1 /*
2 * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2017, 2020 SAP SE. All rights reserved.
4 * Copyright (c) 2023, Red Hat, Inc. and/or its affiliates.
5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 *
7 * This code is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 only, as
9 * published by the Free Software Foundation.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 *
25 */
26
27 #include "precompiled.hpp"
28 #include "jvm.h"
29 #include "cds/metaspaceShared.hpp"
30 #include "code/codeCache.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/disassembler.hpp"
33 #include "gc/shared/gcConfig.hpp"
34 #include "gc/shared/gcLogPrecious.hpp"
35 #include "logging/logConfiguration.hpp"
36 #include "memory/metaspace.hpp"
37 #include "memory/metaspaceUtils.hpp"
38 #include "memory/resourceArea.inline.hpp"
39 #include "memory/universe.hpp"
40 #include "oops/compressedOops.hpp"
41 #include "prims/whitebox.hpp"
42 #include "runtime/arguments.hpp"
43 #include "runtime/atomic.hpp"
44 #include "runtime/frame.inline.hpp"
45 #include "runtime/init.hpp"
46 #include "runtime/os.hpp"
47 #include "runtime/osThread.hpp"
48 #include "runtime/safefetch.hpp"
49 #include "runtime/safepointMechanism.hpp"
50 #include "runtime/stackFrameStream.inline.hpp"
51 #include "runtime/thread.inline.hpp"
52 #include "runtime/threadSMR.hpp"
53 #include "runtime/trimNativeHeap.hpp"
54 #include "runtime/vmThread.hpp"
55 #include "runtime/vmOperations.hpp"
56 #include "runtime/vm_version.hpp"
57 #include "runtime/flags/jvmFlag.hpp"
58 #include "services/memTracker.hpp"
59 #include "utilities/debug.hpp"
60 #include "utilities/decoder.hpp"
61 #include "utilities/defaultStream.hpp"
62 #include "utilities/events.hpp"
63 #include "utilities/vmError.hpp"
64 #include "utilities/macros.hpp"
65 #if INCLUDE_JFR
66 #include "jfr/jfr.hpp"
67 #endif
68
69 #ifndef PRODUCT
70 #include <signal.h>
71 #endif // PRODUCT
72
73 bool VMError::coredump_status;
74 char VMError::coredump_message[O_BUFLEN];
75 int VMError::_current_step;
76 const char* VMError::_current_step_info;
77 volatile jlong VMError::_reporting_start_time = -1;
78 volatile bool VMError::_reporting_did_timeout = false;
79 volatile jlong VMError::_step_start_time = -1;
80 volatile bool VMError::_step_did_timeout = false;
81 volatile intptr_t VMError::_first_error_tid = -1;
82 int VMError::_id;
83 const char* VMError::_message;
84 char VMError::_detail_msg[1024];
85 Thread* VMError::_thread;
86 address VMError::_pc;
87 void* VMError::_siginfo;
88 void* VMError::_context;
89 bool VMError::_print_native_stack_used = false;
90 const char* VMError::_filename;
91 int VMError::_lineno;
92 size_t VMError::_size;
93
94 // List of environment variables that should be reported in error log file.
95 static const char* env_list[] = {
96 // All platforms
97 "JAVA_HOME", "JAVA_TOOL_OPTIONS", "_JAVA_OPTIONS", "CLASSPATH",
98 "PATH", "USERNAME",
99
100 "XDG_CACHE_HOME", "XDG_CONFIG_HOME", "FC_LANG", "FONTCONFIG_USE_MMAP",
101
102 // Env variables that are defined on Linux/BSD
103 "LD_LIBRARY_PATH", "LD_PRELOAD", "SHELL", "DISPLAY",
104 "HOSTTYPE", "OSTYPE", "ARCH", "MACHTYPE",
105 "LANG", "LC_ALL", "LC_CTYPE", "LC_NUMERIC", "LC_TIME",
106 "TERM", "TMPDIR", "TZ",
107
108 // defined on AIX
109 "LIBPATH", "LDR_PRELOAD", "LDR_PRELOAD64",
110
111 // defined on Linux/AIX/BSD
112 "_JAVA_SR_SIGNUM",
113
114 // defined on Darwin
115 "DYLD_LIBRARY_PATH", "DYLD_FALLBACK_LIBRARY_PATH",
116 "DYLD_FRAMEWORK_PATH", "DYLD_FALLBACK_FRAMEWORK_PATH",
117 "DYLD_INSERT_LIBRARIES",
118
119 // defined on Windows
120 "OS", "PROCESSOR_IDENTIFIER", "_ALT_JAVA_HOME_DIR", "TMP", "TEMP",
121
122 (const char *)0
123 };
124
125 // A simple parser for -XX:OnError, usage:
126 // ptr = OnError;
127 // while ((cmd = next_OnError_command(buffer, sizeof(buffer), &ptr) != NULL)
128 // ... ...
129 static char* next_OnError_command(char* buf, int buflen, const char** ptr) {
130 if (ptr == NULL || *ptr == NULL) return NULL;
131
132 const char* cmd = *ptr;
133
134 // skip leading blanks or ';'
135 while (*cmd == ' ' || *cmd == ';') cmd++;
136
137 if (*cmd == '\0') return NULL;
138
139 const char * cmdend = cmd;
140 while (*cmdend != '\0' && *cmdend != ';') cmdend++;
141
142 Arguments::copy_expand_pid(cmd, cmdend - cmd, buf, buflen);
143
144 *ptr = (*cmdend == '\0' ? cmdend : cmdend + 1);
145 return buf;
146 }
147
148 static void print_bug_submit_message(outputStream *out, Thread *thread) {
149 if (out == NULL) return;
150 const char *url = Arguments::java_vendor_url_bug();
151 if (url == NULL || *url == '\0')
152 url = JDK_Version::runtime_vendor_vm_bug_url();
153 if (url != NULL && *url != '\0') {
154 out->print_raw_cr("# If you would like to submit a bug report, please visit:");
155 out->print_raw ("# ");
156 out->print_raw_cr(url);
157 }
158 // If the crash is in native code, encourage user to submit a bug to the
159 // provider of that code.
160 if (thread && thread->is_Java_thread() &&
161 !thread->is_hidden_from_external_view()) {
162 if (thread->as_Java_thread()->thread_state() == _thread_in_native) {
163 out->print_cr("# The crash happened outside the Java Virtual Machine in native code.\n# See problematic frame for where to report the bug.");
164 }
165 }
166 out->print_raw_cr("#");
167 }
168
169 void VMError::record_coredump_status(const char* message, bool status) {
170 coredump_status = status;
171 strncpy(coredump_message, message, sizeof(coredump_message));
172 coredump_message[sizeof(coredump_message)-1] = 0;
173 }
174
175 // Return a string to describe the error
176 char* VMError::error_string(char* buf, int buflen) {
177 char signame_buf[64];
178 const char *signame = os::exception_name(_id, signame_buf, sizeof(signame_buf));
179
180 if (signame) {
181 jio_snprintf(buf, buflen,
182 "%s (0x%x) at pc=" PTR_FORMAT ", pid=%d, tid=" UINTX_FORMAT,
183 signame, _id, _pc,
184 os::current_process_id(), os::current_thread_id());
185 } else if (_filename != NULL && _lineno > 0) {
186 // skip directory names
187 char separator = os::file_separator()[0];
188 const char *p = strrchr(_filename, separator);
189 int n = jio_snprintf(buf, buflen,
190 "Internal Error at %s:%d, pid=%d, tid=" UINTX_FORMAT,
191 p ? p + 1 : _filename, _lineno,
192 os::current_process_id(), os::current_thread_id());
193 if (n >= 0 && n < buflen && _message) {
194 if (strlen(_detail_msg) > 0) {
195 jio_snprintf(buf + n, buflen - n, "%s%s: %s",
196 os::line_separator(), _message, _detail_msg);
197 } else {
198 jio_snprintf(buf + n, buflen - n, "%sError: %s",
199 os::line_separator(), _message);
200 }
201 }
202 } else {
203 jio_snprintf(buf, buflen,
204 "Internal Error (0x%x), pid=%d, tid=" UINTX_FORMAT,
205 _id, os::current_process_id(), os::current_thread_id());
206 }
207
208 return buf;
209 }
210
211 void VMError::print_stack_trace(outputStream* st, JavaThread* jt,
212 char* buf, int buflen, bool verbose) {
213 #ifdef ZERO
214 if (jt->zero_stack()->sp() && jt->top_zero_frame()) {
215 // StackFrameStream uses the frame anchor, which may not have
216 // been set up. This can be done at any time in Zero, however,
217 // so if it hasn't been set up then we just set it up now and
218 // clear it again when we're done.
219 bool has_last_Java_frame = jt->has_last_Java_frame();
220 if (!has_last_Java_frame)
221 jt->set_last_Java_frame();
222 st->print("Java frames:");
223 st->cr();
224
225 // Print the frames
226 StackFrameStream sfs(jt, true /* update */, true /* process_frames */);
227 for(int i = 0; !sfs.is_done(); sfs.next(), i++) {
228 sfs.current()->zero_print_on_error(i, st, buf, buflen);
229 st->cr();
230 }
231
232 // Reset the frame anchor if necessary
233 if (!has_last_Java_frame)
234 jt->reset_last_Java_frame();
235 }
236 #else
237 if (jt->has_last_Java_frame()) {
238 st->print_cr("Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)");
239 for (StackFrameStream sfs(jt, true /* update */, true /* process_frames */); !sfs.is_done(); sfs.next()) {
240 sfs.current()->print_on_error(st, buf, buflen, verbose);
241 st->cr();
242 }
243 }
244 #endif // ZERO
245 }
246
247 /**
248 * Adds `value` to `list` iff it's not already present and there is sufficient
249 * capacity (i.e. length(list) < `list_capacity`). The length of the list
250 * is the index of the first nullptr entry or `list_capacity` if there are
251 * no nullptr entries.
252 *
253 * @ return true if the value was added, false otherwise
254 */
255 static bool add_if_absent(address value, address* list, int list_capacity) {
256 for (int i = 0; i < list_capacity; i++) {
257 if (list[i] == value) {
258 return false;
259 }
260 if (list[i] == nullptr) {
261 list[i] = value;
262 if (i + 1 < list_capacity) {
263 list[i + 1] = nullptr;
264 }
265 return true;
266 }
267 }
268 return false;
269 }
270
271 /**
272 * Prints the VM generated code unit, if any, containing `pc` if it has not already
273 * been printed. If the code unit is an InterpreterCodelet or StubCodeDesc, it is
274 * only printed if `is_crash_pc` is true.
275 *
276 * @param printed array of code units that have already been printed (delimited by NULL entry)
277 * @param printed_capacity the capacity of `printed`
278 * @return true if the code unit was printed, false otherwise
279 */
280 static bool print_code(outputStream* st, Thread* thread, address pc, bool is_crash_pc,
281 address* printed, int printed_capacity) {
282 if (Interpreter::contains(pc)) {
283 if (is_crash_pc) {
284 // The interpreter CodeBlob is very large so try to print the codelet instead.
285 InterpreterCodelet* codelet = Interpreter::codelet_containing(pc);
286 if (codelet != nullptr) {
287 if (add_if_absent((address) codelet, printed, printed_capacity)) {
288 codelet->print_on(st);
289 Disassembler::decode(codelet->code_begin(), codelet->code_end(), st);
290 return true;
291 }
292 }
293 }
294 } else {
295 StubCodeDesc* desc = StubCodeDesc::desc_for(pc);
296 if (desc != nullptr) {
297 if (is_crash_pc) {
298 if (add_if_absent((address) desc, printed, printed_capacity)) {
299 desc->print_on(st);
300 Disassembler::decode(desc->begin(), desc->end(), st);
301 return true;
302 }
303 }
304 } else if (thread != nullptr) {
305 CodeBlob* cb = CodeCache::find_blob(pc);
306 if (cb != nullptr && add_if_absent((address) cb, printed, printed_capacity)) {
307 // Disassembling nmethod will incur resource memory allocation,
308 // only do so when thread is valid.
309 ResourceMark rm(thread);
310 Disassembler::decode(cb, st);
311 st->cr();
312 return true;
313 }
314 }
315 }
316 return false;
317 }
318
319 // Like above, but only try to figure out a short name. Return nullptr if not found.
320 static const char* find_code_name(address pc) {
321 if (Interpreter::contains(pc)) {
322 InterpreterCodelet* codelet = Interpreter::codelet_containing(pc);
323 if (codelet != nullptr) {
324 return codelet->description();
325 }
326 } else {
327 StubCodeDesc* desc = StubCodeDesc::desc_for(pc);
328 if (desc != nullptr) {
329 return desc->name();
330 } else {
331 CodeBlob* cb = CodeCache::find_blob(pc);
332 if (cb != nullptr) {
333 return cb->name();
334 }
335 }
336 }
337 return nullptr;
338 }
339
340 /**
341 * Gets the caller frame of `fr`.
342 *
343 * @returns an invalid frame (i.e. fr.pc() === 0) if the caller cannot be obtained
344 */
345 static frame next_frame(frame fr, Thread* t) {
346 // Compiled code may use EBP register on x86 so it looks like
347 // non-walkable C frame. Use frame.sender() for java frames.
348 frame invalid;
349 if (t != nullptr && t->is_Java_thread()) {
350 // Catch very first native frame by using stack address.
351 // For JavaThread stack_base and stack_size should be set.
352 if (!t->is_in_full_stack((address)(fr.real_fp() + 1))) {
353 return invalid;
354 }
355 if (fr.is_java_frame() || fr.is_native_frame() || fr.is_runtime_frame()) {
356 RegisterMap map(t->as_Java_thread(), false); // No update
357 return fr.sender(&map);
358 } else {
359 // is_first_C_frame() does only simple checks for frame pointer,
360 // it will pass if java compiled code has a pointer in EBP.
361 if (os::is_first_C_frame(&fr)) return invalid;
362 return os::get_sender_for_C_frame(&fr);
363 }
364 } else {
365 if (os::is_first_C_frame(&fr)) return invalid;
366 return os::get_sender_for_C_frame(&fr);
367 }
368 }
369
370 void VMError::print_native_stack(outputStream* st, frame fr, Thread* t, char* buf, int buf_size) {
371
372 // see if it's a valid frame
373 if (fr.pc()) {
374 st->print_cr("Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)");
375
376 int count = 0;
377 while (count++ < StackPrintLimit) {
378 fr.print_on_error(st, buf, buf_size);
379 if (fr.pc()) { // print source file and line, if available
380 char buf[128];
381 int line_no;
382 if (Decoder::get_source_info(fr.pc(), buf, sizeof(buf), &line_no)) {
383 st->print(" (%s:%d)", buf, line_no);
384 }
385 }
386 st->cr();
387 fr = next_frame(fr, t);
388 if (fr.pc() == nullptr) {
389 break;
390 }
391 }
392
393 if (count > StackPrintLimit) {
394 st->print_cr("...<more frames>...");
395 }
396
397 st->cr();
398 }
399 }
400
401 static void print_oom_reasons(outputStream* st) {
402 st->print_cr("# Possible reasons:");
403 st->print_cr("# The system is out of physical RAM or swap space");
404 if (UseCompressedOops) {
405 st->print_cr("# This process is running with CompressedOops enabled, and the Java Heap may be blocking the growth of the native heap");
406 }
407 if (LogBytesPerWord == 2) {
408 st->print_cr("# In 32 bit mode, the process size limit was hit");
409 }
410 st->print_cr("# Possible solutions:");
411 st->print_cr("# Reduce memory load on the system");
412 st->print_cr("# Increase physical memory or swap space");
413 st->print_cr("# Check if swap backing store is full");
414 if (LogBytesPerWord == 2) {
415 st->print_cr("# Use 64 bit Java on a 64 bit OS");
416 }
417 st->print_cr("# Decrease Java heap size (-Xmx/-Xms)");
418 st->print_cr("# Decrease number of Java threads");
419 st->print_cr("# Decrease Java thread stack sizes (-Xss)");
420 st->print_cr("# Set larger code cache with -XX:ReservedCodeCacheSize=");
421 if (UseCompressedOops) {
422 switch (CompressedOops::mode()) {
423 case CompressedOops::UnscaledNarrowOop:
424 st->print_cr("# JVM is running with Unscaled Compressed Oops mode in which the Java heap is");
425 st->print_cr("# placed in the first 4GB address space. The Java Heap base address is the");
426 st->print_cr("# maximum limit for the native heap growth. Please use -XX:HeapBaseMinAddress");
427 st->print_cr("# to set the Java Heap base and to place the Java Heap above 4GB virtual address.");
428 break;
429 case CompressedOops::ZeroBasedNarrowOop:
430 st->print_cr("# JVM is running with Zero Based Compressed Oops mode in which the Java heap is");
431 st->print_cr("# placed in the first 32GB address space. The Java Heap base address is the");
432 st->print_cr("# maximum limit for the native heap growth. Please use -XX:HeapBaseMinAddress");
433 st->print_cr("# to set the Java Heap base and to place the Java Heap above 32GB virtual address.");
434 break;
435 default:
436 break;
437 }
438 }
439 st->print_cr("# This output file may be truncated or incomplete.");
440 }
441
442 static void report_vm_version(outputStream* st, char* buf, int buflen) {
443 // VM version
444 st->print_cr("#");
445 JDK_Version::current().to_string(buf, buflen);
446 const char* runtime_name = JDK_Version::runtime_name() != NULL ?
447 JDK_Version::runtime_name() : "";
448 const char* runtime_version = JDK_Version::runtime_version() != NULL ?
449 JDK_Version::runtime_version() : "";
450 const char* vendor_version = JDK_Version::runtime_vendor_version() != NULL ?
451 JDK_Version::runtime_vendor_version() : "";
452 const char* jdk_debug_level = VM_Version::printable_jdk_debug_level() != NULL ?
453 VM_Version::printable_jdk_debug_level() : "";
454
455 st->print_cr("# JRE version: %s%s%s (%s) (%sbuild %s)", runtime_name,
456 (*vendor_version != '\0') ? " " : "", vendor_version,
457 buf, jdk_debug_level, runtime_version);
458
459 // This is the long version with some default settings added
460 st->print_cr("# Java VM: %s%s%s (%s%s, %s%s%s%s%s%s, %s, %s)",
461 VM_Version::vm_name(),
462 (*vendor_version != '\0') ? " " : "", vendor_version,
463 jdk_debug_level,
464 VM_Version::vm_release(),
465 VM_Version::vm_info_string(),
466 TieredCompilation ? ", tiered" : "",
467 #if INCLUDE_JVMCI
468 EnableJVMCI ? ", jvmci" : "",
469 UseJVMCICompiler ? ", jvmci compiler" : "",
470 #else
471 "", "",
472 #endif
473 UseCompressedOops ? ", compressed oops" : "",
474 UseCompressedClassPointers ? ", compressed class ptrs" : "",
475 GCConfig::hs_err_name(),
476 VM_Version::vm_platform_string()
477 );
478 }
479
480 // Returns true if at least one thread reported a fatal error and fatal error handling is in process.
481 bool VMError::is_error_reported() {
482 return _first_error_tid != -1;
483 }
484
485 // Returns true if the current thread reported a fatal error.
486 bool VMError::is_error_reported_in_current_thread() {
487 return _first_error_tid == os::current_thread_id();
488 }
489
490 // Helper, return current timestamp for timeout handling.
491 jlong VMError::get_current_timestamp() {
492 return os::javaTimeNanos();
493 }
494 // Factor to translate the timestamp to seconds.
495 #define TIMESTAMP_TO_SECONDS_FACTOR (1000 * 1000 * 1000)
496
497 void VMError::record_reporting_start_time() {
498 const jlong now = get_current_timestamp();
499 Atomic::store(&_reporting_start_time, now);
500 }
501
502 jlong VMError::get_reporting_start_time() {
503 return Atomic::load(&_reporting_start_time);
504 }
505
506 void VMError::record_step_start_time() {
507 const jlong now = get_current_timestamp();
508 Atomic::store(&_step_start_time, now);
509 }
510
511 jlong VMError::get_step_start_time() {
512 return Atomic::load(&_step_start_time);
513 }
514
515 void VMError::clear_step_start_time() {
516 return Atomic::store(&_step_start_time, (jlong)0);
517 }
518
519 // This is the main function to report a fatal error. Only one thread can
520 // call this function, so we don't need to worry about MT-safety. But it's
521 // possible that the error handler itself may crash or die on an internal
522 // error, for example, when the stack/heap is badly damaged. We must be
523 // able to handle recursive errors that happen inside error handler.
524 //
525 // Error reporting is done in several steps. If a crash or internal error
526 // occurred when reporting an error, the nested signal/exception handler
527 // can skip steps that are already (or partially) done. Error reporting will
528 // continue from the next step. This allows us to retrieve and print
529 // information that may be unsafe to get after a fatal error. If it happens,
530 // you may find nested report_and_die() frames when you look at the stack
531 // in a debugger.
532 //
533 // In general, a hang in error handler is much worse than a crash or internal
534 // error, as it's harder to recover from a hang. Deadlock can happen if we
535 // try to grab a lock that is already owned by current thread, or if the
536 // owner is blocked forever (e.g. in os::infinite_sleep()). If possible, the
537 // error handler and all the functions it called should avoid grabbing any
538 // lock. An important thing to notice is that memory allocation needs a lock.
539 //
540 // We should avoid using large stack allocated buffers. Many errors happen
541 // when stack space is already low. Making things even worse is that there
542 // could be nested report_and_die() calls on stack (see above). Only one
543 // thread can report error, so large buffers are statically allocated in data
544 // segment.
545 void VMError::report(outputStream* st, bool _verbose) {
546
547 # define BEGIN if (_current_step == 0) { _current_step = __LINE__;
548 # define STEP(s) } if (_current_step < __LINE__) { _current_step = __LINE__; _current_step_info = s; \
549 record_step_start_time(); _step_did_timeout = false;
550 # define END clear_step_start_time(); }
551
552 // don't allocate large buffer on stack
553 static char buf[O_BUFLEN];
554
555 // Native stack trace may get stuck. We try to handle the last pc if it
556 // belongs to VM generated code.
557 address lastpc = nullptr;
558
559 BEGIN
560
561 STEP("printing fatal error message")
562
563 st->print_cr("#");
564 if (should_report_bug(_id)) {
565 st->print_cr("# A fatal error has been detected by the Java Runtime Environment:");
566 } else {
567 st->print_cr("# There is insufficient memory for the Java "
568 "Runtime Environment to continue.");
569 }
570
571 #ifdef ASSERT
572 // Error handler self tests
573
574 // test secondary error handling. Test it twice, to test that resetting
575 // error handler after a secondary crash works.
576 STEP("test secondary crash 1")
577 if (_verbose && TestCrashInErrorHandler != 0) {
578 st->print_cr("Will crash now (TestCrashInErrorHandler=" UINTX_FORMAT ")...",
579 TestCrashInErrorHandler);
580 controlled_crash(TestCrashInErrorHandler);
581 }
582
583 STEP("test secondary crash 2")
584 if (_verbose && TestCrashInErrorHandler != 0) {
585 st->print_cr("Will crash now (TestCrashInErrorHandler=" UINTX_FORMAT ")...",
586 TestCrashInErrorHandler);
587 controlled_crash(TestCrashInErrorHandler);
588 }
589
590 // TestUnresponsiveErrorHandler: We want to test both step timeouts and global timeout.
591 // Step to global timeout ratio is 4:1, so in order to be absolutely sure we hit the
592 // global timeout, let's execute the timeout step five times.
593 // See corresponding test in test/runtime/ErrorHandling/TimeoutInErrorHandlingTest.java
594 STEP("setup for test unresponsive error reporting step")
595 if (_verbose && TestUnresponsiveErrorHandler) {
596 // We record reporting_start_time for this test here because we
597 // care about the time spent executing TIMEOUT_TEST_STEP and not
598 // about the time it took us to get here.
599 tty->print_cr("Recording reporting_start_time for TestUnresponsiveErrorHandler.");
600 record_reporting_start_time();
601 }
602
603 #define TIMEOUT_TEST_STEP STEP("test unresponsive error reporting step") \
604 if (_verbose && TestUnresponsiveErrorHandler) { os::infinite_sleep(); }
605 TIMEOUT_TEST_STEP
606 TIMEOUT_TEST_STEP
607 TIMEOUT_TEST_STEP
608 TIMEOUT_TEST_STEP
609 TIMEOUT_TEST_STEP
610
611 STEP("test safefetch in error handler")
612 // test whether it is safe to use SafeFetch32 in Crash Handler. Test twice
613 // to test that resetting the signal handler works correctly.
614 if (_verbose && TestSafeFetchInErrorHandler) {
615 st->print_cr("Will test SafeFetch...");
616 int* const invalid_pointer = (int*)segfault_address;
617 const int x = 0x76543210;
618 int i1 = SafeFetch32(invalid_pointer, x);
619 int i2 = SafeFetch32(invalid_pointer, x);
620 if (i1 == x && i2 == x) {
621 st->print_cr("SafeFetch OK."); // Correctly deflected and returned default pattern
622 } else {
623 st->print_cr("??");
624 }
625 }
626 #endif // ASSERT
627
628 STEP("printing type of error")
629
630 switch(static_cast<unsigned int>(_id)) {
631 case OOM_MALLOC_ERROR:
632 case OOM_MMAP_ERROR:
633 case OOM_MPROTECT_ERROR:
634 if (_size) {
635 st->print("# Native memory allocation ");
636 st->print((_id == (int)OOM_MALLOC_ERROR) ? "(malloc) failed to allocate " :
637 (_id == (int)OOM_MMAP_ERROR) ? "(mmap) failed to map " :
638 "(mprotect) failed to protect ");
639 jio_snprintf(buf, sizeof(buf), SIZE_FORMAT, _size);
640 st->print("%s", buf);
641 st->print(" bytes.");
642 if (strlen(_detail_msg) > 0) {
643 st->print(" Error detail: ");
644 st->print("%s", _detail_msg);
645 }
646 st->cr();
647 } else {
648 if (strlen(_detail_msg) > 0) {
649 st->print("# ");
650 st->print_cr("%s", _detail_msg);
651 }
652 }
653 // In error file give some solutions
654 if (_verbose) {
655 print_oom_reasons(st);
656 } else {
657 return; // that's enough for the screen
658 }
659 break;
660 case INTERNAL_ERROR:
661 default:
662 break;
663 }
664
665 STEP("printing exception/signal name")
666
667 st->print_cr("#");
668 st->print("# ");
669 // Is it an OS exception/signal?
670 if (os::exception_name(_id, buf, sizeof(buf))) {
671 st->print("%s", buf);
672 st->print(" (0x%x)", _id); // signal number
673 st->print(" at pc=" PTR_FORMAT, p2i(_pc));
674 if (_siginfo != NULL && os::signal_sent_by_kill(_siginfo)) {
675 st->print(" (sent by kill)");
676 }
677 } else {
678 if (should_report_bug(_id)) {
679 st->print("Internal Error");
680 } else {
681 st->print("Out of Memory Error");
682 }
683 if (_filename != NULL && _lineno > 0) {
684 #ifdef PRODUCT
685 // In product mode chop off pathname?
686 char separator = os::file_separator()[0];
687 const char *p = strrchr(_filename, separator);
688 const char *file = p ? p+1 : _filename;
689 #else
690 const char *file = _filename;
691 #endif
692 st->print(" (%s:%d)", file, _lineno);
693 } else {
694 st->print(" (0x%x)", _id);
695 }
696 }
697
698 STEP("printing current thread and pid")
699
700 // process id, thread id
701 st->print(", pid=%d", os::current_process_id());
702 st->print(", tid=" UINTX_FORMAT, os::current_thread_id());
703 st->cr();
704
705 STEP("printing error message")
706
707 if (should_report_bug(_id)) { // already printed the message.
708 // error message
709 if (strlen(_detail_msg) > 0) {
710 st->print_cr("# %s: %s", _message ? _message : "Error", _detail_msg);
711 } else if (_message) {
712 st->print_cr("# Error: %s", _message);
713 }
714 }
715
716 STEP("printing Java version string")
717
718 report_vm_version(st, buf, sizeof(buf));
719
720 STEP("printing problematic frame")
721
722 // Print current frame if we have a context (i.e. it's a crash)
723 if (_context) {
724 st->print_cr("# Problematic frame:");
725 st->print("# ");
726 frame fr = os::fetch_frame_from_context(_context);
727 fr.print_on_error(st, buf, sizeof(buf));
728 st->cr();
729 st->print_cr("#");
730 }
731
732 STEP("printing core file information")
733 st->print("# ");
734 if (CreateCoredumpOnCrash) {
735 if (coredump_status) {
736 st->print("Core dump will be written. Default location: %s", coredump_message);
737 } else {
738 st->print("No core dump will be written. %s", coredump_message);
739 }
740 } else {
741 st->print("CreateCoredumpOnCrash turned off, no core file dumped");
742 }
743 st->cr();
744 st->print_cr("#");
745
746 JFR_ONLY(STEP("printing jfr information"))
747 JFR_ONLY(Jfr::on_vm_error_report(st);)
748
749 STEP("printing bug submit message")
750
751 if (should_submit_bug_report(_id) && _verbose) {
752 print_bug_submit_message(st, _thread);
753 }
754
755 STEP("printing summary")
756
757 if (_verbose) {
758 st->cr();
759 st->print_cr("--------------- S U M M A R Y ------------");
760 st->cr();
761 }
762
763 STEP("printing VM option summary")
764
765 if (_verbose) {
766 // VM options
767 Arguments::print_summary_on(st);
768 st->cr();
769 }
770
771 STEP("printing summary machine and OS info")
772
773 if (_verbose) {
774 os::print_summary_info(st, buf, sizeof(buf));
775 }
776
777 STEP("printing date and time")
778
779 if (_verbose) {
780 os::print_date_and_time(st, buf, sizeof(buf));
781 }
782
783 STEP("printing thread")
784
785 if (_verbose) {
786 st->cr();
787 st->print_cr("--------------- T H R E A D ---------------");
788 st->cr();
789 }
790
791 STEP("printing current thread")
792
793 // current thread
794 if (_verbose) {
795 if (_thread) {
796 st->print("Current thread (" PTR_FORMAT "): ", p2i(_thread));
797 _thread->print_on_error(st, buf, sizeof(buf));
798 st->cr();
799 } else {
800 st->print_cr("Current thread is native thread");
801 }
802 st->cr();
803 }
804
805 STEP("printing current compile task")
806
807 if (_verbose && _thread && _thread->is_Compiler_thread()) {
808 CompilerThread* t = (CompilerThread*)_thread;
809 if (t->task()) {
810 st->cr();
811 st->print_cr("Current CompileTask:");
812 t->task()->print_line_on_error(st, buf, sizeof(buf));
813 st->cr();
814 }
815 }
816
817 STEP("printing stack bounds")
818
819 if (_verbose) {
820 st->print("Stack: ");
821
822 address stack_top;
823 size_t stack_size;
824
825 if (_thread) {
826 stack_top = _thread->stack_base();
827 stack_size = _thread->stack_size();
828 } else {
829 stack_top = os::current_stack_base();
830 stack_size = os::current_stack_size();
831 }
832
833 address stack_bottom = stack_top - stack_size;
834 st->print("[" PTR_FORMAT "," PTR_FORMAT "]", p2i(stack_bottom), p2i(stack_top));
835
836 frame fr = _context ? os::fetch_frame_from_context(_context)
837 : os::current_frame();
838
839 if (fr.sp()) {
840 st->print(", sp=" PTR_FORMAT, p2i(fr.sp()));
841 size_t free_stack_size = pointer_delta(fr.sp(), stack_bottom, 1024);
842 st->print(", free space=" SIZE_FORMAT "k", free_stack_size);
843 }
844
845 st->cr();
846 }
847
848 STEP("printing native stack")
849
850 if (_verbose) {
851 if (os::platform_print_native_stack(st, _context, buf, sizeof(buf), lastpc)) {
852 // We have printed the native stack in platform-specific code
853 // Windows/x64 needs special handling.
854 // Stack walking may get stuck. Try to find the calling code.
855 if (lastpc != nullptr) {
856 const char* name = find_code_name(lastpc);
857 if (name != nullptr) {
858 st->print_cr("The last pc belongs to %s (printed below).", name);
859 }
860 }
861 } else {
862 frame fr = _context ? os::fetch_frame_from_context(_context)
863 : os::current_frame();
864
865 print_native_stack(st, fr, _thread, buf, sizeof(buf));
866 _print_native_stack_used = true;
867 }
868 }
869
870 STEP("printing Java stack")
871
872 if (_verbose && _thread && _thread->is_Java_thread()) {
873 print_stack_trace(st, _thread->as_Java_thread(), buf, sizeof(buf));
874 }
875
876 STEP("printing target Java thread stack")
877
878 // printing Java thread stack trace if it is involved in GC crash
879 if (_verbose && _thread && (_thread->is_Named_thread())) {
880 Thread* thread = ((NamedThread *)_thread)->processed_thread();
881 if (thread != NULL && thread->is_Java_thread()) {
882 JavaThread* jt = thread->as_Java_thread();
883 st->print_cr("JavaThread " PTR_FORMAT " (nid = %d) was being processed", p2i(jt), jt->osthread()->thread_id());
884 print_stack_trace(st, jt, buf, sizeof(buf), true);
885 }
886 }
887
888 STEP("printing siginfo")
889
890 // signal no, signal code, address that caused the fault
891 if (_verbose && _siginfo) {
892 st->cr();
893 os::print_siginfo(st, _siginfo);
894 st->cr();
895 }
896
897 STEP("CDS archive access warning")
898
899 // Print an explicit hint if we crashed on access to the CDS archive.
900 if (_verbose && _siginfo) {
901 check_failing_cds_access(st, _siginfo);
902 st->cr();
903 }
904
905 STEP("printing registers")
906
907 // printing registers
908 if (_verbose && _context) {
909 os::print_context(st, _context);
910 st->cr();
911 }
912
913 STEP("printing register info")
914
915 // decode register contents if possible
916 if (_verbose && _context && _thread && Universe::is_fully_initialized()) {
917 ResourceMark rm(_thread);
918 os::print_register_info(st, _context);
919 st->cr();
920 }
921
922 STEP("printing top of stack, instructions near pc")
923
924 // printing top of stack, instructions near pc
925 if (_verbose && _context) {
926 os::print_tos_pc(st, _context);
927 st->cr();
928 }
929
930 STEP("inspecting top of stack")
931
932 // decode stack contents if possible
933 if (_verbose && _context && _thread && Universe::is_fully_initialized()) {
934 frame fr = os::fetch_frame_from_context(_context);
935 const int slots = 8;
936 const intptr_t *start = fr.sp();
937 const intptr_t *end = start + slots;
938 if (is_aligned(start, sizeof(intptr_t)) && os::is_readable_range(start, end)) {
939 st->print_cr("Stack slot to memory mapping:");
940 for (int i = 0; i < slots; ++i) {
941 st->print("stack at sp + %d slots: ", i);
942 ResourceMark rm(_thread);
943 os::print_location(st, *(start + i));
944 }
945 }
946 st->cr();
947 }
948
949 STEP("printing code blobs if possible")
950
951 if (_verbose) {
952 const int printed_capacity = max_error_log_print_code;
953 address printed[printed_capacity];
954 printed[0] = nullptr;
955 int printed_len = 0;
956 // Even though ErrorLogPrintCodeLimit is ranged checked
957 // during argument parsing, there's no way to prevent it
958 // subsequently (i.e., after parsing) being set to a
959 // value outside the range.
960 int limit = MIN2(ErrorLogPrintCodeLimit, printed_capacity);
961 if (limit > 0) {
962 // Check if a pc was found by native stack trace above.
963 if (lastpc != nullptr) {
964 if (print_code(st, _thread, lastpc, true, printed, printed_capacity)) {
965 printed_len++;
966 }
967 }
968
969 // Scan the native stack
970 if (!_print_native_stack_used) {
971 // Only try to print code of the crashing frame since
972 // the native stack cannot be walked with next_frame.
973 if (print_code(st, _thread, _pc, true, printed, printed_capacity)) {
974 printed_len++;
975 }
976 } else {
977 frame fr = _context ? os::fetch_frame_from_context(_context)
978 : os::current_frame();
979 while (printed_len < limit && fr.pc() != nullptr) {
980 if (print_code(st, _thread, fr.pc(), fr.pc() == _pc, printed, printed_capacity)) {
981 printed_len++;
982 }
983 fr = next_frame(fr, _thread);
984 }
985 }
986
987 // Scan the Java stack
988 if (_thread != nullptr && _thread->is_Java_thread()) {
989 JavaThread* jt = _thread->as_Java_thread();
990 if (jt->has_last_Java_frame()) {
991 for (StackFrameStream sfs(jt, true /* update */, true /* process_frames */); printed_len < limit && !sfs.is_done(); sfs.next()) {
992 address pc = sfs.current()->pc();
993 if (print_code(st, _thread, pc, pc == _pc, printed, printed_capacity)) {
994 printed_len++;
995 }
996 }
997 }
998 }
999 }
1000 }
1001
1002 STEP("printing VM operation")
1003
1004 if (_verbose && _thread && _thread->is_VM_thread()) {
1005 VMThread* t = (VMThread*)_thread;
1006 VM_Operation* op = t->vm_operation();
1007 if (op) {
1008 op->print_on_error(st);
1009 st->cr();
1010 st->cr();
1011 }
1012 }
1013
1014 STEP("printing process")
1015
1016 if (_verbose) {
1017 st->cr();
1018 st->print_cr("--------------- P R O C E S S ---------------");
1019 st->cr();
1020 }
1021
1022 #ifndef _WIN32
1023 STEP("printing user info")
1024
1025 if (ExtensiveErrorReports && _verbose) {
1026 os::Posix::print_user_info(st);
1027 }
1028 #endif
1029
1030 STEP("printing all threads")
1031
1032 // all threads
1033 if (_verbose && _thread) {
1034 Threads::print_on_error(st, _thread, buf, sizeof(buf));
1035 st->cr();
1036 }
1037
1038 STEP("printing VM state")
1039
1040 if (_verbose) {
1041 // Safepoint state
1042 st->print("VM state: ");
1043
1044 if (SafepointSynchronize::is_synchronizing()) st->print("synchronizing");
1045 else if (SafepointSynchronize::is_at_safepoint()) st->print("at safepoint");
1046 else st->print("not at safepoint");
1047
1048 // Also see if error occurred during initialization or shutdown
1049 if (!Universe::is_fully_initialized()) {
1050 st->print(" (not fully initialized)");
1051 } else if (VM_Exit::vm_exited()) {
1052 st->print(" (shutting down)");
1053 } else {
1054 st->print(" (normal execution)");
1055 }
1056 st->cr();
1057 st->cr();
1058 }
1059
1060 STEP("printing owned locks on error")
1061
1062 // mutexes/monitors that currently have an owner
1063 if (_verbose) {
1064 print_owned_locks_on_error(st);
1065 st->cr();
1066 }
1067
1068 STEP("printing number of OutOfMemoryError and StackOverflow exceptions")
1069
1070 if (_verbose && Exceptions::has_exception_counts()) {
1071 st->print_cr("OutOfMemory and StackOverflow Exception counts:");
1072 Exceptions::print_exception_counts_on_error(st);
1073 st->cr();
1074 }
1075
1076 #ifdef _LP64
1077 STEP("printing compressed oops mode")
1078
1079 if (_verbose && UseCompressedOops) {
1080 CompressedOops::print_mode(st);
1081 st->cr();
1082 }
1083
1084 STEP("printing compressed klass pointers mode")
1085
1086 if (_verbose && UseCompressedClassPointers) {
1087 CDS_ONLY(MetaspaceShared::print_on(st);)
1088 Metaspace::print_compressed_class_space(st);
1089 CompressedKlassPointers::print_mode(st);
1090 st->cr();
1091 }
1092 #endif
1093
1094 STEP("printing heap information")
1095
1096 if (_verbose) {
1097 GCLogPrecious::print_on_error(st);
1098
1099 if (Universe::heap() != NULL) {
1100 Universe::heap()->print_on_error(st);
1101 st->cr();
1102 }
1103
1104 if (Universe::is_fully_initialized()) {
1105 st->print_cr("Polling page: " INTPTR_FORMAT, p2i(SafepointMechanism::get_polling_page()));
1106 st->cr();
1107 }
1108 }
1109
1110 STEP("printing metaspace information")
1111
1112 if (_verbose && Universe::is_fully_initialized()) {
1113 st->print_cr("Metaspace:");
1114 MetaspaceUtils::print_basic_report(st, 0);
1115 }
1116
1117 STEP("printing code cache information")
1118
1119 if (_verbose && Universe::is_fully_initialized()) {
1120 // print code cache information before vm abort
1121 CodeCache::print_summary(st);
1122 st->cr();
1123 }
1124
1125 STEP("printing ring buffers")
1126
1127 if (_verbose) {
1128 Events::print_all(st);
1129 st->cr();
1130 }
1131
1132 STEP("printing dynamic libraries")
1133
1134 if (_verbose) {
1135 // dynamic libraries, or memory map
1136 os::print_dll_info(st);
1137 st->cr();
1138 }
1139
1140 STEP("printing native decoder state")
1141
1142 if (_verbose) {
1143 Decoder::print_state_on(st);
1144 st->cr();
1145 }
1146
1147 STEP("printing VM options")
1148
1149 if (_verbose) {
1150 // VM options
1151 Arguments::print_on(st);
1152 st->cr();
1153 }
1154
1155 STEP("printing flags")
1156
1157 if (_verbose) {
1158 JVMFlag::printFlags(
1159 st,
1160 true, // with comments
1161 false, // no ranges
1162 true); // skip defaults
1163 st->cr();
1164 }
1165
1166 STEP("printing warning if internal testing API used")
1167
1168 if (WhiteBox::used()) {
1169 st->print_cr("Unsupported internal testing APIs have been used.");
1170 st->cr();
1171 }
1172
1173 STEP("printing log configuration")
1174 if (_verbose){
1175 st->print_cr("Logging:");
1176 LogConfiguration::describe_current_configuration(st);
1177 st->cr();
1178 }
1179
1180 STEP("printing all environment variables")
1181
1182 if (_verbose) {
1183 os::print_environment_variables(st, env_list);
1184 st->cr();
1185 }
1186
1187 #ifndef _WIN32
1188 STEP("printing locale settings")
1189
1190 if (_verbose) {
1191 os::Posix::print_active_locale(st);
1192 st->cr();
1193 }
1194 #endif
1195
1196 STEP("printing signal handlers")
1197
1198 if (_verbose) {
1199 os::print_signal_handlers(st, buf, sizeof(buf));
1200 st->cr();
1201 }
1202
1203 STEP("Native Memory Tracking")
1204 if (_verbose) {
1205 MemTracker::error_report(st);
1206 st->cr();
1207 }
1208
1209 STEP("printing periodic trim state")
1210
1211 if (_verbose) {
1212 NativeHeapTrimmer::print_state(st);
1213 st->cr();
1214 }
1215
1216 STEP("printing system")
1217
1218 if (_verbose) {
1219 st->cr();
1220 st->print_cr("--------------- S Y S T E M ---------------");
1221 st->cr();
1222 }
1223
1224 STEP("printing OS information")
1225
1226 if (_verbose) {
1227 os::print_os_info(st);
1228 st->cr();
1229 }
1230
1231 STEP("printing CPU info")
1232 if (_verbose) {
1233 os::print_cpu_info(st, buf, sizeof(buf));
1234 st->cr();
1235 }
1236
1237 STEP("printing memory info")
1238
1239 if (_verbose) {
1240 os::print_memory_info(st);
1241 st->cr();
1242 }
1243
1244 STEP("printing internal vm info")
1245
1246 if (_verbose) {
1247 st->print_cr("vm_info: %s", VM_Version::internal_vm_info_string());
1248 st->cr();
1249 }
1250
1251 // print a defined marker to show that error handling finished correctly.
1252 STEP("printing end marker")
1253
1254 if (_verbose) {
1255 st->print_cr("END.");
1256 }
1257
1258 END
1259
1260 # undef BEGIN
1261 # undef STEP
1262 # undef END
1263 }
1264
1265 // Report for the vm_info_cmd. This prints out the information above omitting
1266 // crash and thread specific information. If output is added above, it should be added
1267 // here also, if it is safe to call during a running process.
1268 void VMError::print_vm_info(outputStream* st) {
1269
1270 char buf[O_BUFLEN];
1271 report_vm_version(st, buf, sizeof(buf));
1272
1273 // STEP("printing summary")
1274
1275 st->cr();
1276 st->print_cr("--------------- S U M M A R Y ------------");
1277 st->cr();
1278
1279 // STEP("printing VM option summary")
1280
1281 // VM options
1282 Arguments::print_summary_on(st);
1283 st->cr();
1284
1285 // STEP("printing summary machine and OS info")
1286
1287 os::print_summary_info(st, buf, sizeof(buf));
1288
1289 // STEP("printing date and time")
1290
1291 os::print_date_and_time(st, buf, sizeof(buf));
1292
1293 // Skip: STEP("printing thread")
1294
1295 // STEP("printing process")
1296
1297 st->cr();
1298 st->print_cr("--------------- P R O C E S S ---------------");
1299 st->cr();
1300
1301 // STEP("printing number of OutOfMemoryError and StackOverflow exceptions")
1302
1303 if (Exceptions::has_exception_counts()) {
1304 st->print_cr("OutOfMemory and StackOverflow Exception counts:");
1305 Exceptions::print_exception_counts_on_error(st);
1306 st->cr();
1307 }
1308
1309 #ifdef _LP64
1310 // STEP("printing compressed oops mode")
1311 if (UseCompressedOops) {
1312 CompressedOops::print_mode(st);
1313 st->cr();
1314 }
1315
1316 // STEP("printing compressed class ptrs mode")
1317 if (UseCompressedClassPointers) {
1318 CDS_ONLY(MetaspaceShared::print_on(st);)
1319 Metaspace::print_compressed_class_space(st);
1320 CompressedKlassPointers::print_mode(st);
1321 st->cr();
1322 }
1323 #endif
1324
1325 // STEP("printing heap information")
1326
1327 if (Universe::is_fully_initialized()) {
1328 MutexLocker hl(Heap_lock);
1329 GCLogPrecious::print_on_error(st);
1330 Universe::heap()->print_on_error(st);
1331 st->cr();
1332 st->print_cr("Polling page: " INTPTR_FORMAT, p2i(SafepointMechanism::get_polling_page()));
1333 st->cr();
1334 }
1335
1336 // STEP("printing metaspace information")
1337
1338 if (Universe::is_fully_initialized()) {
1339 st->print_cr("Metaspace:");
1340 MetaspaceUtils::print_basic_report(st, 0);
1341 }
1342
1343 // STEP("printing code cache information")
1344
1345 if (Universe::is_fully_initialized()) {
1346 // print code cache information before vm abort
1347 CodeCache::print_summary(st);
1348 st->cr();
1349 }
1350
1351 // STEP("printing ring buffers")
1352
1353 Events::print_all(st);
1354 st->cr();
1355
1356 // STEP("printing dynamic libraries")
1357
1358 // dynamic libraries, or memory map
1359 os::print_dll_info(st);
1360 st->cr();
1361
1362 // STEP("printing VM options")
1363
1364 // VM options
1365 Arguments::print_on(st);
1366 st->cr();
1367
1368 // STEP("printing warning if internal testing API used")
1369
1370 if (WhiteBox::used()) {
1371 st->print_cr("Unsupported internal testing APIs have been used.");
1372 st->cr();
1373 }
1374
1375 // STEP("printing log configuration")
1376 st->print_cr("Logging:");
1377 LogConfiguration::describe(st);
1378 st->cr();
1379
1380 // STEP("printing all environment variables")
1381
1382 os::print_environment_variables(st, env_list);
1383 st->cr();
1384
1385 // STEP("printing locale settings")
1386 #ifndef _WIN32
1387 os::Posix::print_active_locale(st);
1388 st->cr();
1389 #endif
1390
1391 // STEP("printing signal handlers")
1392
1393 os::print_signal_handlers(st, buf, sizeof(buf));
1394 st->cr();
1395
1396 // STEP("Native Memory Tracking")
1397
1398 MemTracker::error_report(st);
1399 st->cr();
1400
1401 // STEP("printing periodic trim state")
1402 NativeHeapTrimmer::print_state(st);
1403 st->cr();
1404
1405
1406 // STEP("printing system")
1407 st->print_cr("--------------- S Y S T E M ---------------");
1408 st->cr();
1409
1410 // STEP("printing OS information")
1411
1412 os::print_os_info(st);
1413 st->cr();
1414
1415 // STEP("printing CPU info")
1416
1417 os::print_cpu_info(st, buf, sizeof(buf));
1418 st->cr();
1419
1420 // STEP("printing memory info")
1421
1422 os::print_memory_info(st);
1423 st->cr();
1424
1425 // STEP("printing internal vm info")
1426
1427 st->print_cr("vm_info: %s", VM_Version::internal_vm_info_string());
1428 st->cr();
1429
1430 // print a defined marker to show that error handling finished correctly.
1431 // STEP("printing end marker")
1432
1433 st->print_cr("END.");
1434 }
1435
1436 /** Expand a pattern into a buffer starting at pos and open a file using constructed path */
1437 static int expand_and_open(const char* pattern, bool overwrite_existing, char* buf, size_t buflen, size_t pos) {
1438 int fd = -1;
1439 int mode = O_RDWR | O_CREAT;
1440 if (overwrite_existing) {
1441 mode |= O_TRUNC;
1442 } else {
1443 mode |= O_EXCL;
1444 }
1445 if (Arguments::copy_expand_pid(pattern, strlen(pattern), &buf[pos], buflen - pos)) {
1446 fd = open(buf, mode, 0666);
1447 }
1448 return fd;
1449 }
1450
1451 /**
1452 * Construct file name for a log file and return it's file descriptor.
1453 * Name and location depends on pattern, default_pattern params and access
1454 * permissions.
1455 */
1456 static int prepare_log_file(const char* pattern, const char* default_pattern, bool overwrite_existing, char* buf, size_t buflen) {
1457 int fd = -1;
1458
1459 // If possible, use specified pattern to construct log file name
1460 if (pattern != NULL) {
1461 fd = expand_and_open(pattern, overwrite_existing, buf, buflen, 0);
1462 }
1463
1464 // Either user didn't specify, or the user's location failed,
1465 // so use the default name in the current directory
1466 if (fd == -1) {
1467 const char* cwd = os::get_current_directory(buf, buflen);
1468 if (cwd != NULL) {
1469 size_t pos = strlen(cwd);
1470 int fsep_len = jio_snprintf(&buf[pos], buflen-pos, "%s", os::file_separator());
1471 pos += fsep_len;
1472 if (fsep_len > 0) {
1473 fd = expand_and_open(default_pattern, overwrite_existing, buf, buflen, pos);
1474 }
1475 }
1476 }
1477
1478 // try temp directory if it exists.
1479 if (fd == -1) {
1480 const char* tmpdir = os::get_temp_directory();
1481 if (tmpdir != NULL && strlen(tmpdir) > 0) {
1482 int pos = jio_snprintf(buf, buflen, "%s%s", tmpdir, os::file_separator());
1483 if (pos > 0) {
1484 fd = expand_and_open(default_pattern, overwrite_existing, buf, buflen, pos);
1485 }
1486 }
1487 }
1488
1489 return fd;
1490 }
1491
1492 void VMError::report_and_die(Thread* thread, unsigned int sig, address pc, void* siginfo,
1493 void* context, const char* detail_fmt, ...)
1494 {
1495 va_list detail_args;
1496 va_start(detail_args, detail_fmt);
1497 report_and_die(sig, NULL, detail_fmt, detail_args, thread, pc, siginfo, context, NULL, 0, 0);
1498 va_end(detail_args);
1499 }
1500
1501 void VMError::report_and_die(Thread* thread, unsigned int sig, address pc, void* siginfo, void* context)
1502 {
1503 report_and_die(thread, sig, pc, siginfo, context, "%s", "");
1504 }
1505
1506 void VMError::report_and_die(Thread* thread, void* context, const char* filename, int lineno, const char* message,
1507 const char* detail_fmt, va_list detail_args)
1508 {
1509 report_and_die(INTERNAL_ERROR, message, detail_fmt, detail_args, thread, NULL, NULL, context, filename, lineno, 0);
1510 }
1511
1512 void VMError::report_and_die(Thread* thread, const char* filename, int lineno, size_t size,
1513 VMErrorType vm_err_type, const char* detail_fmt, va_list detail_args) {
1514 report_and_die(vm_err_type, NULL, detail_fmt, detail_args, thread, NULL, NULL, NULL, filename, lineno, size);
1515 }
1516
1517 void VMError::report_and_die(int id, const char* message, const char* detail_fmt, va_list detail_args,
1518 Thread* thread, address pc, void* siginfo, void* context, const char* filename,
1519 int lineno, size_t size)
1520 {
1521 // A single scratch buffer to be used from here on.
1522 // Do not rely on it being preserved across function calls.
1523 static char buffer[O_BUFLEN];
1524
1525 // File descriptor to tty to print an error summary to.
1526 // Hard wired to stdout; see JDK-8215004 (compatibility concerns).
1527 static const int fd_out = 1; // stdout
1528
1529 // File descriptor to the error log file.
1530 static int fd_log = -1;
1531
1532 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT
1533 // Disarm assertion poison page, since from this point on we do not need this mechanism anymore and it may
1534 // cause problems in error handling during native OOM, see JDK-8227275.
1535 disarm_assert_poison();
1536 #endif
1537
1538 // Use local fdStream objects only. Do not use global instances whose initialization
1539 // relies on dynamic initialization (see JDK-8214975). Do not rely on these instances
1540 // to carry over into recursions or invocations from other threads.
1541 fdStream out(fd_out);
1542 out.set_scratch_buffer(buffer, sizeof(buffer));
1543
1544 // Depending on the re-entrance depth at this point, fd_log may be -1 or point to an open hs-err file.
1545 fdStream log(fd_log);
1546 log.set_scratch_buffer(buffer, sizeof(buffer));
1547
1548 // How many errors occurred in error handler when reporting first_error.
1549 static int recursive_error_count;
1550
1551 // We will first print a brief message to standard out (verbose = false),
1552 // then save detailed information in log file (verbose = true).
1553 static bool out_done = false; // done printing to standard out
1554 static bool log_done = false; // done saving error log
1555
1556 intptr_t mytid = os::current_thread_id();
1557 if (_first_error_tid == -1 &&
1558 Atomic::cmpxchg(&_first_error_tid, (intptr_t)-1, mytid) == -1) {
1559
1560 if (SuppressFatalErrorMessage) {
1561 os::abort(CreateCoredumpOnCrash);
1562 }
1563
1564 // Initialize time stamps to use the same base.
1565 out.time_stamp().update_to(1);
1566 log.time_stamp().update_to(1);
1567
1568 _id = id;
1569 _message = message;
1570 _thread = thread;
1571 _pc = pc;
1572 _siginfo = siginfo;
1573 _context = context;
1574 _filename = filename;
1575 _lineno = lineno;
1576 _size = size;
1577 jio_vsnprintf(_detail_msg, sizeof(_detail_msg), detail_fmt, detail_args);
1578
1579 reporting_started();
1580 if (!TestUnresponsiveErrorHandler) {
1581 // Record reporting_start_time unless we're running the
1582 // TestUnresponsiveErrorHandler test. For that test we record
1583 // reporting_start_time at the beginning of the test.
1584 record_reporting_start_time();
1585 } else {
1586 out.print_raw_cr("Delaying recording reporting_start_time for TestUnresponsiveErrorHandler.");
1587 }
1588
1589 if (ShowMessageBoxOnError || PauseAtExit) {
1590 show_message_box(buffer, sizeof(buffer));
1591
1592 // User has asked JVM to abort. Reset ShowMessageBoxOnError so the
1593 // WatcherThread can kill JVM if the error handler hangs.
1594 ShowMessageBoxOnError = false;
1595 }
1596
1597 os::check_dump_limit(buffer, sizeof(buffer));
1598
1599 // reset signal handlers or exception filter; make sure recursive crashes
1600 // are handled properly.
1601 install_secondary_signal_handler();
1602 } else {
1603 #if defined(_WINDOWS)
1604 // If UseOSErrorReporting we call this for each level of the call stack
1605 // while searching for the exception handler. Only the first level needs
1606 // to be reported.
1607 if (UseOSErrorReporting && log_done) return;
1608 #endif
1609
1610 // This is not the first error, see if it happened in a different thread
1611 // or in the same thread during error reporting.
1612 if (_first_error_tid != mytid) {
1613 if (!SuppressFatalErrorMessage) {
1614 char msgbuf[64];
1615 jio_snprintf(msgbuf, sizeof(msgbuf),
1616 "[thread " INTX_FORMAT " also had an error]",
1617 mytid);
1618 out.print_raw_cr(msgbuf);
1619 }
1620
1621 // Error reporting is not MT-safe, nor can we let the current thread
1622 // proceed, so we block it.
1623 os::infinite_sleep();
1624
1625 } else {
1626 if (recursive_error_count++ > 30) {
1627 if (!SuppressFatalErrorMessage) {
1628 out.print_raw_cr("[Too many errors, abort]");
1629 }
1630 os::die();
1631 }
1632
1633 if (SuppressFatalErrorMessage) {
1634 // If we already hit a secondary error during abort, then calling
1635 // it again is likely to hit another one. But eventually, if we
1636 // don't deadlock somewhere, we will call os::die() above.
1637 os::abort(CreateCoredumpOnCrash);
1638 }
1639
1640 outputStream* const st = log.is_open() ? &log : &out;
1641 st->cr();
1642
1643 // Timeout handling.
1644 if (_step_did_timeout) {
1645 // The current step had a timeout. Lets continue reporting with the next step.
1646 st->print_raw("[timeout occurred during error reporting in step \"");
1647 st->print_raw(_current_step_info);
1648 st->print_cr("\"] after " INT64_FORMAT " s.",
1649 (int64_t)
1650 ((get_current_timestamp() - _step_start_time) / TIMESTAMP_TO_SECONDS_FACTOR));
1651 } else if (_reporting_did_timeout) {
1652 // We hit ErrorLogTimeout. Reporting will stop altogether. Let's wrap things
1653 // up, the process is about to be stopped by the WatcherThread.
1654 st->print_cr("------ Timeout during error reporting after " INT64_FORMAT " s. ------",
1655 (int64_t)
1656 ((get_current_timestamp() - _reporting_start_time) / TIMESTAMP_TO_SECONDS_FACTOR));
1657 st->flush();
1658 // Watcherthread is about to call os::die. Lets just wait.
1659 os::infinite_sleep();
1660 } else {
1661 // Crash or assert during error reporting. Lets continue reporting with the next step.
1662 stringStream ss(buffer, sizeof(buffer));
1663 // Note: this string does get parsed by a number of jtreg tests,
1664 // see hotspot/jtreg/runtime/ErrorHandling.
1665 ss.print("[error occurred during error reporting (%s), id 0x%x",
1666 _current_step_info, id);
1667 char signal_name[64];
1668 if (os::exception_name(id, signal_name, sizeof(signal_name))) {
1669 ss.print(", %s (0x%x) at pc=" PTR_FORMAT, signal_name, id, p2i(pc));
1670 } else {
1671 if (should_report_bug(id)) {
1672 ss.print(", Internal Error (%s:%d)",
1673 filename == NULL ? "??" : filename, lineno);
1674 } else {
1675 ss.print(", Out of Memory Error (%s:%d)",
1676 filename == NULL ? "??" : filename, lineno);
1677 }
1678 }
1679 ss.print("]");
1680 st->print_raw_cr(buffer);
1681 st->cr();
1682 }
1683 }
1684 }
1685
1686 // Part 1: print an abbreviated version (the '#' section) to stdout.
1687 if (!out_done) {
1688 // Suppress this output if we plan to print Part 2 to stdout too.
1689 // No need to have the "#" section twice.
1690 if (!(ErrorFileToStdout && out.fd() == 1)) {
1691 report(&out, false);
1692 }
1693
1694 out_done = true;
1695
1696 _current_step = 0;
1697 _current_step_info = "";
1698 }
1699
1700 // Part 2: print a full error log file (optionally to stdout or stderr).
1701 // print to error log file
1702 if (!log_done) {
1703 // see if log file is already open
1704 if (!log.is_open()) {
1705 // open log file
1706 if (ErrorFileToStdout) {
1707 fd_log = 1;
1708 } else if (ErrorFileToStderr) {
1709 fd_log = 2;
1710 } else {
1711 fd_log = prepare_log_file(ErrorFile, "hs_err_pid%p.log", true,
1712 buffer, sizeof(buffer));
1713 if (fd_log != -1) {
1714 out.print_raw("# An error report file with more information is saved as:\n# ");
1715 out.print_raw_cr(buffer);
1716 } else {
1717 out.print_raw_cr("# Can not save log file, dump to screen..");
1718 fd_log = 1;
1719 }
1720 }
1721 log.set_fd(fd_log);
1722 }
1723
1724 report(&log, true);
1725 log_done = true;
1726 _current_step = 0;
1727 _current_step_info = "";
1728
1729 if (fd_log > 3) {
1730 close(fd_log);
1731 fd_log = -1;
1732 }
1733
1734 log.set_fd(-1);
1735 }
1736
1737 JFR_ONLY(Jfr::on_vm_shutdown(true);)
1738
1739 if (PrintNMTStatistics) {
1740 fdStream fds(fd_out);
1741 MemTracker::final_report(&fds);
1742 }
1743
1744 static bool skip_replay = ReplayCompiles; // Do not overwrite file during replay
1745 if (DumpReplayDataOnError && _thread && _thread->is_Compiler_thread() && !skip_replay) {
1746 skip_replay = true;
1747 ciEnv* env = ciEnv::current();
1748 if (env != NULL) {
1749 const bool overwrite = false; // We do not overwrite an existing replay file.
1750 int fd = prepare_log_file(ReplayDataFile, "replay_pid%p.log", overwrite, buffer, sizeof(buffer));
1751 if (fd != -1) {
1752 FILE* replay_data_file = os::open(fd, "w");
1753 if (replay_data_file != NULL) {
1754 fileStream replay_data_stream(replay_data_file, /*need_close=*/true);
1755 env->dump_replay_data_unsafe(&replay_data_stream);
1756 out.print_raw("#\n# Compiler replay data is saved as:\n# ");
1757 out.print_raw_cr(buffer);
1758 } else {
1759 int e = errno;
1760 out.print_raw("#\n# Can't open file to dump replay data. Error: ");
1761 out.print_raw_cr(os::strerror(e));
1762 close(fd);
1763 }
1764 }
1765 }
1766 }
1767
1768 static bool skip_bug_url = !should_submit_bug_report(_id);
1769 if (!skip_bug_url) {
1770 skip_bug_url = true;
1771
1772 out.print_raw_cr("#");
1773 print_bug_submit_message(&out, _thread);
1774 }
1775
1776 static bool skip_OnError = false;
1777 if (!skip_OnError && OnError && OnError[0]) {
1778 skip_OnError = true;
1779
1780 // Flush output and finish logs before running OnError commands.
1781 ostream_abort();
1782
1783 out.print_raw_cr("#");
1784 out.print_raw ("# -XX:OnError=\"");
1785 out.print_raw (OnError);
1786 out.print_raw_cr("\"");
1787
1788 char* cmd;
1789 const char* ptr = OnError;
1790 while ((cmd = next_OnError_command(buffer, sizeof(buffer), &ptr)) != NULL){
1791 out.print_raw ("# Executing ");
1792 #if defined(LINUX) || defined(_ALLBSD_SOURCE)
1793 out.print_raw ("/bin/sh -c ");
1794 #elif defined(_WINDOWS)
1795 out.print_raw ("cmd /C ");
1796 #endif
1797 out.print_raw ("\"");
1798 out.print_raw (cmd);
1799 out.print_raw_cr("\" ...");
1800
1801 if (os::fork_and_exec(cmd) < 0) {
1802 out.print_cr("os::fork_and_exec failed: %s (%s=%d)",
1803 os::strerror(errno), os::errno_name(errno), errno);
1804 }
1805 }
1806
1807 // done with OnError
1808 OnError = NULL;
1809 }
1810
1811 if (WINDOWS_ONLY(!UseOSErrorReporting) NOT_WINDOWS(true)) {
1812 // os::abort() will call abort hooks, try it first.
1813 static bool skip_os_abort = false;
1814 if (!skip_os_abort) {
1815 skip_os_abort = true;
1816 bool dump_core = should_report_bug(_id);
1817 os::abort(dump_core && CreateCoredumpOnCrash, _siginfo, _context);
1818 }
1819
1820 // if os::abort() doesn't abort, try os::die();
1821 os::die();
1822 }
1823 }
1824
1825 /*
1826 * OnOutOfMemoryError scripts/commands executed while VM is a safepoint - this
1827 * ensures utilities such as jmap can observe the process is a consistent state.
1828 */
1829 class VM_ReportJavaOutOfMemory : public VM_Operation {
1830 private:
1831 const char* _message;
1832 public:
1833 VM_ReportJavaOutOfMemory(const char* message) { _message = message; }
1834 VMOp_Type type() const { return VMOp_ReportJavaOutOfMemory; }
1835 void doit();
1836 };
1837
1838 void VM_ReportJavaOutOfMemory::doit() {
1839 // Don't allocate large buffer on stack
1840 static char buffer[O_BUFLEN];
1841
1842 tty->print_cr("#");
1843 tty->print_cr("# java.lang.OutOfMemoryError: %s", _message);
1844 tty->print_cr("# -XX:OnOutOfMemoryError=\"%s\"", OnOutOfMemoryError);
1845
1846 // make heap parsability
1847 Universe::heap()->ensure_parsability(false); // no need to retire TLABs
1848
1849 char* cmd;
1850 const char* ptr = OnOutOfMemoryError;
1851 while ((cmd = next_OnError_command(buffer, sizeof(buffer), &ptr)) != NULL){
1852 tty->print("# Executing ");
1853 #if defined(LINUX)
1854 tty->print ("/bin/sh -c ");
1855 #endif
1856 tty->print_cr("\"%s\"...", cmd);
1857
1858 if (os::fork_and_exec(cmd, true) < 0) {
1859 tty->print_cr("os::fork_and_exec failed: %s (%s=%d)",
1860 os::strerror(errno), os::errno_name(errno), errno);
1861 }
1862 }
1863 }
1864
1865 void VMError::report_java_out_of_memory(const char* message) {
1866 if (OnOutOfMemoryError && OnOutOfMemoryError[0]) {
1867 MutexLocker ml(Heap_lock);
1868 VM_ReportJavaOutOfMemory op(message);
1869 VMThread::execute(&op);
1870 }
1871 }
1872
1873 void VMError::show_message_box(char *buf, int buflen) {
1874 bool yes;
1875 do {
1876 error_string(buf, buflen);
1877 yes = os::start_debugging(buf,buflen);
1878 } while (yes);
1879 }
1880
1881 // Fatal error handling is subject to several timeouts:
1882 // - a global timeout (controlled via ErrorLogTimeout)
1883 // - local error reporting step timeouts.
1884 //
1885 // The latter aims to "give the JVM a kick" if it gets stuck in one particular place during
1886 // error reporting. This prevents one error reporting step from hogging all the time allotted
1887 // to error reporting under ErrorLogTimeout.
1888 //
1889 // VMError::check_timeout() is called from the watcher thread and checks for either global
1890 // or step timeout. If a timeout happened, we interrupt the reporting thread and set either
1891 // _reporting_did_timeout or _step_did_timeout to signal which timeout fired. Function returns
1892 // true if the *global* timeout fired, which will cause WatcherThread to shut down the JVM
1893 // immediately.
1894 bool VMError::check_timeout() {
1895
1896 // This function is supposed to be called from watcher thread during fatal error handling only.
1897 assert(VMError::is_error_reported(), "Only call during error handling");
1898 assert(Thread::current()->is_Watcher_thread(), "Only call from watcher thread");
1899
1900 if (ErrorLogTimeout == 0) {
1901 return false;
1902 }
1903
1904 // There are three situations where we suppress the *global* error timeout:
1905 // - if the JVM is embedded and the launcher has its abort hook installed.
1906 // That must be allowed to run.
1907 // - if the user specified one or more OnError commands to run, and these
1908 // did not yet run. These must have finished.
1909 // - if the user (typically developer) specified ShowMessageBoxOnError,
1910 // and the error box has not yet been shown
1911 const bool ignore_global_timeout =
1912 (ShowMessageBoxOnError
1913 || (OnError != nullptr && OnError[0] != '\0')
1914 || Arguments::abort_hook() != nullptr);
1915
1916 const jlong now = get_current_timestamp();
1917
1918 // Global timeout hit?
1919 if (!ignore_global_timeout) {
1920 const jlong reporting_start_time = get_reporting_start_time();
1921 // Timestamp is stored in nanos.
1922 if (reporting_start_time > 0) {
1923 const jlong end = reporting_start_time + (jlong)ErrorLogTimeout * TIMESTAMP_TO_SECONDS_FACTOR;
1924 if (end <= now && !_reporting_did_timeout) {
1925 // We hit ErrorLogTimeout and we haven't interrupted the reporting
1926 // thread yet.
1927 _reporting_did_timeout = true;
1928 interrupt_reporting_thread();
1929 return true; // global timeout
1930 }
1931 }
1932 }
1933
1934 // Reporting step timeout?
1935 const jlong step_start_time = get_step_start_time();
1936 if (step_start_time > 0) {
1937 // A step times out after a quarter of the total timeout. Steps are mostly fast unless they
1938 // hang for some reason, so this simple rule allows for three hanging step and still
1939 // hopefully leaves time enough for the rest of the steps to finish.
1940 const int max_step_timeout_secs = 5;
1941 const jlong timeout_duration = MAX2((jlong)max_step_timeout_secs, (jlong)ErrorLogTimeout * TIMESTAMP_TO_SECONDS_FACTOR / 4);
1942 const jlong end = step_start_time + timeout_duration;
1943 if (end <= now && !_step_did_timeout) {
1944 // The step timed out and we haven't interrupted the reporting
1945 // thread yet.
1946 _step_did_timeout = true;
1947 interrupt_reporting_thread();
1948 return false; // (Not a global timeout)
1949 }
1950 }
1951
1952 return false;
1953
1954 }
1955
1956 #ifdef ASSERT
1957 typedef void (*voidfun_t)();
1958
1959 // Crash with an authentic sigfpe
1960 volatile int sigfpe_int = 0;
1961 static void crash_with_sigfpe() {
1962
1963 // generate a native synchronous SIGFPE where possible;
1964 sigfpe_int = sigfpe_int/sigfpe_int;
1965
1966 // if that did not cause a signal (e.g. on ppc), just
1967 // raise the signal.
1968 #ifndef _WIN32
1969 // OSX implements raise(sig) incorrectly so we need to
1970 // explicitly target the current thread
1971 pthread_kill(pthread_self(), SIGFPE);
1972 #endif
1973
1974 } // end: crash_with_sigfpe
1975
1976 // crash with sigsegv at non-null address.
1977 static void crash_with_segfault() {
1978
1979 int* crash_addr = reinterpret_cast<int*>(VMError::segfault_address);
1980 *crash_addr = 1;
1981
1982 } // end: crash_with_segfault
1983
1984 // crash in a controlled way:
1985 // 1 - assert
1986 // 2 - guarantee
1987 // 14 - SIGSEGV
1988 // 15 - SIGFPE
1989 void VMError::controlled_crash(int how) {
1990
1991 // Case 14 is tested by test/hotspot/jtreg/runtime/ErrorHandling/SafeFetchInErrorHandlingTest.java.
1992 // Case 15 is tested by test/hotspot/jtreg/runtime/ErrorHandling/SecondaryErrorTest.java.
1993 // Case 16 is tested by test/hotspot/jtreg/runtime/ErrorHandling/ThreadsListHandleInErrorHandlingTest.java.
1994 // Case 17 is tested by test/hotspot/jtreg/runtime/ErrorHandling/NestedThreadsListHandleInErrorHandlingTest.java.
1995
1996 // We try to grab Threads_lock to keep ThreadsSMRSupport::print_info_on()
1997 // from racing with Threads::add() or Threads::remove() as we
1998 // generate the hs_err_pid file. This makes our ErrorHandling tests
1999 // more stable.
2000 if (!Threads_lock->owned_by_self()) {
2001 Threads_lock->try_lock();
2002 // The VM is going to die so no need to unlock Thread_lock.
2003 }
2004
2005 switch (how) {
2006 case 1: assert(how == 0, "test assert"); break;
2007 case 2: guarantee(how == 0, "test guarantee"); break;
2008
2009 // The other cases are unused.
2010 case 14: crash_with_segfault(); break;
2011 case 15: crash_with_sigfpe(); break;
2012 case 16: {
2013 ThreadsListHandle tlh;
2014 fatal("Force crash with an active ThreadsListHandle.");
2015 }
2016 case 17: {
2017 ThreadsListHandle tlh;
2018 {
2019 ThreadsListHandle tlh2;
2020 fatal("Force crash with a nested ThreadsListHandle.");
2021 }
2022 }
2023 default:
2024 // If another number is given, give a generic crash.
2025 fatal("Crashing with number %d", how);
2026 }
2027 tty->print_cr("controlled_crash: survived intentional crash. Did you suppress the assert?");
2028 ShouldNotReachHere();
2029 }
2030 #endif // !ASSERT