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_linux.h"
35 #include "memory/allocation.inline.hpp"
36 #include "nativeInst_sparc.hpp"
37 #include "os_share_linux.hpp"
38 #include "prims/jniFastGetField.hpp"
39 #include "prims/jvm.h"
40 #include "prims/jvm_misc.hpp"
41 #include "runtime/arguments.hpp"
42 #include "runtime/extendedPC.hpp"
43 #include "runtime/frame.inline.hpp"
44 #include "runtime/interfaceSupport.hpp"
45 #include "runtime/java.hpp"
46 #include "runtime/javaCalls.hpp"
47 #include "runtime/mutexLocker.hpp"
48 #include "runtime/osThread.hpp"
49 #include "runtime/sharedRuntime.hpp"
50 #include "runtime/stubRoutines.hpp"
51 #include "runtime/thread.inline.hpp"
52 #include "runtime/timer.hpp"
53 #include "utilities/events.hpp"
54 #include "utilities/vmError.hpp"
55
56 // Linux/Sparc has rather obscure naming of registers in sigcontext
57 // different between 32 and 64 bits
58 #ifdef _LP64
59 #define SIG_PC(x) ((x)->sigc_regs.tpc)
60 #define SIG_NPC(x) ((x)->sigc_regs.tnpc)
61 #define SIG_REGS(x) ((x)->sigc_regs)
62 #else
63 #define SIG_PC(x) ((x)->si_regs.pc)
64 #define SIG_NPC(x) ((x)->si_regs.npc)
65 #define SIG_REGS(x) ((x)->si_regs)
66 #endif
67
68 // those are to reference registers in sigcontext
69 enum {
70 CON_G0 = 0,
71 CON_G1,
72 CON_G2,
73 CON_G3,
74 CON_G4,
75 CON_G5,
76 CON_G6,
77 CON_G7,
78 CON_O0,
79 CON_O1,
80 CON_O2,
81 CON_O3,
82 CON_O4,
83 CON_O5,
84 CON_O6,
85 CON_O7,
86 };
87
88 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
89 // currently interrupted by SIGPROF.
90 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested
91 // signal frames. Currently we don't do that on Linux, so it's the
92 // same as os::fetch_frame_from_context().
93 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
94 const ucontext_t* uc,
95 intptr_t** ret_sp,
96 intptr_t** ret_fp) {
97 assert(thread != NULL, "just checking");
98 assert(ret_sp != NULL, "just checking");
99 assert(ret_fp != NULL, "just checking");
100
101 return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
102 }
103
104 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
105 intptr_t** ret_sp,
106 intptr_t** ret_fp) {
107 const ucontext_t* uc = (const ucontext_t*) ucVoid;
108 ExtendedPC epc;
109
110 if (uc != NULL) {
111 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
112 if (ret_sp) {
113 *ret_sp = os::Linux::ucontext_get_sp(uc);
114 }
115 if (ret_fp) {
116 *ret_fp = (intptr_t*)NULL;
117 }
118 } else {
119 // construct empty ExtendedPC for return value checking
120 epc = ExtendedPC(NULL);
121 if (ret_sp) {
122 *ret_sp = (intptr_t*) NULL;
123 }
124 if (ret_fp) {
125 *ret_fp = (intptr_t*) NULL;
126 }
127 }
128
129 return epc;
130 }
131
132 frame os::fetch_frame_from_context(const void* ucVoid) {
133 intptr_t* sp;
134 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, NULL);
135 return frame(sp, frame::unpatchable, epc.pc());
136 }
137
138 frame os::get_sender_for_C_frame(frame* fr) {
139 return frame(fr->sender_sp(), frame::unpatchable, fr->sender_pc());
140 }
141
142 frame os::current_frame() {
143 intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
144 frame myframe(sp, frame::unpatchable,
145 CAST_FROM_FN_PTR(address, os::current_frame));
146 if (os::is_first_C_frame(&myframe)) {
147 // stack is not walkable
148 return frame(NULL, frame::unpatchable, NULL);
149 } else {
150 return os::get_sender_for_C_frame(&myframe);
151 }
152 }
153
154 address os::current_stack_pointer() {
155 register void *sp __asm__ ("sp");
156 return (address)sp;
157 }
158
159 char* os::non_memory_address_word() {
160 // Must never look like an address returned by reserve_memory,
161 // even in its subfields (as defined by the CPU immediate fields,
162 // if the CPU splits constants across multiple instructions).
163 // On SPARC, 0 != %hi(any real address), because there is no
164 // allocation in the first 1Kb of the virtual address space.
165 return (char*) 0;
166 }
167
168 void os::initialize_thread(Thread* thr) {}
169
170 void os::print_context(outputStream *st, const void *context) {
171 if (context == NULL) return;
172
173 const ucontext_t* uc = (const ucontext_t*)context;
174 sigcontext* sc = (sigcontext*)context;
175 st->print_cr("Registers:");
176
177 st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
178 " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
179 SIG_REGS(sc).u_regs[CON_G1],
180 SIG_REGS(sc).u_regs[CON_G2],
181 SIG_REGS(sc).u_regs[CON_G3],
182 SIG_REGS(sc).u_regs[CON_G4]);
183 st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
184 " G7=" INTPTR_FORMAT " Y=0x%x",
185 SIG_REGS(sc).u_regs[CON_G5],
186 SIG_REGS(sc).u_regs[CON_G6],
187 SIG_REGS(sc).u_regs[CON_G7],
188 SIG_REGS(sc).y);
189 st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
190 " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
191 SIG_REGS(sc).u_regs[CON_O0],
192 SIG_REGS(sc).u_regs[CON_O1],
193 SIG_REGS(sc).u_regs[CON_O2],
194 SIG_REGS(sc).u_regs[CON_O3]);
195 st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
196 " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
197 SIG_REGS(sc).u_regs[CON_O4],
198 SIG_REGS(sc).u_regs[CON_O5],
199 SIG_REGS(sc).u_regs[CON_O6],
200 SIG_REGS(sc).u_regs[CON_O7]);
201
202
203 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
204 st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
205 " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
206 sp[L0->sp_offset_in_saved_window()],
207 sp[L1->sp_offset_in_saved_window()],
208 sp[L2->sp_offset_in_saved_window()],
209 sp[L3->sp_offset_in_saved_window()]);
210 st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
211 " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
212 sp[L4->sp_offset_in_saved_window()],
213 sp[L5->sp_offset_in_saved_window()],
214 sp[L6->sp_offset_in_saved_window()],
215 sp[L7->sp_offset_in_saved_window()]);
216 st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
217 " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
218 sp[I0->sp_offset_in_saved_window()],
219 sp[I1->sp_offset_in_saved_window()],
220 sp[I2->sp_offset_in_saved_window()],
221 sp[I3->sp_offset_in_saved_window()]);
222 st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
223 " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
224 sp[I4->sp_offset_in_saved_window()],
225 sp[I5->sp_offset_in_saved_window()],
226 sp[I6->sp_offset_in_saved_window()],
227 sp[I7->sp_offset_in_saved_window()]);
228
229 st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
230 SIG_PC(sc),
231 SIG_NPC(sc));
232 st->cr();
233 st->cr();
234
235 st->print_cr("Top of Stack: (sp=" INTPTR_FORMAT ")", p2i(sp));
236 print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
237 st->cr();
238
239 // Note: it may be unsafe to inspect memory near pc. For example, pc may
240 // point to garbage if entry point in an nmethod is corrupted. Leave
241 // this at the end, and hope for the best.
242 address pc = os::Linux::ucontext_get_pc(uc);
243 st->print_cr("Instructions: (pc=" INTPTR_FORMAT ")", p2i(pc));
244 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
245 }
246
247
248 void os::print_register_info(outputStream *st, const void *context) {
249 if (context == NULL) return;
250
251 const ucontext_t *uc = (const ucontext_t*)context;
252 const sigcontext* sc = (const sigcontext*)context;
253 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
254
255 st->print_cr("Register to memory mapping:");
256 st->cr();
257
258 // this is only for the "general purpose" registers
259 st->print("G1="); print_location(st, SIG_REGS(sc).u_regs[CON_G1]);
260 st->print("G2="); print_location(st, SIG_REGS(sc).u_regs[CON_G2]);
261 st->print("G3="); print_location(st, SIG_REGS(sc).u_regs[CON_G3]);
262 st->print("G4="); print_location(st, SIG_REGS(sc).u_regs[CON_G4]);
263 st->print("G5="); print_location(st, SIG_REGS(sc).u_regs[CON_G5]);
264 st->print("G6="); print_location(st, SIG_REGS(sc).u_regs[CON_G6]);
265 st->print("G7="); print_location(st, SIG_REGS(sc).u_regs[CON_G7]);
266 st->cr();
267
268 st->print("O0="); print_location(st, SIG_REGS(sc).u_regs[CON_O0]);
269 st->print("O1="); print_location(st, SIG_REGS(sc).u_regs[CON_O1]);
270 st->print("O2="); print_location(st, SIG_REGS(sc).u_regs[CON_O2]);
271 st->print("O3="); print_location(st, SIG_REGS(sc).u_regs[CON_O3]);
272 st->print("O4="); print_location(st, SIG_REGS(sc).u_regs[CON_O4]);
273 st->print("O5="); print_location(st, SIG_REGS(sc).u_regs[CON_O5]);
274 st->print("O6="); print_location(st, SIG_REGS(sc).u_regs[CON_O6]);
275 st->print("O7="); print_location(st, SIG_REGS(sc).u_regs[CON_O7]);
276 st->cr();
277
278 st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
279 st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
280 st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
281 st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
282 st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
283 st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
284 st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
285 st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
286 st->cr();
287
288 st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
289 st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
290 st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
291 st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
292 st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
293 st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
294 st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
295 st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
296 st->cr();
297 }
298
299
300 address os::Linux::ucontext_get_pc(const ucontext_t* uc) {
301 return (address) SIG_PC((sigcontext*)uc);
302 }
303
304 void os::Linux::ucontext_set_pc(ucontext_t* uc, address pc) {
305 sigcontext* ctx = (sigcontext*) uc;
306 SIG_PC(ctx) = (intptr_t)pc;
307 SIG_NPC(ctx) = (intptr_t)(pc+4);
308 }
309
310 intptr_t* os::Linux::ucontext_get_sp(const ucontext_t *uc) {
311 return (intptr_t*)
312 ((intptr_t)SIG_REGS((sigcontext*)uc).u_regs[CON_O6] + STACK_BIAS);
313 }
314
315 // not used on Sparc
316 intptr_t* os::Linux::ucontext_get_fp(const ucontext_t *uc) {
317 ShouldNotReachHere();
318 return NULL;
319 }
320
321 // Utility functions
322
323 inline static bool checkPrefetch(sigcontext* uc, address pc) {
324 if (StubRoutines::is_safefetch_fault(pc)) {
325 os::Linux::ucontext_set_pc((ucontext_t*)uc, StubRoutines::continuation_for_safefetch_fault(pc));
326 return true;
327 }
328 return false;
329 }
330
331 inline static bool checkOverflow(sigcontext* uc,
332 address pc,
333 address addr,
334 JavaThread* thread,
335 address* stub) {
336 // check if fault address is within thread stack
337 if (thread->on_local_stack(addr)) {
338 // stack overflow
339 if (thread->in_stack_yellow_reserved_zone(addr)) {
340 thread->disable_stack_yellow_reserved_zone();
341 if (thread->thread_state() == _thread_in_Java) {
342 // Throw a stack overflow exception. Guard pages will be reenabled
343 // while unwinding the stack.
344 *stub =
345 SharedRuntime::continuation_for_implicit_exception(thread,
346 pc,
347 SharedRuntime::STACK_OVERFLOW);
348 } else {
349 // Thread was in the vm or native code. Return and try to finish.
350 return true;
351 }
352 } else if (thread->in_stack_red_zone(addr)) {
353 // Fatal red zone violation. Disable the guard pages and fall through
354 // to handle_unexpected_exception way down below.
355 thread->disable_stack_red_zone();
356 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
357
358 // This is a likely cause, but hard to verify. Let's just print
359 // it as a hint.
360 tty->print_raw_cr("Please check if any of your loaded .so files has "
361 "enabled executable stack (see man page execstack(8))");
362 } else {
363 // Accessing stack address below sp may cause SEGV if current
364 // thread has MAP_GROWSDOWN stack. This should only happen when
365 // current thread was created by user code with MAP_GROWSDOWN flag
366 // and then attached to VM. See notes in os_linux.cpp.
367 if (thread->osthread()->expanding_stack() == 0) {
368 thread->osthread()->set_expanding_stack();
369 if (os::Linux::manually_expand_stack(thread, addr)) {
370 thread->osthread()->clear_expanding_stack();
371 return true;
372 }
373 thread->osthread()->clear_expanding_stack();
374 } else {
375 fatal("recursive segv. expanding stack.");
376 }
377 }
378 }
379 return false;
380 }
381
382 inline static bool checkPollingPage(address pc, address fault, address* stub) {
383 if (fault == os::get_polling_page()) {
384 *stub = SharedRuntime::get_poll_stub(pc);
385 return true;
386 }
387 return false;
388 }
389
390 inline static bool checkByteBuffer(address pc, address npc, address* stub) {
391 // BugId 4454115: A read from a MappedByteBuffer can fault
392 // here if the underlying file has been truncated.
393 // Do not crash the VM in such a case.
394 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
395 CompiledMethod* nm = cb->as_compiled_method_or_null();
396 if (nm != NULL && nm->has_unsafe_access()) {
397 *stub = SharedRuntime::handle_unsafe_access(thread, npc);
398 return true;
399 }
400 return false;
401 }
402
403 inline static bool checkVerifyOops(address pc, address fault, address* stub) {
404 if (pc >= MacroAssembler::_verify_oop_implicit_branch[0]
405 && pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
406 *stub = MacroAssembler::_verify_oop_implicit_branch[2];
407 warning("fixed up memory fault in +VerifyOops at address "
408 INTPTR_FORMAT, p2i(fault));
409 return true;
410 }
411 return false;
412 }
413
414 inline static bool checkFPFault(address pc, int code,
415 JavaThread* thread, address* stub) {
416 if (code == FPE_INTDIV || code == FPE_FLTDIV) {
417 *stub =
418 SharedRuntime::
419 continuation_for_implicit_exception(thread,
420 pc,
421 SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
422 return true;
423 }
424 return false;
425 }
426
427 inline static bool checkNullPointer(address pc, intptr_t fault,
428 JavaThread* thread, address* stub) {
429 if (!MacroAssembler::needs_explicit_null_check(fault)) {
430 // Determination of interpreter/vtable stub/compiled code null
431 // exception
432 *stub =
433 SharedRuntime::
434 continuation_for_implicit_exception(thread, pc,
435 SharedRuntime::IMPLICIT_NULL);
436 return true;
437 }
438 return false;
439 }
440
441 inline static bool checkFastJNIAccess(address pc, address* stub) {
442 address addr = JNI_FastGetField::find_slowcase_pc(pc);
443 if (addr != (address)-1) {
444 *stub = addr;
445 return true;
446 }
447 return false;
448 }
449
450 inline static bool checkSerializePage(JavaThread* thread, address addr) {
451 return os::is_memory_serialize_page(thread, addr);
452 }
453
454 inline static bool checkZombie(sigcontext* uc, address* pc, address* stub) {
455 if (nativeInstruction_at(*pc)->is_zombie()) {
456 // zombie method (ld [%g0],%o7 instruction)
457 *stub = SharedRuntime::get_handle_wrong_method_stub();
458
459 // At the stub it needs to look like a call from the caller of this
460 // method (not a call from the segv site).
461 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
462 return true;
463 }
464 return false;
465 }
466
467 inline static bool checkICMiss(sigcontext* uc, address* pc, address* stub) {
468 #ifdef COMPILER2
469 if (nativeInstruction_at(*pc)->is_ic_miss_trap()) {
470 #ifdef ASSERT
471 #ifdef TIERED
472 CodeBlob* cb = CodeCache::find_blob_unsafe(*pc);
473 assert(cb->is_compiled_by_c2(), "Wrong compiler");
474 #endif // TIERED
475 #endif // ASSERT
476 // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
477 *stub = SharedRuntime::get_ic_miss_stub();
478 // At the stub it needs to look like a call from the caller of this
479 // method (not a call from the segv site).
480 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
481 return true;
482 }
483 #endif // COMPILER2
484 return false;
485 }
486
487 extern "C" JNIEXPORT int
488 JVM_handle_linux_signal(int sig,
489 siginfo_t* info,
490 void* ucVoid,
491 int abort_if_unrecognized) {
492 // in fact this isn't ucontext_t* at all, but struct sigcontext*
493 // but Linux porting layer uses ucontext_t, so to minimize code change
494 // we cast as needed
495 ucontext_t* ucFake = (ucontext_t*) ucVoid;
496 sigcontext* uc = (sigcontext*)ucVoid;
497
498 Thread* t = Thread::current_or_null_safe();
499
500 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
501 // (no destructors can be run)
502 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
503
504 SignalHandlerMark shm(t);
505
506 // Note: it's not uncommon that JNI code uses signal/sigset to install
507 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
508 // or have a SIGILL handler when detecting CPU type). When that happens,
509 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
510 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
511 // that do not require siginfo/ucontext first.
512
513 if (sig == SIGPIPE || sig == SIGXFSZ) {
514 // allow chained handler to go first
515 if (os::Linux::chained_handler(sig, info, ucVoid)) {
516 return true;
517 } else {
518 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
519 return true;
520 }
521 }
522
523 JavaThread* thread = NULL;
524 VMThread* vmthread = NULL;
525 if (os::Linux::signal_handlers_are_installed) {
526 if (t != NULL ){
527 if(t->is_Java_thread()) {
528 thread = (JavaThread*)t;
529 }
530 else if(t->is_VM_thread()){
531 vmthread = (VMThread *)t;
532 }
533 }
534 }
535
536 // decide if this trap can be handled by a stub
537 address stub = NULL;
538 address pc = NULL;
539 address npc = NULL;
540
541 //%note os_trap_1
542 if (info != NULL && uc != NULL && thread != NULL) {
543 pc = address(SIG_PC(uc));
544 npc = address(SIG_NPC(uc));
545
546 // Check to see if we caught the safepoint code in the
547 // process of write protecting the memory serialization page.
548 // It write enables the page immediately after protecting it
549 // so we can just return to retry the write.
550 if ((sig == SIGSEGV) && checkSerializePage(thread, (address)info->si_addr)) {
551 // Block current thread until the memory serialize page permission restored.
552 os::block_on_serialize_page_trap();
553 return 1;
554 }
555
556 if (checkPrefetch(uc, pc)) {
557 return 1;
558 }
559
560 // Handle ALL stack overflow variations here
561 if (sig == SIGSEGV) {
562 if (checkOverflow(uc, pc, (address)info->si_addr, thread, &stub)) {
563 return 1;
564 }
565 }
566
567 if (sig == SIGBUS &&
568 thread->thread_state() == _thread_in_vm &&
569 thread->doing_unsafe_access()) {
570 stub = SharedRuntime::handle_unsafe_access(thread, npc);
571 }
572
573 if (thread->thread_state() == _thread_in_Java) {
574 do {
575 // Java thread running in Java code => find exception handler if any
576 // a fault inside compiled code, the interpreter, or a stub
577
578 if ((sig == SIGSEGV) && checkPollingPage(pc, (address)info->si_addr, &stub)) {
579 break;
580 }
581
582 if ((sig == SIGBUS) && checkByteBuffer(pc, npc, &stub)) {
583 break;
584 }
585
586 if ((sig == SIGSEGV || sig == SIGBUS) &&
587 checkVerifyOops(pc, (address)info->si_addr, &stub)) {
588 break;
589 }
590
591 if ((sig == SIGSEGV) && checkZombie(uc, &pc, &stub)) {
592 break;
593 }
594
595 if ((sig == SIGILL) && checkICMiss(uc, &pc, &stub)) {
596 break;
597 }
598
599 if ((sig == SIGFPE) && checkFPFault(pc, info->si_code, thread, &stub)) {
600 break;
601 }
602
603 if ((sig == SIGSEGV) &&
604 checkNullPointer(pc, (intptr_t)info->si_addr, thread, &stub)) {
605 break;
606 }
607 } while (0);
608
609 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
610 // and the heap gets shrunk before the field access.
611 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
612 checkFastJNIAccess(pc, &stub);
613 }
614 }
615
616 if (stub != NULL) {
617 // save all thread context in case we need to restore it
618 thread->set_saved_exception_pc(pc);
619 thread->set_saved_exception_npc(npc);
620 os::Linux::ucontext_set_pc((ucontext_t*)uc, stub);
621 return true;
622 }
623 }
624
625 // signal-chaining
626 if (os::Linux::chained_handler(sig, info, ucVoid)) {
627 return true;
628 }
629
630 if (!abort_if_unrecognized) {
631 // caller wants another chance, so give it to him
632 return false;
633 }
634
635 if (pc == NULL && uc != NULL) {
636 pc = os::Linux::ucontext_get_pc((const ucontext_t*)uc);
637 }
638
639 // unmask current signal
640 sigset_t newset;
641 sigemptyset(&newset);
642 sigaddset(&newset, sig);
643 sigprocmask(SIG_UNBLOCK, &newset, NULL);
644
645 VMError::report_and_die(t, sig, pc, info, ucVoid);
646
647 ShouldNotReachHere();
648 return false;
649 }
650
651 void os::Linux::init_thread_fpu_state(void) {
652 // Nothing to do
653 }
654
655 int os::Linux::get_fpu_control_word() {
656 return 0;
657 }
658
659 void os::Linux::set_fpu_control_word(int fpu) {
660 // nothing
661 }
662
663 bool os::is_allocatable(size_t bytes) {
664 #ifdef _LP64
665 return true;
666 #else
667 if (bytes < 2 * G) {
668 return true;
669 }
670
671 char* addr = reserve_memory(bytes, NULL);
672
673 if (addr != NULL) {
674 release_memory(addr, bytes);
675 }
676
677 return addr != NULL;
678 #endif // _LP64
679 }
680
681 ///////////////////////////////////////////////////////////////////////////////
682 // thread stack
683
684 size_t os::Posix::_compiler_thread_min_stack_allowed = 128 * K;
685 size_t os::Posix::_java_thread_min_stack_allowed = 128 * K;
686 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
687
688 // return default stack size for thr_type
689 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
690 // default stack size (compiler thread needs larger stack)
691 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
692 return s;
693 }
694
695 #ifndef PRODUCT
696 void os::verify_stack_alignment() {
697 }
698 #endif
699
700 int os::extra_bang_size_in_bytes() {
701 // SPARC does not require the additional stack bang.
702 return 0;
703 }