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8276126: Dump time class transformation causes heap objects of non-bo…
…ot classes to be archived

Reviewed-by: iklam, minqi
  • Loading branch information
calvinccheung committed Dec 2, 2021
1 parent 7696897 commit d2b16c89855d584a563caa4f725802dc91a83407
Showing 11 changed files with 201 additions and 10 deletions.
@@ -71,6 +71,7 @@
bool HeapShared::_closed_regions_mapped = false;
bool HeapShared::_open_regions_mapped = false;
bool HeapShared::_is_loaded = false;
bool HeapShared::_disable_writing = false;
address HeapShared::_narrow_oop_base;
int HeapShared::_narrow_oop_shift;
DumpedInternedStrings *HeapShared::_dumped_interned_strings = NULL;
@@ -155,10 +155,18 @@ class HeapShared: AllStatic {

// Can this VM write heap regions into the CDS archive? Currently only G1+compressed{oops,cp}
static bool can_write() {
CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
CDS_JAVA_HEAP_ONLY(
if (_disable_writing) {
return false;
}
return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);
)
NOT_CDS_JAVA_HEAP(return false;)
}

static void disable_writing() {
CDS_JAVA_HEAP_ONLY(_disable_writing = true;)
}
// Can this VM map archived heap regions? Currently only G1+compressed{oops,cp}
static bool can_map() {
CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
@@ -188,6 +196,7 @@ class HeapShared: AllStatic {

private:
#if INCLUDE_CDS_JAVA_HEAP
static bool _disable_writing;
static bool _closed_regions_mapped;
static bool _open_regions_mapped;
static bool _is_loaded;
@@ -1253,7 +1253,8 @@ char* ClassLoader::skip_uri_protocol(char* source) {

// Record the shared classpath index and loader type for classes loaded
// by the builtin loaders at dump time.
void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik, const ClassFileStream* stream) {
void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
const ClassFileStream* stream, bool redefined) {
Arguments::assert_is_dumping_archive();
assert(stream != NULL, "sanity");

@@ -1337,10 +1338,10 @@ void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik, const Cl
}
}

// No path entry found for this class. Must be a shared class loaded by the
// No path entry found for this class: most likely a shared class loaded by the
// user defined classloader.
if (classpath_index < 0) {
assert(ik->shared_classpath_index() < 0, "Sanity");
if (classpath_index < 0 && !SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
assert(ik->shared_classpath_index() < 0, "not assigned yet");
ik->set_shared_classpath_index(UNREGISTERED_INDEX);
SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
return;
@@ -1359,7 +1360,7 @@ void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik, const Cl
ik->name()->utf8_length());
assert(file_name != NULL, "invariant");

ClassLoaderExt::record_result(classpath_index, ik);
ClassLoaderExt::record_result(classpath_index, ik, redefined);
}
#endif // INCLUDE_CDS

@@ -365,7 +365,8 @@ class ClassLoader: AllStatic {
static int num_module_path_entries();
static void exit_with_path_failure(const char* error, const char* message);
static char* skip_uri_protocol(char* source);
static void record_result(JavaThread* current, InstanceKlass* ik, const ClassFileStream* stream);
static void record_result(JavaThread* current, InstanceKlass* ik,
const ClassFileStream* stream, bool redefined);
#endif

static char* lookup_vm_options();
@@ -24,6 +24,7 @@

#include "precompiled.hpp"
#include "cds/filemap.hpp"
#include "cds/heapShared.hpp"
#include "classfile/classFileParser.hpp"
#include "classfile/classLoader.inline.hpp"
#include "classfile/classLoaderExt.hpp"
@@ -227,7 +228,7 @@ void ClassLoaderExt::setup_search_paths(JavaThread* current) {
ClassLoaderExt::setup_app_search_path(current);
}

void ClassLoaderExt::record_result(const s2 classpath_index, InstanceKlass* result) {
void ClassLoaderExt::record_result(const s2 classpath_index, InstanceKlass* result, bool redefined) {
Arguments::assert_is_dumping_archive();

// We need to remember where the class comes from during dumping.
@@ -245,4 +246,21 @@ void ClassLoaderExt::record_result(const s2 classpath_index, InstanceKlass* resu
}
result->set_shared_classpath_index(classpath_index);
result->set_shared_class_loader_type(classloader_type);
#if INCLUDE_CDS_JAVA_HEAP
if (DumpSharedSpaces && AllowArchivingWithJavaAgent && classloader_type == ClassLoader::BOOT_LOADER &&
classpath_index < 0 && HeapShared::can_write() && redefined) {
// During static dump, classes for the built-in loaders are always loaded from
// known locations (jimage, classpath or modulepath), so classpath_index should
// always be >= 0.
// The only exception is when a java agent is used during dump time (for testing
// purposes only). If a class is transformed by the agent, the CodeSource of
// this class may point to an unknown location. This may break heap object archiving,
// which requires all the boot classes to be from known locations. This is an
// uncommon scenario (even in test cases). Let's simply disable heap object archiving.
ResourceMark rm;
log_warning(cds)("CDS heap objects cannot be written because class %s maybe modified by ClassFileLoadHook.",
result->external_name());
HeapShared::disable_writing();
}
#endif // INCLUDE_CDS_JAVA_HEAP
}
@@ -111,7 +111,7 @@ class ClassLoaderExt: public ClassLoader { // AllStatic
return _has_non_jar_in_classpath;
}

static void record_result(const s2 classpath_index, InstanceKlass* result);
static void record_result(const s2 classpath_index, InstanceKlass* result, bool redefined);
static void set_has_app_classes() {
_has_app_classes = true;
}
@@ -211,7 +211,7 @@ InstanceKlass* KlassFactory::create_from_stream(ClassFileStream* stream,

#if INCLUDE_CDS
if (Arguments::is_dumping_archive()) {
ClassLoader::record_result(THREAD, result, stream);
ClassLoader::record_result(THREAD, result, stream, old_stream != stream);
}
#endif // INCLUDE_CDS

@@ -354,6 +354,7 @@ hotspot_appcds_dynamic = \
-runtime/cds/appcds/LambdaEagerInit.java \
-runtime/cds/appcds/LambdaProxyClasslist.java \
-runtime/cds/appcds/LambdaVerificationFailedDuringDump.java \
-runtime/cds/appcds/LambdaWithJavaAgent.java \
-runtime/cds/appcds/LambdaWithOldClass.java \
-runtime/cds/appcds/LongClassListPath.java \
-runtime/cds/appcds/LotsOfClasses.java \
@@ -0,0 +1,93 @@
/*
* Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/

/*
* @test
* @bug 8276126
* @summary Test static dumping with java agent transforming a class loaded
* by the boot class loader.
* @requires vm.cds.write.archived.java.heap
* @requires vm.jvmti
* @library /test/lib /test/hotspot/jtreg/runtime/cds/appcds/test-classes
* @compile test-classes/Hello.java
* @compile test-classes/TransformBootClass.java
* @run driver LambdaWithJavaAgent
*/

import jdk.test.lib.cds.CDSOptions;
import jdk.test.lib.cds.CDSTestUtils;
import jdk.test.lib.process.OutputAnalyzer;
import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.helpers.ClassFileInstaller;

public class LambdaWithJavaAgent {

public static String agentClasses[] = {
TransformBootClass.class.getName(),
};

public static void main(String[] args) throws Exception {
String mainClass = Hello.class.getName();
String namePrefix = "lambda-with-java-agent";
JarBuilder.build(namePrefix, mainClass);

String appJar = TestCommon.getTestJar(namePrefix + ".jar");
String classList = namePrefix + ".list";
String archiveName = namePrefix + ".jsa";

String agentJar =
ClassFileInstaller.writeJar("TransformBootClass.jar",
ClassFileInstaller.Manifest.fromSourceFile("test-classes/TransformBootClass.mf"),
agentClasses);
String useJavaAgent = "-javaagent:" + agentJar + "=jdk/internal/math/FDBigInteger";

// dump class list
CDSTestUtils.dumpClassList(classList, "-cp", appJar, mainClass);

// create archive with the class list
CDSOptions opts = (new CDSOptions())
.addPrefix("-XX:ExtraSharedClassListFile=" + classList,
"-cp", appJar,
"-XX:+AllowArchivingWithJavaAgent",
useJavaAgent,
"-Xlog:class+load,cds+class=debug,cds")
.setArchiveName(archiveName);
OutputAnalyzer output = CDSTestUtils.createArchiveAndCheck(opts);
output.shouldContain("CDS heap objects cannot be written because class jdk.internal.math.FDBigInteger maybe modified by ClassFileLoadHook")
.shouldContain("Skipping jdk/internal/math/FDBigInteger: Unsupported location")
.shouldMatch(".class.load.*jdk.internal.math.FDBigInteger.*source.*modules");

// run with archive
CDSOptions runOpts = (new CDSOptions())
.addPrefix("-cp", appJar, "-Xlog:class+load,cds=debug",
"-XX:+AllowArchivingWithJavaAgent",
useJavaAgent)
.setArchiveName(archiveName)
.setUseVersion(false)
.addSuffix(mainClass);
output = CDSTestUtils.runWithArchive(runOpts);
TestCommon.checkExecReturn(output, 0, true,
"Hello source: shared objects file");
}
}
@@ -0,0 +1,62 @@
/*
* Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/

import java.lang.instrument.ClassFileTransformer;
import java.lang.instrument.Instrumentation;
import java.lang.instrument.IllegalClassFormatException;
import java.security.ProtectionDomain;

public class TransformBootClass implements ClassFileTransformer {

static String targetClass = null;

public byte[] transform(ClassLoader loader, String name, Class<?> classBeingRedefined,
ProtectionDomain pd, byte[] buffer) throws IllegalClassFormatException {

if (name.equals(targetClass)) {
System.out.println("Transforming class " + name);
return buffer;
}
return null;
}

private static Instrumentation savedInstrumentation;

public static void premain(String agentArguments, Instrumentation instrumentation) {
System.out.println("TransformBootClass.premain() is called");
instrumentation.addTransformer(new TransformBootClass(), /*canRetransform=*/true);
savedInstrumentation = instrumentation;
if (agentArguments != null) {
targetClass = agentArguments;
}
}

public static Instrumentation getInstrumentation() {
return savedInstrumentation;
}

public static void agentmain(String args, Instrumentation inst) throws Exception {
premain(args, inst);
}
}
@@ -0,0 +1,5 @@
Manifest-Version: 1.0
Premain-Class: TransformBootClass
Agent-Class: TransformBootClass
Can-Retransform-Classes: true
Can-Redefine-Classes: true

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