1 /* 2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2012, 2018 SAP SE. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 // no precompiled headers 27 #include "jvm.h" 28 #include "asm/assembler.inline.hpp" 29 #include "classfile/classLoader.hpp" 30 #include "classfile/systemDictionary.hpp" 31 #include "classfile/vmSymbols.hpp" 32 #include "code/codeCache.hpp" 33 #include "code/icBuffer.hpp" 34 #include "code/vtableStubs.hpp" 35 #include "interpreter/interpreter.hpp" 36 #include "memory/allocation.inline.hpp" 37 #include "nativeInst_ppc.hpp" 38 #include "os_share_linux.hpp" 39 #include "prims/jniFastGetField.hpp" 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.inline.hpp" 45 #include "runtime/java.hpp" 46 #include "runtime/javaCalls.hpp" 47 #include "runtime/mutexLocker.hpp" 48 #include "runtime/osThread.hpp" 49 #include "runtime/safepointMechanism.hpp" 50 #include "runtime/sharedRuntime.hpp" 51 #include "runtime/stubRoutines.hpp" 52 #include "runtime/thread.inline.hpp" 53 #include "runtime/timer.hpp" 54 #include "utilities/debug.hpp" 55 #include "utilities/events.hpp" 56 #include "utilities/vmError.hpp" 57 58 // put OS-includes here 59 # include <sys/types.h> 60 # include <sys/mman.h> 61 # include <pthread.h> 62 # include <signal.h> 63 # include <errno.h> 64 # include <dlfcn.h> 65 # include <stdlib.h> 66 # include <stdio.h> 67 # include <unistd.h> 68 # include <sys/resource.h> 69 # include <pthread.h> 70 # include <sys/stat.h> 71 # include <sys/time.h> 72 # include <sys/utsname.h> 73 # include <sys/socket.h> 74 # include <sys/wait.h> 75 # include <pwd.h> 76 # include <poll.h> 77 # include <ucontext.h> 78 79 80 address os::current_stack_pointer() { 81 intptr_t* csp; 82 83 // inline assembly `mr regno(csp), R1_SP': 84 __asm__ __volatile__ ("mr %0, 1":"=r"(csp):); 85 86 return (address) csp; 87 } 88 89 char* os::non_memory_address_word() { 90 // Must never look like an address returned by reserve_memory, 91 // even in its subfields (as defined by the CPU immediate fields, 92 // if the CPU splits constants across multiple instructions). 93 94 return (char*) -1; 95 } 96 97 // Frame information (pc, sp, fp) retrieved via ucontext 98 // always looks like a C-frame according to the frame 99 // conventions in frame_ppc64.hpp. 100 address os::Linux::ucontext_get_pc(const ucontext_t * uc) { 101 // On powerpc64, ucontext_t is not selfcontained but contains 102 // a pointer to an optional substructure (mcontext_t.regs) containing the volatile 103 // registers - NIP, among others. 104 // This substructure may or may not be there depending where uc came from: 105 // - if uc was handed over as the argument to a sigaction handler, a pointer to the 106 // substructure was provided by the kernel when calling the signal handler, and 107 // regs->nip can be accessed. 108 // - if uc was filled by getcontext(), it is undefined - getcontext() does not fill 109 // it because the volatile registers are not needed to make setcontext() work. 110 // Hopefully it was zero'd out beforehand. 111 guarantee(uc->uc_mcontext.regs != NULL, "only use ucontext_get_pc in sigaction context"); 112 return (address)uc->uc_mcontext.regs->nip; 113 } 114 115 // modify PC in ucontext. 116 // Note: Only use this for an ucontext handed down to a signal handler. See comment 117 // in ucontext_get_pc. 118 void os::Linux::ucontext_set_pc(ucontext_t * uc, address pc) { 119 guarantee(uc->uc_mcontext.regs != NULL, "only use ucontext_set_pc in sigaction context"); 120 uc->uc_mcontext.regs->nip = (unsigned long)pc; 121 } 122 123 static address ucontext_get_lr(const ucontext_t * uc) { 124 return (address)uc->uc_mcontext.regs->link; 125 } 126 127 intptr_t* os::Linux::ucontext_get_sp(const ucontext_t * uc) { 128 return (intptr_t*)uc->uc_mcontext.regs->gpr[1/*REG_SP*/]; 129 } 130 131 intptr_t* os::Linux::ucontext_get_fp(const ucontext_t * uc) { 132 return NULL; 133 } 134 135 ExtendedPC os::fetch_frame_from_context(const void* ucVoid, 136 intptr_t** ret_sp, intptr_t** ret_fp) { 137 138 ExtendedPC epc; 139 const ucontext_t* uc = (const ucontext_t*)ucVoid; 140 141 if (uc != NULL) { 142 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc)); 143 if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc); 144 if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc); 145 } else { 146 // construct empty ExtendedPC for return value checking 147 epc = ExtendedPC(NULL); 148 if (ret_sp) *ret_sp = (intptr_t *)NULL; 149 if (ret_fp) *ret_fp = (intptr_t *)NULL; 150 } 151 152 return epc; 153 } 154 155 frame os::fetch_frame_from_context(const void* ucVoid) { 156 intptr_t* sp; 157 intptr_t* fp; 158 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 159 return frame(sp, epc.pc()); 160 } 161 162 bool os::Linux::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) { 163 address pc = (address) os::Linux::ucontext_get_pc(uc); 164 if (Interpreter::contains(pc)) { 165 // Interpreter performs stack banging after the fixed frame header has 166 // been generated while the compilers perform it before. To maintain 167 // semantic consistency between interpreted and compiled frames, the 168 // method returns the Java sender of the current frame. 169 *fr = os::fetch_frame_from_context(uc); 170 if (!fr->is_first_java_frame()) { 171 assert(fr->safe_for_sender(thread), "Safety check"); 172 *fr = fr->java_sender(); 173 } 174 } else { 175 // More complex code with compiled code. 176 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above"); 177 CodeBlob* cb = CodeCache::find_blob(pc); 178 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) { 179 // Not sure where the pc points to, fallback to default 180 // stack overflow handling. In compiled code, we bang before 181 // the frame is complete. 182 return false; 183 } else { 184 intptr_t* sp = os::Linux::ucontext_get_sp(uc); 185 address lr = ucontext_get_lr(uc); 186 *fr = frame(sp, lr); 187 if (!fr->is_java_frame()) { 188 assert(fr->safe_for_sender(thread), "Safety check"); 189 assert(!fr->is_first_frame(), "Safety check"); 190 *fr = fr->java_sender(); 191 } 192 } 193 } 194 assert(fr->is_java_frame(), "Safety check"); 195 return true; 196 } 197 198 frame os::get_sender_for_C_frame(frame* fr) { 199 if (*fr->sp() == 0) { 200 // fr is the last C frame 201 return frame(NULL, NULL); 202 } 203 return frame(fr->sender_sp(), fr->sender_pc()); 204 } 205 206 207 frame os::current_frame() { 208 intptr_t* csp = (intptr_t*) *((intptr_t*) os::current_stack_pointer()); 209 // hack. 210 frame topframe(csp, (address)0x8); 211 // Return sender of sender of current topframe which hopefully 212 // both have pc != NULL. 213 frame tmp = os::get_sender_for_C_frame(&topframe); 214 return os::get_sender_for_C_frame(&tmp); 215 } 216 217 // Utility functions 218 219 extern "C" JNIEXPORT int 220 JVM_handle_linux_signal(int sig, 221 siginfo_t* info, 222 void* ucVoid, 223 int abort_if_unrecognized) { 224 ucontext_t* uc = (ucontext_t*) ucVoid; 225 226 Thread* t = Thread::current_or_null_safe(); 227 228 SignalHandlerMark shm(t); 229 230 // Note: it's not uncommon that JNI code uses signal/sigset to install 231 // then restore certain signal handler (e.g. to temporarily block SIGPIPE, 232 // or have a SIGILL handler when detecting CPU type). When that happens, 233 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To 234 // avoid unnecessary crash when libjsig is not preloaded, try handle signals 235 // that do not require siginfo/ucontext first. 236 237 if (sig == SIGPIPE) { 238 if (os::Linux::chained_handler(sig, info, ucVoid)) { 239 return true; 240 } else { 241 // Ignoring SIGPIPE - see bugs 4229104 242 return true; 243 } 244 } 245 246 // Make the signal handler transaction-aware by checking the existence of a 247 // second (transactional) context with MSR TS bits active. If the signal is 248 // caught during a transaction, then just return to the HTM abort handler. 249 // Please refer to Linux kernel document powerpc/transactional_memory.txt, 250 // section "Signals". 251 if (uc && uc->uc_link) { 252 ucontext_t* second_uc = uc->uc_link; 253 254 // MSR TS bits are 29 and 30 (Power ISA, v2.07B, Book III-S, pp. 857-858, 255 // 3.2.1 "Machine State Register"), however note that ISA notation for bit 256 // numbering is MSB 0, so for normal bit numbering (LSB 0) they come to be 257 // bits 33 and 34. It's not related to endianness, just a notation matter. 258 if (second_uc->uc_mcontext.regs->msr & 0x600000000) { 259 if (TraceTraps) { 260 tty->print_cr("caught signal in transaction, " 261 "ignoring to jump to abort handler"); 262 } 263 // Return control to the HTM abort handler. 264 return true; 265 } 266 } 267 268 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT 269 if ((sig == SIGSEGV || sig == SIGBUS) && info != NULL && info->si_addr == g_assert_poison) { 270 handle_assert_poison_fault(ucVoid, info->si_addr); 271 return 1; 272 } 273 #endif 274 275 JavaThread* thread = NULL; 276 VMThread* vmthread = NULL; 277 if (os::Linux::signal_handlers_are_installed) { 278 if (t != NULL) { 279 if(t->is_Java_thread()) { 280 thread = (JavaThread*)t; 281 } else if(t->is_VM_thread()) { 282 vmthread = (VMThread *)t; 283 } 284 } 285 } 286 287 // Moved SafeFetch32 handling outside thread!=NULL conditional block to make 288 // it work if no associated JavaThread object exists. 289 if (uc) { 290 address const pc = os::Linux::ucontext_get_pc(uc); 291 if (pc && StubRoutines::is_safefetch_fault(pc)) { 292 os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc)); 293 return true; 294 } 295 } 296 297 // decide if this trap can be handled by a stub 298 address stub = NULL; 299 address pc = NULL; 300 301 //%note os_trap_1 302 if (info != NULL && uc != NULL && thread != NULL) { 303 pc = (address) os::Linux::ucontext_get_pc(uc); 304 305 // Handle ALL stack overflow variations here 306 if (sig == SIGSEGV) { 307 // Si_addr may not be valid due to a bug in the linux-ppc64 kernel (see 308 // comment below). Use get_stack_bang_address instead of si_addr. 309 address addr = ((NativeInstruction*)pc)->get_stack_bang_address(uc); 310 311 // Check if fault address is within thread stack. 312 if (thread->on_local_stack(addr)) { 313 // stack overflow 314 if (thread->in_stack_yellow_reserved_zone(addr)) { 315 if (thread->thread_state() == _thread_in_Java) { 316 if (thread->in_stack_reserved_zone(addr)) { 317 frame fr; 318 if (os::Linux::get_frame_at_stack_banging_point(thread, uc, &fr)) { 319 assert(fr.is_java_frame(), "Must be a Javac frame"); 320 frame activation = 321 SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr); 322 if (activation.sp() != NULL) { 323 thread->disable_stack_reserved_zone(); 324 if (activation.is_interpreted_frame()) { 325 thread->set_reserved_stack_activation((address)activation.fp()); 326 } else { 327 thread->set_reserved_stack_activation((address)activation.unextended_sp()); 328 } 329 return 1; 330 } 331 } 332 } 333 // Throw a stack overflow exception. 334 // Guard pages will be reenabled while unwinding the stack. 335 thread->disable_stack_yellow_reserved_zone(); 336 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 337 } else { 338 // Thread was in the vm or native code. Return and try to finish. 339 thread->disable_stack_yellow_reserved_zone(); 340 return 1; 341 } 342 } else if (thread->in_stack_red_zone(addr)) { 343 // Fatal red zone violation. Disable the guard pages and fall through 344 // to handle_unexpected_exception way down below. 345 thread->disable_stack_red_zone(); 346 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 347 348 // This is a likely cause, but hard to verify. Let's just print 349 // it as a hint. 350 tty->print_raw_cr("Please check if any of your loaded .so files has " 351 "enabled executable stack (see man page execstack(8))"); 352 } else { 353 // Accessing stack address below sp may cause SEGV if current 354 // thread has MAP_GROWSDOWN stack. This should only happen when 355 // current thread was created by user code with MAP_GROWSDOWN flag 356 // and then attached to VM. See notes in os_linux.cpp. 357 if (thread->osthread()->expanding_stack() == 0) { 358 thread->osthread()->set_expanding_stack(); 359 if (os::Linux::manually_expand_stack(thread, addr)) { 360 thread->osthread()->clear_expanding_stack(); 361 return 1; 362 } 363 thread->osthread()->clear_expanding_stack(); 364 } else { 365 fatal("recursive segv. expanding stack."); 366 } 367 } 368 } 369 } 370 371 if (thread->thread_state() == _thread_in_Java) { 372 // Java thread running in Java code => find exception handler if any 373 // a fault inside compiled code, the interpreter, or a stub 374 375 // A VM-related SIGILL may only occur if we are not in the zero page. 376 // On AIX, we get a SIGILL if we jump to 0x0 or to somewhere else 377 // in the zero page, because it is filled with 0x0. We ignore 378 // explicit SIGILLs in the zero page. 379 if (sig == SIGILL && (pc < (address) 0x200)) { 380 if (TraceTraps) { 381 tty->print_raw_cr("SIGILL happened inside zero page."); 382 } 383 goto report_and_die; 384 } 385 386 CodeBlob *cb = NULL; 387 // Handle signal from NativeJump::patch_verified_entry(). 388 if (( TrapBasedNotEntrantChecks && sig == SIGTRAP && nativeInstruction_at(pc)->is_sigtrap_zombie_not_entrant()) || 389 (!TrapBasedNotEntrantChecks && sig == SIGILL && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant())) { 390 if (TraceTraps) { 391 tty->print_cr("trap: zombie_not_entrant (%s)", (sig == SIGTRAP) ? "SIGTRAP" : "SIGILL"); 392 } 393 stub = SharedRuntime::get_handle_wrong_method_stub(); 394 } 395 396 else if (sig == ((SafepointMechanism::uses_thread_local_poll() && USE_POLL_BIT_ONLY) ? SIGTRAP : SIGSEGV) && 397 // A linux-ppc64 kernel before 2.6.6 doesn't set si_addr on some segfaults 398 // in 64bit mode (cf. http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.6), 399 // especially when we try to read from the safepoint polling page. So the check 400 // (address)info->si_addr == os::get_standard_polling_page() 401 // doesn't work for us. We use: 402 ((NativeInstruction*)pc)->is_safepoint_poll() && 403 CodeCache::contains((void*) pc) && 404 ((cb = CodeCache::find_blob(pc)) != NULL) && 405 cb->is_compiled()) { 406 if (TraceTraps) { 407 tty->print_cr("trap: safepoint_poll at " INTPTR_FORMAT " (%s)", p2i(pc), 408 (SafepointMechanism::uses_thread_local_poll() && USE_POLL_BIT_ONLY) ? "SIGTRAP" : "SIGSEGV"); 409 } 410 stub = SharedRuntime::get_poll_stub(pc); 411 } 412 413 // SIGTRAP-based ic miss check in compiled code. 414 else if (sig == SIGTRAP && TrapBasedICMissChecks && 415 nativeInstruction_at(pc)->is_sigtrap_ic_miss_check()) { 416 if (TraceTraps) { 417 tty->print_cr("trap: ic_miss_check at " INTPTR_FORMAT " (SIGTRAP)", p2i(pc)); 418 } 419 stub = SharedRuntime::get_ic_miss_stub(); 420 } 421 422 // SIGTRAP-based implicit null check in compiled code. 423 else if (sig == SIGTRAP && TrapBasedNullChecks && 424 nativeInstruction_at(pc)->is_sigtrap_null_check()) { 425 if (TraceTraps) { 426 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGTRAP)", p2i(pc)); 427 } 428 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 429 } 430 431 // SIGSEGV-based implicit null check in compiled code. 432 else if (sig == SIGSEGV && ImplicitNullChecks && 433 CodeCache::contains((void*) pc) && 434 MacroAssembler::uses_implicit_null_check(info->si_addr)) { 435 if (TraceTraps) { 436 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGSEGV)", p2i(pc)); 437 } 438 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 439 } 440 441 #ifdef COMPILER2 442 // SIGTRAP-based implicit range check in compiled code. 443 else if (sig == SIGTRAP && TrapBasedRangeChecks && 444 nativeInstruction_at(pc)->is_sigtrap_range_check()) { 445 if (TraceTraps) { 446 tty->print_cr("trap: range_check at " INTPTR_FORMAT " (SIGTRAP)", p2i(pc)); 447 } 448 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 449 } 450 #endif 451 else if (sig == SIGBUS) { 452 // BugId 4454115: A read from a MappedByteBuffer can fault here if the 453 // underlying file has been truncated. Do not crash the VM in such a case. 454 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 455 CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL; 456 if (nm != NULL && nm->has_unsafe_access()) { 457 address next_pc = pc + 4; 458 next_pc = SharedRuntime::handle_unsafe_access(thread, next_pc); 459 os::Linux::ucontext_set_pc(uc, next_pc); 460 return true; 461 } 462 } 463 } 464 465 else { // thread->thread_state() != _thread_in_Java 466 if (sig == SIGILL && VM_Version::is_determine_features_test_running()) { 467 // SIGILL must be caused by VM_Version::determine_features(). 468 *(int *)pc = 0; // patch instruction to 0 to indicate that it causes a SIGILL, 469 // flushing of icache is not necessary. 470 stub = pc + 4; // continue with next instruction. 471 } 472 else if (thread->thread_state() == _thread_in_vm && 473 sig == SIGBUS && thread->doing_unsafe_access()) { 474 address next_pc = pc + 4; 475 next_pc = SharedRuntime::handle_unsafe_access(thread, next_pc); 476 os::Linux::ucontext_set_pc(uc, pc + 4); 477 return true; 478 } 479 } 480 481 // Check to see if we caught the safepoint code in the 482 // process of write protecting the memory serialization page. 483 // It write enables the page immediately after protecting it 484 // so we can just return to retry the write. 485 if ((sig == SIGSEGV) && 486 // Si_addr may not be valid due to a bug in the linux-ppc64 kernel (see comment above). 487 // Use is_memory_serialization instead of si_addr. 488 ((NativeInstruction*)pc)->is_memory_serialization(thread, ucVoid)) { 489 // Synchronization problem in the pseudo memory barrier code (bug id 6546278) 490 // Block current thread until the memory serialize page permission restored. 491 os::block_on_serialize_page_trap(); 492 return true; 493 } 494 } 495 496 if (stub != NULL) { 497 // Save all thread context in case we need to restore it. 498 if (thread != NULL) thread->set_saved_exception_pc(pc); 499 os::Linux::ucontext_set_pc(uc, stub); 500 return true; 501 } 502 503 // signal-chaining 504 if (os::Linux::chained_handler(sig, info, ucVoid)) { 505 return true; 506 } 507 508 if (!abort_if_unrecognized) { 509 // caller wants another chance, so give it to him 510 return false; 511 } 512 513 if (pc == NULL && uc != NULL) { 514 pc = os::Linux::ucontext_get_pc(uc); 515 } 516 517 report_and_die: 518 // unmask current signal 519 sigset_t newset; 520 sigemptyset(&newset); 521 sigaddset(&newset, sig); 522 sigprocmask(SIG_UNBLOCK, &newset, NULL); 523 524 VMError::report_and_die(t, sig, pc, info, ucVoid); 525 526 ShouldNotReachHere(); 527 return false; 528 } 529 530 void os::Linux::init_thread_fpu_state(void) { 531 // Disable FP exceptions. 532 __asm__ __volatile__ ("mtfsfi 6,0"); 533 } 534 535 int os::Linux::get_fpu_control_word(void) { 536 // x86 has problems with FPU precision after pthread_cond_timedwait(). 537 // nothing to do on ppc64. 538 return 0; 539 } 540 541 void os::Linux::set_fpu_control_word(int fpu_control) { 542 // x86 has problems with FPU precision after pthread_cond_timedwait(). 543 // nothing to do on ppc64. 544 } 545 546 //////////////////////////////////////////////////////////////////////////////// 547 // thread stack 548 549 // Minimum usable stack sizes required to get to user code. Space for 550 // HotSpot guard pages is added later. 551 size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K; 552 size_t os::Posix::_java_thread_min_stack_allowed = 64 * K; 553 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K; 554 555 // Return default stack size for thr_type. 556 size_t os::Posix::default_stack_size(os::ThreadType thr_type) { 557 // Default stack size (compiler thread needs larger stack). 558 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K); 559 return s; 560 } 561 562 ///////////////////////////////////////////////////////////////////////////// 563 // helper functions for fatal error handler 564 565 void os::print_context(outputStream *st, const void *context) { 566 if (context == NULL) return; 567 568 const ucontext_t* uc = (const ucontext_t*)context; 569 570 st->print_cr("Registers:"); 571 st->print("pc =" INTPTR_FORMAT " ", uc->uc_mcontext.regs->nip); 572 st->print("lr =" INTPTR_FORMAT " ", uc->uc_mcontext.regs->link); 573 st->print("ctr=" INTPTR_FORMAT " ", uc->uc_mcontext.regs->ctr); 574 st->cr(); 575 for (int i = 0; i < 32; i++) { 576 st->print("r%-2d=" INTPTR_FORMAT " ", i, uc->uc_mcontext.regs->gpr[i]); 577 if (i % 3 == 2) st->cr(); 578 } 579 st->cr(); 580 st->cr(); 581 582 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc); 583 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", p2i(sp)); 584 print_hex_dump(st, (address)sp, (address)(sp + 128), sizeof(intptr_t)); 585 st->cr(); 586 587 // Note: it may be unsafe to inspect memory near pc. For example, pc may 588 // point to garbage if entry point in an nmethod is corrupted. Leave 589 // this at the end, and hope for the best. 590 address pc = os::Linux::ucontext_get_pc(uc); 591 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc)); 592 print_hex_dump(st, pc - 64, pc + 64, /*instrsize=*/4); 593 st->cr(); 594 } 595 596 void os::print_register_info(outputStream *st, const void *context) { 597 if (context == NULL) return; 598 599 const ucontext_t *uc = (const ucontext_t*)context; 600 601 st->print_cr("Register to memory mapping:"); 602 st->cr(); 603 604 st->print("pc ="); print_location(st, (intptr_t)uc->uc_mcontext.regs->nip); 605 st->print("lr ="); print_location(st, (intptr_t)uc->uc_mcontext.regs->link); 606 st->print("ctr ="); print_location(st, (intptr_t)uc->uc_mcontext.regs->ctr); 607 for (int i = 0; i < 32; i++) { 608 st->print("r%-2d=", i); 609 print_location(st, uc->uc_mcontext.regs->gpr[i]); 610 } 611 st->cr(); 612 } 613 614 extern "C" { 615 int SpinPause() { 616 return 0; 617 } 618 } 619 620 #ifndef PRODUCT 621 void os::verify_stack_alignment() { 622 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); 623 } 624 #endif 625 626 int os::extra_bang_size_in_bytes() { 627 // PPC does not require the additional stack bang. 628 return 0; 629 }