OvmfPkg/CpuHotplugSmm: delay SMM exit #6138
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Let APs wait until the BSP has completed the register updates to remove the CPU. This makes sure all APs stay in SMM mode until the CPU hot-unplug operation is complete, which in turn makes sure the ACPI lock is released only after the CPU hot-unplug operation is complete. Some background: The CPU hotplug SMI is triggered from an ACPI function which is protected by an ACPI lock. The ACPI function is in the ACPI tables generated by qemu. Signed-off-by: Gerd Hoffmann <[email protected]>
tianocore-assign-reviewers
bot
requested review from
ardbiesheuvel and
jyao1
ardbiesheuvel
approved these changes
Sep 13, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Let APs wait until the BSP has completed the register updates to remove
the CPU. This makes sure all APs stay in SMM mode until the CPU
hot-unplug operation is complete, which in turn makes sure the ACPI lock
is released only after the CPU hot-unplug operation is complete.
Some background: The CPU hotplug SMI is triggered from an ACPI function
which is protected by an ACPI lock. The ACPI function is in the ACPI
tables generated by qemu.
Signed-off-by: Gerd Hoffmann [email protected]