1 /*
   2  * Copyright (c) 1999, 2018, 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 "macroAssembler_sparc.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_sparc.hpp"
  38 #include "os_share_solaris.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/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 # include <signal.h>        // needed first to avoid name collision for "std" with SC 5.0
  57 
  58 // put OS-includes here
  59 # include <sys/types.h>
  60 # include <sys/mman.h>
  61 # include <pthread.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/lwp.h>
  75 # include <poll.h>
  76 # include <sys/lwp.h>
  77 
  78 # define _STRUCTURED_PROC 1  //  this gets us the new structured proc interfaces of 5.6 & later
  79 # include <sys/procfs.h>     //  see comment in <sys/procfs.h>
  80 
  81 #define MAX_PATH (2 * K)
  82 
  83 // Minimum usable stack sizes required to get to user code. Space for
  84 // HotSpot guard pages is added later.
  85 size_t os::Posix::_compiler_thread_min_stack_allowed = 104 * K;
  86 size_t os::Posix::_java_thread_min_stack_allowed = 86 * K;
  87 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
  88 
  89 int os::Solaris::max_register_window_saves_before_flushing() {
  90   // We should detect this at run time. For now, filling
  91   // in with a constant.
  92   return 8;
  93 }
  94 
  95 static void handle_unflushed_register_windows(gwindows_t *win) {
  96   int restore_count = win->wbcnt;
  97   int i;
  98 
  99   for(i=0; i<restore_count; i++) {
 100     address sp = ((address)win->spbuf[i]) + STACK_BIAS;
 101     address reg_win = (address)&win->wbuf[i];
 102     memcpy(sp,reg_win,sizeof(struct rwindow));
 103   }
 104 }
 105 
 106 char* os::non_memory_address_word() {
 107   // Must never look like an address returned by reserve_memory,
 108   // even in its subfields (as defined by the CPU immediate fields,
 109   // if the CPU splits constants across multiple instructions).
 110   // On SPARC, 0 != %hi(any real address), because there is no
 111   // allocation in the first 1Kb of the virtual address space.
 112   return (char*) 0;
 113 }
 114 
 115 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
 116 // There are issues with libthread giving out uc_links for different threads
 117 // on the same uc_link chain and bad or circular links.
 118 //
 119 bool os::Solaris::valid_ucontext(Thread* thread, const ucontext_t* valid, const ucontext_t* suspect) {
 120   if (valid >= suspect ||
 121       valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
 122       valid->uc_stack.ss_sp    != suspect->uc_stack.ss_sp    ||
 123       valid->uc_stack.ss_size  != suspect->uc_stack.ss_size) {
 124     DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
 125     return false;
 126   }
 127 
 128   if (thread->is_Java_thread()) {
 129     if (!valid_stack_address(thread, (address)suspect)) {
 130       DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
 131       return false;
 132     }
 133     address _sp   = (address)((intptr_t)suspect->uc_mcontext.gregs[REG_SP] + STACK_BIAS);
 134     if (!valid_stack_address(thread, _sp) ||
 135         !frame::is_valid_stack_pointer(((JavaThread*)thread)->base_of_stack_pointer(), (intptr_t*)_sp)) {
 136       DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
 137       return false;
 138     }
 139   }
 140   return true;
 141 }
 142 
 143 // We will only follow one level of uc_link since there are libthread
 144 // issues with ucontext linking and it is better to be safe and just
 145 // let caller retry later.
 146 const ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
 147   const ucontext_t *uc) {
 148 
 149   const ucontext_t *retuc = NULL;
 150 
 151   // Sometimes the topmost register windows are not properly flushed.
 152   // i.e., if the kernel would have needed to take a page fault
 153   if (uc != NULL && uc->uc_mcontext.gwins != NULL) {
 154     ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
 155   }
 156 
 157   if (uc != NULL) {
 158     if (uc->uc_link == NULL) {
 159       // cannot validate without uc_link so accept current ucontext
 160       retuc = uc;
 161     } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
 162       // first ucontext is valid so try the next one
 163       uc = uc->uc_link;
 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         // the ucontext one level down is also valid so return it
 169         retuc = uc;
 170       }
 171     }
 172   }
 173   return retuc;
 174 }
 175 
 176 // Assumes ucontext is valid
 177 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(const ucontext_t *uc) {
 178   address pc = (address)uc->uc_mcontext.gregs[REG_PC];
 179   // set npc to zero to avoid using it for safepoint, good for profiling only
 180   return ExtendedPC(pc);
 181 }
 182 
 183 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) {
 184   uc->uc_mcontext.gregs [REG_PC]  = (greg_t) pc;
 185   uc->uc_mcontext.gregs [REG_nPC] = (greg_t) (pc + 4);
 186 }
 187 
 188 // Assumes ucontext is valid
 189 intptr_t* os::Solaris::ucontext_get_sp(const ucontext_t *uc) {
 190   return (intptr_t*)((intptr_t)uc->uc_mcontext.gregs[REG_SP] + STACK_BIAS);
 191 }
 192 
 193 // Solaris X86 only
 194 intptr_t* os::Solaris::ucontext_get_fp(const ucontext_t *uc) {
 195   ShouldNotReachHere();
 196   return NULL;
 197 }
 198 
 199 address os::Solaris::ucontext_get_pc(const ucontext_t *uc) {
 200   return (address) uc->uc_mcontext.gregs[REG_PC];
 201 }
 202 
 203 
 204 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
 205 // is currently interrupted by SIGPROF.
 206 //
 207 // ret_fp parameter is only used by Solaris X86.
 208 //
 209 // The difference between this and os::fetch_frame_from_context() is that
 210 // here we try to skip nested signal frames.
 211 // This method is also used for stack overflow signal handling.
 212 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
 213   const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
 214 
 215   assert(thread != NULL, "just checking");
 216   assert(ret_sp != NULL, "just checking");
 217   assert(ret_fp == NULL, "just checking");
 218 
 219   const ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
 220 
 221   return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
 222 }
 223 
 224 
 225 // ret_fp parameter is only used by Solaris X86.
 226 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
 227                     intptr_t** ret_sp, intptr_t** ret_fp) {
 228 
 229   ExtendedPC  epc;
 230   const ucontext_t *uc = (const ucontext_t*)ucVoid;
 231 
 232   if (uc != NULL) {
 233     epc = os::Solaris::ucontext_get_ExtendedPC(uc);
 234     if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
 235   } else {
 236     // construct empty ExtendedPC for return value checking
 237     epc = ExtendedPC(NULL);
 238     if (ret_sp) *ret_sp = (intptr_t *)NULL;
 239   }
 240 
 241   return epc;
 242 }
 243 
 244 frame os::fetch_frame_from_context(const void* ucVoid) {
 245   intptr_t* sp;
 246   intptr_t* fp;
 247   ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
 248   return frame(sp, frame::unpatchable, epc.pc());
 249 }
 250 
 251 frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) {
 252   intptr_t* sp;
 253   ExtendedPC epc = os::Solaris::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, NULL);
 254   return frame(sp, frame::unpatchable, epc.pc());
 255 }
 256 
 257 bool os::Solaris::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
 258   address pc = (address) os::Solaris::ucontext_get_pc(uc);
 259   if (Interpreter::contains(pc)) {
 260     *fr = os::fetch_frame_from_ucontext(thread, uc);
 261     if (!fr->is_first_java_frame()) {
 262       assert(fr->safe_for_sender(thread), "Safety check");
 263       *fr = fr->java_sender();
 264     }
 265   } else {
 266     // more complex code with compiled code
 267     assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
 268     CodeBlob* cb = CodeCache::find_blob(pc);
 269     if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
 270       // Not sure where the pc points to, fallback to default
 271       // stack overflow handling
 272       return false;
 273     } else {
 274       // Returned frame will be the caller of the method that faults on the stack bang.
 275       // Register window not yet rotated (happens at SAVE after stack bang), so there is no new
 276       // frame to go with the faulting PC. Using caller SP that is still in SP, and caller PC
 277       // that was written to O7 at call.
 278       intptr_t* sp = os::Solaris::ucontext_get_sp(uc);
 279       address pc = (address)uc->uc_mcontext.gregs[REG_O7];
 280       *fr = frame(sp, frame::unpatchable, pc);
 281 
 282       if (!fr->is_java_frame()) {
 283         assert(fr->safe_for_sender(thread), "Safety check");
 284         *fr = fr->java_sender();
 285       }
 286     }
 287   }
 288   assert(fr->is_java_frame(), "Safety check");
 289   return true;
 290 }
 291 
 292 frame os::get_sender_for_C_frame(frame* fr) {
 293   return frame(fr->sender_sp(), frame::unpatchable, fr->sender_pc());
 294 }
 295 
 296 // Returns an estimate of the current stack pointer. Result must be guaranteed to
 297 // point into the calling threads stack, and be no lower than the current stack
 298 // pointer.
 299 address os::current_stack_pointer() {
 300   volatile int dummy;
 301   address sp = (address)&dummy + 8;     // %%%% need to confirm if this is right
 302   return sp;
 303 }
 304 
 305 frame os::current_frame() {
 306   intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
 307   frame myframe(sp, frame::unpatchable,
 308                 CAST_FROM_FN_PTR(address, os::current_frame));
 309   if (os::is_first_C_frame(&myframe)) {
 310     // stack is not walkable
 311     return frame(NULL, NULL, false);
 312   } else {
 313     return os::get_sender_for_C_frame(&myframe);
 314   }
 315 }
 316 
 317 bool os::is_allocatable(size_t bytes) {
 318    return true;
 319 }
 320 
 321 extern "C" JNIEXPORT int
 322 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid,
 323                           int abort_if_unrecognized) {
 324   ucontext_t* uc = (ucontext_t*) ucVoid;
 325 
 326   Thread* t = Thread::current_or_null_safe();
 327 
 328   // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
 329   // (no destructors can be run)
 330   os::ThreadCrashProtection::check_crash_protection(sig, t);
 331 
 332   SignalHandlerMark shm(t);
 333 
 334   if(sig == SIGPIPE || sig == SIGXFSZ) {
 335     if (os::Solaris::chained_handler(sig, info, ucVoid)) {
 336       return true;
 337     } else {
 338       // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
 339       return true;
 340     }
 341   }
 342 
 343   JavaThread* thread = NULL;
 344   VMThread* vmthread = NULL;
 345   if (os::Solaris::signal_handlers_are_installed) {
 346     if (t != NULL ){
 347       if(t->is_Java_thread()) {
 348         thread = (JavaThread*)t;
 349       }
 350       else if(t->is_VM_thread()){
 351         vmthread = (VMThread *)t;
 352       }
 353     }
 354   }
 355 
 356   if (sig == ASYNC_SIGNAL) {
 357     if (thread || vmthread) {
 358       OSThread::SR_handler(t, uc);
 359       return true;
 360     } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
 361       return true;
 362     } else {
 363       // If ASYNC_SIGNAL not chained, and this is a non-vm and
 364       // non-java thread
 365       return true;
 366     }
 367   }
 368 
 369   if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
 370     // can't decode this kind of signal
 371     info = NULL;
 372   } else {
 373     assert(sig == info->si_signo, "bad siginfo");
 374   }
 375 
 376   // decide if this trap can be handled by a stub
 377   address stub = NULL;
 378 
 379   address pc          = NULL;
 380   address npc         = NULL;
 381 
 382   //%note os_trap_1
 383   if (info != NULL && uc != NULL && thread != NULL) {
 384     // factor me: getPCfromContext
 385     pc  = (address) uc->uc_mcontext.gregs[REG_PC];
 386     npc = (address) uc->uc_mcontext.gregs[REG_nPC];
 387 
 388     // SafeFetch() support
 389     if (StubRoutines::is_safefetch_fault(pc)) {
 390       os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
 391       return 1;
 392     }
 393 
 394     // Handle ALL stack overflow variations here
 395     if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
 396       address addr = (address) info->si_addr;
 397       if (thread->in_stack_yellow_reserved_zone(addr)) {
 398         // Sometimes the register windows are not properly flushed.
 399         if(uc->uc_mcontext.gwins != NULL) {
 400           ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
 401         }
 402         if (thread->thread_state() == _thread_in_Java) {
 403           if (thread->in_stack_reserved_zone(addr)) {
 404             frame fr;
 405             if (os::Solaris::get_frame_at_stack_banging_point(thread, uc, &fr)) {
 406               assert(fr.is_java_frame(), "Must be a Java frame");
 407               frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
 408               if (activation.sp() != NULL) {
 409                 thread->disable_stack_reserved_zone();
 410                 RegisterMap map(thread);
 411                 int frame_size = activation.frame_size(&map);
 412                 thread->set_reserved_stack_activation((address)(((address)activation.sp()) - STACK_BIAS));
 413                 return true;
 414               }
 415             }
 416           }
 417           // Throw a stack overflow exception.  Guard pages will be reenabled
 418           // while unwinding the stack.
 419           thread->disable_stack_yellow_reserved_zone();
 420           stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
 421         } else {
 422           // Thread was in the vm or native code.  Return and try to finish.
 423           thread->disable_stack_yellow_reserved_zone();
 424           return true;
 425         }
 426       } else if (thread->in_stack_red_zone(addr)) {
 427         // Fatal red zone violation.  Disable the guard pages and fall through
 428         // to handle_unexpected_exception way down below.
 429         thread->disable_stack_red_zone();
 430         tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
 431         // Sometimes the register windows are not properly flushed.
 432         if(uc->uc_mcontext.gwins != NULL) {
 433           ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
 434         }
 435       }
 436     }
 437 
 438 
 439     if (thread->thread_state() == _thread_in_vm) {
 440       if (sig == SIGBUS && thread->doing_unsafe_access()) {
 441         stub = SharedRuntime::handle_unsafe_access(thread, npc);
 442       }
 443     }
 444 
 445     else if (thread->thread_state() == _thread_in_Java) {
 446       // Java thread running in Java code => find exception handler if any
 447       // a fault inside compiled code, the interpreter, or a stub
 448 
 449       // Support Safepoint Polling
 450       if (sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
 451         stub = SharedRuntime::get_poll_stub(pc);
 452       }
 453 
 454       // Not needed on x86 solaris because verify_oops doesn't generate
 455       // SEGV/BUS like sparc does.
 456       if ( (sig == SIGSEGV || sig == SIGBUS)
 457            && pc >= MacroAssembler::_verify_oop_implicit_branch[0]
 458            && pc <  MacroAssembler::_verify_oop_implicit_branch[1] ) {
 459         stub     =  MacroAssembler::_verify_oop_implicit_branch[2];
 460         warning("fixed up memory fault in +VerifyOops at address " INTPTR_FORMAT, info->si_addr);
 461       }
 462 
 463       // This is not factored because on x86 solaris the patching for
 464       // zombies does not generate a SEGV.
 465       else if (sig == SIGSEGV && nativeInstruction_at(pc)->is_zombie()) {
 466         // zombie method (ld [%g0],%o7 instruction)
 467         stub = SharedRuntime::get_handle_wrong_method_stub();
 468 
 469         // At the stub it needs to look like a call from the caller of this
 470         // method (not a call from the segv site).
 471         pc = (address)uc->uc_mcontext.gregs[REG_O7];
 472       }
 473       else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
 474         // BugId 4454115: A read from a MappedByteBuffer can fault
 475         // here if the underlying file has been truncated.
 476         // Do not crash the VM in such a case.
 477         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
 478         CompiledMethod* nm = cb->as_compiled_method_or_null();
 479         if (nm != NULL && nm->has_unsafe_access()) {
 480           stub = SharedRuntime::handle_unsafe_access(thread, npc);
 481         }
 482       }
 483 
 484       else if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
 485         // integer divide by zero
 486         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
 487       }
 488       else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
 489         // floating-point divide by zero
 490         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
 491       }
 492 #ifdef COMPILER2
 493       else if (sig == SIGILL && nativeInstruction_at(pc)->is_ic_miss_trap()) {
 494 #ifdef ASSERT
 495   #ifdef TIERED
 496         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
 497         assert(cb->is_compiled_by_c2(), "Wrong compiler");
 498   #endif // TIERED
 499 #endif // ASSERT
 500         // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
 501         stub = SharedRuntime::get_ic_miss_stub();
 502         // At the stub it needs to look like a call from the caller of this
 503         // method (not a call from the segv site).
 504         pc = (address)uc->uc_mcontext.gregs[REG_O7];
 505       }
 506 #endif  // COMPILER2
 507 
 508       else if (sig == SIGSEGV && info->si_code > 0 && MacroAssembler::uses_implicit_null_check(info->si_addr)) {
 509         // Determination of interpreter/vtable stub/compiled code null exception
 510         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
 511       }
 512     }
 513 
 514     // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
 515     // and the heap gets shrunk before the field access.
 516     if ((sig == SIGSEGV) || (sig == SIGBUS)) {
 517       address addr = JNI_FastGetField::find_slowcase_pc(pc);
 518       if (addr != (address)-1) {
 519         stub = addr;
 520       }
 521     }
 522   }
 523 
 524   if (stub != NULL) {
 525     // save all thread context in case we need to restore it
 526 
 527     thread->set_saved_exception_pc(pc);
 528     thread->set_saved_exception_npc(npc);
 529 
 530     // simulate a branch to the stub (a "call" in the safepoint stub case)
 531     // factor me: setPC
 532     os::Solaris::ucontext_set_pc(uc, stub);
 533 
 534     return true;
 535   }
 536 
 537   // signal-chaining
 538   if (os::Solaris::chained_handler(sig, info, ucVoid)) {
 539     return true;
 540   }
 541 
 542   if (!abort_if_unrecognized) {
 543     // caller wants another chance, so give it to him
 544     return false;
 545   }
 546 
 547   if (!os::Solaris::libjsig_is_loaded) {
 548     struct sigaction oldAct;
 549     sigaction(sig, (struct sigaction *)0, &oldAct);
 550     if (oldAct.sa_sigaction != signalHandler) {
 551       void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
 552                                           : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
 553       warning("Unexpected Signal %d occurred under user-defined signal handler " INTPTR_FORMAT, sig, (intptr_t)sighand);
 554     }
 555   }
 556 
 557   if (pc == NULL && uc != NULL) {
 558     pc = (address) uc->uc_mcontext.gregs[REG_PC];
 559   }
 560 
 561   // Sometimes the register windows are not properly flushed.
 562   if(uc->uc_mcontext.gwins != NULL) {
 563     ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
 564   }
 565 
 566   // unmask current signal
 567   sigset_t newset;
 568   sigemptyset(&newset);
 569   sigaddset(&newset, sig);
 570   sigprocmask(SIG_UNBLOCK, &newset, NULL);
 571 
 572   // Determine which sort of error to throw.  Out of swap may signal
 573   // on the thread stack, which could get a mapping error when touched.
 574   address addr = (address) info->si_addr;
 575   if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) {
 576     vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack.");
 577   }
 578 
 579   VMError::report_and_die(t, sig, pc, info, ucVoid);
 580 
 581   ShouldNotReachHere();
 582   return false;
 583 }
 584 
 585 void os::print_context(outputStream *st, const void *context) {
 586   if (context == NULL) return;
 587 
 588   const ucontext_t *uc = (const ucontext_t*)context;
 589   st->print_cr("Registers:");
 590 
 591   st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
 592                " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
 593             uc->uc_mcontext.gregs[REG_G1],
 594             uc->uc_mcontext.gregs[REG_G2],
 595             uc->uc_mcontext.gregs[REG_G3],
 596             uc->uc_mcontext.gregs[REG_G4]);
 597   st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
 598                " G7=" INTPTR_FORMAT " Y=" INTPTR_FORMAT,
 599             uc->uc_mcontext.gregs[REG_G5],
 600             uc->uc_mcontext.gregs[REG_G6],
 601             uc->uc_mcontext.gregs[REG_G7],
 602             uc->uc_mcontext.gregs[REG_Y]);
 603   st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
 604                " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
 605                  uc->uc_mcontext.gregs[REG_O0],
 606                  uc->uc_mcontext.gregs[REG_O1],
 607                  uc->uc_mcontext.gregs[REG_O2],
 608                  uc->uc_mcontext.gregs[REG_O3]);
 609   st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
 610                " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
 611             uc->uc_mcontext.gregs[REG_O4],
 612             uc->uc_mcontext.gregs[REG_O5],
 613             uc->uc_mcontext.gregs[REG_O6],
 614             uc->uc_mcontext.gregs[REG_O7]);
 615 
 616 
 617   intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
 618   st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
 619                " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
 620                sp[L0->sp_offset_in_saved_window()],
 621                sp[L1->sp_offset_in_saved_window()],
 622                sp[L2->sp_offset_in_saved_window()],
 623                sp[L3->sp_offset_in_saved_window()]);
 624   st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
 625                " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
 626                sp[L4->sp_offset_in_saved_window()],
 627                sp[L5->sp_offset_in_saved_window()],
 628                sp[L6->sp_offset_in_saved_window()],
 629                sp[L7->sp_offset_in_saved_window()]);
 630   st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
 631                " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
 632                sp[I0->sp_offset_in_saved_window()],
 633                sp[I1->sp_offset_in_saved_window()],
 634                sp[I2->sp_offset_in_saved_window()],
 635                sp[I3->sp_offset_in_saved_window()]);
 636   st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
 637                " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
 638                sp[I4->sp_offset_in_saved_window()],
 639                sp[I5->sp_offset_in_saved_window()],
 640                sp[I6->sp_offset_in_saved_window()],
 641                sp[I7->sp_offset_in_saved_window()]);
 642 
 643   st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
 644             uc->uc_mcontext.gregs[REG_PC],
 645             uc->uc_mcontext.gregs[REG_nPC]);
 646   st->cr();
 647   st->cr();
 648 
 649   st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
 650   print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
 651   st->cr();
 652 
 653   // Note: it may be unsafe to inspect memory near pc. For example, pc may
 654   // point to garbage if entry point in an nmethod is corrupted. Leave
 655   // this at the end, and hope for the best.
 656   ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
 657   address pc = epc.pc();
 658   print_instructions(st, pc, sizeof(char));
 659   st->cr();
 660 }
 661 
 662 void os::print_register_info(outputStream *st, const void *context) {
 663   if (context == NULL) return;
 664 
 665   const ucontext_t *uc = (const ucontext_t*)context;
 666   intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
 667 
 668   st->print_cr("Register to memory mapping:");
 669   st->cr();
 670 
 671   // this is only for the "general purpose" registers
 672   st->print("G1="); print_location(st, uc->uc_mcontext.gregs[REG_G1]);
 673   st->print("G2="); print_location(st, uc->uc_mcontext.gregs[REG_G2]);
 674   st->print("G3="); print_location(st, uc->uc_mcontext.gregs[REG_G3]);
 675   st->print("G4="); print_location(st, uc->uc_mcontext.gregs[REG_G4]);
 676   st->print("G5="); print_location(st, uc->uc_mcontext.gregs[REG_G5]);
 677   st->print("G6="); print_location(st, uc->uc_mcontext.gregs[REG_G6]);
 678   st->print("G7="); print_location(st, uc->uc_mcontext.gregs[REG_G7]);
 679   st->cr();
 680 
 681   st->print("O0="); print_location(st, uc->uc_mcontext.gregs[REG_O0]);
 682   st->print("O1="); print_location(st, uc->uc_mcontext.gregs[REG_O1]);
 683   st->print("O2="); print_location(st, uc->uc_mcontext.gregs[REG_O2]);
 684   st->print("O3="); print_location(st, uc->uc_mcontext.gregs[REG_O3]);
 685   st->print("O4="); print_location(st, uc->uc_mcontext.gregs[REG_O4]);
 686   st->print("O5="); print_location(st, uc->uc_mcontext.gregs[REG_O5]);
 687   st->print("O6="); print_location(st, uc->uc_mcontext.gregs[REG_O6]);
 688   st->print("O7="); print_location(st, uc->uc_mcontext.gregs[REG_O7]);
 689   st->cr();
 690 
 691   st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
 692   st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
 693   st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
 694   st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
 695   st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
 696   st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
 697   st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
 698   st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
 699   st->cr();
 700 
 701   st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
 702   st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
 703   st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
 704   st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
 705   st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
 706   st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
 707   st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
 708   st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
 709   st->cr();
 710 }
 711 
 712 void os::Solaris::init_thread_fpu_state(void) {
 713     // Nothing needed on Sparc.
 714 }
 715 
 716 #ifndef PRODUCT
 717 void os::verify_stack_alignment() {
 718 }
 719 #endif
 720 
 721 int os::extra_bang_size_in_bytes() {
 722   // SPARC does not require an additional stack bang.
 723   return 0;
 724 }