Re: [PATCH v6 1/4] kvm: arm64: introduce new flag for non-cacheable IO memory
From: Ankit Agrawal
Date: Fri Feb 09 2024 - 09:12:00 EST
>> + default:
>> + WARN_ON_ONCE(1);
>
> Return -EINVAL?
Sure.
>> > + case KVM_PGTABLE_PROT_NORMAL_NC:
>> > + attr = KVM_S2_MEMATTR(pgt, NORMAL_NC);
>> > + break;
>>
>> Does it make sense to allow executable here as well? I don't think it's
>> harmful but not sure there's a use-case for it either.
>
> Ah, we should just return EINVAL for that too.
>
> I get that the memory attribute itself is not problematic, but since
> we're only using this thing for MMIO it'd be a rather massive
> bug in KVM... We reject attempts to do this earlier in user_mem_abort().
Ack, will change to test executable and return -EINVAL in that case.