1 /*
2 * Copyright (c) 1999, 2017, 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 "classfile/classLoader.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "code/codeCache.hpp"
32 #include "code/icBuffer.hpp"
33 #include "code/vtableStubs.hpp"
34 #include "interpreter/interpreter.hpp"
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_misc.hpp"
40 #include "runtime/arguments.hpp"
41 #include "runtime/extendedPC.hpp"
42 #include "runtime/frame.inline.hpp"
43 #include "runtime/interfaceSupport.hpp"
44 #include "runtime/java.hpp"
45 #include "runtime/javaCalls.hpp"
46 #include "runtime/mutexLocker.hpp"
47 #include "runtime/osThread.hpp"
48 #include "runtime/sharedRuntime.hpp"
49 #include "runtime/stubRoutines.hpp"
50 #include "runtime/thread.inline.hpp"
51 #include "runtime/timer.hpp"
52 #include "utilities/events.hpp"
53 #include "utilities/vmError.hpp"
54
55 // Linux/Sparc has rather obscure naming of registers in sigcontext
56 // different between 32 and 64 bits
57 #define SIG_PC(x) ((x)->sigc_regs.tpc)
58 #define SIG_NPC(x) ((x)->sigc_regs.tnpc)
59 #define SIG_REGS(x) ((x)->sigc_regs)
60
61 // those are to reference registers in sigcontext
62 enum {
63 CON_G0 = 0,
64 CON_G1,
65 CON_G2,
66 CON_G3,
67 CON_G4,
68 CON_G5,
69 CON_G6,
70 CON_G7,
71 CON_O0,
72 CON_O1,
73 CON_O2,
74 CON_O3,
75 CON_O4,
76 CON_O5,
77 CON_O6,
78 CON_O7,
79 };
80
81 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
82 // currently interrupted by SIGPROF.
83 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested
84 // signal frames. Currently we don't do that on Linux, so it's the
85 // same as os::fetch_frame_from_context().
86 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
87 const ucontext_t* uc,
88 intptr_t** ret_sp,
89 intptr_t** ret_fp) {
90 assert(thread != NULL, "just checking");
91 assert(ret_sp != NULL, "just checking");
92 assert(ret_fp != NULL, "just checking");
93
94 return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
95 }
96
97 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
98 intptr_t** ret_sp,
99 intptr_t** ret_fp) {
100 const ucontext_t* uc = (const ucontext_t*) ucVoid;
101 ExtendedPC epc;
102
103 if (uc != NULL) {
104 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
105 if (ret_sp) {
106 *ret_sp = os::Linux::ucontext_get_sp(uc);
107 }
108 if (ret_fp) {
109 *ret_fp = (intptr_t*)NULL;
110 }
111 } else {
112 // construct empty ExtendedPC for return value checking
113 epc = ExtendedPC(NULL);
114 if (ret_sp) {
115 *ret_sp = (intptr_t*) NULL;
116 }
117 if (ret_fp) {
118 *ret_fp = (intptr_t*) NULL;
119 }
120 }
121
122 return epc;
123 }
124
125 frame os::fetch_frame_from_context(const void* ucVoid) {
126 intptr_t* sp;
127 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, NULL);
128 return frame(sp, frame::unpatchable, epc.pc());
129 }
130
131 frame os::get_sender_for_C_frame(frame* fr) {
132 return frame(fr->sender_sp(), frame::unpatchable, fr->sender_pc());
133 }
134
135 frame os::current_frame() {
136 intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
137 frame myframe(sp, frame::unpatchable,
138 CAST_FROM_FN_PTR(address, os::current_frame));
139 if (os::is_first_C_frame(&myframe)) {
140 // stack is not walkable
141 return frame(NULL, frame::unpatchable, NULL);
142 } else {
143 return os::get_sender_for_C_frame(&myframe);
144 }
145 }
146
147 address os::current_stack_pointer() {
148 register void *sp __asm__ ("sp");
149 return (address)sp;
150 }
151
152 char* os::non_memory_address_word() {
153 // Must never look like an address returned by reserve_memory,
154 // even in its subfields (as defined by the CPU immediate fields,
155 // if the CPU splits constants across multiple instructions).
156 // On SPARC, 0 != %hi(any real address), because there is no
157 // allocation in the first 1Kb of the virtual address space.
158 return (char*) 0;
159 }
160
161 void os::initialize_thread(Thread* thr) {}
162
163 void os::print_context(outputStream *st, const void *context) {
164 if (context == NULL) return;
165
166 const ucontext_t* uc = (const ucontext_t*)context;
167 sigcontext* sc = (sigcontext*)context;
168 st->print_cr("Registers:");
169
170 st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
171 " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
172 SIG_REGS(sc).u_regs[CON_G1],
173 SIG_REGS(sc).u_regs[CON_G2],
174 SIG_REGS(sc).u_regs[CON_G3],
175 SIG_REGS(sc).u_regs[CON_G4]);
176 st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
177 " G7=" INTPTR_FORMAT " Y=0x%x",
178 SIG_REGS(sc).u_regs[CON_G5],
179 SIG_REGS(sc).u_regs[CON_G6],
180 SIG_REGS(sc).u_regs[CON_G7],
181 SIG_REGS(sc).y);
182 st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
183 " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
184 SIG_REGS(sc).u_regs[CON_O0],
185 SIG_REGS(sc).u_regs[CON_O1],
186 SIG_REGS(sc).u_regs[CON_O2],
187 SIG_REGS(sc).u_regs[CON_O3]);
188 st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
189 " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
190 SIG_REGS(sc).u_regs[CON_O4],
191 SIG_REGS(sc).u_regs[CON_O5],
192 SIG_REGS(sc).u_regs[CON_O6],
193 SIG_REGS(sc).u_regs[CON_O7]);
194
195
196 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
197 st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
198 " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
199 sp[L0->sp_offset_in_saved_window()],
200 sp[L1->sp_offset_in_saved_window()],
201 sp[L2->sp_offset_in_saved_window()],
202 sp[L3->sp_offset_in_saved_window()]);
203 st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
204 " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
205 sp[L4->sp_offset_in_saved_window()],
206 sp[L5->sp_offset_in_saved_window()],
207 sp[L6->sp_offset_in_saved_window()],
208 sp[L7->sp_offset_in_saved_window()]);
209 st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
210 " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
211 sp[I0->sp_offset_in_saved_window()],
212 sp[I1->sp_offset_in_saved_window()],
213 sp[I2->sp_offset_in_saved_window()],
214 sp[I3->sp_offset_in_saved_window()]);
215 st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
216 " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
217 sp[I4->sp_offset_in_saved_window()],
218 sp[I5->sp_offset_in_saved_window()],
219 sp[I6->sp_offset_in_saved_window()],
220 sp[I7->sp_offset_in_saved_window()]);
221
222 st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
223 SIG_PC(sc),
224 SIG_NPC(sc));
225 st->cr();
226 st->cr();
227
228 st->print_cr("Top of Stack: (sp=" INTPTR_FORMAT ")", p2i(sp));
229 print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
230 st->cr();
231
232 // Note: it may be unsafe to inspect memory near pc. For example, pc may
233 // point to garbage if entry point in an nmethod is corrupted. Leave
234 // this at the end, and hope for the best.
235 address pc = os::Linux::ucontext_get_pc(uc);
236 st->print_cr("Instructions: (pc=" INTPTR_FORMAT ")", p2i(pc));
237 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
238 }
239
240
241 void os::print_register_info(outputStream *st, const void *context) {
242 if (context == NULL) return;
243
244 const ucontext_t *uc = (const ucontext_t*)context;
245 const sigcontext* sc = (const sigcontext*)context;
246 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
247
248 st->print_cr("Register to memory mapping:");
249 st->cr();
250
251 // this is only for the "general purpose" registers
252 st->print("G1="); print_location(st, SIG_REGS(sc).u_regs[CON_G1]);
253 st->print("G2="); print_location(st, SIG_REGS(sc).u_regs[CON_G2]);
254 st->print("G3="); print_location(st, SIG_REGS(sc).u_regs[CON_G3]);
255 st->print("G4="); print_location(st, SIG_REGS(sc).u_regs[CON_G4]);
256 st->print("G5="); print_location(st, SIG_REGS(sc).u_regs[CON_G5]);
257 st->print("G6="); print_location(st, SIG_REGS(sc).u_regs[CON_G6]);
258 st->print("G7="); print_location(st, SIG_REGS(sc).u_regs[CON_G7]);
259 st->cr();
260
261 st->print("O0="); print_location(st, SIG_REGS(sc).u_regs[CON_O0]);
262 st->print("O1="); print_location(st, SIG_REGS(sc).u_regs[CON_O1]);
263 st->print("O2="); print_location(st, SIG_REGS(sc).u_regs[CON_O2]);
264 st->print("O3="); print_location(st, SIG_REGS(sc).u_regs[CON_O3]);
265 st->print("O4="); print_location(st, SIG_REGS(sc).u_regs[CON_O4]);
266 st->print("O5="); print_location(st, SIG_REGS(sc).u_regs[CON_O5]);
267 st->print("O6="); print_location(st, SIG_REGS(sc).u_regs[CON_O6]);
268 st->print("O7="); print_location(st, SIG_REGS(sc).u_regs[CON_O7]);
269 st->cr();
270
271 st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
272 st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
273 st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
274 st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
275 st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
276 st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
277 st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
278 st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
279 st->cr();
280
281 st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
282 st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
283 st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
284 st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
285 st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
286 st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
287 st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
288 st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
289 st->cr();
290 }
291
292
293 address os::Linux::ucontext_get_pc(const ucontext_t* uc) {
294 return (address) SIG_PC((sigcontext*)uc);
295 }
296
297 void os::Linux::ucontext_set_pc(ucontext_t* uc, address pc) {
298 sigcontext* ctx = (sigcontext*) uc;
299 SIG_PC(ctx) = (intptr_t)pc;
300 SIG_NPC(ctx) = (intptr_t)(pc+4);
301 }
302
303 intptr_t* os::Linux::ucontext_get_sp(const ucontext_t *uc) {
304 return (intptr_t*)
305 ((intptr_t)SIG_REGS((sigcontext*)uc).u_regs[CON_O6] + STACK_BIAS);
306 }
307
308 // not used on Sparc
309 intptr_t* os::Linux::ucontext_get_fp(const ucontext_t *uc) {
310 ShouldNotReachHere();
311 return NULL;
312 }
313
314 // Utility functions
315
316 inline static bool checkPrefetch(sigcontext* uc, address pc) {
317 if (StubRoutines::is_safefetch_fault(pc)) {
318 os::Linux::ucontext_set_pc((ucontext_t*)uc, StubRoutines::continuation_for_safefetch_fault(pc));
319 return true;
320 }
321 return false;
322 }
323
324 inline static bool checkOverflow(sigcontext* uc,
325 address pc,
326 address addr,
327 JavaThread* thread,
328 address* stub) {
329 // check if fault address is within thread stack
330 if (thread->on_local_stack(addr)) {
331 // stack overflow
332 if (thread->in_stack_yellow_reserved_zone(addr)) {
333 thread->disable_stack_yellow_reserved_zone();
334 if (thread->thread_state() == _thread_in_Java) {
335 // Throw a stack overflow exception. Guard pages will be reenabled
336 // while unwinding the stack.
337 *stub =
338 SharedRuntime::continuation_for_implicit_exception(thread,
339 pc,
340 SharedRuntime::STACK_OVERFLOW);
341 } else {
342 // Thread was in the vm or native code. Return and try to finish.
343 return true;
344 }
345 } else if (thread->in_stack_red_zone(addr)) {
346 // Fatal red zone violation. Disable the guard pages and fall through
347 // to handle_unexpected_exception way down below.
348 thread->disable_stack_red_zone();
349 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
350
351 // This is a likely cause, but hard to verify. Let's just print
352 // it as a hint.
353 tty->print_raw_cr("Please check if any of your loaded .so files has "
354 "enabled executable stack (see man page execstack(8))");
355 } else {
356 // Accessing stack address below sp may cause SEGV if current
357 // thread has MAP_GROWSDOWN stack. This should only happen when
358 // current thread was created by user code with MAP_GROWSDOWN flag
359 // and then attached to VM. See notes in os_linux.cpp.
360 if (thread->osthread()->expanding_stack() == 0) {
361 thread->osthread()->set_expanding_stack();
362 if (os::Linux::manually_expand_stack(thread, addr)) {
363 thread->osthread()->clear_expanding_stack();
364 return true;
365 }
366 thread->osthread()->clear_expanding_stack();
367 } else {
368 fatal("recursive segv. expanding stack.");
369 }
370 }
371 }
372 return false;
373 }
374
375 inline static bool checkPollingPage(address pc, address fault, address* stub) {
376 if (fault == os::get_polling_page()) {
377 *stub = SharedRuntime::get_poll_stub(pc);
378 return true;
379 }
380 return false;
381 }
382
383 inline static bool checkByteBuffer(address pc, address npc, JavaThread * thread, address* stub) {
384 // BugId 4454115: A read from a MappedByteBuffer can fault
385 // here if the underlying file has been truncated.
386 // Do not crash the VM in such a case.
387 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
388 CompiledMethod* nm = cb->as_compiled_method_or_null();
389 if (nm != NULL && nm->has_unsafe_access()) {
390 *stub = SharedRuntime::handle_unsafe_access(thread, npc);
391 return true;
392 }
393 return false;
394 }
395
396 inline static bool checkVerifyOops(address pc, address fault, address* stub) {
397 if (pc >= MacroAssembler::_verify_oop_implicit_branch[0]
398 && pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
399 *stub = MacroAssembler::_verify_oop_implicit_branch[2];
400 warning("fixed up memory fault in +VerifyOops at address "
401 INTPTR_FORMAT, p2i(fault));
402 return true;
403 }
404 return false;
405 }
406
407 inline static bool checkFPFault(address pc, int code,
408 JavaThread* thread, address* stub) {
409 if (code == FPE_INTDIV || code == FPE_FLTDIV) {
410 *stub =
411 SharedRuntime::
412 continuation_for_implicit_exception(thread,
413 pc,
414 SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
415 return true;
416 }
417 return false;
418 }
419
420 inline static bool checkNullPointer(address pc, intptr_t fault,
421 JavaThread* thread, address* stub) {
422 if (!MacroAssembler::needs_explicit_null_check(fault)) {
423 // Determination of interpreter/vtable stub/compiled code null
424 // exception
425 *stub =
426 SharedRuntime::
427 continuation_for_implicit_exception(thread, pc,
428 SharedRuntime::IMPLICIT_NULL);
429 return true;
430 }
431 return false;
432 }
433
434 inline static bool checkFastJNIAccess(address pc, address* stub) {
435 address addr = JNI_FastGetField::find_slowcase_pc(pc);
436 if (addr != (address)-1) {
437 *stub = addr;
438 return true;
439 }
440 return false;
441 }
442
443 inline static bool checkSerializePage(JavaThread* thread, address addr) {
444 return os::is_memory_serialize_page(thread, addr);
445 }
446
447 inline static bool checkZombie(sigcontext* uc, address* pc, address* stub) {
448 if (nativeInstruction_at(*pc)->is_zombie()) {
449 // zombie method (ld [%g0],%o7 instruction)
450 *stub = SharedRuntime::get_handle_wrong_method_stub();
451
452 // At the stub it needs to look like a call from the caller of this
453 // method (not a call from the segv site).
454 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
455 return true;
456 }
457 return false;
458 }
459
460 inline static bool checkICMiss(sigcontext* uc, address* pc, address* stub) {
461 #ifdef COMPILER2
462 if (nativeInstruction_at(*pc)->is_ic_miss_trap()) {
463 #ifdef ASSERT
464 #ifdef TIERED
465 CodeBlob* cb = CodeCache::find_blob_unsafe(*pc);
466 assert(cb->is_compiled_by_c2(), "Wrong compiler");
467 #endif // TIERED
468 #endif // ASSERT
469 // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
470 *stub = SharedRuntime::get_ic_miss_stub();
471 // At the stub it needs to look like a call from the caller of this
472 // method (not a call from the segv site).
473 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
474 return true;
475 }
476 #endif // COMPILER2
477 return false;
478 }
479
480 extern "C" JNIEXPORT int
481 JVM_handle_linux_signal(int sig,
482 siginfo_t* info,
483 void* ucVoid,
484 int abort_if_unrecognized) {
485 // in fact this isn't ucontext_t* at all, but struct sigcontext*
486 // but Linux porting layer uses ucontext_t, so to minimize code change
487 // we cast as needed
488 ucontext_t* ucFake = (ucontext_t*) ucVoid;
489 sigcontext* uc = (sigcontext*)ucVoid;
490
491 Thread* t = Thread::current_or_null_safe();
492
493 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
494 // (no destructors can be run)
495 os::ThreadCrashProtection::check_crash_protection(sig, t);
496
497 SignalHandlerMark shm(t);
498
499 // Note: it's not uncommon that JNI code uses signal/sigset to install
500 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
501 // or have a SIGILL handler when detecting CPU type). When that happens,
502 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
503 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
504 // that do not require siginfo/ucontext first.
505
506 if (sig == SIGPIPE || sig == SIGXFSZ) {
507 // allow chained handler to go first
508 if (os::Linux::chained_handler(sig, info, ucVoid)) {
509 return true;
510 } else {
511 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
512 return true;
513 }
514 }
515
516 JavaThread* thread = NULL;
517 VMThread* vmthread = NULL;
518 if (os::Linux::signal_handlers_are_installed) {
519 if (t != NULL ){
520 if(t->is_Java_thread()) {
521 thread = (JavaThread*)t;
522 }
523 else if(t->is_VM_thread()){
524 vmthread = (VMThread *)t;
525 }
526 }
527 }
528
529 // decide if this trap can be handled by a stub
530 address stub = NULL;
531 address pc = NULL;
532 address npc = NULL;
533
534 //%note os_trap_1
535 if (info != NULL && uc != NULL && thread != NULL) {
536 pc = address(SIG_PC(uc));
537 npc = address(SIG_NPC(uc));
538
539 // Check to see if we caught the safepoint code in the
540 // process of write protecting the memory serialization page.
541 // It write enables the page immediately after protecting it
542 // so we can just return to retry the write.
543 if ((sig == SIGSEGV) && checkSerializePage(thread, (address)info->si_addr)) {
544 // Block current thread until the memory serialize page permission restored.
545 os::block_on_serialize_page_trap();
546 return 1;
547 }
548
549 if (checkPrefetch(uc, pc)) {
550 return 1;
551 }
552
553 // Handle ALL stack overflow variations here
554 if (sig == SIGSEGV) {
555 if (checkOverflow(uc, pc, (address)info->si_addr, thread, &stub)) {
556 return 1;
557 }
558 }
559
560 if (sig == SIGBUS &&
561 thread->thread_state() == _thread_in_vm &&
562 thread->doing_unsafe_access()) {
563 stub = SharedRuntime::handle_unsafe_access(thread, npc);
564 }
565
566 if (thread->thread_state() == _thread_in_Java) {
567 do {
568 // Java thread running in Java code => find exception handler if any
569 // a fault inside compiled code, the interpreter, or a stub
570
571 if ((sig == SIGSEGV) && checkPollingPage(pc, (address)info->si_addr, &stub)) {
572 break;
573 }
574
575 if ((sig == SIGBUS) && checkByteBuffer(pc, npc, thread, &stub)) {
576 break;
577 }
578
579 if ((sig == SIGSEGV || sig == SIGBUS) &&
580 checkVerifyOops(pc, (address)info->si_addr, &stub)) {
581 break;
582 }
583
584 if ((sig == SIGSEGV) && checkZombie(uc, &pc, &stub)) {
585 break;
586 }
587
588 if ((sig == SIGILL) && checkICMiss(uc, &pc, &stub)) {
589 break;
590 }
591
592 if ((sig == SIGFPE) && checkFPFault(pc, info->si_code, thread, &stub)) {
593 break;
594 }
595
596 if ((sig == SIGSEGV) &&
597 checkNullPointer(pc, (intptr_t)info->si_addr, thread, &stub)) {
598 break;
599 }
600 } while (0);
601
602 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
603 // and the heap gets shrunk before the field access.
604 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
605 checkFastJNIAccess(pc, &stub);
606 }
607 }
608
609 if (stub != NULL) {
610 // save all thread context in case we need to restore it
611 thread->set_saved_exception_pc(pc);
612 thread->set_saved_exception_npc(npc);
613 os::Linux::ucontext_set_pc((ucontext_t*)uc, stub);
614 return true;
615 }
616 }
617
618 // signal-chaining
619 if (os::Linux::chained_handler(sig, info, ucVoid)) {
620 return true;
621 }
622
623 if (!abort_if_unrecognized) {
624 // caller wants another chance, so give it to him
625 return false;
626 }
627
628 if (pc == NULL && uc != NULL) {
629 pc = os::Linux::ucontext_get_pc((const ucontext_t*)uc);
630 }
631
632 // unmask current signal
633 sigset_t newset;
634 sigemptyset(&newset);
635 sigaddset(&newset, sig);
636 sigprocmask(SIG_UNBLOCK, &newset, NULL);
637
638 VMError::report_and_die(t, sig, pc, info, ucVoid);
639
640 ShouldNotReachHere();
641 return false;
642 }
643
644 void os::Linux::init_thread_fpu_state(void) {
645 // Nothing to do
646 }
647
648 int os::Linux::get_fpu_control_word() {
649 return 0;
650 }
651
652 void os::Linux::set_fpu_control_word(int fpu) {
653 // nothing
654 }
655
656 bool os::is_allocatable(size_t bytes) {
657 return true;
658 }
659
660 ///////////////////////////////////////////////////////////////////////////////
661 // thread stack
662
663 // Minimum usable stack sizes required to get to user code. Space for
664 // HotSpot guard pages is added later.
665 size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K;
666 size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
667 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
668
669 // return default stack size for thr_type
670 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
671 // default stack size (compiler thread needs larger stack)
672 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
673 return s;
674 }
675
676 #ifndef PRODUCT
677 void os::verify_stack_alignment() {
678 }
679 #endif
680
681 int os::extra_bang_size_in_bytes() {
682 // SPARC does not require the additional stack bang.
683 return 0;
684 }