8267842: SIGSEGV in get_current_contended_monitor

[TheRealMDoerr]

Fix for crashes in get_current_contended_monitor which were observed in 17 due to concurrent modification of memory locations which are not declared volatile. See bug for details.

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Progress

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Issue

• JDK-8267842: SIGSEGV in get_current_contended_monitor

Reviewers

• Daniel D. Daugherty (@dcubed-ojdk - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk16u pull/125/head:pull/125
$ git checkout pull/125

Update a local copy of the PR:
$ git checkout pull/125
$ git pull https://git.openjdk.java.net/jdk16u pull/125/head

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$ git pr checkout 125

View PR using the GUI difftool:
$ git pr show -t 125

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Download this PR as a diff file:
https://git.openjdk.java.net/jdk16u/pull/125.diff

[bridgekeeper]

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[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (a254862c)

[dcubed-ojdk]

Looks like a reasonable backport.

[openjdk]

@TheRealMDoerr 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:

8267842: SIGSEGV in get_current_contended_monitor

Reviewed-by: dcubed

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 1 new commit pushed to the master branch:

• a680794: 8261354: SIGSEGV at MethodIteratorHost

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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[TheRealMDoerr]

Thanks for the review!
/integrate

[openjdk]

@TheRealMDoerr Since your change was applied there have been 2 commits pushed to the master branch:

• 53dd617: 8260401: StackOverflowError on open WindowsPreferences
• a680794: 8261354: SIGSEGV at MethodIteratorHost

Your commit was automatically rebased without conflicts.

Pushed as commit 6f948a7.

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