1 /*
2 * Copyright (c) 1999, 2014, 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/atomic.inline.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/thread.inline.hpp"
52 #include "runtime/timer.hpp"
53 #include "utilities/events.hpp"
54 #include "utilities/vmError.hpp"
55
56 // put OS-includes here
57 # include <sys/types.h>
58 # include <sys/mman.h>
59 # include <pthread.h>
60 # include <signal.h>
61 # include <setjmp.h>
62 # include <errno.h>
63 # include <dlfcn.h>
64 # include <stdio.h>
65 # include <unistd.h>
66 # include <sys/resource.h>
67 # include <thread.h>
68 # include <sys/stat.h>
69 # include <sys/time.h>
70 # include <sys/filio.h>
71 # include <sys/utsname.h>
72 # include <sys/systeminfo.h>
73 # include <sys/socket.h>
74 # include <sys/trap.h>
75 # include <sys/lwp.h>
76 # include <pwd.h>
77 # include <poll.h>
78 # include <sys/lwp.h>
79 # include <procfs.h> // see comment in <sys/procfs.h>
80
81 #ifndef AMD64
82 // QQQ seems useless at this point
83 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
84 #endif // AMD64
85 # include <sys/procfs.h> // see comment in <sys/procfs.h>
86
87
88 #define MAX_PATH (2 * K)
89
90 // Minimum stack size for the VM. It's easier to document a constant value
91 // but it's different for x86 and sparc because the page sizes are different.
92 #ifdef AMD64
93 size_t os::Solaris::min_stack_allowed = 224*K;
94 #define REG_SP REG_RSP
95 #define REG_PC REG_RIP
96 #define REG_FP REG_RBP
97 #else
98 size_t os::Solaris::min_stack_allowed = 64*K;
99 #define REG_SP UESP
100 #define REG_PC EIP
101 #define REG_FP EBP
102 // 4900493 counter to prevent runaway LDTR refresh attempt
103
104 static volatile int ldtr_refresh = 0;
105 // the libthread instruction that faults because of the stale LDTR
106
107 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs
108 };
109 #endif // AMD64
110
111 char* os::non_memory_address_word() {
112 // Must never look like an address returned by reserve_memory,
113 // even in its subfields (as defined by the CPU immediate fields,
114 // if the CPU splits constants across multiple instructions).
115 return (char*) -1;
116 }
117
118 //
119 // Validate a ucontext retrieved from walking a uc_link of a ucontext.
120 // There are issues with libthread giving out uc_links for different threads
121 // on the same uc_link chain and bad or circular links.
122 //
123 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
124 if (valid >= suspect ||
125 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
126 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
127 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
128 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
129 return false;
130 }
131
132 if (thread->is_Java_thread()) {
133 if (!valid_stack_address(thread, (address)suspect)) {
134 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
135 return false;
136 }
137 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) {
138 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
139 return false;
140 }
141 }
142 return true;
143 }
144
145 // We will only follow one level of uc_link since there are libthread
146 // issues with ucontext linking and it is better to be safe and just
147 // let caller retry later.
148 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
149 ucontext_t *uc) {
150
151 ucontext_t *retuc = NULL;
152
153 if (uc != NULL) {
154 if (uc->uc_link == NULL) {
155 // cannot validate without uc_link so accept current ucontext
156 retuc = uc;
157 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
158 // first ucontext is valid so try the next one
159 uc = uc->uc_link;
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 // the ucontext one level down is also valid so return it
165 retuc = uc;
166 }
167 }
168 }
169 return retuc;
170 }
171
172 // Assumes ucontext is valid
173 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
174 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
175 }
176
177 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) {
178 uc->uc_mcontext.gregs [REG_PC] = (greg_t) pc;
179 }
180
181 // Assumes ucontext is valid
182 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
183 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
184 }
185
186 // Assumes ucontext is valid
187 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
188 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
189 }
190
191 address os::Solaris::ucontext_get_pc(ucontext_t *uc) {
192 return (address) uc->uc_mcontext.gregs[REG_PC];
193 }
194
195 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
196 // is currently interrupted by SIGPROF.
197 //
198 // The difference between this and os::fetch_frame_from_context() is that
199 // here we try to skip nested signal frames.
200 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
201 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
202
203 assert(thread != NULL, "just checking");
204 assert(ret_sp != NULL, "just checking");
205 assert(ret_fp != NULL, "just checking");
206
207 ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
208 return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
209 }
210
211 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
212 intptr_t** ret_sp, intptr_t** ret_fp) {
213
214 ExtendedPC epc;
215 ucontext_t *uc = (ucontext_t*)ucVoid;
216
217 if (uc != NULL) {
218 epc = os::Solaris::ucontext_get_ExtendedPC(uc);
219 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
220 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc);
221 } else {
222 // construct empty ExtendedPC for return value checking
223 epc = ExtendedPC(NULL);
224 if (ret_sp) *ret_sp = (intptr_t *)NULL;
225 if (ret_fp) *ret_fp = (intptr_t *)NULL;
226 }
227
228 return epc;
229 }
230
231 frame os::fetch_frame_from_context(void* ucVoid) {
232 intptr_t* sp;
233 intptr_t* fp;
234 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
235 return frame(sp, fp, epc.pc());
236 }
237
238 frame os::get_sender_for_C_frame(frame* fr) {
239 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
240 }
241
242 extern "C" intptr_t *_get_current_sp(); // in .il file
243
244 address os::current_stack_pointer() {
245 return (address)_get_current_sp();
246 }
247
248 extern "C" intptr_t *_get_current_fp(); // in .il file
249
250 frame os::current_frame() {
251 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
252 frame myframe((intptr_t*)os::current_stack_pointer(),
253 (intptr_t*)fp,
254 CAST_FROM_FN_PTR(address, os::current_frame));
255 if (os::is_first_C_frame(&myframe)) {
256 // stack is not walkable
257 frame ret; // This will be a null useless frame
258 return ret;
259 } else {
260 return os::get_sender_for_C_frame(&myframe);
261 }
262 }
263
264 #ifndef AMD64
265
266 // Detecting SSE support by OS
267 // From solaris_i486.s
268 extern "C" bool sse_check();
269 extern "C" bool sse_unavailable();
270
271 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
272 static int sse_status = SSE_UNKNOWN;
273
274
275 static void check_for_sse_support() {
276 if (!VM_Version::supports_sse()) {
277 sse_status = SSE_NOT_SUPPORTED;
278 return;
279 }
280 // looking for _sse_hw in libc.so, if it does not exist or
281 // the value (int) is 0, OS has no support for SSE
282 int *sse_hwp;
283 void *h;
284
285 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
286 //open failed, presume no support for SSE
287 sse_status = SSE_NOT_SUPPORTED;
288 return;
289 }
290 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
291 sse_status = SSE_NOT_SUPPORTED;
292 } else if (*sse_hwp == 0) {
293 sse_status = SSE_NOT_SUPPORTED;
294 }
295 dlclose(h);
296
297 if (sse_status == SSE_UNKNOWN) {
298 bool (*try_sse)() = (bool (*)())sse_check;
299 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
300 }
301
302 }
303
304 #endif // AMD64
305
306 bool os::supports_sse() {
307 #ifdef AMD64
308 return true;
309 #else
310 if (sse_status == SSE_UNKNOWN)
311 check_for_sse_support();
312 return sse_status == SSE_SUPPORTED;
313 #endif // AMD64
314 }
315
316 bool os::is_allocatable(size_t bytes) {
317 #ifdef AMD64
318 return true;
319 #else
320
321 if (bytes < 2 * G) {
322 return true;
323 }
324
325 char* addr = reserve_memory(bytes, NULL);
326
327 if (addr != NULL) {
328 release_memory(addr, bytes);
329 }
330
331 return addr != NULL;
332 #endif // AMD64
333
334 }
335
336 extern "C" JNIEXPORT int
337 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid,
338 int abort_if_unrecognized) {
339 ucontext_t* uc = (ucontext_t*) ucVoid;
340
341 #ifndef AMD64
342 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
343 // the SSE instruction faulted. supports_sse() need return false.
344 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
345 return true;
346 }
347 #endif // !AMD64
348
349 Thread* t = ThreadLocalStorage::get_thread_slow(); // slow & steady
350
351 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
352 // (no destructors can be run)
353 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
354
355 SignalHandlerMark shm(t);
356
357 if(sig == SIGPIPE || sig == SIGXFSZ) {
358 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
359 return true;
360 } else {
361 if (PrintMiscellaneous && (WizardMode || Verbose)) {
362 char buf[64];
363 warning("Ignoring %s - see 4229104 or 6499219",
364 os::exception_name(sig, buf, sizeof(buf)));
365
366 }
367 return true;
368 }
369 }
370
371 JavaThread* thread = NULL;
372 VMThread* vmthread = NULL;
373
374 if (os::Solaris::signal_handlers_are_installed) {
375 if (t != NULL ){
376 if(t->is_Java_thread()) {
377 thread = (JavaThread*)t;
378 }
379 else if(t->is_VM_thread()){
380 vmthread = (VMThread *)t;
381 }
382 }
383 }
384
385 guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
386
387 if (sig == os::Solaris::SIGasync()) {
388 if(thread || vmthread){
389 OSThread::SR_handler(t, uc);
390 return true;
391 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
392 return true;
393 } else {
394 // If os::Solaris::SIGasync not chained, and this is a non-vm and
395 // non-java thread
396 return true;
397 }
398 }
399
400 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
401 // can't decode this kind of signal
402 info = NULL;
403 } else {
404 assert(sig == info->si_signo, "bad siginfo");
405 }
406
407 // decide if this trap can be handled by a stub
408 address stub = NULL;
409
410 address pc = NULL;
411
412 //%note os_trap_1
413 if (info != NULL && uc != NULL && thread != NULL) {
414 // factor me: getPCfromContext
415 pc = (address) uc->uc_mcontext.gregs[REG_PC];
416
417 if (StubRoutines::is_safefetch_fault(pc)) {
418 os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
419 return true;
420 }
421
422 // Handle ALL stack overflow variations here
423 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
424 address addr = (address) info->si_addr;
425 if (thread->in_stack_yellow_zone(addr)) {
426 thread->disable_stack_yellow_zone();
427 if (thread->thread_state() == _thread_in_Java) {
428 // Throw a stack overflow exception. Guard pages will be reenabled
429 // while unwinding the stack.
430 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
431 } else {
432 // Thread was in the vm or native code. Return and try to finish.
433 return true;
434 }
435 } else if (thread->in_stack_red_zone(addr)) {
436 // Fatal red zone violation. Disable the guard pages and fall through
437 // to handle_unexpected_exception way down below.
438 thread->disable_stack_red_zone();
439 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
440 }
441 }
442
443 if ((sig == SIGSEGV) && VM_Version::is_cpuinfo_segv_addr(pc)) {
444 // Verify that OS save/restore AVX registers.
445 stub = VM_Version::cpuinfo_cont_addr();
446 }
447
448 if (thread->thread_state() == _thread_in_vm) {
449 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
450 stub = StubRoutines::handler_for_unsafe_access();
451 }
452 }
453
454 if (thread->thread_state() == _thread_in_Java) {
455 // Support Safepoint Polling
456 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
457 stub = SharedRuntime::get_poll_stub(pc);
458 }
459 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
460 // BugId 4454115: A read from a MappedByteBuffer can fault
461 // here if the underlying file has been truncated.
462 // Do not crash the VM in such a case.
463 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
464 if (cb != NULL) {
465 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
466 if (nm != NULL && nm->has_unsafe_access()) {
467 stub = StubRoutines::handler_for_unsafe_access();
468 }
469 }
470 }
471 else
472 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
473 // integer divide by zero
474 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
475 }
476 #ifndef AMD64
477 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
478 // floating-point divide by zero
479 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
480 }
481 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
482 // The encoding of D2I in i486.ad can cause an exception prior
483 // to the fist instruction if there was an invalid operation
484 // pending. We want to dismiss that exception. From the win_32
485 // side it also seems that if it really was the fist causing
486 // the exception that we do the d2i by hand with different
487 // rounding. Seems kind of weird. QQQ TODO
488 // Note that we take the exception at the NEXT floating point instruction.
489 if (pc[0] == 0xDB) {
490 assert(pc[0] == 0xDB, "not a FIST opcode");
491 assert(pc[1] == 0x14, "not a FIST opcode");
492 assert(pc[2] == 0x24, "not a FIST opcode");
493 return true;
494 } else {
495 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
496 assert(pc[-2] == 0x14, "not an flt invalid opcode");
497 assert(pc[-1] == 0x24, "not an flt invalid opcode");
498 }
499 }
500 else if (sig == SIGFPE ) {
501 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
502 }
503 #endif // !AMD64
504
505 // QQQ It doesn't seem that we need to do this on x86 because we should be able
506 // to return properly from the handler without this extra stuff on the back side.
507
508 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
509 // Determination of interpreter/vtable stub/compiled code null exception
510 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
511 }
512 }
513
514 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
515 // and the heap gets shrunk before the field access.
516 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
517 address addr = JNI_FastGetField::find_slowcase_pc(pc);
518 if (addr != (address)-1) {
519 stub = addr;
520 }
521 }
522
523 // Check to see if we caught the safepoint code in the
524 // process of write protecting the memory serialization page.
525 // It write enables the page immediately after protecting it
526 // so we can just return to retry the write.
527 if ((sig == SIGSEGV) &&
528 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
529 // Block current thread until the memory serialize page permission restored.
530 os::block_on_serialize_page_trap();
531 return true;
532 }
533 }
534
535 // Execution protection violation
536 //
537 // Preventative code for future versions of Solaris which may
538 // enable execution protection when running the 32-bit VM on AMD64.
539 //
540 // This should be kept as the last step in the triage. We don't
541 // have a dedicated trap number for a no-execute fault, so be
542 // conservative and allow other handlers the first shot.
543 //
544 // Note: We don't test that info->si_code == SEGV_ACCERR here.
545 // this si_code is so generic that it is almost meaningless; and
546 // the si_code for this condition may change in the future.
547 // Furthermore, a false-positive should be harmless.
548 if (UnguardOnExecutionViolation > 0 &&
549 (sig == SIGSEGV || sig == SIGBUS) &&
550 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
551 int page_size = os::vm_page_size();
552 address addr = (address) info->si_addr;
553 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
554 // Make sure the pc and the faulting address are sane.
555 //
556 // If an instruction spans a page boundary, and the page containing
557 // the beginning of the instruction is executable but the following
558 // page is not, the pc and the faulting address might be slightly
559 // different - we still want to unguard the 2nd page in this case.
560 //
561 // 15 bytes seems to be a (very) safe value for max instruction size.
562 bool pc_is_near_addr =
563 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
564 bool instr_spans_page_boundary =
565 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
566 (intptr_t) page_size) > 0);
567
568 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
569 static volatile address last_addr =
570 (address) os::non_memory_address_word();
571
572 // In conservative mode, don't unguard unless the address is in the VM
573 if (addr != last_addr &&
574 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
575
576 // Make memory rwx and retry
577 address page_start =
578 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
579 bool res = os::protect_memory((char*) page_start, page_size,
580 os::MEM_PROT_RWX);
581
582 if (PrintMiscellaneous && Verbose) {
583 char buf[256];
584 jio_snprintf(buf, sizeof(buf), "Execution protection violation "
585 "at " INTPTR_FORMAT
586 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
587 page_start, (res ? "success" : "failed"), errno);
588 tty->print_raw_cr(buf);
589 }
590 stub = pc;
591
592 // Set last_addr so if we fault again at the same address, we don't end
593 // up in an endless loop.
594 //
595 // There are two potential complications here. Two threads trapping at
596 // the same address at the same time could cause one of the threads to
597 // think it already unguarded, and abort the VM. Likely very rare.
598 //
599 // The other race involves two threads alternately trapping at
600 // different addresses and failing to unguard the page, resulting in
601 // an endless loop. This condition is probably even more unlikely than
602 // the first.
603 //
604 // Although both cases could be avoided by using locks or thread local
605 // last_addr, these solutions are unnecessary complication: this
606 // handler is a best-effort safety net, not a complete solution. It is
607 // disabled by default and should only be used as a workaround in case
608 // we missed any no-execute-unsafe VM code.
609
610 last_addr = addr;
611 }
612 }
613 }
614
615 if (stub != NULL) {
616 // save all thread context in case we need to restore it
617
618 if (thread != NULL) thread->set_saved_exception_pc(pc);
619 // 12/02/99: On Sparc it appears that the full context is also saved
620 // but as yet, no one looks at or restores that saved context
621 os::Solaris::ucontext_set_pc(uc, stub);
622 return true;
623 }
624
625 // signal-chaining
626 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
627 return true;
628 }
629
630 #ifndef AMD64
631 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
632 // Handle an undefined selector caused by an attempt to assign
633 // fs in libthread getipriptr(). With the current libthread design every 512
634 // thread creations the LDT for a private thread data structure is extended
635 // and thre is a hazard that and another thread attempting a thread creation
636 // will use a stale LDTR that doesn't reflect the structure's growth,
637 // causing a GP fault.
638 // Enforce the probable limit of passes through here to guard against an
639 // infinite loop if some other move to fs caused the GP fault. Note that
640 // this loop counter is ultimately a heuristic as it is possible for
641 // more than one thread to generate this fault at a time in an MP system.
642 // In the case of the loop count being exceeded or if the poll fails
643 // just fall through to a fatal error.
644 // If there is some other source of T_GPFLT traps and the text at EIP is
645 // unreadable this code will loop infinitely until the stack is exausted.
646 // The key to diagnosis in this case is to look for the bottom signal handler
647 // frame.
648
649 if(! IgnoreLibthreadGPFault) {
650 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
651 const unsigned char *p =
652 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
653
654 // Expected instruction?
655
656 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
657
658 Atomic::inc(&ldtr_refresh);
659
660 // Infinite loop?
661
662 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
663
664 // No, force scheduling to get a fresh view of the LDTR
665
666 if(poll(NULL, 0, 10) == 0) {
667
668 // Retry the move
669
670 return false;
671 }
672 }
673 }
674 }
675 }
676 #endif // !AMD64
677
678 if (!abort_if_unrecognized) {
679 // caller wants another chance, so give it to him
680 return false;
681 }
682
683 if (!os::Solaris::libjsig_is_loaded) {
684 struct sigaction oldAct;
685 sigaction(sig, (struct sigaction *)0, &oldAct);
686 if (oldAct.sa_sigaction != signalHandler) {
687 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
688 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
689 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
690 }
691 }
692
693 if (pc == NULL && uc != NULL) {
694 pc = (address) uc->uc_mcontext.gregs[REG_PC];
695 }
696
697 // unmask current signal
698 sigset_t newset;
699 sigemptyset(&newset);
700 sigaddset(&newset, sig);
701 sigprocmask(SIG_UNBLOCK, &newset, NULL);
702
703 // Determine which sort of error to throw. Out of swap may signal
704 // on the thread stack, which could get a mapping error when touched.
705 address addr = (address) info->si_addr;
706 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) {
707 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack.");
708 }
709
710 VMError::report_and_die(t, sig, pc, info, ucVoid);
711
712 ShouldNotReachHere();
713 return false;
714 }
715
716 void os::print_context(outputStream *st, void *context) {
717 if (context == NULL) return;
718
719 ucontext_t *uc = (ucontext_t*)context;
720 st->print_cr("Registers:");
721 #ifdef AMD64
722 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
723 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
724 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
725 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
726 st->cr();
727 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
728 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
729 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
730 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
731 st->cr();
732 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
733 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
734 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
735 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
736 st->cr();
737 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
738 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
739 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
740 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
741 st->cr();
742 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
743 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]);
744 #else
745 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
746 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
747 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
748 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
749 st->cr();
750 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
751 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
752 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
753 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
754 st->cr();
755 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
756 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
757 #endif // AMD64
758 st->cr();
759 st->cr();
760
761 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
762 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
763 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
764 st->cr();
765
766 // Note: it may be unsafe to inspect memory near pc. For example, pc may
767 // point to garbage if entry point in an nmethod is corrupted. Leave
768 // this at the end, and hope for the best.
769 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
770 address pc = epc.pc();
771 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
772 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
773 }
774
775 void os::print_register_info(outputStream *st, void *context) {
776 if (context == NULL) return;
777
778 ucontext_t *uc = (ucontext_t*)context;
779
780 st->print_cr("Register to memory mapping:");
781 st->cr();
782
783 // this is horrendously verbose but the layout of the registers in the
784 // context does not match how we defined our abstract Register set, so
785 // we can't just iterate through the gregs area
786
787 // this is only for the "general purpose" registers
788
789 #ifdef AMD64
790 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
791 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
792 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
793 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
794 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
795 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]);
796 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
797 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
798 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]);
799 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]);
800 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]);
801 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]);
802 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]);
803 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]);
804 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]);
805 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]);
806 #else
807 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]);
808 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]);
809 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]);
810 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]);
811 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]);
812 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]);
813 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]);
814 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]);
815 #endif
816
817 st->cr();
818 }
819
820
821 #ifdef AMD64
822 void os::Solaris::init_thread_fpu_state(void) {
823 // Nothing to do
824 }
825 #else
826 // From solaris_i486.s
827 extern "C" void fixcw();
828
829 void os::Solaris::init_thread_fpu_state(void) {
830 // Set fpu to 53 bit precision. This happens too early to use a stub.
831 fixcw();
832 }
833
834 // These routines are the initial value of atomic_xchg_entry(),
835 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
836 // until initialization is complete.
837 // TODO - replace with .il implementation when compiler supports it.
838
839 typedef jint xchg_func_t (jint, volatile jint*);
840 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
841 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
842 typedef jint add_func_t (jint, volatile jint*);
843
844 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
845 // try to use the stub:
846 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
847
848 if (func != NULL) {
849 os::atomic_xchg_func = func;
850 return (*func)(exchange_value, dest);
851 }
852 assert(Threads::number_of_threads() == 0, "for bootstrap only");
853
854 jint old_value = *dest;
855 *dest = exchange_value;
856 return old_value;
857 }
858
859 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
860 // try to use the stub:
861 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
862
863 if (func != NULL) {
864 os::atomic_cmpxchg_func = func;
865 return (*func)(exchange_value, dest, compare_value);
866 }
867 assert(Threads::number_of_threads() == 0, "for bootstrap only");
868
869 jint old_value = *dest;
870 if (old_value == compare_value)
871 *dest = exchange_value;
872 return old_value;
873 }
874
875 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
876 // try to use the stub:
877 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
878
879 if (func != NULL) {
880 os::atomic_cmpxchg_long_func = func;
881 return (*func)(exchange_value, dest, compare_value);
882 }
883 assert(Threads::number_of_threads() == 0, "for bootstrap only");
884
885 jlong old_value = *dest;
886 if (old_value == compare_value)
887 *dest = exchange_value;
888 return old_value;
889 }
890
891 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
892 // try to use the stub:
893 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
894
895 if (func != NULL) {
896 os::atomic_add_func = func;
897 return (*func)(add_value, dest);
898 }
899 assert(Threads::number_of_threads() == 0, "for bootstrap only");
900
901 return (*dest) += add_value;
902 }
903
904 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
905 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
906 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
907 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
908
909 extern "C" void _solaris_raw_setup_fpu(address ptr);
910 void os::setup_fpu() {
911 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
912 _solaris_raw_setup_fpu(fpu_cntrl);
913 }
914 #endif // AMD64
915
916 #ifndef PRODUCT
917 void os::verify_stack_alignment() {
918 #ifdef AMD64
919 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
920 #endif
921 }
922 #endif
923
924 int os::extra_bang_size_in_bytes() {
925 // JDK-8050147 requires the full cache line bang for x86.
926 return VM_Version::L1_line_size();
927 }