8312620: WSL Linux build crashes after JDK-8310233

[tabata-d]

JDK-8312620 is a bug fix that addresses a regression in Linux hugepage detection introduced by JDK-8310233. On WSL1, the kernel reports a non‑zero Hugepagesize in /proc/meminfo but does not expose /sys/kernel/mm/hugepages, which causes the VM to hit an assertion in StaticHugePageSupport::scan_os() and crash when static hugepages are enabled (e.g., with -XX:+UseLargePages).

The fix was originally implemented in JDK 22. Now we are backporting this into JDK 11. It is a clean Backport.

This change touches the same code as JDK-8312394(#3172) , which addresses a regression introduced by JDK-8310233. Therefore, JDK-8312394 needs to be integrated before this fix.

Testing

System: Ran on Red Hat Enterprise Linux 9.4 (x86_64).
jtreg: A comprehensive jtreg run on the entire hotspot/jtreg test suite confirmed that all HotSpot tests passed.

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Progress

• JDK-8312620 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Integration blocker

 ⚠️ Dependency #3172 must be integrated first

Issue

• JDK-8312620: WSL Linux build crashes after JDK-8310233 (Bug - P3)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk11u-dev.git pull/3194/head:pull/3194
$ git checkout pull/3194

Update a local copy of the PR:
$ git checkout pull/3194
$ git pull https://git.openjdk.org/jdk11u-dev.git pull/3194/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 3194

View PR using the GUI difftool:
$ git pr show -t 3194

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk11u-dev/pull/3194.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back dtabata! A progress list of the required criteria for merging this PR into pr/3172 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 change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (58421466)

[tabata-d]

After the discussion in #3210, I have decided to close this PR.