8267042: bug in monitor locking/unlocking on ARM32 C1 due to uninitialized BasicObjectLock::_displaced_header

[bulasevich]

Hi,

Could we have a review of this change?

The bug was discovered in ARM32 C1 monitor locking/unlocking: the
displaced header is not initialized to the non-zero value which results in deadlock.

The issue was fixed in jdk18, and I want to have this P3 fix in jdk17 as well.

Thanks,
Boris

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Issue

• JDK-8267042: bug in monitor locking/unlocking on ARM32 C1 due to uninitialized BasicObjectLock::_displaced_header ⚠️ Issue is not open.

Reviewers

• Dmitry Samersoff (@dsamersoff - Reviewer)

Contributors

• Chris Cole <chris@sageembedded.com>

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk17 pull/102/head:pull/102
$ git checkout pull/102

Update a local copy of the PR:
$ git checkout pull/102
$ git pull https://git.openjdk.java.net/jdk17 pull/102/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 102

View PR using the GUI difftool:
$ git pr show -t 102

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk17/pull/102.diff

[bulasevich]

/contributor add Chris Cole chris@sageembedded.com

[bridgekeeper]

👋 Welcome back bulasevich! 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]

@bulasevich Could not parse Chris Cole chris@sageembedded.com as a valid contributor.
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[mlbridge]

Webrevs

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[bulasevich]

/contributor add Chris Cole chris@sageembedded.com

[openjdk]

@bulasevich
Contributor Chris Cole <chris@sageembedded.com> successfully added.

[openjdk]

@bulasevich 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:

8267042: bug in monitor locking/unlocking on ARM32 C1 due to uninitialized BasicObjectLock::_displaced_header

Co-authored-by: Chris Cole <chris@sageembedded.com>
Reviewed-by: dsamersoff

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:

• b358b54: 8269063: Build failure due to VerifyReceiverTypes was not declared after JDK-8268405
• b8f073b: 8268316: Typo in JFR jdk.Deserialization event
• b9d7337: 8268638: semaphores of AsyncLogWriter may be broken when JVM is exiting.
• 8caeca0: 8264775: ClhsdbFindPC still fails with java.lang.RuntimeException: 'In java stack' missing from stdout/stderr

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.

[bulasevich]

/integrate

[openjdk]

Going to push as commit c294ae4.
Since your change was applied there have been 4 commits pushed to the master branch:

• b358b54: 8269063: Build failure due to VerifyReceiverTypes was not declared after JDK-8268405
• b8f073b: 8268316: Typo in JFR jdk.Deserialization event
• b9d7337: 8268638: semaphores of AsyncLogWriter may be broken when JVM is exiting.
• 8caeca0: 8264775: ClhsdbFindPC still fails with java.lang.RuntimeException: 'In java stack' missing from stdout/stderr

Your commit was automatically rebased without conflicts.

[openjdk]

@bulasevich Pushed as commit c294ae4.

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