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 // no precompiled headers
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 // put OS-includes here
64 # include <sys/types.h>
65 # include <sys/mman.h>
66 # include <pthread.h>
67 # include <signal.h>
68 # include <setjmp.h>
69 # include <errno.h>
70 # include <dlfcn.h>
71 # include <stdio.h>
72 # include <unistd.h>
73 # include <sys/resource.h>
74 # include <thread.h>
75 # include <sys/stat.h>
76 # include <sys/time.h>
77 # include <sys/filio.h>
78 # include <sys/utsname.h>
79 # include <sys/systeminfo.h>
80 # include <sys/socket.h>
81 # include <sys/trap.h>
82 # include <sys/lwp.h>
83 # include <pwd.h>
84 # include <poll.h>
85 # include <sys/lwp.h>
86 # include <procfs.h> // see comment in <sys/procfs.h>
87
88 #ifndef AMD64
89 // QQQ seems useless at this point
90 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
91 #endif // AMD64
92 # include <sys/procfs.h> // see comment in <sys/procfs.h>
93
94
95 #define MAX_PATH (2 * K)
96
97 // Minimum stack size for the VM. It's easier to document a constant value
98 // but it's different for x86 and sparc because the page sizes are different.
99 #ifdef AMD64
100 size_t os::Solaris::min_stack_allowed = 224*K;
101 #define REG_SP REG_RSP
102 #define REG_PC REG_RIP
103 #define REG_FP REG_RBP
104 #else
105 size_t os::Solaris::min_stack_allowed = 64*K;
106 #define REG_SP UESP
107 #define REG_PC EIP
108 #define REG_FP EBP
109 // 4900493 counter to prevent runaway LDTR refresh attempt
110
111 static volatile int ldtr_refresh = 0;
112 // the libthread instruction that faults because of the stale LDTR
113
114 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
115 };
116 #endif // AMD64
117
118 char* os::non_memory_address_word() {
119 // Must never look like an address returned by reserve_memory,
120 // even in its subfields (as defined by the CPU immediate fields,
121 // if the CPU splits constants across multiple instructions).
122 return (char*) -1;
123 }
124
125 //
126 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
127 // There are issues with libthread giving out uc_links for different threads
128 // on the same uc_link chain and bad or circular links.
129 //
130 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
131 if (valid >= suspect ||
132 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
133 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
134 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
135 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
136 return false;
137 }
138
139 if (thread->is_Java_thread()) {
140 if (!valid_stack_address(thread, (address)suspect)) {
141 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
142 return false;
143 }
144 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
145 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
146 return false;
147 }
148 }
149 return true;
150 }
151
152 // We will only follow one level of uc_link since there are libthread
153 // issues with ucontext linking and it is better to be safe and just
154 // let caller retry later.
155 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
156 ucontext_t *uc) {
157
158 ucontext_t *retuc = NULL;
159
160 if (uc != NULL) {
161 if (uc->uc_link == NULL) {
162 // cannot validate without uc_link so accept current ucontext
163 retuc = uc;
164 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
165 // first ucontext is valid so try the next one
166 uc = uc->uc_link;
167 if (uc->uc_link == NULL) {
168 // cannot validate without uc_link so accept current ucontext
169 retuc = uc;
170 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
171 // the ucontext one level down is also valid so return it
172 retuc = uc;
173 }
174 }
175 }
176 return retuc;
177 }
178
179 // Assumes ucontext is valid
180 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
181 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
182 }
183
184 // Assumes ucontext is valid
185 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
186 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
187 }
188
189 // Assumes ucontext is valid
190 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
191 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
192 }
193
194 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
195 // is currently interrupted by SIGPROF.
196 //
197 // The difference between this and os::fetch_frame_from_context() is that
198 // here we try to skip nested signal frames.
199 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
200 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
201
202 assert(thread != NULL, "just checking");
203 assert(ret_sp != NULL, "just checking");
204 assert(ret_fp != NULL, "just checking");
205
206 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
207 return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
208 }
209
210 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
211 intptr_t** ret_sp, intptr_t** ret_fp) {
212
213 ExtendedPC epc;
214 ucontext_t *uc = (ucontext_t*)ucVoid;
215
216 if (uc != NULL) {
217 epc = os::Solaris::ucontext_get_ExtendedPC(uc);
218 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
219 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc);
220 } else {
221 // construct empty ExtendedPC for return value checking
222 epc = ExtendedPC(NULL);
223 if (ret_sp) *ret_sp = (intptr_t *)NULL;
224 if (ret_fp) *ret_fp = (intptr_t *)NULL;
225 }
226
227 return epc;
228 }
229
230 frame os::fetch_frame_from_context(void* ucVoid) {
231 intptr_t* sp;
232 intptr_t* fp;
233 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
234 return frame(sp, fp, epc.pc());
235 }
236
237 frame os::get_sender_for_C_frame(frame* fr) {
238 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
239 }
240
241 extern "C" intptr_t *_get_current_fp(); // in .il file
242
243 frame os::current_frame() {
244 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
245 frame myframe((intptr_t*)os::current_stack_pointer(),
246 (intptr_t*)fp,
247 CAST_FROM_FN_PTR(address, os::current_frame));
248 if (os::is_first_C_frame(&myframe)) {
249 // stack is not walkable
250 frame ret; // This will be a null useless frame
251 return ret;
252 } else {
253 return os::get_sender_for_C_frame(&myframe);
254 }
255 }
256
257 // This is a simple callback that just fetches a PC for an interrupted thread.
258 // The thread need not be suspended and the fetched PC is just a hint.
259 // This one is currently used for profiling the VMThread ONLY!
260
261 // Must be synchronous
262 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {
263 Thread* thread = args->thread();
264 ucontext_t* uc = args->ucontext();
265 intptr_t* sp;
266
267 assert(ProfileVM && thread->is_VM_thread(), "just checking");
268
269 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);
270 _addr = new_addr;
271 }
272
273 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
274 char lwpstatusfile[PROCFILE_LENGTH];
275 int lwpfd, err;
276
277 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
278 return (err);
279 if (*flags == TRS_LWPID) {
280 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
281 *lwp);
282 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
283 perror("thr_mutator_status: open lwpstatus");
284 return (EINVAL);
285 }
286 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
287 sizeof (lwpstatus_t)) {
288 perror("thr_mutator_status: read lwpstatus");
289 (void) close(lwpfd);
290 return (EINVAL);
291 }
292 (void) close(lwpfd);
293 }
294 return (0);
295 }
296
297 #ifndef AMD64
298
299 // Detecting SSE support by OS
300 // From solaris_i486.s
301 extern "C" bool sse_check();
302 extern "C" bool sse_unavailable();
303
304 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
305 static int sse_status = SSE_UNKNOWN;
306
307
308 static void check_for_sse_support() {
309 if (!VM_Version::supports_sse()) {
310 sse_status = SSE_NOT_SUPPORTED;
311 return;
312 }
313 // looking for _sse_hw in libc.so, if it does not exist or
314 // the value (int) is 0, OS has no support for SSE
315 int *sse_hwp;
316 void *h;
317
318 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
319 //open failed, presume no support for SSE
320 sse_status = SSE_NOT_SUPPORTED;
321 return;
322 }
323 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
324 sse_status = SSE_NOT_SUPPORTED;
325 } else if (*sse_hwp == 0) {
326 sse_status = SSE_NOT_SUPPORTED;
327 }
328 dlclose(h);
329
330 if (sse_status == SSE_UNKNOWN) {
331 bool (*try_sse)() = (bool (*)())sse_check;
332 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
333 }
334
335 }
336
337 #endif // AMD64
338
339 bool os::supports_sse() {
340 #ifdef AMD64
341 return true;
342 #else
343 if (sse_status == SSE_UNKNOWN)
344 check_for_sse_support();
345 return sse_status == SSE_SUPPORTED;
346 #endif // AMD64
347 }
348
349 bool os::is_allocatable(size_t bytes) {
350 #ifdef AMD64
351 return true;
352 #else
353
354 if (bytes < 2 * G) {
355 return true;
356 }
357
358 char* addr = reserve_memory(bytes, NULL);
359
360 if (addr != NULL) {
361 release_memory(addr, bytes);
362 }
363
364 return addr != NULL;
365 #endif // AMD64
366
367 }
368
369 extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
370
371 extern "C" void Fetch32PFI () ;
372 extern "C" void Fetch32Resume () ;
373 #ifdef AMD64
374 extern "C" void FetchNPFI () ;
375 extern "C" void FetchNResume () ;
376 #endif // AMD64
377
378 int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {
379 ucontext_t* uc = (ucontext_t*) ucVoid;
380
381 #ifndef AMD64
382 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
383 // the SSE instruction faulted. supports_sse() need return false.
384 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
385 return true;
386 }
387 #endif // !AMD64
388
389 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
390
391 SignalHandlerMark shm(t);
392
393 if(sig == SIGPIPE || sig == SIGXFSZ) {
394 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
395 return true;
396 } else {
397 if (PrintMiscellaneous && (WizardMode || Verbose)) {
398 char buf[64];
399 warning("Ignoring %s - see 4229104 or 6499219",
400 os::exception_name(sig, buf, sizeof(buf)));
401
402 }
403 return true;
404 }
405 }
406
407 JavaThread* thread = NULL;
408 VMThread* vmthread = NULL;
409
410 if (os::Solaris::signal_handlers_are_installed) {
411 if (t != NULL ){
412 if(t->is_Java_thread()) {
413 thread = (JavaThread*)t;
414 }
415 else if(t->is_VM_thread()){
416 vmthread = (VMThread *)t;
417 }
418 }
419 }
420
421 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
422
423 if (sig == os::Solaris::SIGasync()) {
424 if(thread){
425 OSThread::InterruptArguments args(thread, uc);
426 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
427 return true;
428 }
429 else if(vmthread){
430 OSThread::InterruptArguments args(vmthread, uc);
431 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
432 return true;
433 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
434 return true;
435 } else {
436 // If os::Solaris::SIGasync not chained, and this is a non-vm and
437 // non-java thread
438 return true;
439 }
440 }
441
442 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
443 // can't decode this kind of signal
444 info = NULL;
445 } else {
446 assert(sig == info->si_signo, "bad siginfo");
447 }
448
449 // decide if this trap can be handled by a stub
450 address stub = NULL;
451
452 address pc = NULL;
453
454 //%note os_trap_1
455 if (info != NULL && uc != NULL && thread != NULL) {
456 // factor me: getPCfromContext
457 pc = (address) uc->uc_mcontext.gregs[REG_PC];
458
459 // SafeFetch32() support
460 if (pc == (address) Fetch32PFI) {
461 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
462 return true ;
463 }
464 #ifdef AMD64
465 if (pc == (address) FetchNPFI) {
466 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ;
467 return true ;
468 }
469 #endif // AMD64
470
471 // Handle ALL stack overflow variations here
472 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
473 address addr = (address) info->si_addr;
474 if (thread->in_stack_yellow_zone(addr)) {
475 thread->disable_stack_yellow_zone();
476 if (thread->thread_state() == _thread_in_Java) {
477 // Throw a stack overflow exception. Guard pages will be reenabled
478 // while unwinding the stack.
479 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
480 } else {
481 // Thread was in the vm or native code. Return and try to finish.
482 return true;
483 }
484 } else if (thread->in_stack_red_zone(addr)) {
485 // Fatal red zone violation. Disable the guard pages and fall through
486 // to handle_unexpected_exception way down below.
487 thread->disable_stack_red_zone();
488 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
489 }
490 }
491
492 if (thread->thread_state() == _thread_in_vm) {
493 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
494 stub = StubRoutines::handler_for_unsafe_access();
495 }
496 }
497
498 if (thread->thread_state() == _thread_in_Java) {
499 // Support Safepoint Polling
500 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
501 stub = SharedRuntime::get_poll_stub(pc);
502 }
503 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
504 // BugId 4454115: A read from a MappedByteBuffer can fault
505 // here if the underlying file has been truncated.
506 // Do not crash the VM in such a case.
507 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
508 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
509 if (nm != NULL && nm->has_unsafe_access()) {
510 stub = StubRoutines::handler_for_unsafe_access();
511 }
512 }
513 else
514 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
515 // integer divide by zero
516 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
517 }
518 #ifndef AMD64
519 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
520 // floating-point divide by zero
521 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
522 }
523 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
524 // The encoding of D2I in i486.ad can cause an exception prior
525 // to the fist instruction if there was an invalid operation
526 // pending. We want to dismiss that exception. From the win_32
527 // side it also seems that if it really was the fist causing
528 // the exception that we do the d2i by hand with different
529 // rounding. Seems kind of weird. QQQ TODO
530 // Note that we take the exception at the NEXT floating point instruction.
531 if (pc[0] == 0xDB) {
532 assert(pc[0] == 0xDB, "not a FIST opcode");
533 assert(pc[1] == 0x14, "not a FIST opcode");
534 assert(pc[2] == 0x24, "not a FIST opcode");
535 return true;
536 } else {
537 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
538 assert(pc[-2] == 0x14, "not an flt invalid opcode");
539 assert(pc[-1] == 0x24, "not an flt invalid opcode");
540 }
541 }
542 else if (sig == SIGFPE ) {
543 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
544 }
545 #endif // !AMD64
546
547 // QQQ It doesn't seem that we need to do this on x86 because we should be able
548 // to return properly from the handler without this extra stuff on the back side.
549
550 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
551 // Determination of interpreter/vtable stub/compiled code null exception
552 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
553 }
554 }
555
556 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
557 // and the heap gets shrunk before the field access.
558 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
559 address addr = JNI_FastGetField::find_slowcase_pc(pc);
560 if (addr != (address)-1) {
561 stub = addr;
562 }
563 }
564
565 // Check to see if we caught the safepoint code in the
566 // process of write protecting the memory serialization page.
567 // It write enables the page immediately after protecting it
568 // so we can just return to retry the write.
569 if ((sig == SIGSEGV) &&
570 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
571 // Block current thread until the memory serialize page permission restored.
572 os::block_on_serialize_page_trap();
573 return true;
574 }
575 }
576
577 // Execution protection violation
578 //
579 // Preventative code for future versions of Solaris which may
580 // enable execution protection when running the 32-bit VM on AMD64.
581 //
582 // This should be kept as the last step in the triage. We don't
583 // have a dedicated trap number for a no-execute fault, so be
584 // conservative and allow other handlers the first shot.
585 //
586 // Note: We don't test that info->si_code == SEGV_ACCERR here.
587 // this si_code is so generic that it is almost meaningless; and
588 // the si_code for this condition may change in the future.
589 // Furthermore, a false-positive should be harmless.
590 if (UnguardOnExecutionViolation > 0 &&
591 (sig == SIGSEGV || sig == SIGBUS) &&
592 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
593 int page_size = os::vm_page_size();
594 address addr = (address) info->si_addr;
595 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
596 // Make sure the pc and the faulting address are sane.
597 //
598 // If an instruction spans a page boundary, and the page containing
599 // the beginning of the instruction is executable but the following
600 // page is not, the pc and the faulting address might be slightly
601 // different - we still want to unguard the 2nd page in this case.
602 //
603 // 15 bytes seems to be a (very) safe value for max instruction size.
604 bool pc_is_near_addr =
605 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
606 bool instr_spans_page_boundary =
607 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
608 (intptr_t) page_size) > 0);
609
610 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
611 static volatile address last_addr =
612 (address) os::non_memory_address_word();
613
614 // In conservative mode, don't unguard unless the address is in the VM
615 if (addr != last_addr &&
616 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
617
618 // Make memory rwx and retry
619 address page_start =
620 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
621 bool res = os::protect_memory((char*) page_start, page_size,
622 os::MEM_PROT_RWX);
623
624 if (PrintMiscellaneous && Verbose) {
625 char buf[256];
626 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
627 "at " INTPTR_FORMAT
628 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
629 page_start, (res ? "success" : "failed"), errno);
630 tty->print_raw_cr(buf);
631 }
632 stub = pc;
633
634 // Set last_addr so if we fault again at the same address, we don't end
635 // up in an endless loop.
636 //
637 // There are two potential complications here. Two threads trapping at
638 // the same address at the same time could cause one of the threads to
639 // think it already unguarded, and abort the VM. Likely very rare.
640 //
641 // The other race involves two threads alternately trapping at
642 // different addresses and failing to unguard the page, resulting in
643 // an endless loop. This condition is probably even more unlikely than
644 // the first.
645 //
646 // Although both cases could be avoided by using locks or thread local
647 // last_addr, these solutions are unnecessary complication: this
648 // handler is a best-effort safety net, not a complete solution. It is
649 // disabled by default and should only be used as a workaround in case
650 // we missed any no-execute-unsafe VM code.
651
652 last_addr = addr;
653 }
654 }
655 }
656
657 if (stub != NULL) {
658 // save all thread context in case we need to restore it
659
660 if (thread != NULL) thread->set_saved_exception_pc(pc);
661 // 12/02/99: On Sparc it appears that the full context is also saved
662 // but as yet, no one looks at or restores that saved context
663 // factor me: setPC
664 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub;
665 return true;
666 }
667
668 // signal-chaining
669 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
670 return true;
671 }
672
673 #ifndef AMD64
674 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
675 // Handle an undefined selector caused by an attempt to assign
676 // fs in libthread getipriptr(). With the current libthread design every 512
677 // thread creations the LDT for a private thread data structure is extended
678 // and thre is a hazard that and another thread attempting a thread creation
679 // will use a stale LDTR that doesn't reflect the structure's growth,
680 // causing a GP fault.
681 // Enforce the probable limit of passes through here to guard against an
682 // infinite loop if some other move to fs caused the GP fault. Note that
683 // this loop counter is ultimately a heuristic as it is possible for
684 // more than one thread to generate this fault at a time in an MP system.
685 // In the case of the loop count being exceeded or if the poll fails
686 // just fall through to a fatal error.
687 // If there is some other source of T_GPFLT traps and the text at EIP is
688 // unreadable this code will loop infinitely until the stack is exausted.
689 // The key to diagnosis in this case is to look for the bottom signal handler
690 // frame.
691
692 if(! IgnoreLibthreadGPFault) {
693 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
694 const unsigned char *p =
695 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
696
697 // Expected instruction?
698
699 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
700
701 Atomic::inc(&ldtr_refresh);
702
703 // Infinite loop?
704
705 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
706
707 // No, force scheduling to get a fresh view of the LDTR
708
709 if(poll(NULL, 0, 10) == 0) {
710
711 // Retry the move
712
713 return false;
714 }
715 }
716 }
717 }
718 }
719 #endif // !AMD64
720
721 if (!abort_if_unrecognized) {
722 // caller wants another chance, so give it to him
723 return false;
724 }
725
726 if (!os::Solaris::libjsig_is_loaded) {
727 struct sigaction oldAct;
728 sigaction(sig, (struct sigaction *)0, &oldAct);
729 if (oldAct.sa_sigaction != signalHandler) {
730 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
731 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
732 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
733 }
734 }
735
736 if (pc == NULL && uc != NULL) {
737 pc = (address) uc->uc_mcontext.gregs[REG_PC];
738 }
739
740 // unmask current signal
741 sigset_t newset;
742 sigemptyset(&newset);
743 sigaddset(&newset, sig);
744 sigprocmask(SIG_UNBLOCK, &newset, NULL);
745
746 VMError err(t, sig, pc, info, ucVoid);
747 err.report_and_die();
748
749 ShouldNotReachHere();
750 }
751
752 void os::print_context(outputStream *st, void *context) {
753 if (context == NULL) return;
754
755 ucontext_t *uc = (ucontext_t*)context;
756 st->print_cr("Registers:");
757
758 // this is horrendously verbose but the layout of the registers in the
759 // context does not match how we defined our abstract Register set, so
760 // we can't just iterate through the gregs area
761
762 #ifdef AMD64
763 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
764 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
765 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
766 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
767 st->cr();
768 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
769 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
770 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
771 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
772 st->cr();
773 st->print( "R8=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
774 st->print(", R9=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
775 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
776 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
777 st->cr();
778 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
779 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
780 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
781 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
782 st->cr();
783 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
784 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]);
785
786 st->cr();
787 st->cr();
788
789 st->print_cr("Register to memory mapping:");
790 st->cr();
791
792 // this is only for the "general purpose" registers
793
794 st->print_cr("RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
795 print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
796 st->cr();
797 st->print_cr("RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
798 print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
799 st->cr();
800 st->print_cr("RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
801 print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
802 st->cr();
803 st->print_cr("RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
804 print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
805 st->cr();
806 st->print_cr("RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
807 print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
808 st->cr();
809 st->print_cr("RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
810 print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
811 st->cr();
812 st->print_cr("RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
813 print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
814 st->cr();
815 st->print_cr("RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
816 print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
817 st->cr();
818 st->print_cr("R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
819 print_location(st, uc->uc_mcontext.gregs[REG_R8]);
820 st->cr();
821 st->print_cr("R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
822 print_location(st, uc->uc_mcontext.gregs[REG_R9]);
823 st->cr();
824 st->print_cr("R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
825 print_location(st, uc->uc_mcontext.gregs[REG_R10]);
826 st->cr();
827 st->print_cr("R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
828 print_location(st, uc->uc_mcontext.gregs[REG_R11]);
829 st->cr();
830 st->print_cr("R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
831 print_location(st, uc->uc_mcontext.gregs[REG_R12]);
832 st->cr();
833 st->print_cr("R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
834 print_location(st, uc->uc_mcontext.gregs[REG_R13]);
835 st->cr();
836 st->print_cr("R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
837 print_location(st, uc->uc_mcontext.gregs[REG_R14]);
838 st->cr();
839 st->print_cr("R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
840 print_location(st, uc->uc_mcontext.gregs[REG_R15]);
841
842 #else
843 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
844 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
845 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
846 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
847 st->cr();
848 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
849 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
850 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
851 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
852 st->cr();
853 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
854 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
855
856 st->cr();
857 st->cr();
858
859 st->print_cr("Register to memory mapping:");
860 st->cr();
861
862 // this is only for the "general purpose" registers
863
864 st->print_cr("EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
865 print_location(st, uc->uc_mcontext.gregs[EAX]);
866 st->cr();
867 st->print_cr("EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
868 print_location(st, uc->uc_mcontext.gregs[EBX]);
869 st->cr();
870 st->print_cr("ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
871 print_location(st, uc->uc_mcontext.gregs[ECX]);
872 st->cr();
873 st->print_cr("EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
874 print_location(st, uc->uc_mcontext.gregs[EDX]);
875 st->cr();
876 st->print_cr("ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
877 print_location(st, uc->uc_mcontext.gregs[UESP]);
878 st->cr();
879 st->print_cr("EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
880 print_location(st, uc->uc_mcontext.gregs[EBP]);
881 st->cr();
882 st->print_cr("ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
883 print_location(st, uc->uc_mcontext.gregs[ESI]);
884 st->cr();
885 st->print_cr("EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
886 print_location(st, uc->uc_mcontext.gregs[EDI]);
887
888 #endif // AMD64
889 st->cr();
890 st->cr();
891
892 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
893 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
894 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
895 st->cr();
896
897 // Note: it may be unsafe to inspect memory near pc. For example, pc may
898 // point to garbage if entry point in an nmethod is corrupted. Leave
899 // this at the end, and hope for the best.
900 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
901 address pc = epc.pc();
902 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
903 print_hex_dump(st, pc - 16, pc + 16, sizeof(char));
904 }
905
906
907 #ifdef AMD64
908 void os::Solaris::init_thread_fpu_state(void) {
909 // Nothing to do
910 }
911 #else
912 // From solaris_i486.s
913 extern "C" void fixcw();
914
915 void os::Solaris::init_thread_fpu_state(void) {
916 // Set fpu to 53 bit precision. This happens too early to use a stub.
917 fixcw();
918 }
919
920 // These routines are the initial value of atomic_xchg_entry(),
921 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
922 // until initialization is complete.
923 // TODO - replace with .il implementation when compiler supports it.
924
925 typedef jint xchg_func_t (jint, volatile jint*);
926 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
927 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
928 typedef jint add_func_t (jint, volatile jint*);
929
930 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
931 // try to use the stub:
932 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
933
934 if (func != NULL) {
935 os::atomic_xchg_func = func;
936 return (*func)(exchange_value, dest);
937 }
938 assert(Threads::number_of_threads() == 0, "for bootstrap only");
939
940 jint old_value = *dest;
941 *dest = exchange_value;
942 return old_value;
943 }
944
945 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
946 // try to use the stub:
947 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
948
949 if (func != NULL) {
950 os::atomic_cmpxchg_func = func;
951 return (*func)(exchange_value, dest, compare_value);
952 }
953 assert(Threads::number_of_threads() == 0, "for bootstrap only");
954
955 jint old_value = *dest;
956 if (old_value == compare_value)
957 *dest = exchange_value;
958 return old_value;
959 }
960
961 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
962 // try to use the stub:
963 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
964
965 if (func != NULL) {
966 os::atomic_cmpxchg_long_func = func;
967 return (*func)(exchange_value, dest, compare_value);
968 }
969 assert(Threads::number_of_threads() == 0, "for bootstrap only");
970
971 jlong old_value = *dest;
972 if (old_value == compare_value)
973 *dest = exchange_value;
974 return old_value;
975 }
976
977 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
978 // try to use the stub:
979 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
980
981 if (func != NULL) {
982 os::atomic_add_func = func;
983 return (*func)(add_value, dest);
984 }
985 assert(Threads::number_of_threads() == 0, "for bootstrap only");
986
987 return (*dest) += add_value;
988 }
989
990 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
991 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
992 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
993 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
994
995 extern "C" void _solaris_raw_setup_fpu(address ptr);
996 void os::setup_fpu() {
997 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
998 _solaris_raw_setup_fpu(fpu_cntrl);
999 }
1000 #endif // AMD64