AOT testing StackWalkerTest_0 testClassLoaderName AssertionError: Wrong classloader name expected [TestMyloaderInstance] but found [null]

[pshipton]

https://openj9-jenkins.osuosl.org/job/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/294

Still failing in the latest builds, on both tested versions jdk11 and jdk17.
https://openj9-jenkins.osuosl.org/job/Pipeline-Build-Test-AOT/327/

StackWalkerTest_0

12:51:01  OpenJDK Runtime Environment (build 11.0.25-internal+0-adhoc.****.BuildJDK11s390xlinuxaotPersonal)
12:51:01  Eclipse OpenJ9 VM (build master-16ab797349b, JRE 11 Linux s390x-64-Bit Compressed References 20240924_300 (JIT enabled, AOT enabled)
12:51:01  OpenJ9   - 16ab797349b
12:51:01  OMR      - 611c142075f
12:51:01  JCL      - 3d65f3fd583 based on jdk-11.0.25+6)

18:35:20  "/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/jdkbinary/j2sdk-image/bin/java" -Xshareclasses:name=test_aot -Xscmx400M -Xscmaxaot256m  -Xint  \
18:35:20  -cp "/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/aqa-tests/TKG/../../jvmtest/TestConfig/resources:/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/../../testDependency/lib/testng.jar:/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/../../testDependency/lib/jcommander.jar:/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/aqa-tests/TKG/../../jvmtest/functional/Java9andUp/GeneralTest.jar" \
18:35:20  org.testng.TestNG -d "/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/aqa-tests/TKG/../TKG/output_17271977954965/StackWalkerTest_0_AOT_ITER_$aotItercnt" "/home/jenkins/workspace/Test_openjdk11_j9_extended.functional_s390x_linux_aot_Personal_testList_1/aqa-tests/TKG/../../jvmtest/functional/Java9andUp/testng.xml" -testnames StackWalkerTest \
18:35:20  -groups level.extended \
18:35:20  -excludegroups d.*.linux_390-64,d.*.arch.390,d.*.os.linux,d.*.bits.64,d.*.generic-all

18:35:20  === AOT ITERATION 1 ===

18:35:22  FAILED: testClassLoaderName
18:35:22  java.lang.AssertionError: Wrong classloader name expected [TestMyloaderInstance] but found [null]
18:35:22  	at org.testng.Assert.fail(Assert.java:96)
18:35:22  	at org.testng.Assert.failNotEquals(Assert.java:776)
18:35:22  	at org.testng.Assert.assertEqualsImpl(Assert.java:132)
18:35:22  	at org.testng.Assert.assertEquals(Assert.java:118)
18:35:22  	at org.testng.Assert.assertEquals(Assert.java:453)
18:35:22  	at org.openj9.test.stackWalker.MyRunnable.run(MyRunnable.java:45)
18:35:22  	at org.openj9.test.stackWalker.StackWalkerTest.testClassLoaderName(StackWalkerTest.java:243)

Last known working build

07:17:28  OpenJDK Runtime Environment (build 11.0.25-internal+0-adhoc.****.BuildJDK11s390xlinuxaotPersonal)
07:17:28  Eclipse OpenJ9 VM (build master-0985ff3f82b, JRE 11 Linux s390x-64-Bit Compressed References 20240917_298 (JIT enabled, AOT enabled)
07:17:28  OpenJ9   - 0985ff3f82b
07:17:28  OMR      - 10fdf657a92
07:17:28  JCL      - 5998a93447c based on jdk-11.0.25+6)

0985ff3...16ab797
eclipse-openj9/openj9-omr@10fdf65...611c142

[github-actions]

Issue Number: 20368
Status: Open
Recommended Components: comp:test, comp:vm, comp:gc
Recommended Assignees: llxia, jasonfengj9, pshipton

[pshipton]

@hangshao0 can you pls take a look. It's failing in the first run, so not AOT, but running with -Xshareclasses:name=test_aot, which is different from the nightly builds where it doesn't fail.

[hangshao0]

It is likely due to #20169.

Before this change findJ9ClassForROMClass() was able to change the resultClassLoader from bootstrap class loader to testMyloader so the test passed. I believe #20169 changed the behaviour of findJ9ClassForROMClass() somehow that resultClassLoader is not updated to testMyloader. classloader name null means it still points to bootstrap class loader.

@theresa-m Could you take a look at this ?
You can verify things simply running the test with option -Xshareclasses:name=test_aot.

[hangshao0]

I don't see the code updating the resultClassLoader if class is found in the hashtable:

openj9/runtime/vm/exceptiondescribe.c

Lines 259 to 262 in d38a818

	if (NULL != resultEntry) {
	ret = resultEntry->ramClass;
	goto done;
	}

[pshipton]

Do you think this is something we should fix in 0.48?

[theresa-m]

I will take a look.

[hangshao0]

Do you think this is something we should fix in 0.48?

Yes, if the final fix is small and has low risk.

[theresa-m]

I tested StackWalkerTest_0 locally with -Xshareclasses:name=test_aot and it passes with #20371.

[github-actions]

Issue Number: 20368
Status: Closed
Actual Components: comp:vm, test failure
Actual Assignees: No one :(
PR Assignees: theresa-m, theresa-m