[PATCH v13 3/8] arm64: mte: Sync tags for pages where PTE is untagged

[Catalin Marinas]

On Mon, May 24, 2021 at 11:45:08AM +0100, Steven Price wrote:
> A KVM guest could store tags in a page even if the VMM hasn't mapped
> the page with PROT_MTE. So when restoring pages from swap we will
> need to check to see if there are any saved tags even if !pte_tagged().
> 
> However don't check pages for which pte_access_permitted() returns false
> as these will not have been swapped out.
> 
> Signed-off-by: Steven Price <steven.price at arm.com>

Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>