8323086: Shenandoah: Heap could be corrupted by oom during evacuation

[earthling-amzn]

When the load reference barrier is unable to evacuate an object, it initiates a degenerated cycle, and allows the from-space reference past the barrier. The degenerated cycle is meant to patch up these references, but if the reference is written above the update-watermark, it will be missed.

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Progress

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Issue

• JDK-8323086: Shenandoah: Heap could be corrupted by oom during evacuation (Bug - P4)

Reviewers

• Kelvin Nilsen (@kdnilsen - no project role)
• Aleksey Shipilev (@shipilev - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back wkemper! 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]

@earthling-amzn The following labels will be automatically applied to this pull request:

• hotspot-gc
• shenandoah

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[mlbridge]

Webrevs

• 00: Full (dd63eb61)

[kdnilsen]

Debugging of JDK-8322804 suggests that this is the necessary fix.

[shipilev]

Looks fine.

[openjdk]

@earthling-amzn 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:

8323086: Shenandoah: Heap could be corrupted by oom during evacuation

Reviewed-by: kdnilsen, 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 20 new commits pushed to the master branch:

• 827c71d: 8310190: C2 SuperWord: AlignVector is broken, generates misaligned packs
• 2acb5bd: 8322790: RISC-V: Tune costs for shuffles with no conversion
• c8fa3e2: 8320310: CompiledMethod::has_monitors flag can be incorrect
• 57a65fe: 8322003: JShell - Incorrect type inference in lists of records implementing interfaces
• c90768c: 8318444: Write details about compilation bailouts into crash reports
• 29397d2: 8320317: ObjectMonitor NotRunnable is not really an optimization
• fc04750: 8321371: SpinPause() not implemented for bsd_aarch64/macOS
• 458e563: 8310711: [IR Framework] Remove safepoint while printing handling
• 71aac7a: 8276809: java/awt/font/JNICheck/FreeTypeScalerJNICheck.java shows JNI warning on Windows
• 09c6c4f: 8322489: 22-b27: Up to 7% regression in all Footprint3-*-G1/ZGC
• ... and 10 more: https://git.openjdk.org/jdk/compare/46965a096ce74d9375df36a3a66107e9295cc180...master

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.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@shipilev) but any other Committer may sponsor as well.

➡️ 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).

[earthling-amzn]

/integrate

[openjdk]

@earthling-amzn
Your change (at version dd63eb6) is now ready to be sponsored by a Committer.

[shipilev]

/sponsor

[openjdk]

Going to push as commit c4a83bd.
Since your change was applied there have been 20 commits pushed to the master branch:

• 827c71d: 8310190: C2 SuperWord: AlignVector is broken, generates misaligned packs
• 2acb5bd: 8322790: RISC-V: Tune costs for shuffles with no conversion
• c8fa3e2: 8320310: CompiledMethod::has_monitors flag can be incorrect
• 57a65fe: 8322003: JShell - Incorrect type inference in lists of records implementing interfaces
• c90768c: 8318444: Write details about compilation bailouts into crash reports
• 29397d2: 8320317: ObjectMonitor NotRunnable is not really an optimization
• fc04750: 8321371: SpinPause() not implemented for bsd_aarch64/macOS
• 458e563: 8310711: [IR Framework] Remove safepoint while printing handling
• 71aac7a: 8276809: java/awt/font/JNICheck/FreeTypeScalerJNICheck.java shows JNI warning on Windows
• 09c6c4f: 8322489: 22-b27: Up to 7% regression in all Footprint3-*-G1/ZGC
• ... and 10 more: https://git.openjdk.org/jdk/compare/46965a096ce74d9375df36a3a66107e9295cc180...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev @earthling-amzn Pushed as commit c4a83bd.

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