8287073: NPE from CgroupV2Subsystem.getInstance()

[jerboaa]

Clean backport. Issue present in 17u too and low risk fix. Regression test in JDK-8287663 which I intend to backport too.

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Progress

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Issue

• JDK-8287073: NPE from CgroupV2Subsystem.getInstance()

Reviewing

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$ git checkout pull/456

Update a local copy of the PR:
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$ git pull https://git.openjdk.java.net/jdk17u-dev pull/456/head

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$ git pr checkout 456

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https://git.openjdk.java.net/jdk17u-dev/pull/456.diff

[bridgekeeper]

👋 Welcome back sgehwolf! 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]

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

[openjdk]

@jerboaa 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:

8287073: NPE from CgroupV2Subsystem.getInstance()

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[mlbridge]

Webrevs

• 00: Full (f07ac954)

[jerboaa]

/integrate

[openjdk]

Going to push as commit cb88133.
Since your change was applied there have been 7 commits pushed to the master branch:

• 292d90d: 8178969: [TESTBUG] Wrong reporting of gc/g1/humongousObjects/TestHeapCounters test.
• a081e4a: 8283441: C2: segmentation fault in ciMethodBlocks::make_block_at(int)
• aa3d2f7: 8172065: javax/swing/JTree/4908142/bug4908142.java The selected index should be "aad"
• 66cdd6e: 8284694: Avoid evaluating SSLAlgorithmConstraints twice
• 92d617f: 8159694: HiDPI, Unity, java/awt/dnd/DropTargetEnterExitTest/MissedDragExitTest.java
• 667582d: 8285820: C2: LCM prioritizes locally dependent CreateEx nodes over projections after 8270090
• 2da3752: 8270090: C2: LCM may prioritize CheckCastPP nodes over projections

Your commit was automatically rebased without conflicts.

[openjdk]

@jerboaa Pushed as commit cb88133.

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