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 static void current_stack_region(address* bottom, size_t* size) {
160 if (os::Linux::is_initial_thread()) {
161 // initial thread needs special handling because pthread_getattr_np()
162 // may return bogus value.
163 *bottom = os::Linux::initial_thread_stack_bottom();
164 *size = os::Linux::initial_thread_stack_size();
165 } else {
166 pthread_attr_t attr;
167
168 int rslt = pthread_getattr_np(pthread_self(), &attr);
169
170 // JVM needs to know exact stack location, abort if it fails
171 if (rslt != 0) {
172 if (rslt == ENOMEM) {
173 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
174 } else {
175 fatal("pthread_getattr_np failed with errno = %d", rslt);
176 }
177 }
178
179 if (pthread_attr_getstack(&attr, (void**)bottom, size) != 0) {
180 fatal("Can not locate current stack attributes!");
181 }
182
183 pthread_attr_destroy(&attr);
184 }
185 assert(os::current_stack_pointer() >= *bottom &&
186 os::current_stack_pointer() < *bottom + *size, "just checking");
187 }
188
189 address os::current_stack_base() {
190 address bottom;
191 size_t size;
192 current_stack_region(&bottom, &size);
193 return bottom + size;
194 }
195
196 size_t os::current_stack_size() {
197 // stack size includes normal stack and HotSpot guard pages
198 address bottom;
199 size_t size;
200 current_stack_region(&bottom, &size);
201 return size;
202 }
203
204 char* os::non_memory_address_word() {
205 // Must never look like an address returned by reserve_memory,
206 // even in its subfields (as defined by the CPU immediate fields,
207 // if the CPU splits constants across multiple instructions).
208 // On SPARC, 0 != %hi(any real address), because there is no
209 // allocation in the first 1Kb of the virtual address space.
210 return (char*) 0;
211 }
212
213 void os::initialize_thread(Thread* thr) {}
214
215 void os::print_context(outputStream *st, const void *context) {
216 if (context == NULL) return;
217
218 const ucontext_t* uc = (const ucontext_t*)context;
219 sigcontext* sc = (sigcontext*)context;
220 st->print_cr("Registers:");
221
222 st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
223 " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
224 SIG_REGS(sc).u_regs[CON_G1],
225 SIG_REGS(sc).u_regs[CON_G2],
226 SIG_REGS(sc).u_regs[CON_G3],
227 SIG_REGS(sc).u_regs[CON_G4]);
228 st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
229 " G7=" INTPTR_FORMAT " Y=0x%x",
230 SIG_REGS(sc).u_regs[CON_G5],
231 SIG_REGS(sc).u_regs[CON_G6],
232 SIG_REGS(sc).u_regs[CON_G7],
233 SIG_REGS(sc).y);
234 st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
235 " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
236 SIG_REGS(sc).u_regs[CON_O0],
237 SIG_REGS(sc).u_regs[CON_O1],
238 SIG_REGS(sc).u_regs[CON_O2],
239 SIG_REGS(sc).u_regs[CON_O3]);
240 st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
241 " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
242 SIG_REGS(sc).u_regs[CON_O4],
243 SIG_REGS(sc).u_regs[CON_O5],
244 SIG_REGS(sc).u_regs[CON_O6],
245 SIG_REGS(sc).u_regs[CON_O7]);
246
247
248 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
249 st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
250 " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
251 sp[L0->sp_offset_in_saved_window()],
252 sp[L1->sp_offset_in_saved_window()],
253 sp[L2->sp_offset_in_saved_window()],
254 sp[L3->sp_offset_in_saved_window()]);
255 st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
256 " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
257 sp[L4->sp_offset_in_saved_window()],
258 sp[L5->sp_offset_in_saved_window()],
259 sp[L6->sp_offset_in_saved_window()],
260 sp[L7->sp_offset_in_saved_window()]);
261 st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
262 " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
263 sp[I0->sp_offset_in_saved_window()],
264 sp[I1->sp_offset_in_saved_window()],
265 sp[I2->sp_offset_in_saved_window()],
266 sp[I3->sp_offset_in_saved_window()]);
267 st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
268 " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
269 sp[I4->sp_offset_in_saved_window()],
270 sp[I5->sp_offset_in_saved_window()],
271 sp[I6->sp_offset_in_saved_window()],
272 sp[I7->sp_offset_in_saved_window()]);
273
274 st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
275 SIG_PC(sc),
276 SIG_NPC(sc));
277 st->cr();
278 st->cr();
279
280 st->print_cr("Top of Stack: (sp=" INTPTR_FORMAT ")", p2i(sp));
281 print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
282 st->cr();
283
284 // Note: it may be unsafe to inspect memory near pc. For example, pc may
285 // point to garbage if entry point in an nmethod is corrupted. Leave
286 // this at the end, and hope for the best.
287 address pc = os::Linux::ucontext_get_pc(uc);
288 st->print_cr("Instructions: (pc=" INTPTR_FORMAT ")", p2i(pc));
289 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
290 }
291
292
293 void os::print_register_info(outputStream *st, const void *context) {
294 if (context == NULL) return;
295
296 const ucontext_t *uc = (const ucontext_t*)context;
297 const sigcontext* sc = (const sigcontext*)context;
298 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
299
300 st->print_cr("Register to memory mapping:");
301 st->cr();
302
303 // this is only for the "general purpose" registers
304 st->print("G1="); print_location(st, SIG_REGS(sc).u_regs[CON_G1]);
305 st->print("G2="); print_location(st, SIG_REGS(sc).u_regs[CON_G2]);
306 st->print("G3="); print_location(st, SIG_REGS(sc).u_regs[CON_G3]);
307 st->print("G4="); print_location(st, SIG_REGS(sc).u_regs[CON_G4]);
308 st->print("G5="); print_location(st, SIG_REGS(sc).u_regs[CON_G5]);
309 st->print("G6="); print_location(st, SIG_REGS(sc).u_regs[CON_G6]);
310 st->print("G7="); print_location(st, SIG_REGS(sc).u_regs[CON_G7]);
311 st->cr();
312
313 st->print("O0="); print_location(st, SIG_REGS(sc).u_regs[CON_O0]);
314 st->print("O1="); print_location(st, SIG_REGS(sc).u_regs[CON_O1]);
315 st->print("O2="); print_location(st, SIG_REGS(sc).u_regs[CON_O2]);
316 st->print("O3="); print_location(st, SIG_REGS(sc).u_regs[CON_O3]);
317 st->print("O4="); print_location(st, SIG_REGS(sc).u_regs[CON_O4]);
318 st->print("O5="); print_location(st, SIG_REGS(sc).u_regs[CON_O5]);
319 st->print("O6="); print_location(st, SIG_REGS(sc).u_regs[CON_O6]);
320 st->print("O7="); print_location(st, SIG_REGS(sc).u_regs[CON_O7]);
321 st->cr();
322
323 st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
324 st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
325 st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
326 st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
327 st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
328 st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
329 st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
330 st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
331 st->cr();
332
333 st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
334 st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
335 st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
336 st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
337 st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
338 st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
339 st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
340 st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
341 st->cr();
342 }
343
344
345 address os::Linux::ucontext_get_pc(const ucontext_t* uc) {
346 return (address) SIG_PC((sigcontext*)uc);
347 }
348
349 void os::Linux::ucontext_set_pc(ucontext_t* uc, address pc) {
350 sigcontext* ctx = (sigcontext*) uc;
351 SIG_PC(ctx) = (intptr_t)pc;
352 SIG_NPC(ctx) = (intptr_t)(pc+4);
353 }
354
355 intptr_t* os::Linux::ucontext_get_sp(const 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(const ucontext_t *uc) {
362 ShouldNotReachHere();
363 return NULL;
364 }
365
366 // Utility functions
367
368 inline static bool checkPrefetch(sigcontext* uc, address pc) {
369 if (StubRoutines::is_safefetch_fault(pc)) {
370 os::Linux::ucontext_set_pc((ucontext_t*)uc, StubRoutines::continuation_for_safefetch_fault(pc));
371 return true;
372 }
373 return false;
374 }
375
376 inline static bool checkOverflow(sigcontext* uc,
377 address pc,
378 address addr,
379 JavaThread* thread,
380 address* stub) {
381 // check if fault address is within thread stack
382 if (thread->on_local_stack(addr)) {
383 // stack overflow
384 if (thread->in_stack_yellow_reserved_zone(addr)) {
385 thread->disable_stack_yellow_reserved_zone();
386 if (thread->thread_state() == _thread_in_Java) {
387 // Throw a stack overflow exception. Guard pages will be reenabled
388 // while unwinding the stack.
389 *stub =
390 SharedRuntime::continuation_for_implicit_exception(thread,
391 pc,
392 SharedRuntime::STACK_OVERFLOW);
393 } else {
394 // Thread was in the vm or native code. Return and try to finish.
395 return true;
396 }
397 } else if (thread->in_stack_red_zone(addr)) {
398 // Fatal red zone violation. Disable the guard pages and fall through
399 // to handle_unexpected_exception way down below.
400 thread->disable_stack_red_zone();
401 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
402
403 // This is a likely cause, but hard to verify. Let's just print
404 // it as a hint.
405 tty->print_raw_cr("Please check if any of your loaded .so files has "
406 "enabled executable stack (see man page execstack(8))");
407 } else {
408 // Accessing stack address below sp may cause SEGV if current
409 // thread has MAP_GROWSDOWN stack. This should only happen when
410 // current thread was created by user code with MAP_GROWSDOWN flag
411 // and then attached to VM. See notes in os_linux.cpp.
412 if (thread->osthread()->expanding_stack() == 0) {
413 thread->osthread()->set_expanding_stack();
414 if (os::Linux::manually_expand_stack(thread, addr)) {
415 thread->osthread()->clear_expanding_stack();
416 return true;
417 }
418 thread->osthread()->clear_expanding_stack();
419 } else {
420 fatal("recursive segv. expanding stack.");
421 }
422 }
423 }
424 return false;
425 }
426
427 inline static bool checkPollingPage(address pc, address fault, address* stub) {
428 if (fault == os::get_polling_page()) {
429 *stub = SharedRuntime::get_poll_stub(pc);
430 return true;
431 }
432 return false;
433 }
434
435 inline static bool checkByteBuffer(address pc, address npc, address* stub) {
436 // BugId 4454115: A read from a MappedByteBuffer can fault
437 // here if the underlying file has been truncated.
438 // Do not crash the VM in such a case.
439 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
440 CompiledMethod* nm = cb->as_compiled_method_or_null();
441 if (nm != NULL && nm->has_unsafe_access()) {
442 *stub = SharedRuntime::handle_unsafe_access(thread, npc);
443 return true;
444 }
445 return false;
446 }
447
448 inline static bool checkVerifyOops(address pc, address fault, address* stub) {
449 if (pc >= MacroAssembler::_verify_oop_implicit_branch[0]
450 && pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
451 *stub = MacroAssembler::_verify_oop_implicit_branch[2];
452 warning("fixed up memory fault in +VerifyOops at address "
453 INTPTR_FORMAT, p2i(fault));
454 return true;
455 }
456 return false;
457 }
458
459 inline static bool checkFPFault(address pc, int code,
460 JavaThread* thread, address* stub) {
461 if (code == FPE_INTDIV || code == FPE_FLTDIV) {
462 *stub =
463 SharedRuntime::
464 continuation_for_implicit_exception(thread,
465 pc,
466 SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
467 return true;
468 }
469 return false;
470 }
471
472 inline static bool checkNullPointer(address pc, intptr_t fault,
473 JavaThread* thread, address* stub) {
474 if (!MacroAssembler::needs_explicit_null_check(fault)) {
475 // Determination of interpreter/vtable stub/compiled code null
476 // exception
477 *stub =
478 SharedRuntime::
479 continuation_for_implicit_exception(thread, pc,
480 SharedRuntime::IMPLICIT_NULL);
481 return true;
482 }
483 return false;
484 }
485
486 inline static bool checkFastJNIAccess(address pc, address* stub) {
487 address addr = JNI_FastGetField::find_slowcase_pc(pc);
488 if (addr != (address)-1) {
489 *stub = addr;
490 return true;
491 }
492 return false;
493 }
494
495 inline static bool checkSerializePage(JavaThread* thread, address addr) {
496 return os::is_memory_serialize_page(thread, addr);
497 }
498
499 inline static bool checkZombie(sigcontext* uc, address* pc, address* stub) {
500 if (nativeInstruction_at(*pc)->is_zombie()) {
501 // zombie method (ld [%g0],%o7 instruction)
502 *stub = SharedRuntime::get_handle_wrong_method_stub();
503
504 // At the stub it needs to look like a call from the caller of this
505 // method (not a call from the segv site).
506 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
507 return true;
508 }
509 return false;
510 }
511
512 inline static bool checkICMiss(sigcontext* uc, address* pc, address* stub) {
513 #ifdef COMPILER2
514 if (nativeInstruction_at(*pc)->is_ic_miss_trap()) {
515 #ifdef ASSERT
516 #ifdef TIERED
517 CodeBlob* cb = CodeCache::find_blob_unsafe(*pc);
518 assert(cb->is_compiled_by_c2(), "Wrong compiler");
519 #endif // TIERED
520 #endif // ASSERT
521 // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
522 *stub = SharedRuntime::get_ic_miss_stub();
523 // At the stub it needs to look like a call from the caller of this
524 // method (not a call from the segv site).
525 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
526 return true;
527 }
528 #endif // COMPILER2
529 return false;
530 }
531
532 extern "C" JNIEXPORT int
533 JVM_handle_linux_signal(int sig,
534 siginfo_t* info,
535 void* ucVoid,
536 int abort_if_unrecognized) {
537 // in fact this isn't ucontext_t* at all, but struct sigcontext*
538 // but Linux porting layer uses ucontext_t, so to minimize code change
539 // we cast as needed
540 ucontext_t* ucFake = (ucontext_t*) ucVoid;
541 sigcontext* uc = (sigcontext*)ucVoid;
542
543 Thread* t = Thread::current_or_null_safe();
544
545 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
546 // (no destructors can be run)
547 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
548
549 SignalHandlerMark shm(t);
550
551 // Note: it's not uncommon that JNI code uses signal/sigset to install
552 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
553 // or have a SIGILL handler when detecting CPU type). When that happens,
554 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
555 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
556 // that do not require siginfo/ucontext first.
557
558 if (sig == SIGPIPE || sig == SIGXFSZ) {
559 // allow chained handler to go first
560 if (os::Linux::chained_handler(sig, info, ucVoid)) {
561 return true;
562 } else {
563 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
564 return true;
565 }
566 }
567
568 JavaThread* thread = NULL;
569 VMThread* vmthread = NULL;
570 if (os::Linux::signal_handlers_are_installed) {
571 if (t != NULL ){
572 if(t->is_Java_thread()) {
573 thread = (JavaThread*)t;
574 }
575 else if(t->is_VM_thread()){
576 vmthread = (VMThread *)t;
577 }
578 }
579 }
580
581 // decide if this trap can be handled by a stub
582 address stub = NULL;
583 address pc = NULL;
584 address npc = NULL;
585
586 //%note os_trap_1
587 if (info != NULL && uc != NULL && thread != NULL) {
588 pc = address(SIG_PC(uc));
589 npc = address(SIG_NPC(uc));
590
591 // Check to see if we caught the safepoint code in the
592 // process of write protecting the memory serialization page.
593 // It write enables the page immediately after protecting it
594 // so we can just return to retry the write.
595 if ((sig == SIGSEGV) && checkSerializePage(thread, (address)info->si_addr)) {
596 // Block current thread until the memory serialize page permission restored.
597 os::block_on_serialize_page_trap();
598 return 1;
599 }
600
601 if (checkPrefetch(uc, pc)) {
602 return 1;
603 }
604
605 // Handle ALL stack overflow variations here
606 if (sig == SIGSEGV) {
607 if (checkOverflow(uc, pc, (address)info->si_addr, thread, &stub)) {
608 return 1;
609 }
610 }
611
612 if (sig == SIGBUS &&
613 thread->thread_state() == _thread_in_vm &&
614 thread->doing_unsafe_access()) {
615 stub = SharedRuntime::handle_unsafe_access(thread, npc);
616 }
617
618 if (thread->thread_state() == _thread_in_Java) {
619 do {
620 // Java thread running in Java code => find exception handler if any
621 // a fault inside compiled code, the interpreter, or a stub
622
623 if ((sig == SIGSEGV) && checkPollingPage(pc, (address)info->si_addr, &stub)) {
624 break;
625 }
626
627 if ((sig == SIGBUS) && checkByteBuffer(pc, npc, &stub)) {
628 break;
629 }
630
631 if ((sig == SIGSEGV || sig == SIGBUS) &&
632 checkVerifyOops(pc, (address)info->si_addr, &stub)) {
633 break;
634 }
635
636 if ((sig == SIGSEGV) && checkZombie(uc, &pc, &stub)) {
637 break;
638 }
639
640 if ((sig == SIGILL) && checkICMiss(uc, &pc, &stub)) {
641 break;
642 }
643
644 if ((sig == SIGFPE) && checkFPFault(pc, info->si_code, thread, &stub)) {
645 break;
646 }
647
648 if ((sig == SIGSEGV) &&
649 checkNullPointer(pc, (intptr_t)info->si_addr, thread, &stub)) {
650 break;
651 }
652 } while (0);
653
654 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
655 // and the heap gets shrunk before the field access.
656 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
657 checkFastJNIAccess(pc, &stub);
658 }
659 }
660
661 if (stub != NULL) {
662 // save all thread context in case we need to restore it
663 thread->set_saved_exception_pc(pc);
664 thread->set_saved_exception_npc(npc);
665 os::Linux::ucontext_set_pc((ucontext_t*)uc, stub);
666 return true;
667 }
668 }
669
670 // signal-chaining
671 if (os::Linux::chained_handler(sig, info, ucVoid)) {
672 return true;
673 }
674
675 if (!abort_if_unrecognized) {
676 // caller wants another chance, so give it to him
677 return false;
678 }
679
680 if (pc == NULL && uc != NULL) {
681 pc = os::Linux::ucontext_get_pc((const ucontext_t*)uc);
682 }
683
684 // unmask current signal
685 sigset_t newset;
686 sigemptyset(&newset);
687 sigaddset(&newset, sig);
688 sigprocmask(SIG_UNBLOCK, &newset, NULL);
689
690 VMError::report_and_die(t, sig, pc, info, ucVoid);
691
692 ShouldNotReachHere();
693 return false;
694 }
695
696 void os::Linux::init_thread_fpu_state(void) {
697 // Nothing to do
698 }
699
700 int os::Linux::get_fpu_control_word() {
701 return 0;
702 }
703
704 void os::Linux::set_fpu_control_word(int fpu) {
705 // nothing
706 }
707
708 bool os::is_allocatable(size_t bytes) {
709 #ifdef _LP64
710 return true;
711 #else
712 if (bytes < 2 * G) {
713 return true;
714 }
715
716 char* addr = reserve_memory(bytes, NULL);
717
718 if (addr != NULL) {
719 release_memory(addr, bytes);
720 }
721
722 return addr != NULL;
723 #endif // _LP64
724 }
725
726 ///////////////////////////////////////////////////////////////////////////////
727 // thread stack
728
729 size_t os::Linux::min_stack_allowed = 128 * K;
730
731 // return default stack size for thr_type
732 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
733 // default stack size (compiler thread needs larger stack)
734 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
735 return s;
736 }
737
738 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
739 // Creating guard page is very expensive. Java thread has HotSpot
740 // guard page, only enable glibc guard page for non-Java threads.
741 return (thr_type == java_thread ? 0 : page_size());
742 }
743
744 #ifndef PRODUCT
745 void os::verify_stack_alignment() {
746 }
747 #endif
748
749 int os::extra_bang_size_in_bytes() {
750 // SPARC does not require the additional stack bang.
751 return 0;
752 }