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@JornVernee JornVernee commented Nov 7, 2025

The existing test uses the JVMTI VMStart callback to look up a class. This works when using CDS, because the class is already available, but because VMStart is called while the VM is still being initialized, it fails to find the target class when CDS is turned off.

Instead, the VMInit callback should be used instead, which runs after the VM has been initialized. This patch does this. Additionally, it delays the call to allocate OTHER_SEGMENT. If we call FindClass during VMInit, the <clinit> of the class will run, which then ends up calling checkValidStateRaw as a result of allocating OTHER_SEGMENT, and we get to our method exit event code before the target class and method ID have been initialized.

As a side note: I had know about the difference between VMInit and VMStart, and had actually intended to use VMInit in the first place, but I seem to have gotten the two confused, because they are listed in reverse chronological order in the list under 'Set Event Notification Mode' in the JVMTI spec (https://docs.oracle.com/en/java/javase/25/docs/specs/jvmti.html#SetEventNotificationMode).


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  • JDK-8371474: Wrong object class or methodID passed to JNI call in TestSharedCloseJvmti with -Xshare:off (Bug - P4)

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👋 Welcome back jvernee! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

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@JornVernee This change now passes all automated pre-integration checks.

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8371474: Wrong object class or methodID passed to JNI call in TestSharedCloseJvmti with -Xshare:off

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@openjdk openjdk bot added the core-libs core-libs-dev@openjdk.org label Nov 7, 2025
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@JornVernee JornVernee marked this pull request as ready for review November 8, 2025 01:14
@openjdk openjdk bot added the rfr Pull request is ready for review label Nov 8, 2025
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Yes, using VMInit so the code executes when the VM is fully initialized is right.

@openjdk openjdk bot added the ready Pull request is ready to be integrated label Nov 8, 2025
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