Re: [RFC PATCH v2 22/69] KVM: x86: Add vm_type to differentiate legacy VMs from protected VMs

[Xiaoyao Li]

On 11/11/2021 3:28 PM, Paolo Bonzini wrote:
> On 11/11/21 04:28, Xiaoyao Li wrote:
> > > Heh, because kvm_dev_ioctl_create_vm() takes an "unsigned long" for 
> > > the type and
> > > it felt wrong to store it as something else.  Storing it as a smaller 
> > > field should
> > > be fine, I highly doubt we'll get to 256 types anytime soon :-)
> >
> > It's the bit position. We can get only 8 types with u8 actually.
>
> Every architecture defines the meaning, and for x86 we can say it's not 
> a bit position.

Sorry, I find I was wrong. The types are not bit position but value.

KVM_CAP_VM_TYPES reports the supported vm types using bitmap that bit n 
represents type value n.

> Paolo