1 /*
2 * Copyright (c) 1999, 2011, 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/interfaceSupport.hpp"
45 #include "runtime/java.hpp"
46 #include "runtime/javaCalls.hpp"
47 #include "runtime/mutexLocker.hpp"
48 #include "runtime/osThread.hpp"
49 #include "runtime/sharedRuntime.hpp"
50 #include "runtime/stubRoutines.hpp"
51 #include "runtime/timer.hpp"
52 #include "thread_solaris.inline.hpp"
53 #include "utilities/events.hpp"
54 #include "utilities/vmError.hpp"
55 #ifdef COMPILER1
56 #include "c1/c1_Runtime1.hpp"
57 #endif
58 #ifdef COMPILER2
59 #include "opto/runtime.hpp"
60 #endif
61
62 // put OS-includes here
63 # include <sys/types.h>
64 # include <sys/mman.h>
65 # include <pthread.h>
66 # include <signal.h>
67 # include <setjmp.h>
68 # include <errno.h>
69 # include <dlfcn.h>
70 # include <stdio.h>
71 # include <unistd.h>
72 # include <sys/resource.h>
73 # include <thread.h>
74 # include <sys/stat.h>
75 # include <sys/time.h>
76 # include <sys/filio.h>
77 # include <sys/utsname.h>
78 # include <sys/systeminfo.h>
79 # include <sys/socket.h>
80 # include <sys/trap.h>
81 # include <sys/lwp.h>
82 # include <pwd.h>
83 # include <poll.h>
84 # include <sys/lwp.h>
85 # include <procfs.h> // see comment in <sys/procfs.h>
86
87 #ifndef AMD64
88 // QQQ seems useless at this point
89 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
90 #endif // AMD64
91 # include <sys/procfs.h> // see comment in <sys/procfs.h>
92
93
94 #define MAX_PATH (2 * K)
95
96 // Minimum stack size for the VM. It's easier to document a constant value
97 // but it's different for x86 and sparc because the page sizes are different.
98 #ifdef AMD64
99 size_t os::Solaris::min_stack_allowed = 224*K;
100 #define REG_SP REG_RSP
101 #define REG_PC REG_RIP
102 #define REG_FP REG_RBP
103 #else
104 size_t os::Solaris::min_stack_allowed = 64*K;
105 #define REG_SP UESP
106 #define REG_PC EIP
107 #define REG_FP EBP
108 // 4900493 counter to prevent runaway LDTR refresh attempt
109
110 static volatile int ldtr_refresh = 0;
111 // the libthread instruction that faults because of the stale LDTR
112
113 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
114 };
115 #endif // AMD64
116
117 char* os::non_memory_address_word() {
118 // Must never look like an address returned by reserve_memory,
119 // even in its subfields (as defined by the CPU immediate fields,
120 // if the CPU splits constants across multiple instructions).
121 return (char*) -1;
122 }
123
124 //
125 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
126 // There are issues with libthread giving out uc_links for different threads
127 // on the same uc_link chain and bad or circular links.
128 //
129 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
130 if (valid >= suspect ||
131 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
132 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
133 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
134 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
135 return false;
136 }
137
138 if (thread->is_Java_thread()) {
139 if (!valid_stack_address(thread, (address)suspect)) {
140 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
141 return false;
142 }
143 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
144 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
145 return false;
146 }
147 }
148 return true;
149 }
150
151 // We will only follow one level of uc_link since there are libthread
152 // issues with ucontext linking and it is better to be safe and just
153 // let caller retry later.
154 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
155 ucontext_t *uc) {
156
157 ucontext_t *retuc = NULL;
158
159 if (uc != NULL) {
160 if (uc->uc_link == NULL) {
161 // cannot validate without uc_link so accept current ucontext
162 retuc = uc;
163 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
164 // first ucontext is valid so try the next one
165 uc = uc->uc_link;
166 if (uc->uc_link == NULL) {
167 // cannot validate without uc_link so accept current ucontext
168 retuc = uc;
169 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
170 // the ucontext one level down is also valid so return it
171 retuc = uc;
172 }
173 }
174 }
175 return retuc;
176 }
177
178 // Assumes ucontext is valid
179 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
180 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
181 }
182
183 // Assumes ucontext is valid
184 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
185 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
186 }
187
188 // Assumes ucontext is valid
189 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
190 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
191 }
192
193 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
194 // is currently interrupted by SIGPROF.
195 //
196 // The difference between this and os::fetch_frame_from_context() is that
197 // here we try to skip nested signal frames.
198 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
199 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
200
201 assert(thread != NULL, "just checking");
202 assert(ret_sp != NULL, "just checking");
203 assert(ret_fp != NULL, "just checking");
204
205 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
206 return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
207 }
208
209 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
210 intptr_t** ret_sp, intptr_t** ret_fp) {
211
212 ExtendedPC epc;
213 ucontext_t *uc = (ucontext_t*)ucVoid;
214
215 if (uc != NULL) {
216 epc = os::Solaris::ucontext_get_ExtendedPC(uc);
217 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
218 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc);
219 } else {
220 // construct empty ExtendedPC for return value checking
221 epc = ExtendedPC(NULL);
222 if (ret_sp) *ret_sp = (intptr_t *)NULL;
223 if (ret_fp) *ret_fp = (intptr_t *)NULL;
224 }
225
226 return epc;
227 }
228
229 frame os::fetch_frame_from_context(void* ucVoid) {
230 intptr_t* sp;
231 intptr_t* fp;
232 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
233 return frame(sp, fp, epc.pc());
234 }
235
236 frame os::get_sender_for_C_frame(frame* fr) {
237 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
238 }
239
240 extern "C" intptr_t *_get_current_fp(); // in .il file
241
242 frame os::current_frame() {
243 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
244 frame myframe((intptr_t*)os::current_stack_pointer(),
245 (intptr_t*)fp,
246 CAST_FROM_FN_PTR(address, os::current_frame));
247 if (os::is_first_C_frame(&myframe)) {
248 // stack is not walkable
249 frame ret; // This will be a null useless frame
250 return ret;
251 } else {
252 return os::get_sender_for_C_frame(&myframe);
253 }
254 }
255
256 // This is a simple callback that just fetches a PC for an interrupted thread.
257 // The thread need not be suspended and the fetched PC is just a hint.
258 // This one is currently used for profiling the VMThread ONLY!
259
260 // Must be synchronous
261 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {
262 Thread* thread = args->thread();
263 ucontext_t* uc = args->ucontext();
264 intptr_t* sp;
265
266 assert(ProfileVM && thread->is_VM_thread(), "just checking");
267
268 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);
269 _addr = new_addr;
270 }
271
272 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
273 char lwpstatusfile[PROCFILE_LENGTH];
274 int lwpfd, err;
275
276 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
277 return (err);
278 if (*flags == TRS_LWPID) {
279 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
280 *lwp);
281 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
282 perror("thr_mutator_status: open lwpstatus");
283 return (EINVAL);
284 }
285 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
286 sizeof (lwpstatus_t)) {
287 perror("thr_mutator_status: read lwpstatus");
288 (void) close(lwpfd);
289 return (EINVAL);
290 }
291 (void) close(lwpfd);
292 }
293 return (0);
294 }
295
296 #ifndef AMD64
297
298 // Detecting SSE support by OS
299 // From solaris_i486.s
300 extern "C" bool sse_check();
301 extern "C" bool sse_unavailable();
302
303 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
304 static int sse_status = SSE_UNKNOWN;
305
306
307 static void check_for_sse_support() {
308 if (!VM_Version::supports_sse()) {
309 sse_status = SSE_NOT_SUPPORTED;
310 return;
311 }
312 // looking for _sse_hw in libc.so, if it does not exist or
313 // the value (int) is 0, OS has no support for SSE
314 int *sse_hwp;
315 void *h;
316
317 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
318 //open failed, presume no support for SSE
319 sse_status = SSE_NOT_SUPPORTED;
320 return;
321 }
322 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
323 sse_status = SSE_NOT_SUPPORTED;
324 } else if (*sse_hwp == 0) {
325 sse_status = SSE_NOT_SUPPORTED;
326 }
327 dlclose(h);
328
329 if (sse_status == SSE_UNKNOWN) {
330 bool (*try_sse)() = (bool (*)())sse_check;
331 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
332 }
333
334 }
335
336 #endif // AMD64
337
338 bool os::supports_sse() {
339 #ifdef AMD64
340 return true;
341 #else
342 if (sse_status == SSE_UNKNOWN)
343 check_for_sse_support();
344 return sse_status == SSE_SUPPORTED;
345 #endif // AMD64
346 }
347
348 bool os::is_allocatable(size_t bytes) {
349 #ifdef AMD64
350 return true;
351 #else
352
353 if (bytes < 2 * G) {
354 return true;
355 }
356
357 char* addr = reserve_memory(bytes, NULL);
358
359 if (addr != NULL) {
360 release_memory(addr, bytes);
361 }
362
363 return addr != NULL;
364 #endif // AMD64
365
366 }
367
368 extern "C" void Fetch32PFI () ;
369 extern "C" void Fetch32Resume () ;
370 #ifdef AMD64
371 extern "C" void FetchNPFI () ;
372 extern "C" void FetchNResume () ;
373 #endif // AMD64
374
375 extern "C" JNIEXPORT int
376 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid,
377 int abort_if_unrecognized) {
378 ucontext_t* uc = (ucontext_t*) ucVoid;
379
380 #ifndef AMD64
381 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
382 // the SSE instruction faulted. supports_sse() need return false.
383 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
384 return true;
385 }
386 #endif // !AMD64
387
388 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
389
390 SignalHandlerMark shm(t);
391
392 if(sig == SIGPIPE || sig == SIGXFSZ) {
393 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
394 return true;
395 } else {
396 if (PrintMiscellaneous && (WizardMode || Verbose)) {
397 char buf[64];
398 warning("Ignoring %s - see 4229104 or 6499219",
399 os::exception_name(sig, buf, sizeof(buf)));
400
401 }
402 return true;
403 }
404 }
405
406 JavaThread* thread = NULL;
407 VMThread* vmthread = NULL;
408
409 if (os::Solaris::signal_handlers_are_installed) {
410 if (t != NULL ){
411 if(t->is_Java_thread()) {
412 thread = (JavaThread*)t;
413 }
414 else if(t->is_VM_thread()){
415 vmthread = (VMThread *)t;
416 }
417 }
418 }
419
420 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
421
422 if (sig == os::Solaris::SIGasync()) {
423 if(thread){
424 OSThread::InterruptArguments args(thread, uc);
425 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
426 return true;
427 }
428 else if(vmthread){
429 OSThread::InterruptArguments args(vmthread, uc);
430 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
431 return true;
432 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
433 return true;
434 } else {
435 // If os::Solaris::SIGasync not chained, and this is a non-vm and
436 // non-java thread
437 return true;
438 }
439 }
440
441 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
442 // can't decode this kind of signal
443 info = NULL;
444 } else {
445 assert(sig == info->si_signo, "bad siginfo");
446 }
447
448 // decide if this trap can be handled by a stub
449 address stub = NULL;
450
451 address pc = NULL;
452
453 //%note os_trap_1
454 if (info != NULL && uc != NULL && thread != NULL) {
455 // factor me: getPCfromContext
456 pc = (address) uc->uc_mcontext.gregs[REG_PC];
457
458 // SafeFetch32() support
459 if (pc == (address) Fetch32PFI) {
460 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
461 return true ;
462 }
463 #ifdef AMD64
464 if (pc == (address) FetchNPFI) {
465 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ;
466 return true ;
467 }
468 #endif // AMD64
469
470 // Handle ALL stack overflow variations here
471 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
472 address addr = (address) info->si_addr;
473 if (thread->in_stack_yellow_zone(addr)) {
474 thread->disable_stack_yellow_zone();
475 if (thread->thread_state() == _thread_in_Java) {
476 // Throw a stack overflow exception. Guard pages will be reenabled
477 // while unwinding the stack.
478 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
479 } else {
480 // Thread was in the vm or native code. Return and try to finish.
481 return true;
482 }
483 } else if (thread->in_stack_red_zone(addr)) {
484 // Fatal red zone violation. Disable the guard pages and fall through
485 // to handle_unexpected_exception way down below.
486 thread->disable_stack_red_zone();
487 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
488 }
489 }
490
491 if (thread->thread_state() == _thread_in_vm) {
492 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
493 stub = StubRoutines::handler_for_unsafe_access();
494 }
495 }
496
497 if (thread->thread_state() == _thread_in_Java) {
498 // Support Safepoint Polling
499 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
500 stub = SharedRuntime::get_poll_stub(pc);
501 }
502 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
503 // BugId 4454115: A read from a MappedByteBuffer can fault
504 // here if the underlying file has been truncated.
505 // Do not crash the VM in such a case.
506 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
507 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
508 if (nm != NULL && nm->has_unsafe_access()) {
509 stub = StubRoutines::handler_for_unsafe_access();
510 }
511 }
512 else
513 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
514 // integer divide by zero
515 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
516 }
517 #ifndef AMD64
518 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
519 // floating-point divide by zero
520 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
521 }
522 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
523 // The encoding of D2I in i486.ad can cause an exception prior
524 // to the fist instruction if there was an invalid operation
525 // pending. We want to dismiss that exception. From the win_32
526 // side it also seems that if it really was the fist causing
527 // the exception that we do the d2i by hand with different
528 // rounding. Seems kind of weird. QQQ TODO
529 // Note that we take the exception at the NEXT floating point instruction.
530 if (pc[0] == 0xDB) {
531 assert(pc[0] == 0xDB, "not a FIST opcode");
532 assert(pc[1] == 0x14, "not a FIST opcode");
533 assert(pc[2] == 0x24, "not a FIST opcode");
534 return true;
535 } else {
536 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
537 assert(pc[-2] == 0x14, "not an flt invalid opcode");
538 assert(pc[-1] == 0x24, "not an flt invalid opcode");
539 }
540 }
541 else if (sig == SIGFPE ) {
542 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
543 }
544 #endif // !AMD64
545
546 // QQQ It doesn't seem that we need to do this on x86 because we should be able
547 // to return properly from the handler without this extra stuff on the back side.
548
549 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
550 // Determination of interpreter/vtable stub/compiled code null exception
551 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
552 }
553 }
554
555 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
556 // and the heap gets shrunk before the field access.
557 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
558 address addr = JNI_FastGetField::find_slowcase_pc(pc);
559 if (addr != (address)-1) {
560 stub = addr;
561 }
562 }
563
564 // Check to see if we caught the safepoint code in the
565 // process of write protecting the memory serialization page.
566 // It write enables the page immediately after protecting it
567 // so we can just return to retry the write.
568 if ((sig == SIGSEGV) &&
569 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
570 // Block current thread until the memory serialize page permission restored.
571 os::block_on_serialize_page_trap();
572 return true;
573 }
574 }
575
576 // Execution protection violation
577 //
578 // Preventative code for future versions of Solaris which may
579 // enable execution protection when running the 32-bit VM on AMD64.
580 //
581 // This should be kept as the last step in the triage. We don't
582 // have a dedicated trap number for a no-execute fault, so be
583 // conservative and allow other handlers the first shot.
584 //
585 // Note: We don't test that info->si_code == SEGV_ACCERR here.
586 // this si_code is so generic that it is almost meaningless; and
587 // the si_code for this condition may change in the future.
588 // Furthermore, a false-positive should be harmless.
589 if (UnguardOnExecutionViolation > 0 &&
590 (sig == SIGSEGV || sig == SIGBUS) &&
591 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
592 int page_size = os::vm_page_size();
593 address addr = (address) info->si_addr;
594 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
595 // Make sure the pc and the faulting address are sane.
596 //
597 // If an instruction spans a page boundary, and the page containing
598 // the beginning of the instruction is executable but the following
599 // page is not, the pc and the faulting address might be slightly
600 // different - we still want to unguard the 2nd page in this case.
601 //
602 // 15 bytes seems to be a (very) safe value for max instruction size.
603 bool pc_is_near_addr =
604 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
605 bool instr_spans_page_boundary =
606 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
607 (intptr_t) page_size) > 0);
608
609 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
610 static volatile address last_addr =
611 (address) os::non_memory_address_word();
612
613 // In conservative mode, don't unguard unless the address is in the VM
614 if (addr != last_addr &&
615 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
616
617 // Make memory rwx and retry
618 address page_start =
619 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
620 bool res = os::protect_memory((char*) page_start, page_size,
621 os::MEM_PROT_RWX);
622
623 if (PrintMiscellaneous && Verbose) {
624 char buf[256];
625 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
626 "at " INTPTR_FORMAT
627 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
628 page_start, (res ? "success" : "failed"), errno);
629 tty->print_raw_cr(buf);
630 }
631 stub = pc;
632
633 // Set last_addr so if we fault again at the same address, we don't end
634 // up in an endless loop.
635 //
636 // There are two potential complications here. Two threads trapping at
637 // the same address at the same time could cause one of the threads to
638 // think it already unguarded, and abort the VM. Likely very rare.
639 //
640 // The other race involves two threads alternately trapping at
641 // different addresses and failing to unguard the page, resulting in
642 // an endless loop. This condition is probably even more unlikely than
643 // the first.
644 //
645 // Although both cases could be avoided by using locks or thread local
646 // last_addr, these solutions are unnecessary complication: this
647 // handler is a best-effort safety net, not a complete solution. It is
648 // disabled by default and should only be used as a workaround in case
649 // we missed any no-execute-unsafe VM code.
650
651 last_addr = addr;
652 }
653 }
654 }
655
656 if (stub != NULL) {
657 // save all thread context in case we need to restore it
658
659 if (thread != NULL) thread->set_saved_exception_pc(pc);
660 // 12/02/99: On Sparc it appears that the full context is also saved
661 // but as yet, no one looks at or restores that saved context
662 // factor me: setPC
663 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub;
664 return true;
665 }
666
667 // signal-chaining
668 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
669 return true;
670 }
671
672 #ifndef AMD64
673 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
674 // Handle an undefined selector caused by an attempt to assign
675 // fs in libthread getipriptr(). With the current libthread design every 512
676 // thread creations the LDT for a private thread data structure is extended
677 // and thre is a hazard that and another thread attempting a thread creation
678 // will use a stale LDTR that doesn't reflect the structure's growth,
679 // causing a GP fault.
680 // Enforce the probable limit of passes through here to guard against an
681 // infinite loop if some other move to fs caused the GP fault. Note that
682 // this loop counter is ultimately a heuristic as it is possible for
683 // more than one thread to generate this fault at a time in an MP system.
684 // In the case of the loop count being exceeded or if the poll fails
685 // just fall through to a fatal error.
686 // If there is some other source of T_GPFLT traps and the text at EIP is
687 // unreadable this code will loop infinitely until the stack is exausted.
688 // The key to diagnosis in this case is to look for the bottom signal handler
689 // frame.
690
691 if(! IgnoreLibthreadGPFault) {
692 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
693 const unsigned char *p =
694 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
695
696 // Expected instruction?
697
698 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
699
700 Atomic::inc(&ldtr_refresh);
701
702 // Infinite loop?
703
704 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
705
706 // No, force scheduling to get a fresh view of the LDTR
707
708 if(poll(NULL, 0, 10) == 0) {
709
710 // Retry the move
711
712 return false;
713 }
714 }
715 }
716 }
717 }
718 #endif // !AMD64
719
720 if (!abort_if_unrecognized) {
721 // caller wants another chance, so give it to him
722 return false;
723 }
724
725 if (!os::Solaris::libjsig_is_loaded) {
726 struct sigaction oldAct;
727 sigaction(sig, (struct sigaction *)0, &oldAct);
728 if (oldAct.sa_sigaction != signalHandler) {
729 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
730 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
731 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
732 }
733 }
734
735 if (pc == NULL && uc != NULL) {
736 pc = (address) uc->uc_mcontext.gregs[REG_PC];
737 }
738
739 // unmask current signal
740 sigset_t newset;
741 sigemptyset(&newset);
742 sigaddset(&newset, sig);
743 sigprocmask(SIG_UNBLOCK, &newset, NULL);
744
745 // Determine which sort of error to throw. Out of swap may signal
746 // on the thread stack, which could get a mapping error when touched.
747 address addr = (address) info->si_addr;
748 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) {
749 vm_exit_out_of_memory(0, "Out of swap space to map in thread stack.");
750 }
751
752 VMError err(t, sig, pc, info, ucVoid);
753 err.report_and_die();
754
755 ShouldNotReachHere();
756 }
757
758 void os::print_context(outputStream *st, void *context) {
759 if (context == NULL) return;
760
761 ucontext_t *uc = (ucontext_t*)context;
762 st->print_cr("Registers:");
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 #else
787 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
788 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
789 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
790 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
791 st->cr();
792 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
793 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
794 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
795 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
796 st->cr();
797 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
798 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
799 #endif // AMD64
800 st->cr();
801 st->cr();
802
803 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
804 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
805 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
806 st->cr();
807
808 // Note: it may be unsafe to inspect memory near pc. For example, pc may
809 // point to garbage if entry point in an nmethod is corrupted. Leave
810 // this at the end, and hope for the best.
811 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
812 address pc = epc.pc();
813 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
814 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
815 }
816
817 void os::print_register_info(outputStream *st, void *context) {
818 if (context == NULL) return;
819
820 ucontext_t *uc = (ucontext_t*)context;
821
822 st->print_cr("Register to memory mapping:");
823 st->cr();
824
825 // this is horrendously verbose but the layout of the registers in the
826 // context does not match how we defined our abstract Register set, so
827 // we can't just iterate through the gregs area
828
829 // this is only for the "general purpose" registers
830
831 #ifdef AMD64
832 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
833 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
834 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
835 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
836 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
837 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]);
838 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
839 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
840 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]);
841 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]);
842 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]);
843 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]);
844 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]);
845 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]);
846 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]);
847 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]);
848 #else
849 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]);
850 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]);
851 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]);
852 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]);
853 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]);
854 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]);
855 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]);
856 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]);
857 #endif
858
859 st->cr();
860 }
861
862
863 #ifdef AMD64
864 void os::Solaris::init_thread_fpu_state(void) {
865 // Nothing to do
866 }
867 #else
868 // From solaris_i486.s
869 extern "C" void fixcw();
870
871 void os::Solaris::init_thread_fpu_state(void) {
872 // Set fpu to 53 bit precision. This happens too early to use a stub.
873 fixcw();
874 }
875
876 // These routines are the initial value of atomic_xchg_entry(),
877 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
878 // until initialization is complete.
879 // TODO - replace with .il implementation when compiler supports it.
880
881 typedef jint xchg_func_t (jint, volatile jint*);
882 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
883 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
884 typedef jint add_func_t (jint, volatile jint*);
885
886 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
887 // try to use the stub:
888 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
889
890 if (func != NULL) {
891 os::atomic_xchg_func = func;
892 return (*func)(exchange_value, dest);
893 }
894 assert(Threads::number_of_threads() == 0, "for bootstrap only");
895
896 jint old_value = *dest;
897 *dest = exchange_value;
898 return old_value;
899 }
900
901 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
902 // try to use the stub:
903 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
904
905 if (func != NULL) {
906 os::atomic_cmpxchg_func = func;
907 return (*func)(exchange_value, dest, compare_value);
908 }
909 assert(Threads::number_of_threads() == 0, "for bootstrap only");
910
911 jint old_value = *dest;
912 if (old_value == compare_value)
913 *dest = exchange_value;
914 return old_value;
915 }
916
917 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
918 // try to use the stub:
919 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
920
921 if (func != NULL) {
922 os::atomic_cmpxchg_long_func = func;
923 return (*func)(exchange_value, dest, compare_value);
924 }
925 assert(Threads::number_of_threads() == 0, "for bootstrap only");
926
927 jlong old_value = *dest;
928 if (old_value == compare_value)
929 *dest = exchange_value;
930 return old_value;
931 }
932
933 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
934 // try to use the stub:
935 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
936
937 if (func != NULL) {
938 os::atomic_add_func = func;
939 return (*func)(add_value, dest);
940 }
941 assert(Threads::number_of_threads() == 0, "for bootstrap only");
942
943 return (*dest) += add_value;
944 }
945
946 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
947 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
948 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
949 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
950
951 extern "C" void _solaris_raw_setup_fpu(address ptr);
952 void os::setup_fpu() {
953 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
954 _solaris_raw_setup_fpu(fpu_cntrl);
955 }
956 #endif // AMD64