On 22/08/2024 04:32, Aneesh Kumar K.V wrote:
> Steven Price <steven.price@xxxxxxx> writes:
>
>> At runtime if the realm guest accesses memory which hasn't yet been
>> mapped then KVM needs to either populate the region or fault the guest.
>>
>> For memory in the lower (protected) region of IPA a fresh page is
>> provided to the RMM which will zero the contents. For memory in the
>> upper (shared) region of IPA, the memory from the memslot is mapped
>> into the realm VM non secure.
>>
>> Signed-off-by: Steven Price <steven.price@xxxxxxx>
>> ---
>> Changes since v2:
>> * Avoid leaking memory if failing to map it in the realm.
>> * Correctly mask RTT based on LPA2 flag (see rtt_get_phys()).
>> * Adapt to changes in previous patches.
>>
>
> ....
>
>> - gfn = ipa >> PAGE_SHIFT;
>> + gfn = (ipa & ~gpa_stolen_mask) >> PAGE_SHIFT;
>> memslot = gfn_to_memslot(vcpu->kvm, gfn);
>> +
>> + if (kvm_slot_can_be_private(memslot)) {
>> + ret = private_memslot_fault(vcpu, fault_ipa, memslot);
>> + if (ret != -EAGAIN)
>> + goto out;
>> + }
>>
>
> Shouldn't this be s/fault_ipa/ipa ?
Well they should both be the same unless we're in some scary parallel
universe where we have nested virtualisation *and* realms at the same
time (shudder!). But yes "ipa" would be more consistent so I'll change it!
Steve
> ret = private_memslot_fault(vcpu, ipa, memslot);
>
> -aneesh
