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 "asm/macroAssembler.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_solaris.h"
34 #include "memory/allocation.inline.hpp"
35 #include "mutex_solaris.inline.hpp"
36 #include "os_share_solaris.hpp"
37 #include "prims/jniFastGetField.hpp"
38 #include "prims/jvm.h"
39 #include "prims/jvm_misc.hpp"
40 #include "runtime/arguments.hpp"
41 #include "runtime/atomic.inline.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 // put OS-includes here
57 # include <sys/types.h>
58 # include <sys/mman.h>
59 # include <pthread.h>
60 # include <signal.h>
61 # include <setjmp.h>
62 # include <errno.h>
63 # include <dlfcn.h>
64 # include <stdio.h>
65 # include <unistd.h>
66 # include <sys/resource.h>
67 # include <thread.h>
68 # include <sys/stat.h>
69 # include <sys/time.h>
70 # include <sys/filio.h>
71 # include <sys/utsname.h>
72 # include <sys/systeminfo.h>
73 # include <sys/socket.h>
74 # include <sys/trap.h>
75 # include <sys/lwp.h>
76 # include <pwd.h>
77 # include <poll.h>
78 # include <sys/lwp.h>
79 # include <procfs.h> // see comment in <sys/procfs.h>
80
81 #ifndef AMD64
82 // QQQ seems useless at this point
83 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
84 #endif // AMD64
85 # include <sys/procfs.h> // see comment in <sys/procfs.h>
86
87
88 #define MAX_PATH (2 * K)
89
90 // Minimum stack size for the VM. It's easier to document a constant value
91 // but it's different for x86 and sparc because the page sizes are different.
92 #ifdef AMD64
93 size_t os::Solaris::min_stack_allowed = 224*K;
94 #define REG_SP REG_RSP
95 #define REG_PC REG_RIP
96 #define REG_FP REG_RBP
97 #else
98 size_t os::Solaris::min_stack_allowed = 64*K;
99 #define REG_SP UESP
100 #define REG_PC EIP
101 #define REG_FP EBP
102 // 4900493 counter to prevent runaway LDTR refresh attempt
103
104 static volatile int ldtr_refresh = 0;
105 // the libthread instruction that faults because of the stale LDTR
106
107 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
108 };
109 #endif // AMD64
110
111 char* os::non_memory_address_word() {
112 // Must never look like an address returned by reserve_memory,
113 // even in its subfields (as defined by the CPU immediate fields,
114 // if the CPU splits constants across multiple instructions).
115 return (char*) -1;
116 }
117
118 //
119 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
120 // There are issues with libthread giving out uc_links for different threads
121 // on the same uc_link chain and bad or circular links.
122 //
123 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
124 if (valid >= suspect ||
125 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
126 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
127 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
128 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
129 return false;
130 }
131
132 if (thread->is_Java_thread()) {
133 if (!valid_stack_address(thread, (address)suspect)) {
134 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
135 return false;
136 }
137 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
138 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
139 return false;
140 }
141 }
142 return true;
143 }
144
145 // We will only follow one level of uc_link since there are libthread
146 // issues with ucontext linking and it is better to be safe and just
147 // let caller retry later.
148 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
149 ucontext_t *uc) {
150
151 ucontext_t *retuc = NULL;
152
153 if (uc != NULL) {
154 if (uc->uc_link == NULL) {
155 // cannot validate without uc_link so accept current ucontext
156 retuc = uc;
157 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
158 // first ucontext is valid so try the next one
159 uc = uc->uc_link;
160 if (uc->uc_link == NULL) {
161 // cannot validate without uc_link so accept current ucontext
162 retuc = uc;
163 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
164 // the ucontext one level down is also valid so return it
165 retuc = uc;
166 }
167 }
168 }
169 return retuc;
170 }
171
172 // Assumes ucontext is valid
173 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
174 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
175 }
176
177 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) {
178 uc->uc_mcontext.gregs [REG_PC] = (greg_t) pc;
179 }
180
181 // Assumes ucontext is valid
182 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
183 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
184 }
185
186 // Assumes ucontext is valid
187 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
188 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
189 }
190
191 address os::Solaris::ucontext_get_pc(ucontext_t *uc) {
192 return (address) uc->uc_mcontext.gregs[REG_PC];
193 }
194
195 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
196 // is currently interrupted by SIGPROF.
197 //
198 // The difference between this and os::fetch_frame_from_context() is that
199 // here we try to skip nested signal frames.
200 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
201 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
202
203 assert(thread != NULL, "just checking");
204 assert(ret_sp != NULL, "just checking");
205 assert(ret_fp != NULL, "just checking");
206
207 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
208 return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
209 }
210
211 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
212 intptr_t** ret_sp, intptr_t** ret_fp) {
213
214 ExtendedPC epc;
215 ucontext_t *uc = (ucontext_t*)ucVoid;
216
217 if (uc != NULL) {
218 epc = os::Solaris::ucontext_get_ExtendedPC(uc);
219 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
220 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc);
221 } else {
222 // construct empty ExtendedPC for return value checking
223 epc = ExtendedPC(NULL);
224 if (ret_sp) *ret_sp = (intptr_t *)NULL;
225 if (ret_fp) *ret_fp = (intptr_t *)NULL;
226 }
227
228 return epc;
229 }
230
231 frame os::fetch_frame_from_context(void* ucVoid) {
232 intptr_t* sp;
233 intptr_t* fp;
234 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
235 return frame(sp, fp, epc.pc());
236 }
237
238 frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) {
239 intptr_t* sp;
240 intptr_t* fp;
241 ExtendedPC epc = os::Solaris::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp);
242 return frame(sp, fp, epc.pc());
243 }
244
245 bool os::Solaris::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
246 address pc = (address) os::Solaris::ucontext_get_pc(uc);
247 if (Interpreter::contains(pc)) {
248 // interpreter performs stack banging after the fixed frame header has
249 // been generated while the compilers perform it before. To maintain
250 // semantic consistency between interpreted and compiled frames, the
251 // method returns the Java sender of the current frame.
252 *fr = os::fetch_frame_from_ucontext(thread, uc);
253 assert(fr->safe_for_sender(thread), "Safety check");
254 if (!fr->is_first_java_frame()) {
255 *fr = fr->java_sender();
256 }
257 } else {
258 // more complex code with compiled code
259 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
260 CodeBlob* cb = CodeCache::find_blob(pc);
261 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
262 // Not sure where the pc points to, fallback to default
263 // stack overflow handling
264 return false;
265 } else {
266 // in compiled code, the stack banging is performed just after the return pc
267 // has been pushed on the stack
268 intptr_t* fp = os::Solaris::ucontext_get_fp(uc);
269 intptr_t* sp = os::Solaris::ucontext_get_sp(uc);
270 *fr = frame(sp + 1, fp, (address)*sp);
271 if (!fr->is_java_frame()) {
272 assert(fr->safe_for_sender(thread), "Safety check");
273 *fr = fr->java_sender();
274 }
275 }
276 }
277 assert(fr->is_java_frame(), "Safety check");
278 return true;
279 }
280
281 frame os::get_sender_for_C_frame(frame* fr) {
282 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
283 }
284
285 extern "C" intptr_t *_get_current_sp(); // in .il file
286
287 address os::current_stack_pointer() {
288 return (address)_get_current_sp();
289 }
290
291 extern "C" intptr_t *_get_current_fp(); // in .il file
292
293 frame os::current_frame() {
294 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
295 frame myframe((intptr_t*)os::current_stack_pointer(),
296 (intptr_t*)fp,
297 CAST_FROM_FN_PTR(address, os::current_frame));
298 if (os::is_first_C_frame(&myframe)) {
299 // stack is not walkable
300 frame ret; // This will be a null useless frame
301 return ret;
302 } else {
303 return os::get_sender_for_C_frame(&myframe);
304 }
305 }
306
307 #ifndef AMD64
308
309 // Detecting SSE support by OS
310 // From solaris_i486.s
311 extern "C" bool sse_check();
312 extern "C" bool sse_unavailable();
313
314 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
315 static int sse_status = SSE_UNKNOWN;
316
317
318 static void check_for_sse_support() {
319 if (!VM_Version::supports_sse()) {
320 sse_status = SSE_NOT_SUPPORTED;
321 return;
322 }
323 // looking for _sse_hw in libc.so, if it does not exist or
324 // the value (int) is 0, OS has no support for SSE
325 int *sse_hwp;
326 void *h;
327
328 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
329 //open failed, presume no support for SSE
330 sse_status = SSE_NOT_SUPPORTED;
331 return;
332 }
333 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
334 sse_status = SSE_NOT_SUPPORTED;
335 } else if (*sse_hwp == 0) {
336 sse_status = SSE_NOT_SUPPORTED;
337 }
338 dlclose(h);
339
340 if (sse_status == SSE_UNKNOWN) {
341 bool (*try_sse)() = (bool (*)())sse_check;
342 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
343 }
344
345 }
346
347 #endif // AMD64
348
349 bool os::supports_sse() {
350 #ifdef AMD64
351 return true;
352 #else
353 if (sse_status == SSE_UNKNOWN)
354 check_for_sse_support();
355 return sse_status == SSE_SUPPORTED;
356 #endif // AMD64
357 }
358
359 bool os::is_allocatable(size_t bytes) {
360 #ifdef AMD64
361 return true;
362 #else
363
364 if (bytes < 2 * G) {
365 return true;
366 }
367
368 char* addr = reserve_memory(bytes, NULL);
369
370 if (addr != NULL) {
371 release_memory(addr, bytes);
372 }
373
374 return addr != NULL;
375 #endif // AMD64
376
377 }
378
379 extern "C" JNIEXPORT int
380 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid,
381 int abort_if_unrecognized) {
382 ucontext_t* uc = (ucontext_t*) ucVoid;
383
384 #ifndef AMD64
385 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
386 // the SSE instruction faulted. supports_sse() need return false.
387 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
388 return true;
389 }
390 #endif // !AMD64
391
392 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
393
394 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
395 // (no destructors can be run)
396 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
397
398 SignalHandlerMark shm(t);
399
400 if(sig == SIGPIPE || sig == SIGXFSZ) {
401 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
402 return true;
403 } else {
404 if (PrintMiscellaneous && (WizardMode || Verbose)) {
405 char buf[64];
406 warning("Ignoring %s - see 4229104 or 6499219",
407 os::exception_name(sig, buf, sizeof(buf)));
408
409 }
410 return true;
411 }
412 }
413
414 JavaThread* thread = NULL;
415 VMThread* vmthread = NULL;
416
417 if (os::Solaris::signal_handlers_are_installed) {
418 if (t != NULL ){
419 if(t->is_Java_thread()) {
420 thread = (JavaThread*)t;
421 }
422 else if(t->is_VM_thread()){
423 vmthread = (VMThread *)t;
424 }
425 }
426 }
427
428 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
429
430 if (sig == os::Solaris::SIGasync()) {
431 if(thread || vmthread){
432 OSThread::SR_handler(t, uc);
433 return true;
434 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
435 return true;
436 } else {
437 // If os::Solaris::SIGasync not chained, and this is a non-vm and
438 // non-java thread
439 return true;
440 }
441 }
442
443 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
444 // can't decode this kind of signal
445 info = NULL;
446 } else {
447 assert(sig == info->si_signo, "bad siginfo");
448 }
449
450 // decide if this trap can be handled by a stub
451 address stub = NULL;
452
453 address pc = NULL;
454
455 //%note os_trap_1
456 if (info != NULL && uc != NULL && thread != NULL) {
457 // factor me: getPCfromContext
458 pc = (address) uc->uc_mcontext.gregs[REG_PC];
459
460 if (StubRoutines::is_safefetch_fault(pc)) {
461 os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
462 return true;
463 }
464
465 // Handle ALL stack overflow variations here
466 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
467 address addr = (address) info->si_addr;
468 if (thread->in_stack_yellow_zone(addr)) {
469 if (thread->thread_state() == _thread_in_Java) {
470 if (thread->in_stack_reserved_zone(addr)) {
471 frame fr;
472 if (os::Solaris::get_frame_at_stack_banging_point(thread, uc, &fr)) {
473 assert(fr.is_java_frame(), "Must be Java frame");
474 frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
475 if (activation.sp() != NULL) {
476 thread->disable_stack_reserved_zone();
477 if (activation.is_interpreted_frame()) {
478 thread->set_reserved_stack_activation(
479 activation.fp() + frame::interpreter_frame_initial_sp_offset);
480 } else {
481 thread->set_reserved_stack_activation(activation.unextended_sp());
482 }
483 return true;
484 }
485 }
486 }
487 // Throw a stack overflow exception. Guard pages will be reenabled
488 // while unwinding the stack.
489 thread->disable_stack_yellow_zone();
490 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
491 } else {
492 // Thread was in the vm or native code. Return and try to finish.
493 thread->disable_stack_yellow_zone();
494 return true;
495 }
496 } else if (thread->in_stack_red_zone(addr)) {
497 // Fatal red zone violation. Disable the guard pages and fall through
498 // to handle_unexpected_exception way down below.
499 thread->disable_stack_red_zone();
500 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
501 }
502 }
503
504 if ((sig == SIGSEGV) && VM_Version::is_cpuinfo_segv_addr(pc)) {
505 // Verify that OS save/restore AVX registers.
506 stub = VM_Version::cpuinfo_cont_addr();
507 }
508
509 if (thread->thread_state() == _thread_in_vm) {
510 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
511 stub = StubRoutines::handler_for_unsafe_access();
512 }
513 }
514
515 if (thread->thread_state() == _thread_in_Java) {
516 // Support Safepoint Polling
517 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
518 stub = SharedRuntime::get_poll_stub(pc);
519 }
520 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
521 // BugId 4454115: A read from a MappedByteBuffer can fault
522 // here if the underlying file has been truncated.
523 // Do not crash the VM in such a case.
524 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
525 if (cb != NULL) {
526 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
527 if (nm != NULL && nm->has_unsafe_access()) {
528 stub = StubRoutines::handler_for_unsafe_access();
529 }
530 }
531 }
532 else
533 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
534 // integer divide by zero
535 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
536 }
537 #ifndef AMD64
538 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
539 // floating-point divide by zero
540 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
541 }
542 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
543 // The encoding of D2I in i486.ad can cause an exception prior
544 // to the fist instruction if there was an invalid operation
545 // pending. We want to dismiss that exception. From the win_32
546 // side it also seems that if it really was the fist causing
547 // the exception that we do the d2i by hand with different
548 // rounding. Seems kind of weird. QQQ TODO
549 // Note that we take the exception at the NEXT floating point instruction.
550 if (pc[0] == 0xDB) {
551 assert(pc[0] == 0xDB, "not a FIST opcode");
552 assert(pc[1] == 0x14, "not a FIST opcode");
553 assert(pc[2] == 0x24, "not a FIST opcode");
554 return true;
555 } else {
556 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
557 assert(pc[-2] == 0x14, "not an flt invalid opcode");
558 assert(pc[-1] == 0x24, "not an flt invalid opcode");
559 }
560 }
561 else if (sig == SIGFPE ) {
562 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
563 }
564 #endif // !AMD64
565
566 // QQQ It doesn't seem that we need to do this on x86 because we should be able
567 // to return properly from the handler without this extra stuff on the back side.
568
569 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
570 // Determination of interpreter/vtable stub/compiled code null exception
571 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
572 }
573 }
574
575 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
576 // and the heap gets shrunk before the field access.
577 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
578 address addr = JNI_FastGetField::find_slowcase_pc(pc);
579 if (addr != (address)-1) {
580 stub = addr;
581 }
582 }
583
584 // Check to see if we caught the safepoint code in the
585 // process of write protecting the memory serialization page.
586 // It write enables the page immediately after protecting it
587 // so we can just return to retry the write.
588 if ((sig == SIGSEGV) &&
589 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
590 // Block current thread until the memory serialize page permission restored.
591 os::block_on_serialize_page_trap();
592 return true;
593 }
594 }
595
596 // Execution protection violation
597 //
598 // Preventative code for future versions of Solaris which may
599 // enable execution protection when running the 32-bit VM on AMD64.
600 //
601 // This should be kept as the last step in the triage. We don't
602 // have a dedicated trap number for a no-execute fault, so be
603 // conservative and allow other handlers the first shot.
604 //
605 // Note: We don't test that info->si_code == SEGV_ACCERR here.
606 // this si_code is so generic that it is almost meaningless; and
607 // the si_code for this condition may change in the future.
608 // Furthermore, a false-positive should be harmless.
609 if (UnguardOnExecutionViolation > 0 &&
610 (sig == SIGSEGV || sig == SIGBUS) &&
611 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
612 int page_size = os::vm_page_size();
613 address addr = (address) info->si_addr;
614 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
615 // Make sure the pc and the faulting address are sane.
616 //
617 // If an instruction spans a page boundary, and the page containing
618 // the beginning of the instruction is executable but the following
619 // page is not, the pc and the faulting address might be slightly
620 // different - we still want to unguard the 2nd page in this case.
621 //
622 // 15 bytes seems to be a (very) safe value for max instruction size.
623 bool pc_is_near_addr =
624 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
625 bool instr_spans_page_boundary =
626 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
627 (intptr_t) page_size) > 0);
628
629 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
630 static volatile address last_addr =
631 (address) os::non_memory_address_word();
632
633 // In conservative mode, don't unguard unless the address is in the VM
634 if (addr != last_addr &&
635 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
636
637 // Make memory rwx and retry
638 address page_start =
639 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
640 bool res = os::protect_memory((char*) page_start, page_size,
641 os::MEM_PROT_RWX);
642
643 if (PrintMiscellaneous && Verbose) {
644 char buf[256];
645 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
646 "at " INTPTR_FORMAT
647 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
648 page_start, (res ? "success" : "failed"), errno);
649 tty->print_raw_cr(buf);
650 }
651 stub = pc;
652
653 // Set last_addr so if we fault again at the same address, we don't end
654 // up in an endless loop.
655 //
656 // There are two potential complications here. Two threads trapping at
657 // the same address at the same time could cause one of the threads to
658 // think it already unguarded, and abort the VM. Likely very rare.
659 //
660 // The other race involves two threads alternately trapping at
661 // different addresses and failing to unguard the page, resulting in
662 // an endless loop. This condition is probably even more unlikely than
663 // the first.
664 //
665 // Although both cases could be avoided by using locks or thread local
666 // last_addr, these solutions are unnecessary complication: this
667 // handler is a best-effort safety net, not a complete solution. It is
668 // disabled by default and should only be used as a workaround in case
669 // we missed any no-execute-unsafe VM code.
670
671 last_addr = addr;
672 }
673 }
674 }
675
676 if (stub != NULL) {
677 // save all thread context in case we need to restore it
678
679 if (thread != NULL) thread->set_saved_exception_pc(pc);
680 // 12/02/99: On Sparc it appears that the full context is also saved
681 // but as yet, no one looks at or restores that saved context
682 os::Solaris::ucontext_set_pc(uc, stub);
683 return true;
684 }
685
686 // signal-chaining
687 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
688 return true;
689 }
690
691 #ifndef AMD64
692 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
693 // Handle an undefined selector caused by an attempt to assign
694 // fs in libthread getipriptr(). With the current libthread design every 512
695 // thread creations the LDT for a private thread data structure is extended
696 // and thre is a hazard that and another thread attempting a thread creation
697 // will use a stale LDTR that doesn't reflect the structure's growth,
698 // causing a GP fault.
699 // Enforce the probable limit of passes through here to guard against an
700 // infinite loop if some other move to fs caused the GP fault. Note that
701 // this loop counter is ultimately a heuristic as it is possible for
702 // more than one thread to generate this fault at a time in an MP system.
703 // In the case of the loop count being exceeded or if the poll fails
704 // just fall through to a fatal error.
705 // If there is some other source of T_GPFLT traps and the text at EIP is
706 // unreadable this code will loop infinitely until the stack is exausted.
707 // The key to diagnosis in this case is to look for the bottom signal handler
708 // frame.
709
710 if(! IgnoreLibthreadGPFault) {
711 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
712 const unsigned char *p =
713 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
714
715 // Expected instruction?
716
717 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
718
719 Atomic::inc(&ldtr_refresh);
720
721 // Infinite loop?
722
723 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
724
725 // No, force scheduling to get a fresh view of the LDTR
726
727 if(poll(NULL, 0, 10) == 0) {
728
729 // Retry the move
730
731 return false;
732 }
733 }
734 }
735 }
736 }
737 #endif // !AMD64
738
739 if (!abort_if_unrecognized) {
740 // caller wants another chance, so give it to him
741 return false;
742 }
743
744 if (!os::Solaris::libjsig_is_loaded) {
745 struct sigaction oldAct;
746 sigaction(sig, (struct sigaction *)0, &oldAct);
747 if (oldAct.sa_sigaction != signalHandler) {
748 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
749 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
750 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
751 }
752 }
753
754 if (pc == NULL && uc != NULL) {
755 pc = (address) uc->uc_mcontext.gregs[REG_PC];
756 }
757
758 // unmask current signal
759 sigset_t newset;
760 sigemptyset(&newset);
761 sigaddset(&newset, sig);
762 sigprocmask(SIG_UNBLOCK, &newset, NULL);
763
764 // Determine which sort of error to throw. Out of swap may signal
765 // on the thread stack, which could get a mapping error when touched.
766 address addr = (address) info->si_addr;
767 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) {
768 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack.");
769 }
770
771 VMError::report_and_die(t, sig, pc, info, ucVoid);
772
773 ShouldNotReachHere();
774 return false;
775 }
776
777 void os::print_context(outputStream *st, void *context) {
778 if (context == NULL) return;
779
780 ucontext_t *uc = (ucontext_t*)context;
781 st->print_cr("Registers:");
782 #ifdef AMD64
783 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
784 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
785 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
786 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
787 st->cr();
788 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
789 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
790 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
791 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
792 st->cr();
793 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
794 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
795 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
796 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
797 st->cr();
798 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
799 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
800 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
801 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
802 st->cr();
803 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
804 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]);
805 #else
806 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
807 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
808 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
809 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
810 st->cr();
811 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
812 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
813 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
814 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
815 st->cr();
816 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
817 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
818 #endif // AMD64
819 st->cr();
820 st->cr();
821
822 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
823 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
824 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
825 st->cr();
826
827 // Note: it may be unsafe to inspect memory near pc. For example, pc may
828 // point to garbage if entry point in an nmethod is corrupted. Leave
829 // this at the end, and hope for the best.
830 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
831 address pc = epc.pc();
832 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
833 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
834 }
835
836 void os::print_register_info(outputStream *st, void *context) {
837 if (context == NULL) return;
838
839 ucontext_t *uc = (ucontext_t*)context;
840
841 st->print_cr("Register to memory mapping:");
842 st->cr();
843
844 // this is horrendously verbose but the layout of the registers in the
845 // context does not match how we defined our abstract Register set, so
846 // we can't just iterate through the gregs area
847
848 // this is only for the "general purpose" registers
849
850 #ifdef AMD64
851 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
852 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
853 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
854 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
855 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
856 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]);
857 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
858 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
859 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]);
860 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]);
861 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]);
862 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]);
863 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]);
864 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]);
865 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]);
866 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]);
867 #else
868 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]);
869 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]);
870 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]);
871 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]);
872 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]);
873 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]);
874 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]);
875 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]);
876 #endif
877
878 st->cr();
879 }
880
881
882 #ifdef AMD64
883 void os::Solaris::init_thread_fpu_state(void) {
884 // Nothing to do
885 }
886 #else
887 // From solaris_i486.s
888 extern "C" void fixcw();
889
890 void os::Solaris::init_thread_fpu_state(void) {
891 // Set fpu to 53 bit precision. This happens too early to use a stub.
892 fixcw();
893 }
894
895 // These routines are the initial value of atomic_xchg_entry(),
896 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
897 // until initialization is complete.
898 // TODO - replace with .il implementation when compiler supports it.
899
900 typedef jint xchg_func_t (jint, volatile jint*);
901 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
902 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
903 typedef jint add_func_t (jint, volatile jint*);
904
905 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
906 // try to use the stub:
907 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
908
909 if (func != NULL) {
910 os::atomic_xchg_func = func;
911 return (*func)(exchange_value, dest);
912 }
913 assert(Threads::number_of_threads() == 0, "for bootstrap only");
914
915 jint old_value = *dest;
916 *dest = exchange_value;
917 return old_value;
918 }
919
920 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
921 // try to use the stub:
922 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
923
924 if (func != NULL) {
925 os::atomic_cmpxchg_func = func;
926 return (*func)(exchange_value, dest, compare_value);
927 }
928 assert(Threads::number_of_threads() == 0, "for bootstrap only");
929
930 jint old_value = *dest;
931 if (old_value == compare_value)
932 *dest = exchange_value;
933 return old_value;
934 }
935
936 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
937 // try to use the stub:
938 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
939
940 if (func != NULL) {
941 os::atomic_cmpxchg_long_func = func;
942 return (*func)(exchange_value, dest, compare_value);
943 }
944 assert(Threads::number_of_threads() == 0, "for bootstrap only");
945
946 jlong old_value = *dest;
947 if (old_value == compare_value)
948 *dest = exchange_value;
949 return old_value;
950 }
951
952 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
953 // try to use the stub:
954 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
955
956 if (func != NULL) {
957 os::atomic_add_func = func;
958 return (*func)(add_value, dest);
959 }
960 assert(Threads::number_of_threads() == 0, "for bootstrap only");
961
962 return (*dest) += add_value;
963 }
964
965 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
966 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
967 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
968 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
969
970 extern "C" void _solaris_raw_setup_fpu(address ptr);
971 void os::setup_fpu() {
972 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
973 _solaris_raw_setup_fpu(fpu_cntrl);
974 }
975 #endif // AMD64
976
977 #ifndef PRODUCT
978 void os::verify_stack_alignment() {
979 #ifdef AMD64
980 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
981 #endif
982 }
983 #endif
984
985 int os::extra_bang_size_in_bytes() {
986 // JDK-8050147 requires the full cache line bang for x86.
987 return VM_Version::L1_line_size();
988 }