1 /*
2 * Copyright (c) 1999, 2010, 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 #include "precompiled.hpp"
26 #include "assembler_x86.inline.hpp"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "jvm_solaris.h"
34 #include "memory/allocation.inline.hpp"
35 #include "mutex_solaris.inline.hpp"
36 #include "nativeInst_x86.hpp"
37 #include "os_share_solaris.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/hpi.hpp"
45 #include "runtime/interfaceSupport.hpp"
46 #include "runtime/java.hpp"
47 #include "runtime/javaCalls.hpp"
48 #include "runtime/mutexLocker.hpp"
49 #include "runtime/osThread.hpp"
50 #include "runtime/sharedRuntime.hpp"
51 #include "runtime/stubRoutines.hpp"
52 #include "runtime/timer.hpp"
53 #include "thread_solaris.inline.hpp"
54 #include "utilities/events.hpp"
55 #include "utilities/vmError.hpp"
56 #ifdef COMPILER1
57 #include "c1/c1_Runtime1.hpp"
58 #endif
59 #ifdef COMPILER2
60 #include "opto/runtime.hpp"
61 #endif
62
63 // do not include precompiled header file
64 // put OS-includes here
65 # include <sys/types.h>
66 # include <sys/mman.h>
67 # include <pthread.h>
68 # include <signal.h>
69 # include <setjmp.h>
70 # include <errno.h>
71 # include <dlfcn.h>
72 # include <stdio.h>
73 # include <unistd.h>
74 # include <sys/resource.h>
75 # include <thread.h>
76 # include <sys/stat.h>
77 # include <sys/time.h>
78 # include <sys/filio.h>
79 # include <sys/utsname.h>
80 # include <sys/systeminfo.h>
81 # include <sys/socket.h>
82 # include <sys/trap.h>
83 # include <sys/lwp.h>
84 # include <pwd.h>
85 # include <poll.h>
86 # include <sys/lwp.h>
87 # include <procfs.h> // see comment in <sys/procfs.h>
88
89 #ifndef AMD64
90 // QQQ seems useless at this point
91 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
92 #endif // AMD64
93 # include <sys/procfs.h> // see comment in <sys/procfs.h>
94
95
96 #define MAX_PATH (2 * K)
97
98 // Minimum stack size for the VM. It's easier to document a constant value
99 // but it's different for x86 and sparc because the page sizes are different.
100 #ifdef AMD64
101 size_t os::Solaris::min_stack_allowed = 224*K;
102 #define REG_SP REG_RSP
103 #define REG_PC REG_RIP
104 #define REG_FP REG_RBP
105 #else
106 size_t os::Solaris::min_stack_allowed = 64*K;
107 #define REG_SP UESP
108 #define REG_PC EIP
109 #define REG_FP EBP
110 // 4900493 counter to prevent runaway LDTR refresh attempt
111
112 static volatile int ldtr_refresh = 0;
113 // the libthread instruction that faults because of the stale LDTR
114
115 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
116 };
117 #endif // AMD64
118
119 char* os::non_memory_address_word() {
120 // Must never look like an address returned by reserve_memory,
121 // even in its subfields (as defined by the CPU immediate fields,
122 // if the CPU splits constants across multiple instructions).
123 return (char*) -1;
124 }
125
126 //
127 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
128 // There are issues with libthread giving out uc_links for different threads
129 // on the same uc_link chain and bad or circular links.
130 //
131 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
132 if (valid >= suspect ||
133 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
134 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
135 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
136 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
137 return false;
138 }
139
140 if (thread->is_Java_thread()) {
141 if (!valid_stack_address(thread, (address)suspect)) {
142 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
143 return false;
144 }
145 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
146 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
147 return false;
148 }
149 }
150 return true;
151 }
152
153 // We will only follow one level of uc_link since there are libthread
154 // issues with ucontext linking and it is better to be safe and just
155 // let caller retry later.
156 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
157 ucontext_t *uc) {
158
159 ucontext_t *retuc = NULL;
160
161 if (uc != NULL) {
162 if (uc->uc_link == NULL) {
163 // cannot validate without uc_link so accept current ucontext
164 retuc = uc;
165 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
166 // first ucontext is valid so try the next one
167 uc = uc->uc_link;
168 if (uc->uc_link == NULL) {
169 // cannot validate without uc_link so accept current ucontext
170 retuc = uc;
171 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
172 // the ucontext one level down is also valid so return it
173 retuc = uc;
174 }
175 }
176 }
177 return retuc;
178 }
179
180 // Assumes ucontext is valid
181 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
182 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
183 }
184
185 // Assumes ucontext is valid
186 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
187 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
188 }
189
190 // Assumes ucontext is valid
191 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
192 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
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::get_sender_for_C_frame(frame* fr) {
239 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
240 }
241
242 extern "C" intptr_t *_get_current_fp(); // in .il file
243
244 frame os::current_frame() {
245 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
246 frame myframe((intptr_t*)os::current_stack_pointer(),
247 (intptr_t*)fp,
248 CAST_FROM_FN_PTR(address, os::current_frame));
249 if (os::is_first_C_frame(&myframe)) {
250 // stack is not walkable
251 frame ret; // This will be a null useless frame
252 return ret;
253 } else {
254 return os::get_sender_for_C_frame(&myframe);
255 }
256 }
257
258 // This is a simple callback that just fetches a PC for an interrupted thread.
259 // The thread need not be suspended and the fetched PC is just a hint.
260 // This one is currently used for profiling the VMThread ONLY!
261
262 // Must be synchronous
263 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {
264 Thread* thread = args->thread();
265 ucontext_t* uc = args->ucontext();
266 intptr_t* sp;
267
268 assert(ProfileVM && thread->is_VM_thread(), "just checking");
269
270 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);
271 _addr = new_addr;
272 }
273
274 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
275 char lwpstatusfile[PROCFILE_LENGTH];
276 int lwpfd, err;
277
278 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
279 return (err);
280 if (*flags == TRS_LWPID) {
281 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
282 *lwp);
283 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
284 perror("thr_mutator_status: open lwpstatus");
285 return (EINVAL);
286 }
287 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
288 sizeof (lwpstatus_t)) {
289 perror("thr_mutator_status: read lwpstatus");
290 (void) close(lwpfd);
291 return (EINVAL);
292 }
293 (void) close(lwpfd);
294 }
295 return (0);
296 }
297
298 #ifndef AMD64
299
300 // Detecting SSE support by OS
301 // From solaris_i486.s
302 extern "C" bool sse_check();
303 extern "C" bool sse_unavailable();
304
305 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
306 static int sse_status = SSE_UNKNOWN;
307
308
309 static void check_for_sse_support() {
310 if (!VM_Version::supports_sse()) {
311 sse_status = SSE_NOT_SUPPORTED;
312 return;
313 }
314 // looking for _sse_hw in libc.so, if it does not exist or
315 // the value (int) is 0, OS has no support for SSE
316 int *sse_hwp;
317 void *h;
318
319 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
320 //open failed, presume no support for SSE
321 sse_status = SSE_NOT_SUPPORTED;
322 return;
323 }
324 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
325 sse_status = SSE_NOT_SUPPORTED;
326 } else if (*sse_hwp == 0) {
327 sse_status = SSE_NOT_SUPPORTED;
328 }
329 dlclose(h);
330
331 if (sse_status == SSE_UNKNOWN) {
332 bool (*try_sse)() = (bool (*)())sse_check;
333 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
334 }
335
336 }
337
338 #endif // AMD64
339
340 bool os::supports_sse() {
341 #ifdef AMD64
342 return true;
343 #else
344 if (sse_status == SSE_UNKNOWN)
345 check_for_sse_support();
346 return sse_status == SSE_SUPPORTED;
347 #endif // AMD64
348 }
349
350 bool os::is_allocatable(size_t bytes) {
351 #ifdef AMD64
352 return true;
353 #else
354
355 if (bytes < 2 * G) {
356 return true;
357 }
358
359 char* addr = reserve_memory(bytes, NULL);
360
361 if (addr != NULL) {
362 release_memory(addr, bytes);
363 }
364
365 return addr != NULL;
366 #endif // AMD64
367
368 }
369
370 extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
371
372 extern "C" void Fetch32PFI () ;
373 extern "C" void Fetch32Resume () ;
374 #ifdef AMD64
375 extern "C" void FetchNPFI () ;
376 extern "C" void FetchNResume () ;
377 #endif // AMD64
378
379 int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {
380 ucontext_t* uc = (ucontext_t*) ucVoid;
381
382 #ifndef AMD64
383 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
384 // the SSE instruction faulted. supports_sse() need return false.
385 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
386 return true;
387 }
388 #endif // !AMD64
389
390 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
391
392 SignalHandlerMark shm(t);
393
394 if(sig == SIGPIPE || sig == SIGXFSZ) {
395 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
396 return true;
397 } else {
398 if (PrintMiscellaneous && (WizardMode || Verbose)) {
399 char buf[64];
400 warning("Ignoring %s - see 4229104 or 6499219",
401 os::exception_name(sig, buf, sizeof(buf)));
402
403 }
404 return true;
405 }
406 }
407
408 JavaThread* thread = NULL;
409 VMThread* vmthread = NULL;
410
411 if (os::Solaris::signal_handlers_are_installed) {
412 if (t != NULL ){
413 if(t->is_Java_thread()) {
414 thread = (JavaThread*)t;
415 }
416 else if(t->is_VM_thread()){
417 vmthread = (VMThread *)t;
418 }
419 }
420 }
421
422 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
423
424 if (sig == os::Solaris::SIGasync()) {
425 if(thread){
426 OSThread::InterruptArguments args(thread, uc);
427 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
428 return true;
429 }
430 else if(vmthread){
431 OSThread::InterruptArguments args(vmthread, uc);
432 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
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 // SafeFetch32() support
461 if (pc == (address) Fetch32PFI) {
462 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
463 return true ;
464 }
465 #ifdef AMD64
466 if (pc == (address) FetchNPFI) {
467 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ;
468 return true ;
469 }
470 #endif // AMD64
471
472 // Handle ALL stack overflow variations here
473 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
474 address addr = (address) info->si_addr;
475 if (thread->in_stack_yellow_zone(addr)) {
476 thread->disable_stack_yellow_zone();
477 if (thread->thread_state() == _thread_in_Java) {
478 // Throw a stack overflow exception. Guard pages will be reenabled
479 // while unwinding the stack.
480 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
481 } else {
482 // Thread was in the vm or native code. Return and try to finish.
483 return true;
484 }
485 } else if (thread->in_stack_red_zone(addr)) {
486 // Fatal red zone violation. Disable the guard pages and fall through
487 // to handle_unexpected_exception way down below.
488 thread->disable_stack_red_zone();
489 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
490 }
491 }
492
493 if (thread->thread_state() == _thread_in_vm) {
494 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
495 stub = StubRoutines::handler_for_unsafe_access();
496 }
497 }
498
499 if (thread->thread_state() == _thread_in_Java) {
500 // Support Safepoint Polling
501 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
502 stub = SharedRuntime::get_poll_stub(pc);
503 }
504 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
505 // BugId 4454115: A read from a MappedByteBuffer can fault
506 // here if the underlying file has been truncated.
507 // Do not crash the VM in such a case.
508 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
509 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
510 if (nm != NULL && nm->has_unsafe_access()) {
511 stub = StubRoutines::handler_for_unsafe_access();
512 }
513 }
514 else
515 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
516 // integer divide by zero
517 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
518 }
519 #ifndef AMD64
520 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
521 // floating-point divide by zero
522 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
523 }
524 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
525 // The encoding of D2I in i486.ad can cause an exception prior
526 // to the fist instruction if there was an invalid operation
527 // pending. We want to dismiss that exception. From the win_32
528 // side it also seems that if it really was the fist causing
529 // the exception that we do the d2i by hand with different
530 // rounding. Seems kind of weird. QQQ TODO
531 // Note that we take the exception at the NEXT floating point instruction.
532 if (pc[0] == 0xDB) {
533 assert(pc[0] == 0xDB, "not a FIST opcode");
534 assert(pc[1] == 0x14, "not a FIST opcode");
535 assert(pc[2] == 0x24, "not a FIST opcode");
536 return true;
537 } else {
538 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
539 assert(pc[-2] == 0x14, "not an flt invalid opcode");
540 assert(pc[-1] == 0x24, "not an flt invalid opcode");
541 }
542 }
543 else if (sig == SIGFPE ) {
544 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
545 }
546 #endif // !AMD64
547
548 // QQQ It doesn't seem that we need to do this on x86 because we should be able
549 // to return properly from the handler without this extra stuff on the back side.
550
551 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
552 // Determination of interpreter/vtable stub/compiled code null exception
553 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
554 }
555 }
556
557 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
558 // and the heap gets shrunk before the field access.
559 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
560 address addr = JNI_FastGetField::find_slowcase_pc(pc);
561 if (addr != (address)-1) {
562 stub = addr;
563 }
564 }
565
566 // Check to see if we caught the safepoint code in the
567 // process of write protecting the memory serialization page.
568 // It write enables the page immediately after protecting it
569 // so we can just return to retry the write.
570 if ((sig == SIGSEGV) &&
571 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
572 // Block current thread until the memory serialize page permission restored.
573 os::block_on_serialize_page_trap();
574 return true;
575 }
576 }
577
578 // Execution protection violation
579 //
580 // Preventative code for future versions of Solaris which may
581 // enable execution protection when running the 32-bit VM on AMD64.
582 //
583 // This should be kept as the last step in the triage. We don't
584 // have a dedicated trap number for a no-execute fault, so be
585 // conservative and allow other handlers the first shot.
586 //
587 // Note: We don't test that info->si_code == SEGV_ACCERR here.
588 // this si_code is so generic that it is almost meaningless; and
589 // the si_code for this condition may change in the future.
590 // Furthermore, a false-positive should be harmless.
591 if (UnguardOnExecutionViolation > 0 &&
592 (sig == SIGSEGV || sig == SIGBUS) &&
593 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
594 int page_size = os::vm_page_size();
595 address addr = (address) info->si_addr;
596 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
597 // Make sure the pc and the faulting address are sane.
598 //
599 // If an instruction spans a page boundary, and the page containing
600 // the beginning of the instruction is executable but the following
601 // page is not, the pc and the faulting address might be slightly
602 // different - we still want to unguard the 2nd page in this case.
603 //
604 // 15 bytes seems to be a (very) safe value for max instruction size.
605 bool pc_is_near_addr =
606 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
607 bool instr_spans_page_boundary =
608 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
609 (intptr_t) page_size) > 0);
610
611 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
612 static volatile address last_addr =
613 (address) os::non_memory_address_word();
614
615 // In conservative mode, don't unguard unless the address is in the VM
616 if (addr != last_addr &&
617 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
618
619 // Make memory rwx and retry
620 address page_start =
621 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
622 bool res = os::protect_memory((char*) page_start, page_size,
623 os::MEM_PROT_RWX);
624
625 if (PrintMiscellaneous && Verbose) {
626 char buf[256];
627 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
628 "at " INTPTR_FORMAT
629 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
630 page_start, (res ? "success" : "failed"), errno);
631 tty->print_raw_cr(buf);
632 }
633 stub = pc;
634
635 // Set last_addr so if we fault again at the same address, we don't end
636 // up in an endless loop.
637 //
638 // There are two potential complications here. Two threads trapping at
639 // the same address at the same time could cause one of the threads to
640 // think it already unguarded, and abort the VM. Likely very rare.
641 //
642 // The other race involves two threads alternately trapping at
643 // different addresses and failing to unguard the page, resulting in
644 // an endless loop. This condition is probably even more unlikely than
645 // the first.
646 //
647 // Although both cases could be avoided by using locks or thread local
648 // last_addr, these solutions are unnecessary complication: this
649 // handler is a best-effort safety net, not a complete solution. It is
650 // disabled by default and should only be used as a workaround in case
651 // we missed any no-execute-unsafe VM code.
652
653 last_addr = addr;
654 }
655 }
656 }
657
658 if (stub != NULL) {
659 // save all thread context in case we need to restore it
660
661 if (thread != NULL) thread->set_saved_exception_pc(pc);
662 // 12/02/99: On Sparc it appears that the full context is also saved
663 // but as yet, no one looks at or restores that saved context
664 // factor me: setPC
665 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub;
666 return true;
667 }
668
669 // signal-chaining
670 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
671 return true;
672 }
673
674 #ifndef AMD64
675 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
676 // Handle an undefined selector caused by an attempt to assign
677 // fs in libthread getipriptr(). With the current libthread design every 512
678 // thread creations the LDT for a private thread data structure is extended
679 // and thre is a hazard that and another thread attempting a thread creation
680 // will use a stale LDTR that doesn't reflect the structure's growth,
681 // causing a GP fault.
682 // Enforce the probable limit of passes through here to guard against an
683 // infinite loop if some other move to fs caused the GP fault. Note that
684 // this loop counter is ultimately a heuristic as it is possible for
685 // more than one thread to generate this fault at a time in an MP system.
686 // In the case of the loop count being exceeded or if the poll fails
687 // just fall through to a fatal error.
688 // If there is some other source of T_GPFLT traps and the text at EIP is
689 // unreadable this code will loop infinitely until the stack is exausted.
690 // The key to diagnosis in this case is to look for the bottom signal handler
691 // frame.
692
693 if(! IgnoreLibthreadGPFault) {
694 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
695 const unsigned char *p =
696 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
697
698 // Expected instruction?
699
700 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
701
702 Atomic::inc(&ldtr_refresh);
703
704 // Infinite loop?
705
706 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
707
708 // No, force scheduling to get a fresh view of the LDTR
709
710 if(poll(NULL, 0, 10) == 0) {
711
712 // Retry the move
713
714 return false;
715 }
716 }
717 }
718 }
719 }
720 #endif // !AMD64
721
722 if (!abort_if_unrecognized) {
723 // caller wants another chance, so give it to him
724 return false;
725 }
726
727 if (!os::Solaris::libjsig_is_loaded) {
728 struct sigaction oldAct;
729 sigaction(sig, (struct sigaction *)0, &oldAct);
730 if (oldAct.sa_sigaction != signalHandler) {
731 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
732 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
733 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
734 }
735 }
736
737 if (pc == NULL && uc != NULL) {
738 pc = (address) uc->uc_mcontext.gregs[REG_PC];
739 }
740
741 // unmask current signal
742 sigset_t newset;
743 sigemptyset(&newset);
744 sigaddset(&newset, sig);
745 sigprocmask(SIG_UNBLOCK, &newset, NULL);
746
747 VMError err(t, sig, pc, info, ucVoid);
748 err.report_and_die();
749
750 ShouldNotReachHere();
751 }
752
753 void os::print_context(outputStream *st, void *context) {
754 if (context == NULL) return;
755
756 ucontext_t *uc = (ucontext_t*)context;
757 st->print_cr("Registers:");
758
759 // this is horrendously verbose but the layout of the registers in the
760 // context does not match how we defined our abstract Register set, so
761 // we can't just iterate through the gregs area
762
763 #ifdef AMD64
764 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
765 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
766 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
767 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
768 st->cr();
769 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
770 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
771 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
772 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
773 st->cr();
774 st->print( "R8=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
775 st->print(", R9=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
776 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
777 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
778 st->cr();
779 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
780 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
781 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
782 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
783 st->cr();
784 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
785 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]);
786
787 st->cr();
788 st->cr();
789
790 st->print_cr("Register to memory mapping:");
791 st->cr();
792
793 // this is only for the "general purpose" registers
794
795 st->print_cr("RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
796 print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
797 st->cr();
798 st->print_cr("RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
799 print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
800 st->cr();
801 st->print_cr("RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
802 print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
803 st->cr();
804 st->print_cr("RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
805 print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
806 st->cr();
807 st->print_cr("RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
808 print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
809 st->cr();
810 st->print_cr("RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
811 print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
812 st->cr();
813 st->print_cr("RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
814 print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
815 st->cr();
816 st->print_cr("RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
817 print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
818 st->cr();
819 st->print_cr("R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
820 print_location(st, uc->uc_mcontext.gregs[REG_R8]);
821 st->cr();
822 st->print_cr("R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
823 print_location(st, uc->uc_mcontext.gregs[REG_R9]);
824 st->cr();
825 st->print_cr("R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
826 print_location(st, uc->uc_mcontext.gregs[REG_R10]);
827 st->cr();
828 st->print_cr("R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
829 print_location(st, uc->uc_mcontext.gregs[REG_R11]);
830 st->cr();
831 st->print_cr("R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
832 print_location(st, uc->uc_mcontext.gregs[REG_R12]);
833 st->cr();
834 st->print_cr("R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
835 print_location(st, uc->uc_mcontext.gregs[REG_R13]);
836 st->cr();
837 st->print_cr("R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
838 print_location(st, uc->uc_mcontext.gregs[REG_R14]);
839 st->cr();
840 st->print_cr("R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
841 print_location(st, uc->uc_mcontext.gregs[REG_R15]);
842
843 #else
844 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
845 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
846 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
847 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
848 st->cr();
849 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
850 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
851 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
852 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
853 st->cr();
854 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
855 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
856
857 st->cr();
858 st->cr();
859
860 st->print_cr("Register to memory mapping:");
861 st->cr();
862
863 // this is only for the "general purpose" registers
864
865 st->print_cr("EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
866 print_location(st, uc->uc_mcontext.gregs[EAX]);
867 st->cr();
868 st->print_cr("EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
869 print_location(st, uc->uc_mcontext.gregs[EBX]);
870 st->cr();
871 st->print_cr("ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
872 print_location(st, uc->uc_mcontext.gregs[ECX]);
873 st->cr();
874 st->print_cr("EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
875 print_location(st, uc->uc_mcontext.gregs[EDX]);
876 st->cr();
877 st->print_cr("ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
878 print_location(st, uc->uc_mcontext.gregs[UESP]);
879 st->cr();
880 st->print_cr("EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
881 print_location(st, uc->uc_mcontext.gregs[EBP]);
882 st->cr();
883 st->print_cr("ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
884 print_location(st, uc->uc_mcontext.gregs[ESI]);
885 st->cr();
886 st->print_cr("EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
887 print_location(st, uc->uc_mcontext.gregs[EDI]);
888
889 #endif // AMD64
890 st->cr();
891 st->cr();
892
893 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
894 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
895 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
896 st->cr();
897
898 // Note: it may be unsafe to inspect memory near pc. For example, pc may
899 // point to garbage if entry point in an nmethod is corrupted. Leave
900 // this at the end, and hope for the best.
901 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
902 address pc = epc.pc();
903 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
904 print_hex_dump(st, pc - 16, pc + 16, sizeof(char));
905 }
906
907
908 #ifdef AMD64
909 void os::Solaris::init_thread_fpu_state(void) {
910 // Nothing to do
911 }
912 #else
913 // From solaris_i486.s
914 extern "C" void fixcw();
915
916 void os::Solaris::init_thread_fpu_state(void) {
917 // Set fpu to 53 bit precision. This happens too early to use a stub.
918 fixcw();
919 }
920
921 // These routines are the initial value of atomic_xchg_entry(),
922 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
923 // until initialization is complete.
924 // TODO - replace with .il implementation when compiler supports it.
925
926 typedef jint xchg_func_t (jint, volatile jint*);
927 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
928 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
929 typedef jint add_func_t (jint, volatile jint*);
930
931 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
932 // try to use the stub:
933 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
934
935 if (func != NULL) {
936 os::atomic_xchg_func = func;
937 return (*func)(exchange_value, dest);
938 }
939 assert(Threads::number_of_threads() == 0, "for bootstrap only");
940
941 jint old_value = *dest;
942 *dest = exchange_value;
943 return old_value;
944 }
945
946 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
947 // try to use the stub:
948 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
949
950 if (func != NULL) {
951 os::atomic_cmpxchg_func = func;
952 return (*func)(exchange_value, dest, compare_value);
953 }
954 assert(Threads::number_of_threads() == 0, "for bootstrap only");
955
956 jint old_value = *dest;
957 if (old_value == compare_value)
958 *dest = exchange_value;
959 return old_value;
960 }
961
962 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
963 // try to use the stub:
964 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
965
966 if (func != NULL) {
967 os::atomic_cmpxchg_long_func = func;
968 return (*func)(exchange_value, dest, compare_value);
969 }
970 assert(Threads::number_of_threads() == 0, "for bootstrap only");
971
972 jlong old_value = *dest;
973 if (old_value == compare_value)
974 *dest = exchange_value;
975 return old_value;
976 }
977
978 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
979 // try to use the stub:
980 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
981
982 if (func != NULL) {
983 os::atomic_add_func = func;
984 return (*func)(add_value, dest);
985 }
986 assert(Threads::number_of_threads() == 0, "for bootstrap only");
987
988 return (*dest) += add_value;
989 }
990
991 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
992 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
993 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
994 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
995
996 extern "C" void _solaris_raw_setup_fpu(address ptr);
997 void os::setup_fpu() {
998 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
999 _solaris_raw_setup_fpu(fpu_cntrl);
1000 }
1001 #endif // AMD64