8299790: os::print_hex_dump is racy

[tstuefe]

Hi all,

This pull request contains a backport of commit 8f28809a from the openjdk/jdk repository.

The commit being backported was authored by Thomas Stuefe on 10 Aug 2023 and was reviewed by Aleksey Shipilev and David Holmes.

Thanks!

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8299790 needs maintainer approval

Issue

• JDK-8299790: os::print_hex_dump is racy (Bug - P4 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/824/head:pull/824
$ git checkout pull/824

Update a local copy of the PR:
$ git checkout pull/824
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/824/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 824

View PR using the GUI difftool:
$ git pr show -t 824

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/824.diff

Webrev

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[bridgekeeper]

👋 Welcome back stuefe! 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]

@tstuefe 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:

8299790: os::print_hex_dump is racy

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 42 new commits pushed to the master branch:

• d0a1fbd: 8331405: Shenandoah: Optimize ShenandoahLock with TTAS
• e459fe0: 8312200: Fix Parse::catch_call_exceptions memory leak
• a98bd60: 8315422: getSoTimeout() would be in try block in SSLSocketImpl
• 69aab6a: 8333542: Breakpoint in parallel code does not work
• 9176fa2: 8332818: ubsan: archiveHeapLoader.cpp:70:27: runtime error: applying non-zero offset 18446744073707454464 to null pointer
• 021e881: 8334418: Update IANA Language Subtag Registry to Version 2024-06-14
• 7e5d30f: 8334123: log the opening of Type 1 fonts
• 9a02aa6: 8333887: ubsan: unsafe.cpp:247:13: runtime error: store to null pointer of type 'volatile int'
• be519cd: 8327424: ProblemList serviceability/sa/TestJmapCore.java on all platforms with ZGC
• 4e95699: 8328273: sun/management/jmxremote/bootstrap/RmiRegistrySslTest.java failed with java.rmi.server.ExportException: Port already in use
• ... and 32 more: https://git.openjdk.org/jdk21u-dev/compare/4f8222994027f778a32aa50312caaf1bf8aa1641...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 issue from the original commit.

[openjdk]

⚠️ @tstuefe 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 (30f483f8)

[tstuefe]

/approval request I would like to downport this fix since this is a bug (admittedly, with limited consequences: printing potentially unreadable sections should only done during hs-err printing, so all it would do is mess up hs-err files). But it is also a prerequisite for downporting JDK-8334738, which would be very useful to have, e.g. in the context of dealing with reproducible builds and CDS dumps.

The fix itself is low risk, but it introduced a test error for big-endian platforms, which was fixed subsequently with https://bugs.openjdk.org/browse/JDK-8314163. I will backport that one without delay once this patch is pushed.

[openjdk]

@tstuefe
8299790: The approval request has been created successfully.

[tstuefe]

Got approval
/integrate

[openjdk]

Going to push as commit 0506f4c.
Since your change was applied there have been 42 commits pushed to the master branch:

• d0a1fbd: 8331405: Shenandoah: Optimize ShenandoahLock with TTAS
• e459fe0: 8312200: Fix Parse::catch_call_exceptions memory leak
• a98bd60: 8315422: getSoTimeout() would be in try block in SSLSocketImpl
• 69aab6a: 8333542: Breakpoint in parallel code does not work
• 9176fa2: 8332818: ubsan: archiveHeapLoader.cpp:70:27: runtime error: applying non-zero offset 18446744073707454464 to null pointer
• 021e881: 8334418: Update IANA Language Subtag Registry to Version 2024-06-14
• 7e5d30f: 8334123: log the opening of Type 1 fonts
• 9a02aa6: 8333887: ubsan: unsafe.cpp:247:13: runtime error: store to null pointer of type 'volatile int'
• be519cd: 8327424: ProblemList serviceability/sa/TestJmapCore.java on all platforms with ZGC
• 4e95699: 8328273: sun/management/jmxremote/bootstrap/RmiRegistrySslTest.java failed with java.rmi.server.ExportException: Port already in use
• ... and 32 more: https://git.openjdk.org/jdk21u-dev/compare/4f8222994027f778a32aa50312caaf1bf8aa1641...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tstuefe Pushed as commit 0506f4c.

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