8348562: ZGC: segmentation fault due to missing node type check in barrier elision analysis

[TheRealMDoerr]

Clean backport of JDK-8348562. It only adds a null check + bailout where the current implementation crashes with SIGSEGV.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8348562: ZGC: segmentation fault due to missing node type check in barrier elision analysis (Bug - P2)

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer)
• Tobias Hartmann (@TobiHartmann - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/23422/head:pull/23422
$ git checkout pull/23422

Update a local copy of the PR:
$ git checkout pull/23422
$ git pull https://git.openjdk.org/jdk.git pull/23422/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 23422

View PR using the GUI difftool:
$ git pr show -t 23422

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/23422.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back mdoerr! A progress list of the required criteria for merging this PR into jdk24 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[TheRealMDoerr]

/approval request It was suggested to target 24 instead of 24u since it is now P2. If it gets approved I'll close the 24u version.

[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:

8348562: ZGC: segmentation fault due to missing node type check in barrier elision analysis

Reviewed-by: kvn, thartmann

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 jdk24 branch:

• 47c15b5: 8348658: [AArch64] The node limit in compiler/codegen/TestMatcherClone.java is too strict

Please see this link for an up-to-date comparison between the source branch of this pull request and the jdk24 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 jdk24 branch, type /integrate in a new comment.

[openjdk]

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

[openjdk]

@TheRealMDoerr Changes in this repository do not require maintainer approval.

[openjdk]

@TheRealMDoerr The following label will be automatically applied to this pull request:

• hotspot-gc

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 00: Full (e2cfb377)

[TheRealMDoerr]

@TobiHartmann This is the jdk24 backport. Please take a look.

[vnkozlov]

The fix was requested for JDK 24 update (jdk24u repository) not for JDK 24 branch which this change is based on (if I see this correctly).

[TheRealMDoerr]

@vnkozlov I had originally targeted 24u, but Tobias has reclassified it as P2, so this is the new PR. I will close the other one if this one gets approved.

[vnkozlov]

@TheRealMDoerr you need new Fix request and approval for JDK 24 in bug report.

[TheRealMDoerr]

@TheRealMDoerr you need new Fix request and approval for JDK 24 in bug report.

JDK24 requires a review instead of a maintainer approval. See Skara messages above.

[vnkozlov]

@TheRealMDoerr you need new Fix request and approval for JDK 24 in bug report.

JDK24 requires a review instead of a maintainer approval. See Skara messages above.

We are in RDP 2 phase - you need approval for fixes there: https://openjdk.org/jeps/3#rdp-2

[vnkozlov]

To clarify. It is different approval from approval for update release.

[TheRealMDoerr]

Ok. Thanks! I've created the approval request manually. Skara doesn't support it.

[vnkozlov]

Ok. Thanks! I've created the approval request manually. Skara doesn't support it.

Yes, it is manual process - you need to add label and comment to main bug report.

[vnkozlov]

@TheRealMDoerr Please, add fix request comment too. You can copy jdk24u request.

[vnkozlov]

Good. I approved request as Area Lead. Formalities are done ;^)
Now we can review and integrate this into JDK 24.

[vnkozlov]

Looks good.

[TobiHartmann]

Looks good to me too.

[TheRealMDoerr]

Thanks for the reviews and for the assistance!

[TheRealMDoerr]

/integrate

[openjdk]

Going to push as commit b1659e3.
Since your change was applied there has been 1 commit pushed to the jdk24 branch:

• 47c15b5: 8348658: [AArch64] The node limit in compiler/codegen/TestMatcherClone.java is too strict

Your commit was automatically rebased without conflicts.

[openjdk]

@TheRealMDoerr Pushed as commit b1659e3.

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