1 /*
2 * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // no precompiled headers
26 #include "asm/macroAssembler.hpp"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "jvm_solaris.h"
34 #include "memory/allocation.inline.hpp"
35 #include "mutex_solaris.inline.hpp"
36 #include "os_share_solaris.hpp"
37 #include "prims/jniFastGetField.hpp"
38 #include "prims/jvm.h"
39 #include "prims/jvm_misc.hpp"
40 #include "runtime/arguments.hpp"
41 #include "runtime/extendedPC.hpp"
42 #include "runtime/frame.inline.hpp"
43 #include "runtime/interfaceSupport.hpp"
44 #include "runtime/java.hpp"
45 #include "runtime/javaCalls.hpp"
46 #include "runtime/mutexLocker.hpp"
47 #include "runtime/osThread.hpp"
48 #include "runtime/sharedRuntime.hpp"
49 #include "runtime/stubRoutines.hpp"
50 #include "runtime/thread.inline.hpp"
51 #include "runtime/timer.hpp"
52 #include "utilities/events.hpp"
53 #include "utilities/vmError.hpp"
54
55 // put OS-includes here
56 # include <sys/types.h>
57 # include <sys/mman.h>
58 # include <pthread.h>
59 # include <signal.h>
60 # include <setjmp.h>
61 # include <errno.h>
62 # include <dlfcn.h>
63 # include <stdio.h>
64 # include <unistd.h>
65 # include <sys/resource.h>
66 # include <thread.h>
67 # include <sys/stat.h>
68 # include <sys/time.h>
69 # include <sys/filio.h>
70 # include <sys/utsname.h>
71 # include <sys/systeminfo.h>
72 # include <sys/socket.h>
73 # include <sys/trap.h>
74 # include <sys/lwp.h>
75 # include <pwd.h>
76 # include <poll.h>
77 # include <sys/lwp.h>
78 # include <procfs.h> // see comment in <sys/procfs.h>
79
80 #ifndef AMD64
81 // QQQ seems useless at this point
82 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
83 #endif // AMD64
84 # include <sys/procfs.h> // see comment in <sys/procfs.h>
85
86
87 #define MAX_PATH (2 * K)
88
89 // Minimum stack size for the VM. It's easier to document a constant value
90 // but it's different for x86 and sparc because the page sizes are different.
91 #ifdef AMD64
92 size_t os::Solaris::min_stack_allowed = 224*K;
93 #define REG_SP REG_RSP
94 #define REG_PC REG_RIP
95 #define REG_FP REG_RBP
96 #else
97 size_t os::Solaris::min_stack_allowed = 64*K;
98 #define REG_SP UESP
99 #define REG_PC EIP
100 #define REG_FP EBP
101 // 4900493 counter to prevent runaway LDTR refresh attempt
102
103 static volatile int ldtr_refresh = 0;
104 // the libthread instruction that faults because of the stale LDTR
105
106 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
107 };
108 #endif // AMD64
109
110 char* os::non_memory_address_word() {
111 // Must never look like an address returned by reserve_memory,
112 // even in its subfields (as defined by the CPU immediate fields,
113 // if the CPU splits constants across multiple instructions).
114 return (char*) -1;
115 }
116
117 //
118 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
119 // There are issues with libthread giving out uc_links for different threads
120 // on the same uc_link chain and bad or circular links.
121 //
122 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
123 if (valid >= suspect ||
124 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
125 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
126 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
127 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
128 return false;
129 }
130
131 if (thread->is_Java_thread()) {
132 if (!valid_stack_address(thread, (address)suspect)) {
133 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
134 return false;
135 }
136 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
137 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
138 return false;
139 }
140 }
141 return true;
142 }
143
144 // We will only follow one level of uc_link since there are libthread
145 // issues with ucontext linking and it is better to be safe and just
146 // let caller retry later.
147 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
148 ucontext_t *uc) {
149
150 ucontext_t *retuc = NULL;
151
152 if (uc != NULL) {
153 if (uc->uc_link == NULL) {
154 // cannot validate without uc_link so accept current ucontext
155 retuc = uc;
156 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
157 // first ucontext is valid so try the next one
158 uc = uc->uc_link;
159 if (uc->uc_link == NULL) {
160 // cannot validate without uc_link so accept current ucontext
161 retuc = uc;
162 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
163 // the ucontext one level down is also valid so return it
164 retuc = uc;
165 }
166 }
167 }
168 return retuc;
169 }
170
171 // Assumes ucontext is valid
172 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
173 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
174 }
175
176 // Assumes ucontext is valid
177 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
178 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
179 }
180
181 // Assumes ucontext is valid
182 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
183 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
184 }
185
186 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
187 // is currently interrupted by SIGPROF.
188 //
189 // The difference between this and os::fetch_frame_from_context() is that
190 // here we try to skip nested signal frames.
191 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
192 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
193
194 assert(thread != NULL, "just checking");
195 assert(ret_sp != NULL, "just checking");
196 assert(ret_fp != NULL, "just checking");
197
198 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
199 return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
200 }
201
202 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
203 intptr_t** ret_sp, intptr_t** ret_fp) {
204
205 ExtendedPC epc;
206 ucontext_t *uc = (ucontext_t*)ucVoid;
207
208 if (uc != NULL) {
209 epc = os::Solaris::ucontext_get_ExtendedPC(uc);
210 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
211 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc);
212 } else {
213 // construct empty ExtendedPC for return value checking
214 epc = ExtendedPC(NULL);
215 if (ret_sp) *ret_sp = (intptr_t *)NULL;
216 if (ret_fp) *ret_fp = (intptr_t *)NULL;
217 }
218
219 return epc;
220 }
221
222 frame os::fetch_frame_from_context(void* ucVoid) {
223 intptr_t* sp;
224 intptr_t* fp;
225 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
226 return frame(sp, fp, epc.pc());
227 }
228
229 frame os::get_sender_for_C_frame(frame* fr) {
230 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
231 }
232
233 extern "C" intptr_t *_get_current_sp(); // in .il file
234
235 address os::current_stack_pointer() {
236 return (address)_get_current_sp();
237 }
238
239 extern "C" intptr_t *_get_current_fp(); // in .il file
240
241 frame os::current_frame() {
242 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
243 frame myframe((intptr_t*)os::current_stack_pointer(),
244 (intptr_t*)fp,
245 CAST_FROM_FN_PTR(address, os::current_frame));
246 if (os::is_first_C_frame(&myframe)) {
247 // stack is not walkable
248 frame ret; // This will be a null useless frame
249 return ret;
250 } else {
251 return os::get_sender_for_C_frame(&myframe);
252 }
253 }
254
255 // This is a simple callback that just fetches a PC for an interrupted thread.
256 // The thread need not be suspended and the fetched PC is just a hint.
257 // This one is currently used for profiling the VMThread ONLY!
258
259 // Must be synchronous
260 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {
261 Thread* thread = args->thread();
262 ucontext_t* uc = args->ucontext();
263 intptr_t* sp;
264
265 assert(ProfileVM && thread->is_VM_thread(), "just checking");
266
267 ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);
268 _addr = new_addr;
269 }
270
271 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
272 char lwpstatusfile[PROCFILE_LENGTH];
273 int lwpfd, err;
274
275 if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
276 return (err);
277 if (*flags == TRS_LWPID) {
278 sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
279 *lwp);
280 if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
281 perror("thr_mutator_status: open lwpstatus");
282 return (EINVAL);
283 }
284 if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
285 sizeof (lwpstatus_t)) {
286 perror("thr_mutator_status: read lwpstatus");
287 (void) close(lwpfd);
288 return (EINVAL);
289 }
290 (void) close(lwpfd);
291 }
292 return (0);
293 }
294
295 #ifndef AMD64
296
297 // Detecting SSE support by OS
298 // From solaris_i486.s
299 extern "C" bool sse_check();
300 extern "C" bool sse_unavailable();
301
302 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
303 static int sse_status = SSE_UNKNOWN;
304
305
306 static void check_for_sse_support() {
307 if (!VM_Version::supports_sse()) {
308 sse_status = SSE_NOT_SUPPORTED;
309 return;
310 }
311 // looking for _sse_hw in libc.so, if it does not exist or
312 // the value (int) is 0, OS has no support for SSE
313 int *sse_hwp;
314 void *h;
315
316 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
317 //open failed, presume no support for SSE
318 sse_status = SSE_NOT_SUPPORTED;
319 return;
320 }
321 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
322 sse_status = SSE_NOT_SUPPORTED;
323 } else if (*sse_hwp == 0) {
324 sse_status = SSE_NOT_SUPPORTED;
325 }
326 dlclose(h);
327
328 if (sse_status == SSE_UNKNOWN) {
329 bool (*try_sse)() = (bool (*)())sse_check;
330 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
331 }
332
333 }
334
335 #endif // AMD64
336
337 bool os::supports_sse() {
338 #ifdef AMD64
339 return true;
340 #else
341 if (sse_status == SSE_UNKNOWN)
342 check_for_sse_support();
343 return sse_status == SSE_SUPPORTED;
344 #endif // AMD64
345 }
346
347 bool os::is_allocatable(size_t bytes) {
348 #ifdef AMD64
349 return true;
350 #else
351
352 if (bytes < 2 * G) {
353 return true;
354 }
355
356 char* addr = reserve_memory(bytes, NULL);
357
358 if (addr != NULL) {
359 release_memory(addr, bytes);
360 }
361
362 return addr != NULL;
363 #endif // AMD64
364
365 }
366
367 extern "C" void Fetch32PFI () ;
368 extern "C" void Fetch32Resume () ;
369 #ifdef AMD64
370 extern "C" void FetchNPFI () ;
371 extern "C" void FetchNResume () ;
372 #endif // AMD64
373
374 extern "C" JNIEXPORT int
375 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid,
376 int abort_if_unrecognized) {
377 ucontext_t* uc = (ucontext_t*) ucVoid;
378
379 #ifndef AMD64
380 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
381 // the SSE instruction faulted. supports_sse() need return false.
382 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
383 return true;
384 }
385 #endif // !AMD64
386
387 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
388
389 SignalHandlerMark shm(t);
390
391 if(sig == SIGPIPE || sig == SIGXFSZ) {
392 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
393 return true;
394 } else {
395 if (PrintMiscellaneous && (WizardMode || Verbose)) {
396 char buf[64];
397 warning("Ignoring %s - see 4229104 or 6499219",
398 os::exception_name(sig, buf, sizeof(buf)));
399
400 }
401 return true;
402 }
403 }
404
405 JavaThread* thread = NULL;
406 VMThread* vmthread = NULL;
407
408 if (os::Solaris::signal_handlers_are_installed) {
409 if (t != NULL ){
410 if(t->is_Java_thread()) {
411 thread = (JavaThread*)t;
412 }
413 else if(t->is_VM_thread()){
414 vmthread = (VMThread *)t;
415 }
416 }
417 }
418
419 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
420
421 if (sig == os::Solaris::SIGasync()) {
422 if(thread){
423 OSThread::InterruptArguments args(thread, uc);
424 thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
425 return true;
426 }
427 else if(vmthread){
428 OSThread::InterruptArguments args(vmthread, uc);
429 vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
430 return true;
431 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
432 return true;
433 } else {
434 // If os::Solaris::SIGasync not chained, and this is a non-vm and
435 // non-java thread
436 return true;
437 }
438 }
439
440 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
441 // can't decode this kind of signal
442 info = NULL;
443 } else {
444 assert(sig == info->si_signo, "bad siginfo");
445 }
446
447 // decide if this trap can be handled by a stub
448 address stub = NULL;
449
450 address pc = NULL;
451
452 //%note os_trap_1
453 if (info != NULL && uc != NULL && thread != NULL) {
454 // factor me: getPCfromContext
455 pc = (address) uc->uc_mcontext.gregs[REG_PC];
456
457 // SafeFetch32() support
458 if (pc == (address) Fetch32PFI) {
459 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
460 return true ;
461 }
462 #ifdef AMD64
463 if (pc == (address) FetchNPFI) {
464 uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ;
465 return true ;
466 }
467 #endif // AMD64
468
469 // Handle ALL stack overflow variations here
470 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
471 address addr = (address) info->si_addr;
472 if (thread->in_stack_yellow_zone(addr)) {
473 thread->disable_stack_yellow_zone();
474 if (thread->thread_state() == _thread_in_Java) {
475 // Throw a stack overflow exception. Guard pages will be reenabled
476 // while unwinding the stack.
477 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
478 } else {
479 // Thread was in the vm or native code. Return and try to finish.
480 return true;
481 }
482 } else if (thread->in_stack_red_zone(addr)) {
483 // Fatal red zone violation. Disable the guard pages and fall through
484 // to handle_unexpected_exception way down below.
485 thread->disable_stack_red_zone();
486 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
487 }
488 }
489
490 if (thread->thread_state() == _thread_in_vm) {
491 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
492 stub = StubRoutines::handler_for_unsafe_access();
493 }
494 }
495
496 if (thread->thread_state() == _thread_in_Java) {
497 // Support Safepoint Polling
498 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
499 stub = SharedRuntime::get_poll_stub(pc);
500 }
501 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
502 // BugId 4454115: A read from a MappedByteBuffer can fault
503 // here if the underlying file has been truncated.
504 // Do not crash the VM in such a case.
505 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
506 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
507 if (nm != NULL && nm->has_unsafe_access()) {
508 stub = StubRoutines::handler_for_unsafe_access();
509 }
510 }
511 else
512 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
513 // integer divide by zero
514 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
515 }
516 #ifndef AMD64
517 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
518 // floating-point divide by zero
519 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
520 }
521 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
522 // The encoding of D2I in i486.ad can cause an exception prior
523 // to the fist instruction if there was an invalid operation
524 // pending. We want to dismiss that exception. From the win_32
525 // side it also seems that if it really was the fist causing
526 // the exception that we do the d2i by hand with different
527 // rounding. Seems kind of weird. QQQ TODO
528 // Note that we take the exception at the NEXT floating point instruction.
529 if (pc[0] == 0xDB) {
530 assert(pc[0] == 0xDB, "not a FIST opcode");
531 assert(pc[1] == 0x14, "not a FIST opcode");
532 assert(pc[2] == 0x24, "not a FIST opcode");
533 return true;
534 } else {
535 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
536 assert(pc[-2] == 0x14, "not an flt invalid opcode");
537 assert(pc[-1] == 0x24, "not an flt invalid opcode");
538 }
539 }
540 else if (sig == SIGFPE ) {
541 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
542 }
543 #endif // !AMD64
544
545 // QQQ It doesn't seem that we need to do this on x86 because we should be able
546 // to return properly from the handler without this extra stuff on the back side.
547
548 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
549 // Determination of interpreter/vtable stub/compiled code null exception
550 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
551 }
552 }
553
554 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
555 // and the heap gets shrunk before the field access.
556 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
557 address addr = JNI_FastGetField::find_slowcase_pc(pc);
558 if (addr != (address)-1) {
559 stub = addr;
560 }
561 }
562
563 // Check to see if we caught the safepoint code in the
564 // process of write protecting the memory serialization page.
565 // It write enables the page immediately after protecting it
566 // so we can just return to retry the write.
567 if ((sig == SIGSEGV) &&
568 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
569 // Block current thread until the memory serialize page permission restored.
570 os::block_on_serialize_page_trap();
571 return true;
572 }
573 }
574
575 // Execution protection violation
576 //
577 // Preventative code for future versions of Solaris which may
578 // enable execution protection when running the 32-bit VM on AMD64.
579 //
580 // This should be kept as the last step in the triage. We don't
581 // have a dedicated trap number for a no-execute fault, so be
582 // conservative and allow other handlers the first shot.
583 //
584 // Note: We don't test that info->si_code == SEGV_ACCERR here.
585 // this si_code is so generic that it is almost meaningless; and
586 // the si_code for this condition may change in the future.
587 // Furthermore, a false-positive should be harmless.
588 if (UnguardOnExecutionViolation > 0 &&
589 (sig == SIGSEGV || sig == SIGBUS) &&
590 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
591 int page_size = os::vm_page_size();
592 address addr = (address) info->si_addr;
593 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
594 // Make sure the pc and the faulting address are sane.
595 //
596 // If an instruction spans a page boundary, and the page containing
597 // the beginning of the instruction is executable but the following
598 // page is not, the pc and the faulting address might be slightly
599 // different - we still want to unguard the 2nd page in this case.
600 //
601 // 15 bytes seems to be a (very) safe value for max instruction size.
602 bool pc_is_near_addr =
603 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
604 bool instr_spans_page_boundary =
605 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
606 (intptr_t) page_size) > 0);
607
608 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
609 static volatile address last_addr =
610 (address) os::non_memory_address_word();
611
612 // In conservative mode, don't unguard unless the address is in the VM
613 if (addr != last_addr &&
614 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
615
616 // Make memory rwx and retry
617 address page_start =
618 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
619 bool res = os::protect_memory((char*) page_start, page_size,
620 os::MEM_PROT_RWX);
621
622 if (PrintMiscellaneous && Verbose) {
623 char buf[256];
624 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
625 "at " INTPTR_FORMAT
626 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
627 page_start, (res ? "success" : "failed"), errno);
628 tty->print_raw_cr(buf);
629 }
630 stub = pc;
631
632 // Set last_addr so if we fault again at the same address, we don't end
633 // up in an endless loop.
634 //
635 // There are two potential complications here. Two threads trapping at
636 // the same address at the same time could cause one of the threads to
637 // think it already unguarded, and abort the VM. Likely very rare.
638 //
639 // The other race involves two threads alternately trapping at
640 // different addresses and failing to unguard the page, resulting in
641 // an endless loop. This condition is probably even more unlikely than
642 // the first.
643 //
644 // Although both cases could be avoided by using locks or thread local
645 // last_addr, these solutions are unnecessary complication: this
646 // handler is a best-effort safety net, not a complete solution. It is
647 // disabled by default and should only be used as a workaround in case
648 // we missed any no-execute-unsafe VM code.
649
650 last_addr = addr;
651 }
652 }
653 }
654
655 if (stub != NULL) {
656 // save all thread context in case we need to restore it
657
658 if (thread != NULL) thread->set_saved_exception_pc(pc);
659 // 12/02/99: On Sparc it appears that the full context is also saved
660 // but as yet, no one looks at or restores that saved context
661 // factor me: setPC
662 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub;
663 return true;
664 }
665
666 // signal-chaining
667 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
668 return true;
669 }
670
671 #ifndef AMD64
672 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
673 // Handle an undefined selector caused by an attempt to assign
674 // fs in libthread getipriptr(). With the current libthread design every 512
675 // thread creations the LDT for a private thread data structure is extended
676 // and thre is a hazard that and another thread attempting a thread creation
677 // will use a stale LDTR that doesn't reflect the structure's growth,
678 // causing a GP fault.
679 // Enforce the probable limit of passes through here to guard against an
680 // infinite loop if some other move to fs caused the GP fault. Note that
681 // this loop counter is ultimately a heuristic as it is possible for
682 // more than one thread to generate this fault at a time in an MP system.
683 // In the case of the loop count being exceeded or if the poll fails
684 // just fall through to a fatal error.
685 // If there is some other source of T_GPFLT traps and the text at EIP is
686 // unreadable this code will loop infinitely until the stack is exausted.
687 // The key to diagnosis in this case is to look for the bottom signal handler
688 // frame.
689
690 if(! IgnoreLibthreadGPFault) {
691 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
692 const unsigned char *p =
693 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
694
695 // Expected instruction?
696
697 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
698
699 Atomic::inc(&ldtr_refresh);
700
701 // Infinite loop?
702
703 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
704
705 // No, force scheduling to get a fresh view of the LDTR
706
707 if(poll(NULL, 0, 10) == 0) {
708
709 // Retry the move
710
711 return false;
712 }
713 }
714 }
715 }
716 }
717 #endif // !AMD64
718
719 if (!abort_if_unrecognized) {
720 // caller wants another chance, so give it to him
721 return false;
722 }
723
724 if (!os::Solaris::libjsig_is_loaded) {
725 struct sigaction oldAct;
726 sigaction(sig, (struct sigaction *)0, &oldAct);
727 if (oldAct.sa_sigaction != signalHandler) {
728 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
729 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
730 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
731 }
732 }
733
734 if (pc == NULL && uc != NULL) {
735 pc = (address) uc->uc_mcontext.gregs[REG_PC];
736 }
737
738 // unmask current signal
739 sigset_t newset;
740 sigemptyset(&newset);
741 sigaddset(&newset, sig);
742 sigprocmask(SIG_UNBLOCK, &newset, NULL);
743
744 // Determine which sort of error to throw. Out of swap may signal
745 // on the thread stack, which could get a mapping error when touched.
746 address addr = (address) info->si_addr;
747 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) {
748 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack.");
749 }
750
751 VMError err(t, sig, pc, info, ucVoid);
752 err.report_and_die();
753
754 ShouldNotReachHere();
755 }
756
757 void os::print_context(outputStream *st, void *context) {
758 if (context == NULL) return;
759
760 ucontext_t *uc = (ucontext_t*)context;
761 st->print_cr("Registers:");
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 #else
786 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
787 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
788 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
789 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
790 st->cr();
791 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
792 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
793 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
794 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
795 st->cr();
796 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
797 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
798 #endif // AMD64
799 st->cr();
800 st->cr();
801
802 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
803 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
804 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
805 st->cr();
806
807 // Note: it may be unsafe to inspect memory near pc. For example, pc may
808 // point to garbage if entry point in an nmethod is corrupted. Leave
809 // this at the end, and hope for the best.
810 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
811 address pc = epc.pc();
812 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
813 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
814 }
815
816 void os::print_register_info(outputStream *st, void *context) {
817 if (context == NULL) return;
818
819 ucontext_t *uc = (ucontext_t*)context;
820
821 st->print_cr("Register to memory mapping:");
822 st->cr();
823
824 // this is horrendously verbose but the layout of the registers in the
825 // context does not match how we defined our abstract Register set, so
826 // we can't just iterate through the gregs area
827
828 // this is only for the "general purpose" registers
829
830 #ifdef AMD64
831 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
832 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
833 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
834 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
835 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
836 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]);
837 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
838 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
839 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]);
840 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]);
841 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]);
842 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]);
843 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]);
844 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]);
845 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]);
846 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]);
847 #else
848 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]);
849 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]);
850 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]);
851 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]);
852 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]);
853 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]);
854 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]);
855 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]);
856 #endif
857
858 st->cr();
859 }
860
861
862 #ifdef AMD64
863 void os::Solaris::init_thread_fpu_state(void) {
864 // Nothing to do
865 }
866 #else
867 // From solaris_i486.s
868 extern "C" void fixcw();
869
870 void os::Solaris::init_thread_fpu_state(void) {
871 // Set fpu to 53 bit precision. This happens too early to use a stub.
872 fixcw();
873 }
874
875 // These routines are the initial value of atomic_xchg_entry(),
876 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
877 // until initialization is complete.
878 // TODO - replace with .il implementation when compiler supports it.
879
880 typedef jint xchg_func_t (jint, volatile jint*);
881 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
882 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
883 typedef jint add_func_t (jint, volatile jint*);
884
885 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
886 // try to use the stub:
887 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
888
889 if (func != NULL) {
890 os::atomic_xchg_func = func;
891 return (*func)(exchange_value, dest);
892 }
893 assert(Threads::number_of_threads() == 0, "for bootstrap only");
894
895 jint old_value = *dest;
896 *dest = exchange_value;
897 return old_value;
898 }
899
900 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
901 // try to use the stub:
902 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
903
904 if (func != NULL) {
905 os::atomic_cmpxchg_func = func;
906 return (*func)(exchange_value, dest, compare_value);
907 }
908 assert(Threads::number_of_threads() == 0, "for bootstrap only");
909
910 jint old_value = *dest;
911 if (old_value == compare_value)
912 *dest = exchange_value;
913 return old_value;
914 }
915
916 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
917 // try to use the stub:
918 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
919
920 if (func != NULL) {
921 os::atomic_cmpxchg_long_func = func;
922 return (*func)(exchange_value, dest, compare_value);
923 }
924 assert(Threads::number_of_threads() == 0, "for bootstrap only");
925
926 jlong old_value = *dest;
927 if (old_value == compare_value)
928 *dest = exchange_value;
929 return old_value;
930 }
931
932 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
933 // try to use the stub:
934 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
935
936 if (func != NULL) {
937 os::atomic_add_func = func;
938 return (*func)(add_value, dest);
939 }
940 assert(Threads::number_of_threads() == 0, "for bootstrap only");
941
942 return (*dest) += add_value;
943 }
944
945 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
946 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
947 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
948 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
949
950 extern "C" void _solaris_raw_setup_fpu(address ptr);
951 void os::setup_fpu() {
952 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
953 _solaris_raw_setup_fpu(fpu_cntrl);
954 }
955 #endif // AMD64
956
957 #ifndef PRODUCT
958 void os::verify_stack_alignment() {
959 #ifdef AMD64
960 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
961 #endif
962 }
963 #endif