8251257: NMT: jcmd VM.native_memory scale=1 crashes target VM

[kvergizova]

I'd like to backport JDK-8251257 to 15u for parity with 11u.
The patch applies cleanly.
Tested with tier1 and nmt tests.

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Issue

• JDK-8251257: NMT: jcmd VM.native_memory scale=1 crashes target VM

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk15u-dev pull/58/head:pull/58
$ git checkout pull/58

Update a local copy of the PR:
$ git checkout pull/58
$ git pull https://git.openjdk.java.net/jdk15u-dev pull/58/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 58

View PR using the GUI difftool:
$ git pr show -t 58

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk15u-dev/pull/58.diff

[bridgekeeper]

👋 Welcome back evergizova! 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]

@kvergizova This change now passes all automated pre-integration checks.

After integration, the commit message for the final commit will be:

8251257: NMT: jcmd VM.native_memory scale=1 crashes target VM

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 2 new commits pushed to the master branch:

• fb53967: 8255908: ExceptionInInitializerError due to UncheckedIOException while initializing cgroupv1 subsystem
• 73ab669: 8249608: Vector register used by C2 compiled method corrupted at safepoint

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

[mlbridge]

Webrevs

• 00: Full (ed32fcb2)

[kvergizova]

/integrate

[openjdk]

@kvergizova Since your change was applied there have been 2 commits pushed to the master branch:

• fb53967: 8255908: ExceptionInInitializerError due to UncheckedIOException while initializing cgroupv1 subsystem
• 73ab669: 8249608: Vector register used by C2 compiled method corrupted at safepoint

Your commit was automatically rebased without conflicts.

Pushed as commit 723da96.

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