comparison src/os_cpu/solaris_x86/vm/os_solaris_x86.cpp @ 0:a61af66fc99e jdk7-b24

Initial load
author duke
date Sat, 01 Dec 2007 00:00:00 +0000
parents
children 93b6525e3b82
comparison
equal deleted inserted replaced
-1:000000000000 0:a61af66fc99e
1 /*
2 * Copyright 1999-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 // do not include precompiled header file
26 # include "incls/_os_solaris_x86.cpp.incl"
27
28 // put OS-includes here
29 # include <sys/types.h>
30 # include <sys/mman.h>
31 # include <pthread.h>
32 # include <signal.h>
33 # include <setjmp.h>
34 # include <errno.h>
35 # include <dlfcn.h>
36 # include <stdio.h>
37 # include <unistd.h>
38 # include <sys/resource.h>
39 # include <thread.h>
40 # include <sys/stat.h>
41 # include <sys/time.h>
42 # include <sys/filio.h>
43 # include <sys/utsname.h>
44 # include <sys/systeminfo.h>
45 # include <sys/socket.h>
46 # include <sys/trap.h>
47 # include <sys/lwp.h>
48 # include <pwd.h>
49 # include <poll.h>
50 # include <sys/lwp.h>
51 # include <procfs.h> // see comment in <sys/procfs.h>
52
53 #ifndef AMD64
54 // QQQ seems useless at this point
55 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
56 #endif // AMD64
57 # include <sys/procfs.h> // see comment in <sys/procfs.h>
58
59
60 #define MAX_PATH (2 * K)
61
62 // Minimum stack size for the VM. It's easier to document a constant value
63 // but it's different for x86 and sparc because the page sizes are different.
64 #ifdef AMD64
65 size_t os::Solaris::min_stack_allowed = 224*K;
66 #define REG_SP REG_RSP
67 #define REG_PC REG_RIP
68 #define REG_FP REG_RBP
69 #else
70 size_t os::Solaris::min_stack_allowed = 64*K;
71 #define REG_SP UESP
72 #define REG_PC EIP
73 #define REG_FP EBP
74 // 4900493 counter to prevent runaway LDTR refresh attempt
75
76 static volatile int ldtr_refresh = 0;
77 // the libthread instruction that faults because of the stale LDTR
78
79 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
80 };
81 #endif // AMD64
82
83 char* os::non_memory_address_word() {
84 // Must never look like an address returned by reserve_memory,
85 // even in its subfields (as defined by the CPU immediate fields,
86 // if the CPU splits constants across multiple instructions).
87 return (char*) -1;
88 }
89
90 //
91 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
92 // There are issues with libthread giving out uc_links for different threads
93 // on the same uc_link chain and bad or circular links.
94 //
95 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
96 if (valid >= suspect ||
97 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
98 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
99 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
100 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
101 return false;
102 }
103
104 if (thread->is_Java_thread()) {
105 if (!valid_stack_address(thread, (address)suspect)) {
106 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
107 return false;
108 }
109 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
110 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
111 return false;
112 }
113 }
114 return true;
115 }
116
117 // We will only follow one level of uc_link since there are libthread
118 // issues with ucontext linking and it is better to be safe and just
119 // let caller retry later.
120 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
121 ucontext_t *uc) {
122
123 ucontext_t *retuc = NULL;
124
125 if (uc != NULL) {
126 if (uc->uc_link == NULL) {
127 // cannot validate without uc_link so accept current ucontext
128 retuc = uc;
129 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
130 // first ucontext is valid so try the next one
131 uc = uc->uc_link;
132 if (uc->uc_link == NULL) {
133 // cannot validate without uc_link so accept current ucontext
134 retuc = uc;
135 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
136 // the ucontext one level down is also valid so return it
137 retuc = uc;
138 }
139 }
140 }
141 return retuc;
142 }
143
144 // Assumes ucontext is valid
145 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
146 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
147 }
148
149 // Assumes ucontext is valid
150 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
151 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
152 }
153
154 // Assumes ucontext is valid
155 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
156 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
157 }
158
159 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
160 // is currently interrupted by SIGPROF.
161 //
162 // The difference between this and os::fetch_frame_from_context() is that
163 // here we try to skip nested signal frames.
164 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
165 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
166
167 assert(thread != NULL, "just checking");
168 assert(ret_sp != NULL, "just checking");
169 assert(ret_fp != NULL, "just checking");
170
171 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
172 return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
173 }
174
175 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
176 intptr_t** ret_sp, intptr_t** ret_fp) {
177
178 ExtendedPC epc;
179 ucontext_t *uc = (ucontext_t*)ucVoid;
180
181 if (uc != NULL) {
182 epc = os::Solaris::ucontext_get_ExtendedPC(uc);
183 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
184 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc);
185 } else {
186 // construct empty ExtendedPC for return value checking
187 epc = ExtendedPC(NULL);
188 if (ret_sp) *ret_sp = (intptr_t *)NULL;
189 if (ret_fp) *ret_fp = (intptr_t *)NULL;
190 }
191
192 return epc;
193 }
194
195 frame os::fetch_frame_from_context(void* ucVoid) {
196 intptr_t* sp;
197 intptr_t* fp;
198 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
199 return frame(sp, fp, epc.pc());
200 }
201
202 frame os::get_sender_for_C_frame(frame* fr) {
203 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
204 }
205
206 extern "C" intptr_t *_get_previous_fp(); // in .il file.
207
208 frame os::current_frame() {
209 intptr_t* fp = _get_previous_fp();
210 frame myframe((intptr_t*)os::current_stack_pointer(),
211 (intptr_t*)fp,
212 CAST_FROM_FN_PTR(address, os::current_frame));
213 if (os::is_first_C_frame(&myframe)) {
214 // stack is not walkable
215 return frame(NULL, NULL, NULL);
216 } else {
217 return os::get_sender_for_C_frame(&myframe);
218 }
219 }
220
221 // This is a simple callback that just fetches a PC for an interrupted thread.
222 // The thread need not be suspended and the fetched PC is just a hint.
223 // This one is currently used for profiling the VMThread ONLY!
224
225 // Must be synchronous
226 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {
227 Thread* thread = args->thread();
228 ucontext_t* uc = args->ucontext();
229 intptr_t* sp;
230
231 assert(ProfileVM && thread->is_VM_thread(), "just checking");
232
233 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);
234 _addr = new_addr;
235 }
236
237 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
238 char lwpstatusfile[PROCFILE_LENGTH];
239 int lwpfd, err;
240
241 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
242 return (err);
243 if (*flags == TRS_LWPID) {
244 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
245 *lwp);
246 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
247 perror("thr_mutator_status: open lwpstatus");
248 return (EINVAL);
249 }
250 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
251 sizeof (lwpstatus_t)) {
252 perror("thr_mutator_status: read lwpstatus");
253 (void) close(lwpfd);
254 return (EINVAL);
255 }
256 (void) close(lwpfd);
257 }
258 return (0);
259 }
260
261 #ifndef AMD64
262
263 // Detecting SSE support by OS
264 // From solaris_i486.s
265 extern "C" bool sse_check();
266 extern "C" bool sse_unavailable();
267
268 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
269 static int sse_status = SSE_UNKNOWN;
270
271
272 static void check_for_sse_support() {
273 if (!VM_Version::supports_sse()) {
274 sse_status = SSE_NOT_SUPPORTED;
275 return;
276 }
277 // looking for _sse_hw in libc.so, if it does not exist or
278 // the value (int) is 0, OS has no support for SSE
279 int *sse_hwp;
280 void *h;
281
282 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
283 //open failed, presume no support for SSE
284 sse_status = SSE_NOT_SUPPORTED;
285 return;
286 }
287 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
288 sse_status = SSE_NOT_SUPPORTED;
289 } else if (*sse_hwp == 0) {
290 sse_status = SSE_NOT_SUPPORTED;
291 }
292 dlclose(h);
293
294 if (sse_status == SSE_UNKNOWN) {
295 bool (*try_sse)() = (bool (*)())sse_check;
296 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
297 }
298
299 }
300
301 bool os::supports_sse() {
302 if (sse_status == SSE_UNKNOWN)
303 check_for_sse_support();
304 return sse_status == SSE_SUPPORTED;
305 }
306
307 #endif // AMD64
308
309 bool os::is_allocatable(size_t bytes) {
310 #ifdef AMD64
311 return true;
312 #else
313
314 if (bytes < 2 * G) {
315 return true;
316 }
317
318 char* addr = reserve_memory(bytes, NULL);
319
320 if (addr != NULL) {
321 release_memory(addr, bytes);
322 }
323
324 return addr != NULL;
325 #endif // AMD64
326
327 }
328
329 extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
330
331 extern "C" void Fetch32PFI () ;
332 extern "C" void Fetch32Resume () ;
333 #ifdef AMD64
334 extern "C" void FetchNPFI () ;
335 extern "C" void FetchNResume () ;
336 #endif // AMD64
337
338 int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {
339 ucontext_t* uc = (ucontext_t*) ucVoid;
340
341 #ifndef AMD64
342 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
343 // the SSE instruction faulted. supports_sse() need return false.
344 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
345 return true;
346 }
347 #endif // !AMD64
348
349 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
350
351 SignalHandlerMark shm(t);
352
353 if(sig == SIGPIPE || sig == SIGXFSZ) {
354 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
355 return true;
356 } else {
357 if (PrintMiscellaneous && (WizardMode || Verbose)) {
358 char buf[64];
359 warning("Ignoring %s - see 4229104 or 6499219",
360 os::exception_name(sig, buf, sizeof(buf)));
361
362 }
363 return true;
364 }
365 }
366
367 JavaThread* thread = NULL;
368 VMThread* vmthread = NULL;
369
370 if (os::Solaris::signal_handlers_are_installed) {
371 if (t != NULL ){
372 if(t->is_Java_thread()) {
373 thread = (JavaThread*)t;
374 }
375 else if(t->is_VM_thread()){
376 vmthread = (VMThread *)t;
377 }
378 }
379 }
380
381 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
382
383 if (sig == os::Solaris::SIGasync()) {
384 if(thread){
385 OSThread::InterruptArguments args(thread, uc);
386 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
387 return true;
388 }
389 else if(vmthread){
390 OSThread::InterruptArguments args(vmthread, uc);
391 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
392 return true;
393 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
394 return true;
395 } else {
396 // If os::Solaris::SIGasync not chained, and this is a non-vm and
397 // non-java thread
398 return true;
399 }
400 }
401
402 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
403 // can't decode this kind of signal
404 info = NULL;
405 } else {
406 assert(sig == info->si_signo, "bad siginfo");
407 }
408
409 // decide if this trap can be handled by a stub
410 address stub = NULL;
411
412 address pc = NULL;
413
414 //%note os_trap_1
415 if (info != NULL && uc != NULL && thread != NULL) {
416 // factor me: getPCfromContext
417 pc = (address) uc->uc_mcontext.gregs[REG_PC];
418
419 // SafeFetch32() support
420 if (pc == (address) Fetch32PFI) {
421 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
422 return true ;
423 }
424 #ifdef AMD64
425 if (pc == (address) FetchNPFI) {
426 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ;
427 return true ;
428 }
429 #endif // AMD64
430
431 // Handle ALL stack overflow variations here
432 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
433 address addr = (address) info->si_addr;
434 if (thread->in_stack_yellow_zone(addr)) {
435 thread->disable_stack_yellow_zone();
436 if (thread->thread_state() == _thread_in_Java) {
437 // Throw a stack overflow exception. Guard pages will be reenabled
438 // while unwinding the stack.
439 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
440 } else {
441 // Thread was in the vm or native code. Return and try to finish.
442 return true;
443 }
444 } else if (thread->in_stack_red_zone(addr)) {
445 // Fatal red zone violation. Disable the guard pages and fall through
446 // to handle_unexpected_exception way down below.
447 thread->disable_stack_red_zone();
448 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
449 }
450 }
451
452 if (thread->thread_state() == _thread_in_vm) {
453 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
454 stub = StubRoutines::handler_for_unsafe_access();
455 }
456 }
457
458 if (thread->thread_state() == _thread_in_Java) {
459 // Support Safepoint Polling
460 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
461 stub = SharedRuntime::get_poll_stub(pc);
462 }
463 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
464 // BugId 4454115: A read from a MappedByteBuffer can fault
465 // here if the underlying file has been truncated.
466 // Do not crash the VM in such a case.
467 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
468 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
469 if (nm != NULL && nm->has_unsafe_access()) {
470 stub = StubRoutines::handler_for_unsafe_access();
471 }
472 }
473 else
474 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
475 // integer divide by zero
476 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
477 }
478 #ifndef AMD64
479 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
480 // floating-point divide by zero
481 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
482 }
483 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
484 // The encoding of D2I in i486.ad can cause an exception prior
485 // to the fist instruction if there was an invalid operation
486 // pending. We want to dismiss that exception. From the win_32
487 // side it also seems that if it really was the fist causing
488 // the exception that we do the d2i by hand with different
489 // rounding. Seems kind of weird. QQQ TODO
490 // Note that we take the exception at the NEXT floating point instruction.
491 if (pc[0] == 0xDB) {
492 assert(pc[0] == 0xDB, "not a FIST opcode");
493 assert(pc[1] == 0x14, "not a FIST opcode");
494 assert(pc[2] == 0x24, "not a FIST opcode");
495 return true;
496 } else {
497 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
498 assert(pc[-2] == 0x14, "not an flt invalid opcode");
499 assert(pc[-1] == 0x24, "not an flt invalid opcode");
500 }
501 }
502 else if (sig == SIGFPE ) {
503 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
504 }
505 #endif // !AMD64
506
507 // QQQ It doesn't seem that we need to do this on x86 because we should be able
508 // to return properly from the handler without this extra stuff on the back side.
509
510 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
511 // Determination of interpreter/vtable stub/compiled code null exception
512 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
513 }
514 }
515
516 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
517 // and the heap gets shrunk before the field access.
518 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
519 address addr = JNI_FastGetField::find_slowcase_pc(pc);
520 if (addr != (address)-1) {
521 stub = addr;
522 }
523 }
524
525 // Check to see if we caught the safepoint code in the
526 // process of write protecting the memory serialization page.
527 // It write enables the page immediately after protecting it
528 // so we can just return to retry the write.
529 if ((sig == SIGSEGV) &&
530 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
531 // Block current thread until the memory serialize page permission restored.
532 os::block_on_serialize_page_trap();
533 return true;
534 }
535 }
536
537 // Execution protection violation
538 //
539 // Preventative code for future versions of Solaris which may
540 // enable execution protection when running the 32-bit VM on AMD64.
541 //
542 // This should be kept as the last step in the triage. We don't
543 // have a dedicated trap number for a no-execute fault, so be
544 // conservative and allow other handlers the first shot.
545 //
546 // Note: We don't test that info->si_code == SEGV_ACCERR here.
547 // this si_code is so generic that it is almost meaningless; and
548 // the si_code for this condition may change in the future.
549 // Furthermore, a false-positive should be harmless.
550 if (UnguardOnExecutionViolation > 0 &&
551 (sig == SIGSEGV || sig == SIGBUS) &&
552 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
553 int page_size = os::vm_page_size();
554 address addr = (address) info->si_addr;
555 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
556 // Make sure the pc and the faulting address are sane.
557 //
558 // If an instruction spans a page boundary, and the page containing
559 // the beginning of the instruction is executable but the following
560 // page is not, the pc and the faulting address might be slightly
561 // different - we still want to unguard the 2nd page in this case.
562 //
563 // 15 bytes seems to be a (very) safe value for max instruction size.
564 bool pc_is_near_addr =
565 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
566 bool instr_spans_page_boundary =
567 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
568 (intptr_t) page_size) > 0);
569
570 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
571 static volatile address last_addr =
572 (address) os::non_memory_address_word();
573
574 // In conservative mode, don't unguard unless the address is in the VM
575 if (addr != last_addr &&
576 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
577
578 // Unguard and retry
579 address page_start =
580 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
581 bool res = os::unguard_memory((char*) page_start, page_size);
582
583 if (PrintMiscellaneous && Verbose) {
584 char buf[256];
585 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
586 "at " INTPTR_FORMAT
587 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
588 page_start, (res ? "success" : "failed"), errno);
589 tty->print_raw_cr(buf);
590 }
591 stub = pc;
592
593 // Set last_addr so if we fault again at the same address, we don't end
594 // up in an endless loop.
595 //
596 // There are two potential complications here. Two threads trapping at
597 // the same address at the same time could cause one of the threads to
598 // think it already unguarded, and abort the VM. Likely very rare.
599 //
600 // The other race involves two threads alternately trapping at
601 // different addresses and failing to unguard the page, resulting in
602 // an endless loop. This condition is probably even more unlikely than
603 // the first.
604 //
605 // Although both cases could be avoided by using locks or thread local
606 // last_addr, these solutions are unnecessary complication: this
607 // handler is a best-effort safety net, not a complete solution. It is
608 // disabled by default and should only be used as a workaround in case
609 // we missed any no-execute-unsafe VM code.
610
611 last_addr = addr;
612 }
613 }
614 }
615
616 if (stub != NULL) {
617 // save all thread context in case we need to restore it
618
619 if (thread != NULL) thread->set_saved_exception_pc(pc);
620 // 12/02/99: On Sparc it appears that the full context is also saved
621 // but as yet, no one looks at or restores that saved context
622 // factor me: setPC
623 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub;
624 return true;
625 }
626
627 // signal-chaining
628 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
629 return true;
630 }
631
632 #ifndef AMD64
633 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
634 // Handle an undefined selector caused by an attempt to assign
635 // fs in libthread getipriptr(). With the current libthread design every 512
636 // thread creations the LDT for a private thread data structure is extended
637 // and thre is a hazard that and another thread attempting a thread creation
638 // will use a stale LDTR that doesn't reflect the structure's growth,
639 // causing a GP fault.
640 // Enforce the probable limit of passes through here to guard against an
641 // infinite loop if some other move to fs caused the GP fault. Note that
642 // this loop counter is ultimately a heuristic as it is possible for
643 // more than one thread to generate this fault at a time in an MP system.
644 // In the case of the loop count being exceeded or if the poll fails
645 // just fall through to a fatal error.
646 // If there is some other source of T_GPFLT traps and the text at EIP is
647 // unreadable this code will loop infinitely until the stack is exausted.
648 // The key to diagnosis in this case is to look for the bottom signal handler
649 // frame.
650
651 if(! IgnoreLibthreadGPFault) {
652 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
653 const unsigned char *p =
654 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
655
656 // Expected instruction?
657
658 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
659
660 Atomic::inc(&ldtr_refresh);
661
662 // Infinite loop?
663
664 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
665
666 // No, force scheduling to get a fresh view of the LDTR
667
668 if(poll(NULL, 0, 10) == 0) {
669
670 // Retry the move
671
672 return false;
673 }
674 }
675 }
676 }
677 }
678 #endif // !AMD64
679
680 if (!abort_if_unrecognized) {
681 // caller wants another chance, so give it to him
682 return false;
683 }
684
685 if (!os::Solaris::libjsig_is_loaded) {
686 struct sigaction oldAct;
687 sigaction(sig, (struct sigaction *)0, &oldAct);
688 if (oldAct.sa_sigaction != signalHandler) {
689 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
690 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
691 warning("Unexpected Signal %d occured under user-defined signal handler %#lx", sig, (long)sighand);
692 }
693 }
694
695 if (pc == NULL && uc != NULL) {
696 pc = (address) uc->uc_mcontext.gregs[REG_PC];
697 }
698
699 // unmask current signal
700 sigset_t newset;
701 sigemptyset(&newset);
702 sigaddset(&newset, sig);
703 sigprocmask(SIG_UNBLOCK, &newset, NULL);
704
705 VMError err(t, sig, pc, info, ucVoid);
706 err.report_and_die();
707
708 ShouldNotReachHere();
709 }
710
711 void os::print_context(outputStream *st, void *context) {
712 if (context == NULL) return;
713
714 ucontext_t *uc = (ucontext_t*)context;
715 st->print_cr("Registers:");
716 #ifdef AMD64
717 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
718 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
719 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
720 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
721 st->cr();
722 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
723 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
724 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
725 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
726 st->cr();
727 st->print(", R8=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
728 st->print(", R9=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
729 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
730 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
731 st->print(", R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
732 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
733 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
734 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
735 st->cr();
736 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
737 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]);
738 #else
739 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
740 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
741 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
742 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
743 st->cr();
744 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
745 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
746 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
747 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
748 st->cr();
749 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
750 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
751 #endif // AMD64
752 st->cr();
753 st->cr();
754
755 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
756 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
757 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
758 st->cr();
759
760 // Note: it may be unsafe to inspect memory near pc. For example, pc may
761 // point to garbage if entry point in an nmethod is corrupted. Leave
762 // this at the end, and hope for the best.
763 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
764 address pc = epc.pc();
765 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
766 print_hex_dump(st, pc - 16, pc + 16, sizeof(char));
767 }
768
769 #ifdef AMD64
770 void os::Solaris::init_thread_fpu_state(void) {
771 // Nothing to do
772 }
773 #else
774 // From solaris_i486.s
775 extern "C" void fixcw();
776
777 void os::Solaris::init_thread_fpu_state(void) {
778 // Set fpu to 53 bit precision. This happens too early to use a stub.
779 fixcw();
780 }
781
782 // These routines are the initial value of atomic_xchg_entry(),
783 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
784 // until initialization is complete.
785 // TODO - replace with .il implementation when compiler supports it.
786
787 typedef jint xchg_func_t (jint, volatile jint*);
788 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
789 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
790 typedef jint add_func_t (jint, volatile jint*);
791 typedef void fence_func_t ();
792
793 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
794 // try to use the stub:
795 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
796
797 if (func != NULL) {
798 os::atomic_xchg_func = func;
799 return (*func)(exchange_value, dest);
800 }
801 assert(Threads::number_of_threads() == 0, "for bootstrap only");
802
803 jint old_value = *dest;
804 *dest = exchange_value;
805 return old_value;
806 }
807
808 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
809 // try to use the stub:
810 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
811
812 if (func != NULL) {
813 os::atomic_cmpxchg_func = func;
814 return (*func)(exchange_value, dest, compare_value);
815 }
816 assert(Threads::number_of_threads() == 0, "for bootstrap only");
817
818 jint old_value = *dest;
819 if (old_value == compare_value)
820 *dest = exchange_value;
821 return old_value;
822 }
823
824 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
825 // try to use the stub:
826 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
827
828 if (func != NULL) {
829 os::atomic_cmpxchg_long_func = func;
830 return (*func)(exchange_value, dest, compare_value);
831 }
832 assert(Threads::number_of_threads() == 0, "for bootstrap only");
833
834 jlong old_value = *dest;
835 if (old_value == compare_value)
836 *dest = exchange_value;
837 return old_value;
838 }
839
840 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
841 // try to use the stub:
842 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
843
844 if (func != NULL) {
845 os::atomic_add_func = func;
846 return (*func)(add_value, dest);
847 }
848 assert(Threads::number_of_threads() == 0, "for bootstrap only");
849
850 return (*dest) += add_value;
851 }
852
853 void os::fence_bootstrap() {
854 // try to use the stub:
855 fence_func_t* func = CAST_TO_FN_PTR(fence_func_t*, StubRoutines::fence_entry());
856
857 if (func != NULL) {
858 os::fence_func = func;
859 (*func)();
860 return;
861 }
862 assert(Threads::number_of_threads() == 0, "for bootstrap only");
863
864 // don't have to do anything for a single thread
865 }
866
867 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
868 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
869 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
870 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
871 fence_func_t* os::fence_func = os::fence_bootstrap;
872
873 extern "C" _solaris_raw_setup_fpu(address ptr);
874 void os::setup_fpu() {
875 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
876 _solaris_raw_setup_fpu(fpu_cntrl);
877 }
878 #endif // AMD64