ucontext_t* suspect) { 134 if (valid >= suspect || 135 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags || 136 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp || 137 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) { 138 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");) 139 return false; 140 } 141 142 if (thread->is_Java_thread()) { 143 if (!valid_stack_address(thread, (address)suspect)) { 144 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");) 145 return false; 146 } 147 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) { 148 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");) 149 return false; 150 } 151 } 152 return true; 153 } 154 155 // We will only follow one level of uc_link since there are libthread 156 // issues with ucontext linking and it is better to be safe and just 157 // let caller retry later. 158 const ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread, 159 const ucontext_t *uc) { 160 161 const ucontext_t *retuc = NULL; 162 163 if (uc != NULL) { 164 if (uc->uc_link == NULL) { 165 // cannot validate without uc_link so accept current ucontext 166 retuc = uc; 167 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 168 // first ucontext is valid so try the next one 169 uc = uc->uc_link; 170 if (uc->uc_link == NULL) { 171 // cannot validate without uc_link so accept current ucontext 172 retuc = uc; 173 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 174 // the ucontext one level down is also valid so return it 175 retuc = uc; 176 } 177 } 178 } 179 return retuc; 180 } 181 182 // Assumes ucontext is valid 183 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(const ucontext_t *uc) { 184 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]); 185 } 186 187 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) { 188 uc->uc_mcontext.gregs [REG_PC] = (greg_t) pc; 189 } 190 191 // Assumes ucontext is valid 192 intptr_t* os::Solaris::ucontext_get_sp(const ucontext_t *uc) { 193 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP]; 194 } 195 196 // Assumes ucontext is valid 197 intptr_t* os::Solaris::ucontext_get_fp(const ucontext_t *uc) { 198 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP]; 199 } 200 201 address os::Solaris::ucontext_get_pc(const ucontext_t *uc) { 202 return (address) uc->uc_mcontext.gregs[REG_PC]; 203 } 204 205 // For Forte Analyzer AsyncGetCallTrace profiling support - thread 206 // is currently interrupted by SIGPROF. 207 // 208 // The difference between this and os::fetch_frame_from_context() is that 209 // here we try to skip nested signal frames. 210 // This method is also used for stack overflow signal handling. 211 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread, 212 const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 213 214 assert(thread != NULL, "just checking"); 215 assert(ret_sp != NULL, "just checking"); 216 assert(ret_fp != NULL, "just checking"); 217 218 const ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc); 219 return os::fetch_frame_from_context(luc, ret_sp, ret_fp); 220 } 221 222 ExtendedPC os::fetch_frame_from_context(const void* ucVoid, 223 intptr_t** ret_sp, intptr_t** ret_fp) { 224 225 ExtendedPC epc; 226 const ucontext_t *uc = (const ucontext_t*)ucVoid; 227 228 if (uc != NULL) { 229 epc = os::Solaris::ucontext_get_ExtendedPC(uc); 230 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc); 231 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc); 232 } else { 233 // construct empty ExtendedPC for return value checking 234 epc = ExtendedPC(NULL); 235 if (ret_sp) *ret_sp = (intptr_t *)NULL; 236 if (ret_fp) *ret_fp = (intptr_t *)NULL; 237 } 238 239 return epc; 240 } 241 242 frame os::fetch_frame_from_context(const void* ucVoid) { 243 intptr_t* sp; 244 intptr_t* fp; 245 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 246 return frame(sp, fp, epc.pc()); 247 } 248 249 frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) { 250 intptr_t* sp; 251 intptr_t* fp; 252 ExtendedPC epc = os::Solaris::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp); 253 return frame(sp, fp, epc.pc()); 254 } 255 256 bool os::Solaris::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) { 257 address pc = (address) os::Solaris::ucontext_get_pc(uc); 258 if (Interpreter::contains(pc)) { 259 // interpreter performs stack banging after the fixed frame header has 260 // been generated while the compilers perform it before. To maintain 261 // semantic consistency between interpreted and compiled frames, the 262 // method returns the Java sender of the current frame. 263 *fr = os::fetch_frame_from_ucontext(thread, uc); 264 if (!fr->is_first_java_frame()) { 265 // get_frame_at_stack_banging_point() is only called when we 266 // have well defined stacks so java_sender() calls do not need 267 // to assert safe_for_sender() first. 268 *fr = fr->java_sender(); 269 } 270 } else { 271 // more complex code with compiled code 272 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above"); 273 CodeBlob* cb = CodeCache::find_blob(pc); 274 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) { 275 // Not sure where the pc points to, fallback to default 276 // stack overflow handling 277 return false; 278 } else { 279 // in compiled code, the stack banging is performed just after the return pc 280 // has been pushed on the stack 281 intptr_t* fp = os::Solaris::ucontext_get_fp(uc); 282 intptr_t* sp = os::Solaris::ucontext_get_sp(uc); 283 *fr = frame(sp + 1, fp, (address)*sp); 284 if (!fr->is_java_frame()) { 285 // See java_sender() comment above. 286 *fr = fr->java_sender(); 287 } 288 } 289 } 290 assert(fr->is_java_frame(), "Safety check"); 291 return true; 292 } 293 294 frame os::get_sender_for_C_frame(frame* fr) { 295 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 296 } 297 298 extern "C" intptr_t *_get_current_sp(); // in .il file 299 300 address os::current_stack_pointer() { 301 return (address)_get_current_sp(); 302 } 303 304 extern "C" intptr_t *_get_current_fp(); // in .il file 305 306 frame os::current_frame() { 307 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp 308 // fp is for os::current_frame. We want the fp for our caller. 309 frame myframe((intptr_t*)os::current_stack_pointer(), 310 (intptr_t*)fp, 311 CAST_FROM_FN_PTR(address, os::current_frame)); 312 frame caller_frame = os::get_sender_for_C_frame(&myframe); 313 314 if (os::is_first_C_frame(&caller_frame)) { 315 // stack is not walkable 316 frame ret; // This will be a null useless frame 317 return ret; 318 } else { 319 // return frame for our caller's caller 320 return os::get_sender_for_C_frame(&caller_frame); 321 } 322 } 323 324 #ifndef AMD64 325 326 // Detecting SSE support by OS 327 // From solaris_i486.s 328 extern "C" bool sse_check(); 329 extern "C" bool sse_unavailable(); 330 331 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 332 static int sse_status = SSE_UNKNOWN; 333 334 335 static void check_for_sse_support() { 336 if (!VM_Version::supports_sse()) { 337 sse_status = SSE_NOT_SUPPORTED; 338 return; 339 } 340 // looking for _sse_hw in libc.so, if it does not exist or 341 // the value (int) is 0, OS has no support for SSE 342 int *sse_hwp; 343 void *h; 344 345 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 346 //open failed, presume no support for SSE 347 sse_status = SSE_NOT_SUPPORTED; 348 return; 349 } 350 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 351 sse_status = SSE_NOT_SUPPORTED; 352 } else if (*sse_hwp == 0) { 353 sse_status = SSE_NOT_SUPPORTED; 354 } 355 dlclose(h); 356 357 if (sse_status == SSE_UNKNOWN) { 358 bool (*try_sse)() = (bool (*)())sse_check; 359 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 360 } 361 362 } 363 364 #endif // AMD64 365 366 bool os::supports_sse() { 367 #ifdef AMD64 368 return true; 369 #else 370 if (sse_status == SSE_UNKNOWN) 371 check_for_sse_support(); 372 return sse_status == SSE_SUPPORTED; 373 #endif // AMD64 374 } 375 376 bool os::is_allocatable(size_t bytes) { 377 #ifdef AMD64 378 return true; 379 #else 380 381 if (bytes < 2 * G) { 382 return true; 383 } 384 385 char* addr = reserve_memory(bytes, NULL); 386 387 if (addr != NULL) { 388 release_memory(addr, bytes); 389 } 390 391 return addr != NULL; 392 #endif // AMD64 393 394 } 395 396 extern "C" JNIEXPORT int 397 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, 398 int abort_if_unrecognized) { 399 ucontext_t* uc = (ucontext_t*) ucVoid; 400 401 #ifndef AMD64 402 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 403 // the SSE instruction faulted. supports_sse() need return false. 404 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 405 return true; 406 } 407 #endif // !AMD64 408 409 Thread* t = Thread::current_or_null_safe(); 410 411 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away 412 // (no destructors can be run) 413 os::ThreadCrashProtection::check_crash_protection(sig, t); 414 415 SignalHandlerMark shm(t); 416 417 if(sig == SIGPIPE || sig == SIGXFSZ) { 418 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 419 return true; 420 } else { 421 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219 422 return true; 423 } 424 } 425 426 JavaThread* thread = NULL; 427 VMThread* vmthread = NULL; 428 429 if (os::Solaris::signal_handlers_are_installed) { 430 if (t != NULL ){ 431 if(t->is_Java_thread()) { 432 thread = (JavaThread*)t; 433 } 434 else if(t->is_VM_thread()){ 435 vmthread = (VMThread *)t; 436 } 437 } 438 } 439 440 if (sig == ASYNC_SIGNAL) { 441 if(thread || vmthread){ 442 OSThread::SR_handler(t, uc); 443 return true; 444 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 445 return true; 446 } else { 447 // If ASYNC_SIGNAL not chained, and this is a non-vm and 448 // non-java thread 449 return true; 450 } 451 } 452 453 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 454 // can't decode this kind of signal 455 info = NULL; 456 } else { 457 assert(sig == info->si_signo, "bad siginfo"); 458 } 459 460 // decide if this trap can be handled by a stub 461 address stub = NULL; 462 463 address pc = NULL; 464 465 //%note os_trap_1 466 if (info != NULL && uc != NULL && thread != NULL) { 467 // factor me: getPCfromContext 468 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 469 470 if (StubRoutines::is_safefetch_fault(pc)) { 471 os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc)); 472 return true; 473 } 474 475 // Handle ALL stack overflow variations here 476 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 477 address addr = (address) info->si_addr; 478 if (thread->in_stack_yellow_reserved_zone(addr)) { 479 if (thread->thread_state() == _thread_in_Java) { 480 if (thread->in_stack_reserved_zone(addr)) { 481 frame fr; 482 if (os::Solaris::get_frame_at_stack_banging_point(thread, uc, &fr)) { 483 assert(fr.is_java_frame(), "Must be Java frame"); 484 frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr); 485 if (activation.sp() != NULL) { 486 thread->disable_stack_reserved_zone(); 487 if (activation.is_interpreted_frame()) { 488 thread->set_reserved_stack_activation((address)( 489 activation.fp() + frame::interpreter_frame_initial_sp_offset)); 490 } else { 491 thread->set_reserved_stack_activation((address)activation.unextended_sp()); 492 } 493 return true; 494 } 495 } 496 } 497 // Throw a stack overflow exception. Guard pages will be reenabled 498 // while unwinding the stack. 499 thread->disable_stack_yellow_reserved_zone(); 500 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 501 } else { 502 // Thread was in the vm or native code. Return and try to finish. 503 thread->disable_stack_yellow_reserved_zone(); 504 return true; 505 } 506 } else if (thread->in_stack_red_zone(addr)) { 507 // Fatal red zone violation. Disable the guard pages and fall through 508 // to handle_unexpected_exception way down below. 509 thread->disable_stack_red_zone(); 510 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 511 } 512 } 513 514 if ((sig == SIGSEGV) && VM_Version::is_cpuinfo_segv_addr(pc)) { 515 // Verify that OS save/restore AVX registers. 516 stub = VM_Version::cpuinfo_cont_addr(); 517 } 518 519 if (thread->thread_state() == _thread_in_vm) { 520 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 521 address next_pc = Assembler::locate_next_instruction(pc); 522 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 523 } 524 } 525 526 if (thread->thread_state() == _thread_in_Java) { 527 // Support Safepoint Polling 528 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 529 stub = SharedRuntime::get_poll_stub(pc); 530 } 531 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 532 // BugId 4454115: A read from a MappedByteBuffer can fault 533 // here if the underlying file has been truncated. 534 // Do not crash the VM in such a case. 535 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 536 if (cb != NULL) { 537 CompiledMethod* nm = cb->as_compiled_method_or_null(); 538 if (nm != NULL && nm->has_unsafe_access()) { 539 address next_pc = Assembler::locate_next_instruction(pc); 540 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 541 } 542 } 543 } 544 else 545 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 546 // integer divide by zero 547 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 548 } 549 #ifndef AMD64 550 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 551 // floating-point divide by zero 552 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 553 } 554 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 555 // The encoding of D2I in i486.ad can cause an exception prior 556 // to the fist instruction if there was an invalid operation 557 // pending. We want to dismiss that exception. From the win_32 558 // side it also seems that if it really was the fist causing 559 // the exception that we do the d2i by hand with different 560 // rounding. Seems kind of weird. QQQ TODO 561 // Note that we take the exception at the NEXT floating point instruction. 562 if (pc[0] == 0xDB) { 563 assert(pc[0] == 0xDB, "not a FIST opcode"); 564 assert(pc[1] == 0x14, "not a FIST opcode"); 565 assert(pc[2] == 0x24, "not a FIST opcode"); 566 return true; 567 } else { 568 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 569 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 570 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 571 } 572 } 573 else if (sig == SIGFPE ) { 574 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 575 } 576 #endif // !AMD64 577 578 // QQQ It doesn't seem that we need to do this on x86 because we should be able 579 // to return properly from the handler without this extra stuff on the back side. 580 581 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 582 // Determination of interpreter/vtable stub/compiled code null exception 583 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 584 } 585 } 586 587 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 588 // and the heap gets shrunk before the field access. 589 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 590 address addr = JNI_FastGetField::find_slowcase_pc(pc); 591 if (addr != (address)-1) { 592 stub = addr; 593 } 594 } 595 596 // Check to see if we caught the safepoint code in the 597 // process of write protecting the memory serialization page. 598 // It write enables the page immediately after protecting it 599 // so we can just return to retry the write. 600 if ((sig == SIGSEGV) && 601 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 602 // Block current thread until the memory serialize page permission restored. 603 os::block_on_serialize_page_trap(); 604 return true; 605 } 606 } 607 608 // Execution protection violation 609 // 610 // Preventative code for future versions of Solaris which may 611 // enable execution protection when running the 32-bit VM on AMD64. 612 // 613 // This should be kept as the last step in the triage. We don't 614 // have a dedicated trap number for a no-execute fault, so be 615 // conservative and allow other handlers the first shot. 616 // 617 // Note: We don't test that info->si_code == SEGV_ACCERR here. 618 // this si_code is so generic that it is almost meaningless; and 619 // the si_code for this condition may change in the future. 620 // Furthermore, a false-positive should be harmless. 621 if (UnguardOnExecutionViolation > 0 && 622 (sig == SIGSEGV || sig == SIGBUS) && 623 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 624 int page_size = os::vm_page_size(); 625 address addr = (address) info->si_addr; 626 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 627 // Make sure the pc and the faulting address are sane. 628 // 629 // If an instruction spans a page boundary, and the page containing 630 // the beginning of the instruction is executable but the following 631 // page is not, the pc and the faulting address might be slightly 632 // different - we still want to unguard the 2nd page in this case. 633 // 634 // 15 bytes seems to be a (very) safe value for max instruction size. 635 bool pc_is_near_addr = 636 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 637 bool instr_spans_page_boundary = 638 (align_down((intptr_t) pc ^ (intptr_t) addr, 639 (intptr_t) page_size) > 0); 640 641 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 642 static volatile address last_addr = 643 (address) os::non_memory_address_word(); 644 645 // In conservative mode, don't unguard unless the address is in the VM 646 if (addr != last_addr && 647 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 648 649 // Make memory rwx and retry 650 address page_start = align_down(addr, page_size); 651 bool res = os::protect_memory((char*) page_start, page_size, 652 os::MEM_PROT_RWX); 653 654 log_debug(os)("Execution protection violation " 655 "at " INTPTR_FORMAT 656 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", p2i(addr), 657 p2i(page_start), (res ? "success" : "failed"), errno); 658 stub = pc; 659 660 // Set last_addr so if we fault again at the same address, we don't end 661 // up in an endless loop. 662 // 663 // There are two potential complications here. Two threads trapping at 664 // the same address at the same time could cause one of the threads to 665 // think it already unguarded, and abort the VM. Likely very rare. 666 // 667 // The other race involves two threads alternately trapping at 668 // different addresses and failing to unguard the page, resulting in 669 // an endless loop. This condition is probably even more unlikely than 670 // the first. 671 // 672 // Although both cases could be avoided by using locks or thread local 673 // last_addr, these solutions are unnecessary complication: this 674 // handler is a best-effort safety net, not a complete solution. It is 675 // disabled by default and should only be used as a workaround in case 676 // we missed any no-execute-unsafe VM code. 677 678 last_addr = addr; 679 } 680 } 681 } 682 683 if (stub != NULL) { 684 // save all thread context in case we need to restore it 685 686 if (thread != NULL) thread->set_saved_exception_pc(pc); 687 // 12/02/99: On Sparc it appears that the full context is also saved 688 // but as yet, no one looks at or restores that saved context 689 os::Solaris::ucontext_set_pc(uc, stub); 690 return true; 691 } 692 693 // signal-chaining 694 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 695 return true; 696 } 697 698 #ifndef AMD64 699 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 700 // Handle an undefined selector caused by an attempt to assign 701 // fs in libthread getipriptr(). With the current libthread design every 512 702 // thread creations the LDT for a private thread data structure is extended 703 // and thre is a hazard that and another thread attempting a thread creation 704 // will use a stale LDTR that doesn't reflect the structure's growth, 705 // causing a GP fault. 706 // Enforce the probable limit of passes through here to guard against an 707 // infinite loop if some other move to fs caused the GP fault. Note that 708 // this loop counter is ultimately a heuristic as it is possible for 709 // more than one thread to generate this fault at a time in an MP system. 710 // In the case of the loop count being exceeded or if the poll fails 711 // just fall through to a fatal error. 712 // If there is some other source of T_GPFLT traps and the text at EIP is 713 // unreadable this code will loop infinitely until the stack is exausted. 714 // The key to diagnosis in this case is to look for the bottom signal handler 715 // frame. 716 717 if(! IgnoreLibthreadGPFault) { 718 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 719 const unsigned char *p = 720 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 721 722 // Expected instruction? 723 724 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 725 726 Atomic::inc(&ldtr_refresh); 727 728 // Infinite loop? 729 730 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 731 732 // No, force scheduling to get a fresh view of the LDTR 733 734 if(poll(NULL, 0, 10) == 0) { 735 736 // Retry the move 737 738 return false; 739 } 740 } 741 } 742 } 743 } 744 #endif // !AMD64 745 746 if (!abort_if_unrecognized) { 747 // caller wants another chance, so give it to him 748 return false; 749 } 750 751 if (!os::Solaris::libjsig_is_loaded) { 752 struct sigaction oldAct; 753 sigaction(sig, (struct sigaction *)0, &oldAct); 754 if (oldAct.sa_sigaction != signalHandler) { 755 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 756 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 757 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand); 758 } 759 } 760 761 if (pc == NULL && uc != NULL) { 762 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 763 } 764 765 // unmask current signal 766 sigset_t newset; 767 sigemptyset(&newset); 768 sigaddset(&newset, sig); 769 sigprocmask(SIG_UNBLOCK, &newset, NULL); 770 771 // Determine which sort of error to throw. Out of swap may signal 772 // on the thread stack, which could get a mapping error when touched. 773 address addr = (address) info->si_addr; 774 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) { 775 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack."); 776 } 777 778 VMError::report_and_die(t, sig, pc, info, ucVoid); 779 780 ShouldNotReachHere(); 781 return false; 782 } 783 784 void os::print_context(outputStream *st, const void *context) { 785 if (context == NULL) return; 786 787 const ucontext_t *uc = (const ucontext_t*)context; 788 st->print_cr("Registers:"); 789 #ifdef AMD64 790 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 791 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 792 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 793 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 794 st->cr(); 795 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 796 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 797 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 798 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 799 st->cr(); 800 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 801 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 802 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 803 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 804 st->cr(); 805 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 806 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 807 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 808 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 809 st->cr(); 810 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 811 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 812 #else 813 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 814 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 815 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 816 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 817 st->cr(); 818 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 819 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 820 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 821 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 822 st->cr(); 823 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 824 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 825 #endif // AMD64 826 st->cr(); 827 st->cr(); 828 829 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 830 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 831 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 832 st->cr(); 833 834 // Note: it may be unsafe to inspect memory near pc. For example, pc may 835 // point to garbage if entry point in an nmethod is corrupted. Leave 836 // this at the end, and hope for the best. 837 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 838 address pc = epc.pc(); 839 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 840 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 841 } 842 843 void os::print_register_info(outputStream *st, const void *context) { 844 if (context == NULL) return; 845 846 const ucontext_t *uc = (const ucontext_t*)context; 847 848 st->print_cr("Register to memory mapping:"); 849 st->cr(); 850 851 // this is horrendously verbose but the layout of the registers in the 852 // context does not match how we defined our abstract Register set, so 853 // we can't just iterate through the gregs area 854 855 // this is only for the "general purpose" registers 856 857 #ifdef AMD64 858 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]); 859 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]); 860 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]); 861 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]); 862 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]); 863 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]); 864 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]); 865 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]); 866 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]); 867 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]); 868 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]); 869 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]); 870 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]); 871 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]); 872 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]); 873 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]); 874 #else 875 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]); 876 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]); 877 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]); 878 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]); 879 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]); 880 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]); 881 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]); 882 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]); 883 #endif 884 885 st->cr(); 886 } 887 888 889 #ifdef AMD64 890 void os::Solaris::init_thread_fpu_state(void) { 891 // Nothing to do 892 } 893 #else 894 // From solaris_i486.s 895 extern "C" void fixcw(); 896 897 void os::Solaris::init_thread_fpu_state(void) { 898 // Set fpu to 53 bit precision. This happens too early to use a stub. 899 fixcw(); 900 } 901 902 // These routines are the initial value of atomic_xchg_entry(), 903 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 904 // until initialization is complete. 905 // TODO - replace with .il implementation when compiler supports it. 906 907 typedef jint xchg_func_t (jint, volatile jint*); 908 typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 909 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 910 typedef jint add_func_t (jint, volatile jint*); 911 912 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 913 // try to use the stub: 914 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 915 916 if (func != NULL) { 917 os::atomic_xchg_func = func; 918 return (*func)(exchange_value, dest); 919 } 920 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 921 922 jint old_value = *dest; 923 *dest = exchange_value; 924 return old_value; 925 } 926 927 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 928 // try to use the stub: 929 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 930 931 if (func != NULL) { 932 os::atomic_cmpxchg_func = func; 933 return (*func)(exchange_value, dest, compare_value); 934 } 935 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 936 937 jint old_value = *dest; 938 if (old_value == compare_value) 939 *dest = exchange_value; 940 return old_value; 941 } 942 943 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 944 // try to use the stub: 945 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 946 947 if (func != NULL) { 948 os::atomic_cmpxchg_long_func = func; 949 return (*func)(exchange_value, dest, compare_value); 950 } 951 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 952 953 jlong old_value = *dest; 954 if (old_value == compare_value) 955 *dest = exchange_value; 956 return old_value; 957 } 958 959 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 960 // try to use the stub: 961 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 962 963 if (func != NULL) { 964 os::atomic_add_func = func; 965 return (*func)(add_value, dest); 966 } 967 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 968 969 return (*dest) += add_value; 970 } 971 972 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 973 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 974 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 975 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 976 977 extern "C" void _solaris_raw_setup_fpu(address ptr); 978 void os::setup_fpu() { 979 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 980 _solaris_raw_setup_fpu(fpu_cntrl); 981 } 982 #endif // AMD64 983 984 #ifndef PRODUCT 985 void os::verify_stack_alignment() { 986 #ifdef AMD64 987 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); 988 #endif 989 } 990 #endif 991 992 int os::extra_bang_size_in_bytes() { 993 // JDK-8050147 requires the full cache line bang for x86. 994 return VM_Version::L1_line_size(); 995 }