1 /*
2 * Copyright (c) 1999, 2016, 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/codeCache.hpp"
31 #include "code/icBuffer.hpp"
32 #include "code/vtableStubs.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_solaris.h"
35 #include "memory/allocation.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.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 <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, const ucontext_t* valid, const 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 const ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
148 const ucontext_t *uc) {
149
150 const 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(const ucontext_t *uc) {
173 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]);
174 }
175
176 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) {
177 uc->uc_mcontext.gregs [REG_PC] = (greg_t) pc;
178 }
179
180 // Assumes ucontext is valid
181 intptr_t* os::Solaris::ucontext_get_sp(const ucontext_t *uc) {
182 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
183 }
184
185 // Assumes ucontext is valid
186 intptr_t* os::Solaris::ucontext_get_fp(const ucontext_t *uc) {
187 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
188 }
189
190 address os::Solaris::ucontext_get_pc(const ucontext_t *uc) {
191 return (address) uc->uc_mcontext.gregs[REG_PC];
192 }
193
194 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
195 // is currently interrupted by SIGPROF.
196 //
197 // The difference between this and os::fetch_frame_from_context() is that
198 // here we try to skip nested signal frames.
199 // This method is also used for stack overflow signal handling.
200 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
201 const 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 const 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(const void* ucVoid,
212 intptr_t** ret_sp, intptr_t** ret_fp) {
213
214 ExtendedPC epc;
215 const ucontext_t *uc = (const 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(const 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::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) {
239 intptr_t* sp;
240 intptr_t* fp;
241 ExtendedPC epc = os::Solaris::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp);
242 return frame(sp, fp, epc.pc());
243 }
244
245 bool os::Solaris::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
246 address pc = (address) os::Solaris::ucontext_get_pc(uc);
247 if (Interpreter::contains(pc)) {
248 // interpreter performs stack banging after the fixed frame header has
249 // been generated while the compilers perform it before. To maintain
250 // semantic consistency between interpreted and compiled frames, the
251 // method returns the Java sender of the current frame.
252 *fr = os::fetch_frame_from_ucontext(thread, uc);
253 if (!fr->is_first_java_frame()) {
254 assert(fr->safe_for_sender(thread), "Safety check");
255 *fr = fr->java_sender();
256 }
257 } else {
258 // more complex code with compiled code
259 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
260 CodeBlob* cb = CodeCache::find_blob(pc);
261 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
262 // Not sure where the pc points to, fallback to default
263 // stack overflow handling
264 return false;
265 } else {
266 // in compiled code, the stack banging is performed just after the return pc
267 // has been pushed on the stack
268 intptr_t* fp = os::Solaris::ucontext_get_fp(uc);
269 intptr_t* sp = os::Solaris::ucontext_get_sp(uc);
270 *fr = frame(sp + 1, fp, (address)*sp);
271 if (!fr->is_java_frame()) {
272 assert(fr->safe_for_sender(thread), "Safety check");
273 *fr = fr->java_sender();
274 }
275 }
276 }
277 assert(fr->is_java_frame(), "Safety check");
278 return true;
279 }
280
281 frame os::get_sender_for_C_frame(frame* fr) {
282 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
283 }
284
285 extern "C" intptr_t *_get_current_sp(); // in .il file
286
287 address os::current_stack_pointer() {
288 return (address)_get_current_sp();
289 }
290
291 extern "C" intptr_t *_get_current_fp(); // in .il file
292
293 frame os::current_frame() {
294 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp
295 // fp is for os::current_frame. We want the fp for our caller.
296 frame myframe((intptr_t*)os::current_stack_pointer(),
297 (intptr_t*)fp,
298 CAST_FROM_FN_PTR(address, os::current_frame));
299 frame caller_frame = os::get_sender_for_C_frame(&myframe);
300
301 if (os::is_first_C_frame(&caller_frame)) {
302 // stack is not walkable
303 frame ret; // This will be a null useless frame
304 return ret;
305 } else {
306 // return frame for our caller's caller
307 return os::get_sender_for_C_frame(&caller_frame);
308 }
309 }
310
311 #ifndef AMD64
312
313 // Detecting SSE support by OS
314 // From solaris_i486.s
315 extern "C" bool sse_check();
316 extern "C" bool sse_unavailable();
317
318 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED};
319 static int sse_status = SSE_UNKNOWN;
320
321
322 static void check_for_sse_support() {
323 if (!VM_Version::supports_sse()) {
324 sse_status = SSE_NOT_SUPPORTED;
325 return;
326 }
327 // looking for _sse_hw in libc.so, if it does not exist or
328 // the value (int) is 0, OS has no support for SSE
329 int *sse_hwp;
330 void *h;
331
332 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) {
333 //open failed, presume no support for SSE
334 sse_status = SSE_NOT_SUPPORTED;
335 return;
336 }
337 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) {
338 sse_status = SSE_NOT_SUPPORTED;
339 } else if (*sse_hwp == 0) {
340 sse_status = SSE_NOT_SUPPORTED;
341 }
342 dlclose(h);
343
344 if (sse_status == SSE_UNKNOWN) {
345 bool (*try_sse)() = (bool (*)())sse_check;
346 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED;
347 }
348
349 }
350
351 #endif // AMD64
352
353 bool os::supports_sse() {
354 #ifdef AMD64
355 return true;
356 #else
357 if (sse_status == SSE_UNKNOWN)
358 check_for_sse_support();
359 return sse_status == SSE_SUPPORTED;
360 #endif // AMD64
361 }
362
363 bool os::is_allocatable(size_t bytes) {
364 #ifdef AMD64
365 return true;
366 #else
367
368 if (bytes < 2 * G) {
369 return true;
370 }
371
372 char* addr = reserve_memory(bytes, NULL);
373
374 if (addr != NULL) {
375 release_memory(addr, bytes);
376 }
377
378 return addr != NULL;
379 #endif // AMD64
380
381 }
382
383 extern "C" JNIEXPORT int
384 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid,
385 int abort_if_unrecognized) {
386 ucontext_t* uc = (ucontext_t*) ucVoid;
387
388 #ifndef AMD64
389 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) {
390 // the SSE instruction faulted. supports_sse() need return false.
391 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable;
392 return true;
393 }
394 #endif // !AMD64
395
396 Thread* t = Thread::current_or_null_safe();
397
398 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
399 // (no destructors can be run)
400 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
401
402 SignalHandlerMark shm(t);
403
404 if(sig == SIGPIPE || sig == SIGXFSZ) {
405 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
406 return true;
407 } else {
408 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
409 return true;
410 }
411 }
412
413 JavaThread* thread = NULL;
414 VMThread* vmthread = NULL;
415
416 if (os::Solaris::signal_handlers_are_installed) {
417 if (t != NULL ){
418 if(t->is_Java_thread()) {
419 thread = (JavaThread*)t;
420 }
421 else if(t->is_VM_thread()){
422 vmthread = (VMThread *)t;
423 }
424 }
425 }
426
427 if (sig == os::Solaris::SIGasync()) {
428 if(thread || vmthread){
429 OSThread::SR_handler(t, uc);
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 if (StubRoutines::is_safefetch_fault(pc)) {
458 os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
459 return true;
460 }
461
462 // Handle ALL stack overflow variations here
463 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
464 address addr = (address) info->si_addr;
465 if (thread->in_stack_yellow_reserved_zone(addr)) {
466 if (thread->thread_state() == _thread_in_Java) {
467 if (thread->in_stack_reserved_zone(addr)) {
468 frame fr;
469 if (os::Solaris::get_frame_at_stack_banging_point(thread, uc, &fr)) {
470 assert(fr.is_java_frame(), "Must be Java frame");
471 frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
472 if (activation.sp() != NULL) {
473 thread->disable_stack_reserved_zone();
474 if (activation.is_interpreted_frame()) {
475 thread->set_reserved_stack_activation((address)(
476 activation.fp() + frame::interpreter_frame_initial_sp_offset));
477 } else {
478 thread->set_reserved_stack_activation((address)activation.unextended_sp());
479 }
480 return true;
481 }
482 }
483 }
484 // Throw a stack overflow exception. Guard pages will be reenabled
485 // while unwinding the stack.
486 thread->disable_stack_yellow_reserved_zone();
487 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
488 } else {
489 // Thread was in the vm or native code. Return and try to finish.
490 thread->disable_stack_yellow_reserved_zone();
491 return true;
492 }
493 } else if (thread->in_stack_red_zone(addr)) {
494 // Fatal red zone violation. Disable the guard pages and fall through
495 // to handle_unexpected_exception way down below.
496 thread->disable_stack_red_zone();
497 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
498 }
499 }
500
501 if ((sig == SIGSEGV) && VM_Version::is_cpuinfo_segv_addr(pc)) {
502 // Verify that OS save/restore AVX registers.
503 stub = VM_Version::cpuinfo_cont_addr();
504 }
505
506 if (thread->thread_state() == _thread_in_vm) {
507 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
508 address next_pc = Assembler::locate_next_instruction(pc);
509 stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
510 }
511 }
512
513 if (thread->thread_state() == _thread_in_Java) {
514 // Support Safepoint Polling
515 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
516 stub = SharedRuntime::get_poll_stub(pc);
517 }
518 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
519 // BugId 4454115: A read from a MappedByteBuffer can fault
520 // here if the underlying file has been truncated.
521 // Do not crash the VM in such a case.
522 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
523 if (cb != NULL) {
524 CompiledMethod* nm = cb->as_compiled_method_or_null();
525 if (nm != NULL && nm->has_unsafe_access()) {
526 address next_pc = Assembler::locate_next_instruction(pc);
527 stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
528 }
529 }
530 }
531 else
532 if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
533 // integer divide by zero
534 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
535 }
536 #ifndef AMD64
537 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
538 // floating-point divide by zero
539 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
540 }
541 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) {
542 // The encoding of D2I in i486.ad can cause an exception prior
543 // to the fist instruction if there was an invalid operation
544 // pending. We want to dismiss that exception. From the win_32
545 // side it also seems that if it really was the fist causing
546 // the exception that we do the d2i by hand with different
547 // rounding. Seems kind of weird. QQQ TODO
548 // Note that we take the exception at the NEXT floating point instruction.
549 if (pc[0] == 0xDB) {
550 assert(pc[0] == 0xDB, "not a FIST opcode");
551 assert(pc[1] == 0x14, "not a FIST opcode");
552 assert(pc[2] == 0x24, "not a FIST opcode");
553 return true;
554 } else {
555 assert(pc[-3] == 0xDB, "not an flt invalid opcode");
556 assert(pc[-2] == 0x14, "not an flt invalid opcode");
557 assert(pc[-1] == 0x24, "not an flt invalid opcode");
558 }
559 }
560 else if (sig == SIGFPE ) {
561 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code);
562 }
563 #endif // !AMD64
564
565 // QQQ It doesn't seem that we need to do this on x86 because we should be able
566 // to return properly from the handler without this extra stuff on the back side.
567
568 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
569 // Determination of interpreter/vtable stub/compiled code null exception
570 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
571 }
572 }
573
574 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
575 // and the heap gets shrunk before the field access.
576 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
577 address addr = JNI_FastGetField::find_slowcase_pc(pc);
578 if (addr != (address)-1) {
579 stub = addr;
580 }
581 }
582
583 // Check to see if we caught the safepoint code in the
584 // process of write protecting the memory serialization page.
585 // It write enables the page immediately after protecting it
586 // so we can just return to retry the write.
587 if ((sig == SIGSEGV) &&
588 os::is_memory_serialize_page(thread, (address)info->si_addr)) {
589 // Block current thread until the memory serialize page permission restored.
590 os::block_on_serialize_page_trap();
591 return true;
592 }
593 }
594
595 // Execution protection violation
596 //
597 // Preventative code for future versions of Solaris which may
598 // enable execution protection when running the 32-bit VM on AMD64.
599 //
600 // This should be kept as the last step in the triage. We don't
601 // have a dedicated trap number for a no-execute fault, so be
602 // conservative and allow other handlers the first shot.
603 //
604 // Note: We don't test that info->si_code == SEGV_ACCERR here.
605 // this si_code is so generic that it is almost meaningless; and
606 // the si_code for this condition may change in the future.
607 // Furthermore, a false-positive should be harmless.
608 if (UnguardOnExecutionViolation > 0 &&
609 (sig == SIGSEGV || sig == SIGBUS) &&
610 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault
611 int page_size = os::vm_page_size();
612 address addr = (address) info->si_addr;
613 address pc = (address) uc->uc_mcontext.gregs[REG_PC];
614 // Make sure the pc and the faulting address are sane.
615 //
616 // If an instruction spans a page boundary, and the page containing
617 // the beginning of the instruction is executable but the following
618 // page is not, the pc and the faulting address might be slightly
619 // different - we still want to unguard the 2nd page in this case.
620 //
621 // 15 bytes seems to be a (very) safe value for max instruction size.
622 bool pc_is_near_addr =
623 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
624 bool instr_spans_page_boundary =
625 (align_size_down((intptr_t) pc ^ (intptr_t) addr,
626 (intptr_t) page_size) > 0);
627
628 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
629 static volatile address last_addr =
630 (address) os::non_memory_address_word();
631
632 // In conservative mode, don't unguard unless the address is in the VM
633 if (addr != last_addr &&
634 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
635
636 // Make memory rwx and retry
637 address page_start =
638 (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
639 bool res = os::protect_memory((char*) page_start, page_size,
640 os::MEM_PROT_RWX);
641
642 log_debug(os)("Execution protection violation "
643 "at " INTPTR_FORMAT
644 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", p2i(addr),
645 p2i(page_start), (res ? "success" : "failed"), errno);
646 stub = pc;
647
648 // Set last_addr so if we fault again at the same address, we don't end
649 // up in an endless loop.
650 //
651 // There are two potential complications here. Two threads trapping at
652 // the same address at the same time could cause one of the threads to
653 // think it already unguarded, and abort the VM. Likely very rare.
654 //
655 // The other race involves two threads alternately trapping at
656 // different addresses and failing to unguard the page, resulting in
657 // an endless loop. This condition is probably even more unlikely than
658 // the first.
659 //
660 // Although both cases could be avoided by using locks or thread local
661 // last_addr, these solutions are unnecessary complication: this
662 // handler is a best-effort safety net, not a complete solution. It is
663 // disabled by default and should only be used as a workaround in case
664 // we missed any no-execute-unsafe VM code.
665
666 last_addr = addr;
667 }
668 }
669 }
670
671 if (stub != NULL) {
672 // save all thread context in case we need to restore it
673
674 if (thread != NULL) thread->set_saved_exception_pc(pc);
675 // 12/02/99: On Sparc it appears that the full context is also saved
676 // but as yet, no one looks at or restores that saved context
677 os::Solaris::ucontext_set_pc(uc, stub);
678 return true;
679 }
680
681 // signal-chaining
682 if (os::Solaris::chained_handler(sig, info, ucVoid)) {
683 return true;
684 }
685
686 #ifndef AMD64
687 // Workaround (bug 4900493) for Solaris kernel bug 4966651.
688 // Handle an undefined selector caused by an attempt to assign
689 // fs in libthread getipriptr(). With the current libthread design every 512
690 // thread creations the LDT for a private thread data structure is extended
691 // and thre is a hazard that and another thread attempting a thread creation
692 // will use a stale LDTR that doesn't reflect the structure's growth,
693 // causing a GP fault.
694 // Enforce the probable limit of passes through here to guard against an
695 // infinite loop if some other move to fs caused the GP fault. Note that
696 // this loop counter is ultimately a heuristic as it is possible for
697 // more than one thread to generate this fault at a time in an MP system.
698 // In the case of the loop count being exceeded or if the poll fails
699 // just fall through to a fatal error.
700 // If there is some other source of T_GPFLT traps and the text at EIP is
701 // unreadable this code will loop infinitely until the stack is exausted.
702 // The key to diagnosis in this case is to look for the bottom signal handler
703 // frame.
704
705 if(! IgnoreLibthreadGPFault) {
706 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) {
707 const unsigned char *p =
708 (unsigned const char *) uc->uc_mcontext.gregs[EIP];
709
710 // Expected instruction?
711
712 if(p[0] == movlfs[0] && p[1] == movlfs[1]) {
713
714 Atomic::inc(&ldtr_refresh);
715
716 // Infinite loop?
717
718 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) {
719
720 // No, force scheduling to get a fresh view of the LDTR
721
722 if(poll(NULL, 0, 10) == 0) {
723
724 // Retry the move
725
726 return false;
727 }
728 }
729 }
730 }
731 }
732 #endif // !AMD64
733
734 if (!abort_if_unrecognized) {
735 // caller wants another chance, so give it to him
736 return false;
737 }
738
739 if (!os::Solaris::libjsig_is_loaded) {
740 struct sigaction oldAct;
741 sigaction(sig, (struct sigaction *)0, &oldAct);
742 if (oldAct.sa_sigaction != signalHandler) {
743 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
744 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
745 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand);
746 }
747 }
748
749 if (pc == NULL && uc != NULL) {
750 pc = (address) uc->uc_mcontext.gregs[REG_PC];
751 }
752
753 // unmask current signal
754 sigset_t newset;
755 sigemptyset(&newset);
756 sigaddset(&newset, sig);
757 sigprocmask(SIG_UNBLOCK, &newset, NULL);
758
759 // Determine which sort of error to throw. Out of swap may signal
760 // on the thread stack, which could get a mapping error when touched.
761 address addr = (address) info->si_addr;
762 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) {
763 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack.");
764 }
765
766 VMError::report_and_die(t, sig, pc, info, ucVoid);
767
768 ShouldNotReachHere();
769 return false;
770 }
771
772 void os::print_context(outputStream *st, const void *context) {
773 if (context == NULL) return;
774
775 const ucontext_t *uc = (const ucontext_t*)context;
776 st->print_cr("Registers:");
777 #ifdef AMD64
778 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
779 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
780 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
781 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
782 st->cr();
783 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
784 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
785 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
786 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
787 st->cr();
788 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
789 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
790 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
791 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
792 st->cr();
793 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
794 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
795 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
796 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
797 st->cr();
798 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
799 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]);
800 #else
801 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]);
802 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]);
803 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]);
804 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]);
805 st->cr();
806 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]);
807 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]);
808 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]);
809 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]);
810 st->cr();
811 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]);
812 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]);
813 #endif // AMD64
814 st->cr();
815 st->cr();
816
817 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
818 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
819 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
820 st->cr();
821
822 // Note: it may be unsafe to inspect memory near pc. For example, pc may
823 // point to garbage if entry point in an nmethod is corrupted. Leave
824 // this at the end, and hope for the best.
825 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
826 address pc = epc.pc();
827 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
828 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
829 }
830
831 void os::print_register_info(outputStream *st, const void *context) {
832 if (context == NULL) return;
833
834 const ucontext_t *uc = (const ucontext_t*)context;
835
836 st->print_cr("Register to memory mapping:");
837 st->cr();
838
839 // this is horrendously verbose but the layout of the registers in the
840 // context does not match how we defined our abstract Register set, so
841 // we can't just iterate through the gregs area
842
843 // this is only for the "general purpose" registers
844
845 #ifdef AMD64
846 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
847 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
848 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
849 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
850 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
851 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]);
852 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
853 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
854 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]);
855 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]);
856 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]);
857 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]);
858 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]);
859 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]);
860 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]);
861 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]);
862 #else
863 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]);
864 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]);
865 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]);
866 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]);
867 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]);
868 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]);
869 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]);
870 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]);
871 #endif
872
873 st->cr();
874 }
875
876
877 #ifdef AMD64
878 void os::Solaris::init_thread_fpu_state(void) {
879 // Nothing to do
880 }
881 #else
882 // From solaris_i486.s
883 extern "C" void fixcw();
884
885 void os::Solaris::init_thread_fpu_state(void) {
886 // Set fpu to 53 bit precision. This happens too early to use a stub.
887 fixcw();
888 }
889
890 // These routines are the initial value of atomic_xchg_entry(),
891 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry()
892 // until initialization is complete.
893 // TODO - replace with .il implementation when compiler supports it.
894
895 typedef jint xchg_func_t (jint, volatile jint*);
896 typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
897 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
898 typedef jint add_func_t (jint, volatile jint*);
899
900 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
901 // try to use the stub:
902 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
903
904 if (func != NULL) {
905 os::atomic_xchg_func = func;
906 return (*func)(exchange_value, dest);
907 }
908 assert(Threads::number_of_threads() == 0, "for bootstrap only");
909
910 jint old_value = *dest;
911 *dest = exchange_value;
912 return old_value;
913 }
914
915 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
916 // try to use the stub:
917 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
918
919 if (func != NULL) {
920 os::atomic_cmpxchg_func = func;
921 return (*func)(exchange_value, dest, compare_value);
922 }
923 assert(Threads::number_of_threads() == 0, "for bootstrap only");
924
925 jint old_value = *dest;
926 if (old_value == compare_value)
927 *dest = exchange_value;
928 return old_value;
929 }
930
931 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
932 // try to use the stub:
933 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
934
935 if (func != NULL) {
936 os::atomic_cmpxchg_long_func = func;
937 return (*func)(exchange_value, dest, compare_value);
938 }
939 assert(Threads::number_of_threads() == 0, "for bootstrap only");
940
941 jlong old_value = *dest;
942 if (old_value == compare_value)
943 *dest = exchange_value;
944 return old_value;
945 }
946
947 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
948 // try to use the stub:
949 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
950
951 if (func != NULL) {
952 os::atomic_add_func = func;
953 return (*func)(add_value, dest);
954 }
955 assert(Threads::number_of_threads() == 0, "for bootstrap only");
956
957 return (*dest) += add_value;
958 }
959
960 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
961 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
962 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
963 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
964
965 extern "C" void _solaris_raw_setup_fpu(address ptr);
966 void os::setup_fpu() {
967 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
968 _solaris_raw_setup_fpu(fpu_cntrl);
969 }
970 #endif // AMD64
971
972 #ifndef PRODUCT
973 void os::verify_stack_alignment() {
974 #ifdef AMD64
975 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
976 #endif
977 }
978 #endif
979
980 int os::extra_bang_size_in_bytes() {
981 // JDK-8050147 requires the full cache line bang for x86.
982 return VM_Version::L1_line_size();
983 }