Re: [RFC 03/16] KVM: selftests: handle encryption bits in page tables

[Paolo Bonzini]

On 06/10/21 01:44, Michael Roth wrote:
> SEV guests rely on an encyption bit which resides within the range that
> current code treats as address bits. Guest code will expect these bits
> to be set appropriately in their page tables, whereas helpers like
> addr_gpa2hva() will expect these bits to be masked away prior to
> translation. Add proper handling for these cases.

This is not what you're doing below in addr_gpa2hva, though---or did I 
misunderstand?

I may be wrong due to not actually having written the code, but I'd 
prefer if most of these APIs worked only if the C bit has already been 
stripped.  In general it's quite unlikely for host code to deal with C=1 
pages, so it's worth pointing out explicitly the cases where it does.

Paolo

> @@ -1460,9 +1480,10 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
>    * address providing the memory to the vm physical address is returned.
>    * A TEST_ASSERT failure occurs if no region containing gpa exists.
>    */
> -void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa)
> +void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa_raw)
>   {
>   	struct userspace_mem_region *region;