Re: [PATCH 03/16] KVM: arm64: Turn kvm_pgtable_stage2_set_owner into kvm_pgtable_stage2_annotate

[Quentin Perret]

On Thursday 15 Jul 2021 at 17:31:46 (+0100), Marc Zyngier wrote:
> @@ -815,7 +807,7 @@ int kvm_pgtable_stage2_set_owner(struct kvm_pgtable *pgt, u64 addr, u64 size,
>  		.arg		= &map_data,
>  	};
>  
> -	if (owner_id > KVM_MAX_OWNER_ID)
> +	if (!annotation || (annotation & PTE_VALID))
>  		return -EINVAL;

Why do you consider annotation==0 invalid? The assumption so far has
been that the owner_id for the host is 0, so annotating a range with 0s
should be a valid operation -- this will be required when e.g.
transferring ownership of a page back to the host.

>  
>  	ret = kvm_pgtable_walk(pgt, addr, size, &walker);
> -- 
> 2.30.2
>