1 /*
2 * Copyright (c) 1999, 2011, 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 #ifdef COMPILER1
56 #include "c1/c1_Runtime1.hpp"
57 #endif
58 #ifdef COMPILER2
59 #include "opto/runtime.hpp"
60 #endif
61
62
63 // Linux/Sparc has rather obscure naming of registers in sigcontext
64 // different between 32 and 64 bits
65 #ifdef _LP64
66 #define SIG_PC(x) ((x)->sigc_regs.tpc)
67 #define SIG_NPC(x) ((x)->sigc_regs.tnpc)
68 #define SIG_REGS(x) ((x)->sigc_regs)
69 #else
70 #define SIG_PC(x) ((x)->si_regs.pc)
71 #define SIG_NPC(x) ((x)->si_regs.npc)
72 #define SIG_REGS(x) ((x)->si_regs)
73 #endif
74
75 // those are to reference registers in sigcontext
76 enum {
77 CON_G0 = 0,
78 CON_G1,
79 CON_G2,
80 CON_G3,
81 CON_G4,
82 CON_G5,
83 CON_G6,
84 CON_G7,
85 CON_O0,
86 CON_O1,
87 CON_O2,
88 CON_O3,
89 CON_O4,
90 CON_O5,
91 CON_O6,
92 CON_O7,
93 };
94
95 static inline void set_cont_address(sigcontext* ctx, address addr) {
96 SIG_PC(ctx) = (intptr_t)addr;
97 SIG_NPC(ctx) = (intptr_t)(addr+4);
98 }
99
100 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
101 // currently interrupted by SIGPROF.
102 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested
103 // signal frames. Currently we don't do that on Linux, so it's the
104 // same as os::fetch_frame_from_context().
105 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
106 ucontext_t* uc,
107 intptr_t** ret_sp,
108 intptr_t** ret_fp) {
109 assert(thread != NULL, "just checking");
110 assert(ret_sp != NULL, "just checking");
111 assert(ret_fp != NULL, "just checking");
112
113 return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
114 }
115
116 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
117 intptr_t** ret_sp,
118 intptr_t** ret_fp) {
119 ucontext_t* uc = (ucontext_t*) ucVoid;
120 ExtendedPC epc;
121
122 if (uc != NULL) {
123 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
124 if (ret_sp) {
125 *ret_sp = os::Linux::ucontext_get_sp(uc);
126 }
127 if (ret_fp) {
128 *ret_fp = os::Linux::ucontext_get_fp(uc);
129 }
130 } else {
131 // construct empty ExtendedPC for return value checking
132 epc = ExtendedPC(NULL);
133 if (ret_sp) {
134 *ret_sp = (intptr_t*) NULL;
135 }
136 if (ret_fp) {
137 *ret_fp = (intptr_t*) NULL;
138 }
139 }
140
141 return epc;
142 }
143
144 frame os::fetch_frame_from_context(void* ucVoid) {
145 intptr_t* sp;
146 intptr_t* fp;
147 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
148 return frame(sp, fp, epc.pc());
149 }
150
151 frame os::get_sender_for_C_frame(frame* fr) {
152 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
153 }
154
155 frame os::current_frame() {
156 fprintf(stderr, "current_frame()");
157
158 intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
159 frame myframe(sp, frame::unpatchable,
160 CAST_FROM_FN_PTR(address, os::current_frame));
161 if (os::is_first_C_frame(&myframe)) {
162 // stack is not walkable
163 return frame(NULL, frame::unpatchable, NULL);
164 } else {
165 return os::get_sender_for_C_frame(&myframe);
166 }
167 }
168
169 address os::current_stack_pointer() {
170 register void *sp __asm__ ("sp");
171 return (address)sp;
172 }
173
174 static void current_stack_region(address* bottom, size_t* size) {
175 if (os::Linux::is_initial_thread()) {
176 // initial thread needs special handling because pthread_getattr_np()
177 // may return bogus value.
178 *bottom = os::Linux::initial_thread_stack_bottom();
179 *size = os::Linux::initial_thread_stack_size();
180 } else {
181 pthread_attr_t attr;
182
183 int rslt = pthread_getattr_np(pthread_self(), &attr);
184
185 // JVM needs to know exact stack location, abort if it fails
186 if (rslt != 0) {
187 if (rslt == ENOMEM) {
188 vm_exit_out_of_memory(0, "pthread_getattr_np");
189 } else {
190 fatal(err_msg("pthread_getattr_np failed with errno = %d", rslt));
191 }
192 }
193
194 if (pthread_attr_getstack(&attr, (void**)bottom, size) != 0) {
195 fatal("Can not locate current stack attributes!");
196 }
197
198 pthread_attr_destroy(&attr);
199 }
200 assert(os::current_stack_pointer() >= *bottom &&
201 os::current_stack_pointer() < *bottom + *size, "just checking");
202 }
203
204 address os::current_stack_base() {
205 address bottom;
206 size_t size;
207 current_stack_region(&bottom, &size);
208 return bottom + size;
209 }
210
211 size_t os::current_stack_size() {
212 // stack size includes normal stack and HotSpot guard pages
213 address bottom;
214 size_t size;
215 current_stack_region(&bottom, &size);
216 return size;
217 }
218
219 char* os::non_memory_address_word() {
220 // Must never look like an address returned by reserve_memory,
221 // even in its subfields (as defined by the CPU immediate fields,
222 // if the CPU splits constants across multiple instructions).
223 // On SPARC, 0 != %hi(any real address), because there is no
224 // allocation in the first 1Kb of the virtual address space.
225 return (char*) 0;
226 }
227
228 void os::initialize_thread() {}
229
230 void os::print_context(outputStream *st, void *context) {
231 if (context == NULL) return;
232
233 ucontext_t* uc = (ucontext_t*)context;
234 sigcontext* sc = (sigcontext*)context;
235 st->print_cr("Registers:");
236
237 st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
238 " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
239 SIG_REGS(sc).u_regs[CON_G1],
240 SIG_REGS(sc).u_regs[CON_G2],
241 SIG_REGS(sc).u_regs[CON_G3],
242 SIG_REGS(sc).u_regs[CON_G4]);
243 st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
244 " G7=" INTPTR_FORMAT " Y=" INTPTR_FORMAT,
245 SIG_REGS(sc).u_regs[CON_G5],
246 SIG_REGS(sc).u_regs[CON_G6],
247 SIG_REGS(sc).u_regs[CON_G7],
248 SIG_REGS(sc).y);
249 st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
250 " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
251 SIG_REGS(sc).u_regs[CON_O0],
252 SIG_REGS(sc).u_regs[CON_O1],
253 SIG_REGS(sc).u_regs[CON_O2],
254 SIG_REGS(sc).u_regs[CON_O3]);
255 st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
256 " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
257 SIG_REGS(sc).u_regs[CON_O4],
258 SIG_REGS(sc).u_regs[CON_O5],
259 SIG_REGS(sc).u_regs[CON_O6],
260 SIG_REGS(sc).u_regs[CON_O7]);
261
262
263 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
264 st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
265 " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
266 sp[L0->sp_offset_in_saved_window()],
267 sp[L1->sp_offset_in_saved_window()],
268 sp[L2->sp_offset_in_saved_window()],
269 sp[L3->sp_offset_in_saved_window()]);
270 st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
271 " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
272 sp[L4->sp_offset_in_saved_window()],
273 sp[L5->sp_offset_in_saved_window()],
274 sp[L6->sp_offset_in_saved_window()],
275 sp[L7->sp_offset_in_saved_window()]);
276 st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
277 " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
278 sp[I0->sp_offset_in_saved_window()],
279 sp[I1->sp_offset_in_saved_window()],
280 sp[I2->sp_offset_in_saved_window()],
281 sp[I3->sp_offset_in_saved_window()]);
282 st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
283 " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
284 sp[I4->sp_offset_in_saved_window()],
285 sp[I5->sp_offset_in_saved_window()],
286 sp[I6->sp_offset_in_saved_window()],
287 sp[I7->sp_offset_in_saved_window()]);
288
289 st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
290 SIG_PC(sc),
291 SIG_NPC(sc));
292 st->cr();
293 st->cr();
294
295 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
296 print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
297 st->cr();
298
299 // Note: it may be unsafe to inspect memory near pc. For example, pc may
300 // point to garbage if entry point in an nmethod is corrupted. Leave
301 // this at the end, and hope for the best.
302 address pc = os::Linux::ucontext_get_pc(uc);
303 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
304 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
305 }
306
307
308 void os::print_register_info(outputStream *st, void *context) {
309 if (context == NULL) return;
310
311 ucontext_t *uc = (ucontext_t*)context;
312 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
313
314 st->print_cr("Register to memory mapping:");
315 st->cr();
316
317 // this is only for the "general purpose" registers
318 st->print("G1="); print_location(st, SIG_REGS(sc).u_regs[CON__G1]);
319 st->print("G2="); print_location(st, SIG_REGS(sc).u_regs[CON__G2]);
320 st->print("G3="); print_location(st, SIG_REGS(sc).u_regs[CON__G3]);
321 st->print("G4="); print_location(st, SIG_REGS(sc).u_regs[CON__G4]);
322 st->print("G5="); print_location(st, SIG_REGS(sc).u_regs[CON__G5]);
323 st->print("G6="); print_location(st, SIG_REGS(sc).u_regs[CON__G6]);
324 st->print("G7="); print_location(st, SIG_REGS(sc).u_regs[CON__G7]);
325 st->cr();
326
327 st->print("O0="); print_location(st, SIG_REGS(sc).u_regs[CON__O0]);
328 st->print("O1="); print_location(st, SIG_REGS(sc).u_regs[CON__O1]);
329 st->print("O2="); print_location(st, SIG_REGS(sc).u_regs[CON__O2]);
330 st->print("O3="); print_location(st, SIG_REGS(sc).u_regs[CON__O3]);
331 st->print("O4="); print_location(st, SIG_REGS(sc).u_regs[CON__O4]);
332 st->print("O5="); print_location(st, SIG_REGS(sc).u_regs[CON__O5]);
333 st->print("O6="); print_location(st, SIG_REGS(sc).u_regs[CON__O6]);
334 st->print("O7="); print_location(st, SIG_REGS(sc).u_regs[CON__O7]);
335 st->cr();
336
337 st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
338 st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
339 st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
340 st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
341 st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
342 st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
343 st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
344 st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
345 st->cr();
346
347 st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
348 st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
349 st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
350 st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
351 st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
352 st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
353 st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
354 st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
355 st->cr();
356 }
357
358
359 address os::Linux::ucontext_get_pc(ucontext_t* uc) {
360 return (address) SIG_PC((sigcontext*)uc);
361 }
362
363 intptr_t* os::Linux::ucontext_get_sp(ucontext_t *uc) {
364 return (intptr_t*)
365 ((intptr_t)SIG_REGS((sigcontext*)uc).u_regs[CON_O6] + STACK_BIAS);
366 }
367
368 // not used on Sparc
369 intptr_t* os::Linux::ucontext_get_fp(ucontext_t *uc) {
370 ShouldNotReachHere();
371 return NULL;
372 }
373
374 // Utility functions
375
376 extern "C" void Fetch32PFI();
377 extern "C" void Fetch32Resume();
378 extern "C" void FetchNPFI();
379 extern "C" void FetchNResume();
380
381 inline static bool checkPrefetch(sigcontext* uc, address pc) {
382 if (pc == (address) Fetch32PFI) {
383 set_cont_address(uc, address(Fetch32Resume));
384 return true;
385 }
386 if (pc == (address) FetchNPFI) {
387 set_cont_address(uc, address(FetchNResume));
388 return true;
389 }
390 return false;
391 }
392
393 inline static bool checkOverflow(sigcontext* uc,
394 address pc,
395 address addr,
396 JavaThread* thread,
397 address* stub) {
398 // check if fault address is within thread stack
399 if (addr < thread->stack_base() &&
400 addr >= thread->stack_base() - thread->stack_size()) {
401 // stack overflow
402 if (thread->in_stack_yellow_zone(addr)) {
403 thread->disable_stack_yellow_zone();
404 if (thread->thread_state() == _thread_in_Java) {
405 // Throw a stack overflow exception. Guard pages will be reenabled
406 // while unwinding the stack.
407 *stub =
408 SharedRuntime::continuation_for_implicit_exception(thread,
409 pc,
410 SharedRuntime::STACK_OVERFLOW);
411 } else {
412 // Thread was in the vm or native code. Return and try to finish.
413 return true;
414 }
415 } else if (thread->in_stack_red_zone(addr)) {
416 // Fatal red zone violation. Disable the guard pages and fall through
417 // to handle_unexpected_exception way down below.
418 thread->disable_stack_red_zone();
419 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
420 } else {
421 // Accessing stack address below sp may cause SEGV if current
422 // thread has MAP_GROWSDOWN stack. This should only happen when
423 // current thread was created by user code with MAP_GROWSDOWN flag
424 // and then attached to VM. See notes in os_linux.cpp.
425 if (thread->osthread()->expanding_stack() == 0) {
426 thread->osthread()->set_expanding_stack();
427 if (os::Linux::manually_expand_stack(thread, addr)) {
428 thread->osthread()->clear_expanding_stack();
429 return true;
430 }
431 thread->osthread()->clear_expanding_stack();
432 } else {
433 fatal("recursive segv. expanding stack.");
434 }
435 }
436 }
437 return false;
438 }
439
440 inline static bool checkPollingPage(address pc, address fault, address* stub) {
441 if (fault == os::get_polling_page()) {
442 *stub = SharedRuntime::get_poll_stub(pc);
443 return true;
444 }
445 return false;
446 }
447
448 inline static bool checkByteBuffer(address pc, address* stub) {
449 // BugId 4454115: A read from a MappedByteBuffer can fault
450 // here if the underlying file has been truncated.
451 // Do not crash the VM in such a case.
452 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
453 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
454 if (nm != NULL && nm->has_unsafe_access()) {
455 *stub = StubRoutines::handler_for_unsafe_access();
456 return true;
457 }
458 return false;
459 }
460
461 inline static bool checkVerifyOops(address pc, address fault, address* stub) {
462 if (pc >= MacroAssembler::_verify_oop_implicit_branch[0]
463 && pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
464 *stub = MacroAssembler::_verify_oop_implicit_branch[2];
465 warning("fixed up memory fault in +VerifyOops at address "
466 INTPTR_FORMAT, fault);
467 return true;
468 }
469 return false;
470 }
471
472 inline static bool checkFPFault(address pc, int code,
473 JavaThread* thread, address* stub) {
474 if (code == FPE_INTDIV || code == FPE_FLTDIV) {
475 *stub =
476 SharedRuntime::
477 continuation_for_implicit_exception(thread,
478 pc,
479 SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
480 return true;
481 }
482 return false;
483 }
484
485 inline static bool checkNullPointer(address pc, intptr_t fault,
486 JavaThread* thread, address* stub) {
487 if (!MacroAssembler::needs_explicit_null_check(fault)) {
488 // Determination of interpreter/vtable stub/compiled code null
489 // exception
490 *stub =
491 SharedRuntime::
492 continuation_for_implicit_exception(thread, pc,
493 SharedRuntime::IMPLICIT_NULL);
494 return true;
495 }
496 return false;
497 }
498
499 inline static bool checkFastJNIAccess(address pc, address* stub) {
500 address addr = JNI_FastGetField::find_slowcase_pc(pc);
501 if (addr != (address)-1) {
502 *stub = addr;
503 return true;
504 }
505 return false;
506 }
507
508 inline static bool checkSerializePage(JavaThread* thread, address addr) {
509 return os::is_memory_serialize_page(thread, addr);
510 }
511
512 inline static bool checkZombie(sigcontext* uc, address* pc, address* stub) {
513 if (nativeInstruction_at(*pc)->is_zombie()) {
514 // zombie method (ld [%g0],%o7 instruction)
515 *stub = SharedRuntime::get_handle_wrong_method_stub();
516
517 // At the stub it needs to look like a call from the caller of this
518 // method (not a call from the segv site).
519 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
520 return true;
521 }
522 return false;
523 }
524
525 inline static bool checkICMiss(sigcontext* uc, address* pc, address* stub) {
526 #ifdef COMPILER2
527 if (nativeInstruction_at(*pc)->is_ic_miss_trap()) {
528 #ifdef ASSERT
529 #ifdef TIERED
530 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
531 assert(cb->is_compiled_by_c2(), "Wrong compiler");
532 #endif // TIERED
533 #endif // ASSERT
534 // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
535 *stub = SharedRuntime::get_ic_miss_stub();
536 // At the stub it needs to look like a call from the caller of this
537 // method (not a call from the segv site).
538 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
539 return true;
540 }
541 #endif // COMPILER2
542 return false;
543 }
544
545 extern "C" JNIEXPORT int
546 JVM_handle_linux_signal(int sig,
547 siginfo_t* info,
548 void* ucVoid,
549 int abort_if_unrecognized) {
550 // in fact this isn't ucontext_t* at all, but struct sigcontext*
551 // but Linux porting layer uses ucontext_t, so to minimize code change
552 // we cast as needed
553 ucontext_t* ucFake = (ucontext_t*) ucVoid;
554 sigcontext* uc = (sigcontext*)ucVoid;
555
556 Thread* t = ThreadLocalStorage::get_thread_slow();
557
558 SignalHandlerMark shm(t);
559
560 // Note: it's not uncommon that JNI code uses signal/sigset to install
561 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
562 // or have a SIGILL handler when detecting CPU type). When that happens,
563 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
564 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
565 // that do not require siginfo/ucontext first.
566
567 if (sig == SIGPIPE || sig == SIGXFSZ) {
568 // allow chained handler to go first
569 if (os::Linux::chained_handler(sig, info, ucVoid)) {
570 return true;
571 } else {
572 if (PrintMiscellaneous && (WizardMode || Verbose)) {
573 char buf[64];
574 warning("Ignoring %s - see bugs 4229104 or 646499219",
575 os::exception_name(sig, buf, sizeof(buf)));
576 }
577 return true;
578 }
579 }
580
581 JavaThread* thread = NULL;
582 VMThread* vmthread = NULL;
583 if (os::Linux::signal_handlers_are_installed) {
584 if (t != NULL ){
585 if(t->is_Java_thread()) {
586 thread = (JavaThread*)t;
587 }
588 else if(t->is_VM_thread()){
589 vmthread = (VMThread *)t;
590 }
591 }
592 }
593
594 // decide if this trap can be handled by a stub
595 address stub = NULL;
596 address pc = NULL;
597 address npc = NULL;
598
599 //%note os_trap_1
600 if (info != NULL && uc != NULL && thread != NULL) {
601 pc = address(SIG_PC(uc));
602 npc = address(SIG_NPC(uc));
603
604 // Check to see if we caught the safepoint code in the
605 // process of write protecting the memory serialization page.
606 // It write enables the page immediately after protecting it
607 // so we can just return to retry the write.
608 if ((sig == SIGSEGV) && checkSerializePage(thread, (address)info->si_addr)) {
609 // Block current thread until the memory serialize page permission restored.
610 os::block_on_serialize_page_trap();
611 return 1;
612 }
613
614 if (checkPrefetch(uc, pc)) {
615 return 1;
616 }
617
618 // Handle ALL stack overflow variations here
619 if (sig == SIGSEGV) {
620 if (checkOverflow(uc, pc, (address)info->si_addr, thread, &stub)) {
621 return 1;
622 }
623 }
624
625 if (sig == SIGBUS &&
626 thread->thread_state() == _thread_in_vm &&
627 thread->doing_unsafe_access()) {
628 stub = StubRoutines::handler_for_unsafe_access();
629 }
630
631 if (thread->thread_state() == _thread_in_Java) {
632 do {
633 // Java thread running in Java code => find exception handler if any
634 // a fault inside compiled code, the interpreter, or a stub
635
636 if ((sig == SIGSEGV) && checkPollingPage(pc, (address)info->si_addr, &stub)) {
637 break;
638 }
639
640 if ((sig == SIGBUS) && checkByteBuffer(pc, &stub)) {
641 break;
642 }
643
644 if ((sig == SIGSEGV || sig == SIGBUS) &&
645 checkVerifyOops(pc, (address)info->si_addr, &stub)) {
646 break;
647 }
648
649 if ((sig == SIGSEGV) && checkZombie(uc, &pc, &stub)) {
650 break;
651 }
652
653 if ((sig == SIGILL) && checkICMiss(uc, &pc, &stub)) {
654 break;
655 }
656
657 if ((sig == SIGFPE) && checkFPFault(pc, info->si_code, thread, &stub)) {
658 break;
659 }
660
661 if ((sig == SIGSEGV) &&
662 checkNullPointer(pc, (intptr_t)info->si_addr, thread, &stub)) {
663 break;
664 }
665 } while (0);
666
667 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
668 // and the heap gets shrunk before the field access.
669 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
670 checkFastJNIAccess(pc, &stub);
671 }
672 }
673
674 if (stub != NULL) {
675 // save all thread context in case we need to restore it
676 thread->set_saved_exception_pc(pc);
677 thread->set_saved_exception_npc(npc);
678 set_cont_address(uc, stub);
679 return true;
680 }
681 }
682
683 // signal-chaining
684 if (os::Linux::chained_handler(sig, info, ucVoid)) {
685 return true;
686 }
687
688 if (!abort_if_unrecognized) {
689 // caller wants another chance, so give it to him
690 return false;
691 }
692
693 if (pc == NULL && uc != NULL) {
694 pc = os::Linux::ucontext_get_pc((ucontext_t*)uc);
695 }
696
697 // unmask current signal
698 sigset_t newset;
699 sigemptyset(&newset);
700 sigaddset(&newset, sig);
701 sigprocmask(SIG_UNBLOCK, &newset, NULL);
702
703 VMError err(t, sig, pc, info, ucVoid);
704 err.report_and_die();
705
706 ShouldNotReachHere();
707 }
708
709 void os::Linux::init_thread_fpu_state(void) {
710 // Nothing to do
711 }
712
713 int os::Linux::get_fpu_control_word() {
714 return 0;
715 }
716
717 void os::Linux::set_fpu_control_word(int fpu) {
718 // nothing
719 }
720
721 bool os::is_allocatable(size_t bytes) {
722 #ifdef _LP64
723 return true;
724 #else
725 if (bytes < 2 * G) {
726 return true;
727 }
728
729 char* addr = reserve_memory(bytes, NULL);
730
731 if (addr != NULL) {
732 release_memory(addr, bytes);
733 }
734
735 return addr != NULL;
736 #endif // _LP64
737 }
738
739 ///////////////////////////////////////////////////////////////////////////////
740 // thread stack
741
742 size_t os::Linux::min_stack_allowed = 128 * K;
743
744 // pthread on Ubuntu is always in floating stack mode
745 bool os::Linux::supports_variable_stack_size() { return true; }
746
747 // return default stack size for thr_type
748 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
749 // default stack size (compiler thread needs larger stack)
750 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
751 return s;
752 }
753
754 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
755 // Creating guard page is very expensive. Java thread has HotSpot
756 // guard page, only enable glibc guard page for non-Java threads.
757 return (thr_type == java_thread ? 0 : page_size());
758 }
759
760 #ifndef PRODUCT
761 void os::verify_stack_alignment() {
762 }
763 #endif