8309663: test fails "assert(check_alignment(result)) failed: address not aligned: 0x00000008baadbabe"

[shipilev]

Clean backport to fix a corner case in JVMTI + concurrent GCs.

Additional testing:

• macos-aarch64-server-fastdebug, jdk_loom hotspot_loom
• linux-x86_64-server-fastdebug, tier1 tier2 tier3
• linux-x86_64-server-fastdebug, tier1 tier2 tier3 with -XX:+UseShenandoahGC

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8309663 needs maintainer approval

Issue

• JDK-8309663: test fails "assert(check_alignment(result)) failed: address not aligned: 0x00000008baadbabe" (Bug - P4 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u.git pull/253/head:pull/253
$ git checkout pull/253

Update a local copy of the PR:
$ git checkout pull/253
$ git pull https://git.openjdk.org/jdk21u.git pull/253/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 253

View PR using the GUI difftool:
$ git pr show -t 253

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u/pull/253.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back shade! 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]

⚠️ @shipilev 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 (89ba316f)

[shipilev]

/approval request Clean backport to fix a corner case in JVMTI + concurrent GCs.

[openjdk]

@shipilev
8309663: The approval request has been created successfully.

[openjdk]

@shipilev 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:

8309663: test fails "assert(check_alignment(result)) failed: address not aligned: 0x00000008baadbabe"

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 18 new commits pushed to the master branch:

• e796082: Merge
• 060c4f7: 8317121: vector_masked_load instruction is moved too early after JDK-8286941
• 587a7ca: Merge
• 9ebc5ac: 8314649: Enhanced archival support redux
• 86a1699: 8309966: Enhanced TLS connections
• 5f5061f: 8312248: Enhanced archival support redux
• 091ebfa: 8311682: Change milestone to fcs for all releases
• b293106: 8286503: Enhance security classes
• 8b58728: Merge remote-tracking branch 'jdk21u/master'
• 0ca350d: 8297856: Improve handling of Bidi characters
• ... and 8 more: https://git.openjdk.org/jdk21u/compare/65941f8d31094511a5bf8dff110645f83cfc07ef...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.

[shipilev]

/integrate

[openjdk]

Going to push as commit 87ca293.
Since your change was applied there have been 19 commits pushed to the master branch:

• 55d0c79: 8316929: Shenandoah: Shenandoah degenerated GC and full GC need to cleanup old OopMapCache entries
• e796082: Merge
• 060c4f7: 8317121: vector_masked_load instruction is moved too early after JDK-8286941
• 587a7ca: Merge
• 9ebc5ac: 8314649: Enhanced archival support redux
• 86a1699: 8309966: Enhanced TLS connections
• 5f5061f: 8312248: Enhanced archival support redux
• 091ebfa: 8311682: Change milestone to fcs for all releases
• b293106: 8286503: Enhance security classes
• 8b58728: Merge remote-tracking branch 'jdk21u/master'
• ... and 9 more: https://git.openjdk.org/jdk21u/compare/65941f8d31094511a5bf8dff110645f83cfc07ef...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev Pushed as commit 87ca293.

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