8331735: UpcallLinker::on_exit races with GC when copying frame anchor

[gnu-andrew]

Clean backport of a fix for a race condition in code adapted from JavaCallWrapper for the FFM API. This is more visible in 22 and later, where FFM is fully supported and the OpenType implementation using HarfBuzz has been ported to use it. However, the copy in the native state seems to have been introduced as far back as JDK-8269240 in 17 when the JavaCallWrapper code was ported to what was then universalUpcallHandler.cpp.

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8343144 needs maintainer approval
• JDK-8286875 needs maintainer approval
• JDK-8331735 needs maintainer approval

Issues

• JDK-8331735: UpcallLinker::on_exit races with GC when copying frame anchor (Bug - P3 - Approved)
• JDK-8343144: UpcallLinker::on_entry racingly clears pending exception with GC safepoints (Bug - P4 - Approved)
• JDK-8286875: ProgrammableUpcallHandler::on_entry/on_exit access thread fields from native (Bug - P4 - Approved)

Reviewing

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[bridgekeeper]

👋 Welcome back andrew! 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]

@gnu-andrew 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:

8331735: UpcallLinker::on_exit races with GC when copying frame anchor
8343144: UpcallLinker::on_entry racingly clears pending exception with GC safepoints
8286875: ProgrammableUpcallHandler::on_entry/on_exit access thread fields from native

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 14 new commits pushed to the master branch:

• 4159e88: 8350650: Bump update version for OpenJDK: jdk-21.0.8
• 5806906: 8317808: HTTP/2 stream cancelImpl may leave subscriber registered
• 951453e: 8344581: [TESTBUG] java/awt/Robot/ScreenCaptureRobotTest.java failing on macOS
• 2f9840c: 8339356: Test javax/net/ssl/SSLSocket/Tls13PacketSize.java failed with java.net.SocketException: An established connection was aborted by the software in your host machine
• 68ad843: 8342635: javax/swing/JFileChooser/FileSystemView/WindowsDefaultIconSizeTest.java creates tmp file in src dir
• 335b2f5: 8349039: Adjust exception No type named in database
• d02ad34: 8327476: Upgrade JLine to 3.26.1
• 9c26323: 8349729: [21u] AIX jtreg tests fail to compile with qvisibility=hidden
• 69192fe: 8348675: TrayIcon tests fail in Ubuntu 24.10 Wayland
• ed0c9d3: 8346828: javax/swing/JScrollBar/4865918/bug4865918.java still fails in CI
• ... and 4 more: https://git.openjdk.org/jdk21u-dev/compare/1b49a33e73ba40058462e0d8269d941386d94a30...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.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

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

[openjdk]

⚠️ @gnu-andrew This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (ce0ab884)

[gnu-andrew]

/approval request Clean backport of a fix for a race condition in the FFM API. Can lead to crashes when the FFM code manipulates a frame anchor in native mode, which the GC does not expect to happen. Fix is to move the frame anchor copying to Java mode, where the GC will wait for the thread to get to a safepoint. Risk to other code is low as the UpcallLinker is only used by FFM.

[openjdk]

@gnu-andrew
8331735: The approval request has been created successfully.
8343144: The approval request has been created successfully.
8286875: The approval request has been created successfully.

[GoeLin]

@gnu-andrew, you might want to push this, today 18:00 CET the last automatic merge from jdk21u-dev to jdk21u will happen.

[gnu-andrew]

@gnu-andrew, you might want to push this, today 18:00 CET the last automatic merge from jdk21u-dev to jdk21u will happen.

Ah, sorry, I got my dates mixed up and thought that was next week. I've been away the first half of this week, so only been able to get back to this today.

[gnu-andrew]

/integrate

[openjdk]

Going to push as commit 91457e6.
Since your change was applied there have been 16 commits pushed to the master branch:

• ae47d99: 8346082: Output JVMTI agent information in hserr files
• b942b5e: 8345146: [PPC64] Make intrinsic conversions between bit representations of half precision values and floats
• 4159e88: 8350650: Bump update version for OpenJDK: jdk-21.0.8
• 5806906: 8317808: HTTP/2 stream cancelImpl may leave subscriber registered
• 951453e: 8344581: [TESTBUG] java/awt/Robot/ScreenCaptureRobotTest.java failing on macOS
• 2f9840c: 8339356: Test javax/net/ssl/SSLSocket/Tls13PacketSize.java failed with java.net.SocketException: An established connection was aborted by the software in your host machine
• 68ad843: 8342635: javax/swing/JFileChooser/FileSystemView/WindowsDefaultIconSizeTest.java creates tmp file in src dir
• 335b2f5: 8349039: Adjust exception No type named in database
• d02ad34: 8327476: Upgrade JLine to 3.26.1
• 9c26323: 8349729: [21u] AIX jtreg tests fail to compile with qvisibility=hidden
• ... and 6 more: https://git.openjdk.org/jdk21u-dev/compare/1b49a33e73ba40058462e0d8269d941386d94a30...master

Your commit was automatically rebased without conflicts.

[openjdk]

@gnu-andrew Pushed as commit 91457e6.

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