Fix CPUFeatures crash on new->old CPU

[jankratochvil]

• reproducible on i7-1165G7 "qemu-kvm -cpu host" for a checkpoint and "qemu-kvm -cpu SandyBridge" for its restore

---

Progress

• Change must not contain extraneous whitespace

Reviewers

• Radim Vansa (@rvansa - Committer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/crac.git pull/134/head:pull/134
$ git checkout pull/134

Update a local copy of the PR:
$ git checkout pull/134
$ git pull https://git.openjdk.org/crac.git pull/134/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 134

View PR using the GUI difftool:
$ git pr show -t 134

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/crac/pull/134.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back jkratochvil! A progress list of the required criteria for merging this PR into crac will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@jankratochvil This change is no longer ready for integration - check the PR body for details.

[mlbridge]

Webrevs

• 04: Full - Incremental (c1983089)
• 03: Full - Incremental (1b24fed5)
• 02: Full - Incremental (f66a71ae)
• 01: Full - Incremental (f9470978)
• 00: Full (d26f972a)

[bridgekeeper]

@jankratochvil This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[bridgekeeper]

@jankratochvil This pull request has been inactive for more than 8 weeks and will now be automatically closed. If you would like to continue working on this pull request in the future, feel free to reopen it! This can be done using the /open pull request command.

[jankratochvil]

/open

[openjdk]

@jankratochvil This pull request is now open

[bridgekeeper]

@jankratochvil This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[bridgekeeper]

@jankratochvil This pull request has been inactive for more than 8 weeks and will now be automatically closed. If you would like to continue working on this pull request in the future, feel free to reopen it! This can be done using the /open pull request command.

[jankratochvil]

/open

[openjdk]

@jankratochvil This pull request is now open

[bridgekeeper]

@jankratochvil This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[rvansa]

Sorry for keeping this waiting for a long time. In the past I wasn't sure about using /tmp/ rather than shm_open target but since os::get_temp_directory() has this part hard-coded, too, I think it's acceptable to use that one.

I would prefer crac_restore_finalize to use an enum rather than a char but otherwise this looks good - and if it fixes some usecase, let's integrate it.

[jankratochvil]

@rvansa Sorry for the review but we have been last week talking with @AntonKozlov I should rather do the full rework (move the CPUFeatures protection to the parent JDK before the JDK is restored) than this fix-up.

[bridgekeeper]

@jankratochvil This pull request has been inactive for more than 8 weeks and will be automatically closed if another 8 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!