1 /*
2 * Copyright (c) 1999, 2014, 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 "assembler_sparc.inline.hpp"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "jvm_linux.h"
34 #include "memory/allocation.inline.hpp"
35 #include "mutex_linux.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/timer.hpp"
52 #include "thread_linux.inline.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 static inline void set_cont_address(sigcontext* ctx, address addr) {
89 SIG_PC(ctx) = (intptr_t)addr;
90 SIG_NPC(ctx) = (intptr_t)(addr+4);
91 }
92
93 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
94 // currently interrupted by SIGPROF.
95 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested
96 // signal frames. Currently we don't do that on Linux, so it's the
97 // same as os::fetch_frame_from_context().
98 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
99 ucontext_t* uc,
100 intptr_t** ret_sp,
101 intptr_t** ret_fp) {
102 assert(thread != NULL, "just checking");
103 assert(ret_sp != NULL, "just checking");
104 assert(ret_fp != NULL, "just checking");
105
106 return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
107 }
108
109 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
110 intptr_t** ret_sp,
111 intptr_t** ret_fp) {
112 ucontext_t* uc = (ucontext_t*) ucVoid;
113 ExtendedPC epc;
114
115 if (uc != NULL) {
116 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
117 if (ret_sp) {
118 *ret_sp = os::Linux::ucontext_get_sp(uc);
119 }
120 if (ret_fp) {
121 *ret_fp = os::Linux::ucontext_get_fp(uc);
122 }
123 } else {
124 // construct empty ExtendedPC for return value checking
125 epc = ExtendedPC(NULL);
126 if (ret_sp) {
127 *ret_sp = (intptr_t*) NULL;
128 }
129 if (ret_fp) {
130 *ret_fp = (intptr_t*) NULL;
131 }
132 }
133
134 return epc;
135 }
136
137 frame os::fetch_frame_from_context(void* ucVoid) {
138 intptr_t* sp;
139 intptr_t* fp;
140 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
141 return frame(sp, fp, epc.pc());
142 }
143
144 frame os::get_sender_for_C_frame(frame* fr) {
145 return frame(fr->sender_sp(), frame::unpatchable, fr->sender_pc());
146 }
147
148 frame os::current_frame() {
149 intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
150 frame myframe(sp, frame::unpatchable,
151 CAST_FROM_FN_PTR(address, os::current_frame));
152 if (os::is_first_C_frame(&myframe)) {
153 // stack is not walkable
154 return frame(NULL, frame::unpatchable, NULL);
155 } else {
156 return os::get_sender_for_C_frame(&myframe);
157 }
158 }
159
160 address os::current_stack_pointer() {
161 register void *sp __asm__ ("sp");
162 return (address)sp;
163 }
164
165 static void current_stack_region(address* bottom, size_t* size) {
166 if (os::Linux::is_initial_thread()) {
167 // initial thread needs special handling because pthread_getattr_np()
168 // may return bogus value.
169 *bottom = os::Linux::initial_thread_stack_bottom();
170 *size = os::Linux::initial_thread_stack_size();
171 } else {
172 pthread_attr_t attr;
173
174 int rslt = pthread_getattr_np(pthread_self(), &attr);
175
176 // JVM needs to know exact stack location, abort if it fails
177 if (rslt != 0) {
178 if (rslt == ENOMEM) {
179 vm_exit_out_of_memory(0, "pthread_getattr_np");
180 } else {
181 fatal(err_msg("pthread_getattr_np failed with errno = %d", rslt));
182 }
183 }
184
185 if (pthread_attr_getstack(&attr, (void**)bottom, size) != 0) {
186 fatal("Can not locate current stack attributes!");
187 }
188
189 pthread_attr_destroy(&attr);
190 }
191 assert(os::current_stack_pointer() >= *bottom &&
192 os::current_stack_pointer() < *bottom + *size, "just checking");
193 }
194
195 address os::current_stack_base() {
196 address bottom;
197 size_t size;
198 current_stack_region(&bottom, &size);
199 return bottom + size;
200 }
201
202 size_t os::current_stack_size() {
203 // stack size includes normal stack and HotSpot guard pages
204 address bottom;
205 size_t size;
206 current_stack_region(&bottom, &size);
207 return size;
208 }
209
210 char* os::non_memory_address_word() {
211 // Must never look like an address returned by reserve_memory,
212 // even in its subfields (as defined by the CPU immediate fields,
213 // if the CPU splits constants across multiple instructions).
214 // On SPARC, 0 != %hi(any real address), because there is no
215 // allocation in the first 1Kb of the virtual address space.
216 return (char*) 0;
217 }
218
219 void os::initialize_thread(Thread* thr) {}
220
221 void os::print_context(outputStream *st, void *context) {
222 if (context == NULL) return;
223
224 ucontext_t* uc = (ucontext_t*)context;
225 sigcontext* sc = (sigcontext*)context;
226 st->print_cr("Registers:");
227
228 st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
229 " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
230 SIG_REGS(sc).u_regs[CON_G1],
231 SIG_REGS(sc).u_regs[CON_G2],
232 SIG_REGS(sc).u_regs[CON_G3],
233 SIG_REGS(sc).u_regs[CON_G4]);
234 st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
235 " G7=" INTPTR_FORMAT " Y=" INTPTR_FORMAT,
236 SIG_REGS(sc).u_regs[CON_G5],
237 SIG_REGS(sc).u_regs[CON_G6],
238 SIG_REGS(sc).u_regs[CON_G7],
239 SIG_REGS(sc).y);
240 st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
241 " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
242 SIG_REGS(sc).u_regs[CON_O0],
243 SIG_REGS(sc).u_regs[CON_O1],
244 SIG_REGS(sc).u_regs[CON_O2],
245 SIG_REGS(sc).u_regs[CON_O3]);
246 st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
247 " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
248 SIG_REGS(sc).u_regs[CON_O4],
249 SIG_REGS(sc).u_regs[CON_O5],
250 SIG_REGS(sc).u_regs[CON_O6],
251 SIG_REGS(sc).u_regs[CON_O7]);
252
253
254 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
255 st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
256 " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
257 sp[L0->sp_offset_in_saved_window()],
258 sp[L1->sp_offset_in_saved_window()],
259 sp[L2->sp_offset_in_saved_window()],
260 sp[L3->sp_offset_in_saved_window()]);
261 st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
262 " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
263 sp[L4->sp_offset_in_saved_window()],
264 sp[L5->sp_offset_in_saved_window()],
265 sp[L6->sp_offset_in_saved_window()],
266 sp[L7->sp_offset_in_saved_window()]);
267 st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
268 " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
269 sp[I0->sp_offset_in_saved_window()],
270 sp[I1->sp_offset_in_saved_window()],
271 sp[I2->sp_offset_in_saved_window()],
272 sp[I3->sp_offset_in_saved_window()]);
273 st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
274 " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
275 sp[I4->sp_offset_in_saved_window()],
276 sp[I5->sp_offset_in_saved_window()],
277 sp[I6->sp_offset_in_saved_window()],
278 sp[I7->sp_offset_in_saved_window()]);
279
280 st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
281 SIG_PC(sc),
282 SIG_NPC(sc));
283 st->cr();
284 st->cr();
285
286 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
287 print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
288 st->cr();
289
290 // Note: it may be unsafe to inspect memory near pc. For example, pc may
291 // point to garbage if entry point in an nmethod is corrupted. Leave
292 // this at the end, and hope for the best.
293 address pc = os::Linux::ucontext_get_pc(uc);
294 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
295 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
296 }
297
298
299 void os::print_register_info(outputStream *st, void *context) {
300 if (context == NULL) return;
301
302 ucontext_t *uc = (ucontext_t*)context;
303 sigcontext* sc = (sigcontext*)context;
304 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
305
306 st->print_cr("Register to memory mapping:");
307 st->cr();
308
309 // this is only for the "general purpose" registers
310 st->print("G1="); print_location(st, SIG_REGS(sc).u_regs[CON_G1]);
311 st->print("G2="); print_location(st, SIG_REGS(sc).u_regs[CON_G2]);
312 st->print("G3="); print_location(st, SIG_REGS(sc).u_regs[CON_G3]);
313 st->print("G4="); print_location(st, SIG_REGS(sc).u_regs[CON_G4]);
314 st->print("G5="); print_location(st, SIG_REGS(sc).u_regs[CON_G5]);
315 st->print("G6="); print_location(st, SIG_REGS(sc).u_regs[CON_G6]);
316 st->print("G7="); print_location(st, SIG_REGS(sc).u_regs[CON_G7]);
317 st->cr();
318
319 st->print("O0="); print_location(st, SIG_REGS(sc).u_regs[CON_O0]);
320 st->print("O1="); print_location(st, SIG_REGS(sc).u_regs[CON_O1]);
321 st->print("O2="); print_location(st, SIG_REGS(sc).u_regs[CON_O2]);
322 st->print("O3="); print_location(st, SIG_REGS(sc).u_regs[CON_O3]);
323 st->print("O4="); print_location(st, SIG_REGS(sc).u_regs[CON_O4]);
324 st->print("O5="); print_location(st, SIG_REGS(sc).u_regs[CON_O5]);
325 st->print("O6="); print_location(st, SIG_REGS(sc).u_regs[CON_O6]);
326 st->print("O7="); print_location(st, SIG_REGS(sc).u_regs[CON_O7]);
327 st->cr();
328
329 st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
330 st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
331 st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
332 st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
333 st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
334 st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
335 st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
336 st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
337 st->cr();
338
339 st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
340 st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
341 st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
342 st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
343 st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
344 st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
345 st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
346 st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
347 st->cr();
348 }
349
350
351 address os::Linux::ucontext_get_pc(ucontext_t* uc) {
352 return (address) SIG_PC((sigcontext*)uc);
353 }
354
355 intptr_t* os::Linux::ucontext_get_sp(ucontext_t *uc) {
356 return (intptr_t*)
357 ((intptr_t)SIG_REGS((sigcontext*)uc).u_regs[CON_O6] + STACK_BIAS);
358 }
359
360 // not used on Sparc
361 intptr_t* os::Linux::ucontext_get_fp(ucontext_t *uc) {
362 ShouldNotReachHere();
363 return NULL;
364 }
365
366 // Utility functions
367
368 extern "C" void Fetch32PFI();
369 extern "C" void Fetch32Resume();
370 extern "C" void FetchNPFI();
371 extern "C" void FetchNResume();
372
373 inline static bool checkPrefetch(sigcontext* uc, address pc) {
374 if (pc == (address) Fetch32PFI) {
375 set_cont_address(uc, address(Fetch32Resume));
376 return true;
377 }
378 if (pc == (address) FetchNPFI) {
379 set_cont_address(uc, address(FetchNResume));
380 return true;
381 }
382 return false;
383 }
384
385 inline static bool checkOverflow(sigcontext* uc,
386 address pc,
387 address addr,
388 JavaThread* thread,
389 address* stub) {
390 // check if fault address is within thread stack
391 if (addr < thread->stack_base() &&
392 addr >= thread->stack_base() - thread->stack_size()) {
393 // stack overflow
394 if (thread->in_stack_yellow_zone(addr)) {
395 thread->disable_stack_yellow_zone();
396 if (thread->thread_state() == _thread_in_Java) {
397 // Throw a stack overflow exception. Guard pages will be reenabled
398 // while unwinding the stack.
399 *stub =
400 SharedRuntime::continuation_for_implicit_exception(thread,
401 pc,
402 SharedRuntime::STACK_OVERFLOW);
403 } else {
404 // Thread was in the vm or native code. Return and try to finish.
405 return true;
406 }
407 } else if (thread->in_stack_red_zone(addr)) {
408 // Fatal red zone violation. Disable the guard pages and fall through
409 // to handle_unexpected_exception way down below.
410 thread->disable_stack_red_zone();
411 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
412
413 // This is a likely cause, but hard to verify. Let's just print
414 // it as a hint.
415 tty->print_raw_cr("Please check if any of your loaded .so files has "
416 "enabled executable stack (see man page execstack(8))");
417 } else {
418 // Accessing stack address below sp may cause SEGV if current
419 // thread has MAP_GROWSDOWN stack. This should only happen when
420 // current thread was created by user code with MAP_GROWSDOWN flag
421 // and then attached to VM. See notes in os_linux.cpp.
422 if (thread->osthread()->expanding_stack() == 0) {
423 thread->osthread()->set_expanding_stack();
424 if (os::Linux::manually_expand_stack(thread, addr)) {
425 thread->osthread()->clear_expanding_stack();
426 return true;
427 }
428 thread->osthread()->clear_expanding_stack();
429 } else {
430 fatal("recursive segv. expanding stack.");
431 }
432 }
433 }
434 return false;
435 }
436
437 inline static bool checkPollingPage(address pc, address fault, address* stub) {
438 if (fault == os::get_polling_page()) {
439 *stub = SharedRuntime::get_poll_stub(pc);
440 return true;
441 }
442 return false;
443 }
444
445 inline static bool checkByteBuffer(address pc, address* stub) {
446 // BugId 4454115: A read from a MappedByteBuffer can fault
447 // here if the underlying file has been truncated.
448 // Do not crash the VM in such a case.
449 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
450 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
451 if (nm != NULL && nm->has_unsafe_access()) {
452 *stub = StubRoutines::handler_for_unsafe_access();
453 return true;
454 }
455 return false;
456 }
457
458 inline static bool checkVerifyOops(address pc, address fault, address* stub) {
459 if (pc >= MacroAssembler::_verify_oop_implicit_branch[0]
460 && pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
461 *stub = MacroAssembler::_verify_oop_implicit_branch[2];
462 warning("fixed up memory fault in +VerifyOops at address "
463 INTPTR_FORMAT, fault);
464 return true;
465 }
466 return false;
467 }
468
469 inline static bool checkFPFault(address pc, int code,
470 JavaThread* thread, address* stub) {
471 if (code == FPE_INTDIV || code == FPE_FLTDIV) {
472 *stub =
473 SharedRuntime::
474 continuation_for_implicit_exception(thread,
475 pc,
476 SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
477 return true;
478 }
479 return false;
480 }
481
482 inline static bool checkNullPointer(address pc, intptr_t fault,
483 JavaThread* thread, address* stub) {
484 if (!MacroAssembler::needs_explicit_null_check(fault)) {
485 // Determination of interpreter/vtable stub/compiled code null
486 // exception
487 *stub =
488 SharedRuntime::
489 continuation_for_implicit_exception(thread, pc,
490 SharedRuntime::IMPLICIT_NULL);
491 return true;
492 }
493 return false;
494 }
495
496 inline static bool checkFastJNIAccess(address pc, address* stub) {
497 address addr = JNI_FastGetField::find_slowcase_pc(pc);
498 if (addr != (address)-1) {
499 *stub = addr;
500 return true;
501 }
502 return false;
503 }
504
505 inline static bool checkSerializePage(JavaThread* thread, address addr) {
506 return os::is_memory_serialize_page(thread, addr);
507 }
508
509 inline static bool checkZombie(sigcontext* uc, address* pc, address* stub) {
510 if (nativeInstruction_at(*pc)->is_zombie()) {
511 // zombie method (ld [%g0],%o7 instruction)
512 *stub = SharedRuntime::get_handle_wrong_method_stub();
513
514 // At the stub it needs to look like a call from the caller of this
515 // method (not a call from the segv site).
516 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
517 return true;
518 }
519 return false;
520 }
521
522 inline static bool checkICMiss(sigcontext* uc, address* pc, address* stub) {
523 #ifdef COMPILER2
524 if (nativeInstruction_at(*pc)->is_ic_miss_trap()) {
525 #ifdef ASSERT
526 #ifdef TIERED
527 CodeBlob* cb = CodeCache::find_blob_unsafe(*pc);
528 assert(cb->is_compiled_by_c2(), "Wrong compiler");
529 #endif // TIERED
530 #endif // ASSERT
531 // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
532 *stub = SharedRuntime::get_ic_miss_stub();
533 // At the stub it needs to look like a call from the caller of this
534 // method (not a call from the segv site).
535 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
536 return true;
537 }
538 #endif // COMPILER2
539 return false;
540 }
541
542 extern "C" JNIEXPORT int
543 JVM_handle_linux_signal(int sig,
544 siginfo_t* info,
545 void* ucVoid,
546 int abort_if_unrecognized) {
547 // in fact this isn't ucontext_t* at all, but struct sigcontext*
548 // but Linux porting layer uses ucontext_t, so to minimize code change
549 // we cast as needed
550 ucontext_t* ucFake = (ucontext_t*) ucVoid;
551 sigcontext* uc = (sigcontext*)ucVoid;
552
553 Thread* t = ThreadLocalStorage::get_thread_slow();
554
555 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
556 // (no destructors can be run)
557 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
558
559 SignalHandlerMark shm(t);
560
561 // Note: it's not uncommon that JNI code uses signal/sigset to install
562 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
563 // or have a SIGILL handler when detecting CPU type). When that happens,
564 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
565 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
566 // that do not require siginfo/ucontext first.
567
568 if (sig == SIGPIPE || sig == SIGXFSZ) {
569 // allow chained handler to go first
570 if (os::Linux::chained_handler(sig, info, ucVoid)) {
571 return true;
572 } else {
573 if (PrintMiscellaneous && (WizardMode || Verbose)) {
574 char buf[64];
575 warning("Ignoring %s - see bugs 4229104 or 646499219",
576 os::exception_name(sig, buf, sizeof(buf)));
577 }
578 return true;
579 }
580 }
581
582 JavaThread* thread = NULL;
583 VMThread* vmthread = NULL;
584 if (os::Linux::signal_handlers_are_installed) {
585 if (t != NULL ){
586 if(t->is_Java_thread()) {
587 thread = (JavaThread*)t;
588 }
589 else if(t->is_VM_thread()){
590 vmthread = (VMThread *)t;
591 }
592 }
593 }
594
595 // decide if this trap can be handled by a stub
596 address stub = NULL;
597 address pc = NULL;
598 address npc = NULL;
599
600 //%note os_trap_1
601 if (info != NULL && uc != NULL && thread != NULL) {
602 pc = address(SIG_PC(uc));
603 npc = address(SIG_NPC(uc));
604
605 // Check to see if we caught the safepoint code in the
606 // process of write protecting the memory serialization page.
607 // It write enables the page immediately after protecting it
608 // so we can just return to retry the write.
609 if ((sig == SIGSEGV) && checkSerializePage(thread, (address)info->si_addr)) {
610 // Block current thread until the memory serialize page permission restored.
611 os::block_on_serialize_page_trap();
612 return 1;
613 }
614
615 if (checkPrefetch(uc, pc)) {
616 return 1;
617 }
618
619 // Handle ALL stack overflow variations here
620 if (sig == SIGSEGV) {
621 if (checkOverflow(uc, pc, (address)info->si_addr, thread, &stub)) {
622 return 1;
623 }
624 }
625
626 if (sig == SIGBUS &&
627 thread->thread_state() == _thread_in_vm &&
628 thread->doing_unsafe_access()) {
629 stub = StubRoutines::handler_for_unsafe_access();
630 }
631
632 if (thread->thread_state() == _thread_in_Java) {
633 do {
634 // Java thread running in Java code => find exception handler if any
635 // a fault inside compiled code, the interpreter, or a stub
636
637 if ((sig == SIGSEGV) && checkPollingPage(pc, (address)info->si_addr, &stub)) {
638 break;
639 }
640
641 if ((sig == SIGBUS) && checkByteBuffer(pc, &stub)) {
642 break;
643 }
644
645 if ((sig == SIGSEGV || sig == SIGBUS) &&
646 checkVerifyOops(pc, (address)info->si_addr, &stub)) {
647 break;
648 }
649
650 if ((sig == SIGSEGV) && checkZombie(uc, &pc, &stub)) {
651 break;
652 }
653
654 if ((sig == SIGILL) && checkICMiss(uc, &pc, &stub)) {
655 break;
656 }
657
658 if ((sig == SIGFPE) && checkFPFault(pc, info->si_code, thread, &stub)) {
659 break;
660 }
661
662 if ((sig == SIGSEGV) &&
663 checkNullPointer(pc, (intptr_t)info->si_addr, thread, &stub)) {
664 break;
665 }
666 } while (0);
667
668 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
669 // and the heap gets shrunk before the field access.
670 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
671 checkFastJNIAccess(pc, &stub);
672 }
673 }
674
675 if (stub != NULL) {
676 // save all thread context in case we need to restore it
677 thread->set_saved_exception_pc(pc);
678 thread->set_saved_exception_npc(npc);
679 set_cont_address(uc, stub);
680 return true;
681 }
682 }
683
684 // signal-chaining
685 if (os::Linux::chained_handler(sig, info, ucVoid)) {
686 return true;
687 }
688
689 if (!abort_if_unrecognized) {
690 // caller wants another chance, so give it to him
691 return false;
692 }
693
694 if (pc == NULL && uc != NULL) {
695 pc = os::Linux::ucontext_get_pc((ucontext_t*)uc);
696 }
697
698 // unmask current signal
699 sigset_t newset;
700 sigemptyset(&newset);
701 sigaddset(&newset, sig);
702 sigprocmask(SIG_UNBLOCK, &newset, NULL);
703
704 VMError err(t, sig, pc, info, ucVoid);
705 err.report_and_die();
706
707 ShouldNotReachHere();
708 }
709
710 void os::Linux::init_thread_fpu_state(void) {
711 // Nothing to do
712 }
713
714 int os::Linux::get_fpu_control_word() {
715 return 0;
716 }
717
718 void os::Linux::set_fpu_control_word(int fpu) {
719 // nothing
720 }
721
722 bool os::is_allocatable(size_t bytes) {
723 #ifdef _LP64
724 return true;
725 #else
726 if (bytes < 2 * G) {
727 return true;
728 }
729
730 char* addr = reserve_memory(bytes, NULL);
731
732 if (addr != NULL) {
733 release_memory(addr, bytes);
734 }
735
736 return addr != NULL;
737 #endif // _LP64
738 }
739
740 ///////////////////////////////////////////////////////////////////////////////
741 // thread stack
742
743 size_t os::Linux::min_stack_allowed = 128 * K;
744
745 // pthread on Ubuntu is always in floating stack mode
746 bool os::Linux::supports_variable_stack_size() { return true; }
747
748 // return default stack size for thr_type
749 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
750 // default stack size (compiler thread needs larger stack)
751 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
752 return s;
753 }
754
755 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
756 // Creating guard page is very expensive. Java thread has HotSpot
757 // guard page, only enable glibc guard page for non-Java threads.
758 return (thr_type == java_thread ? 0 : page_size());
759 }
760
761 #ifndef PRODUCT
762 void os::verify_stack_alignment() {
763 }
764 #endif