Re: [PATCH v14 7/8] KVM: arm64: ioctl to fetch/store tags in a guest

From: Catalin Marinas
Date: Mon Jun 07 2021 - 13:21:10 EST


On Mon, Jun 07, 2021 at 12:08:15PM +0100, Steven Price wrote:
> The VMM may not wish to have it's own mapping of guest memory mapped
> with PROT_MTE because this causes problems if the VMM has tag checking
> enabled (the guest controls the tags in physical RAM and it's unlikely
> the tags are correct for the VMM).
>
> Instead add a new ioctl which allows the VMM to easily read/write the
> tags from guest memory, allowing the VMM's mapping to be non-PROT_MTE
> while the VMM can still read/write the tags for the purpose of
> migration.
>
> Signed-off-by: Steven Price <steven.price@xxxxxxx>

Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>