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

[chrishcole]

---

Progress

• Change must not contain extraneous whitespace
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Issue

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

Reviewing

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[bridgekeeper]

Hi @chrishcole, welcome to this OpenJDK project and thanks for contributing!

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[openjdk]

This backport pull request has now been updated with issue from the original commit.

[chrishcole]

/covered

[bridgekeeper]

Thank you! Please allow for a few business days to verify that your employer has signed the OCA. Also, please note that pull requests that are pending an OCA check will not usually be evaluated, so your patience is appreciated!

[TheRealMDoerr]

I've requested backport approval in the JBS issue. It can get integrated once OCA is verified and the backport approved.

[chrishcole]

@TheRealMDoerr great thanks for the information and help.

My company Sage Embedded Software LLC has signed the OCA, if there is any additional information required let me know.

I have tested this change by running the JCK with ARM32 build (without this fix a get a couple test cases that hang). I have also verified that included jtreg test case passes for x86, aarch64 and arm32 builds of jdk11.

I just remembered that in jdk11 there is the non-default --with-cpu-port=arm64 that is also impacted by this bug and would require additional changes to the "#ifdef AARCH64" blocks of the changed lines of code. I tried building --with-cpu-port=arm64 and it is very broken by various commits over the last few years. So I assume this port has been abandoned and not supported for jdk11 any more. So I will not worry about these extra changes. The default "aarch64" and non-ARM ports are NOT impacted by this issue, but the arm32 port is.

Thanks again,
Chris Cole
Sage Embedded Software LLC

[openjdk]

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

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

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 9 new commits pushed to the master branch:

• 2696643: 8254967: com.sun.net.HttpsServer spins on TLS session close
• 1e1a2c4: 8270556: Exclude security/infra/java/security/cert/CertPathValidator/certification/LetsEncryptCA
• 10bbe2f: 8263531: Remove unused buffer int
• dff3b7f: 8267459: Pasting Unicode characters into JShell does not work.
• 2252165: 8268362: [REDO] C2 crash when compile negative Arrays.copyOf length after loop
• 8008d33: 8269304: Regression ~5% in 2005 in b27
• 7a61e03: 8268347: C2: nested locks optimization may create unbalanced monitor enter/exit code
• 93f952c: 8269882: stack-use-after-scope in NewObjectA
• c9a8220: 8268620: InfiniteLoopException test may fail on x86 platforms

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.

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➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[mlbridge]

Webrevs

• 00: Full (2f48e1c3)

[chrishcole]

/integrate

[openjdk]

@chrishcole
Your change (at version 2f48e1c) is now ready to be sponsored by a Committer.

[TheRealMDoerr]

/sponsor

[openjdk]

Going to push as commit 240ef44.
Since your change was applied there have been 9 commits pushed to the master branch:

• 2696643: 8254967: com.sun.net.HttpsServer spins on TLS session close
• 1e1a2c4: 8270556: Exclude security/infra/java/security/cert/CertPathValidator/certification/LetsEncryptCA
• 10bbe2f: 8263531: Remove unused buffer int
• dff3b7f: 8267459: Pasting Unicode characters into JShell does not work.
• 2252165: 8268362: [REDO] C2 crash when compile negative Arrays.copyOf length after loop
• 8008d33: 8269304: Regression ~5% in 2005 in b27
• 7a61e03: 8268347: C2: nested locks optimization may create unbalanced monitor enter/exit code
• 93f952c: 8269882: stack-use-after-scope in NewObjectA
• c9a8220: 8268620: InfiniteLoopException test may fail on x86 platforms

Your commit was automatically rebased without conflicts.

[openjdk]

@TheRealMDoerr @chrishcole Pushed as commit 240ef44.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.