8273894: ConcurrentModificationException raised every time ReferralsCache drops referral

[jaikiran]

Can I please get a review for this change which proposes to fix the issue noted in https://bugs.openjdk.java.net/browse/JDK-8273894?

Given the nature of the code in ReferralsCache, I haven't been able to add a new jtreg test case to reproduce the issue and verify this fix. Just to be sure that this change indeed fixes a reproducible issue, I replicated that code in a pretty trivial Java application and then verified a similar fix.

Existing tests in test/jdk/sun/security/krb5/auto/ continue to pass after this change.

---

Progress

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Issue

• JDK-8273894: ConcurrentModificationException raised every time ReferralsCache drops referral

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/5632/head:pull/5632
$ git checkout pull/5632

Update a local copy of the PR:
$ git checkout pull/5632
$ git pull https://git.openjdk.java.net/jdk pull/5632/head

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Checkout this PR locally:
$ git pr checkout 5632

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$ git pr show -t 5632

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https://git.openjdk.java.net/jdk/pull/5632.diff

[bridgekeeper]

👋 Welcome back jpai! 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.

[openjdk]

@jaikiran The following label will be automatically applied to this pull request:

• security

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[mlbridge]

Webrevs

• 00: Full (296761df)

[shipilev]

This seems to trace back all the way to initial integration with JDK-8215032. The bug and the fix are understandable. Looks good! @martinuy, who I think is the original author, should ack too.

[openjdk]

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

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8273894: ConcurrentModificationException raised every time ReferralsCache drops referral

Reviewed-by: shade

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 4 new commits pushed to the master branch:

• 51085b5: 8274054: Add custom enqueue calls during reference processing
• c77ebe8: 8274060: C2: Incorrect computation after JDK-8273454
• d9872ba: 8273590: Move helper classes in G1 post evacuation sub tasks to cpp files
• 688b3fe: 8274070: Rectify problemlist platform for failing test on macos12

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[martinuy]

Hi,

Thanks for contributing this fix. I'm not an official Reviewer for JDK main line but your fix looks good to me.

Martin.-

[jaikiran]

Thank you Martin and Aleksey for the reviews.

[jaikiran]

/integrate

[openjdk]

Going to push as commit 2166ed1.
Since your change was applied there have been 24 commits pushed to the master branch:

• 1c6fa11: 8273979: move some os time related functions to os_posix for POSIX platforms
• 45adc92: 8273578: javax/swing/JMenu/4515762/bug4515762.java fails on macOS 12
• 0fbbe4c: 8274033: Some tier-4 CDS EpsilonGC tests throw OOM
• 9d3379b: 8267356: AArch64: Vector API SVE codegen support
• 6031388: 8273714: jdk/jfr/api/consumer/TestRecordedFrame.java still times out after JDK-8273047
• 8821b00: 8205137: Remove Applet support from SwingSet2
• 57fe11c: 8274120: [JVMCI] CompileBroker should resolve parameter types for JVMCI compiles
• 81d4164: 8272759: (fc) java/nio/channels/FileChannel/Transfer2GPlus.java failed in timeout
• da38ced: 8271602: Add Math.ceilDiv() family parallel to Math.floorDiv() family
• d39aad9: 8273924: ArrayIndexOutOfBoundsException thrown in java.util.JapaneseImperialCalendar.add()
• ... and 14 more: https://git.openjdk.java.net/jdk/compare/eeaf43b229941f49326ed6d0f37e77f6f0ce5409...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jaikiran Pushed as commit 2166ed1.

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