Re: [RFC PATCH 00/23] KVM SGX virtualization support

Kai Huang
2021-01-15T14:44:21Z

On Tue, 2021-01-12 at 15:07 +1300, Kai Huang wrote:
> > > > >
> > > > > To support virtual EPC, add a new misc device /dev/sgx_virt_epc to SGX
> > > > > core/driver to allow userspace (Qemu) to allocate "raw" EPC, and use it as
> > > > > "virtual EPC" for guest. Obviously, unlike EPC allocated for host SGX
> > > > > driver,
> > > > > virtual EPC allocated via /dev/sgx_virt_epc doesn't have enclave
> > > > > associated,
> > > > > and how virtual EPC is used by guest is compeletely controlled by guest's
> > > > > SGX
> > > > > software.
> > > >
> > > > I think that /dev/sgx_vepc would be a clear enough name for the device. This
> > > > text has now a bit confusing "terminology" related to this.
> > >
> > > /dev/sgx_virt_epc may be clearer from userspace's perspective, for instance,
> > > if people see /dev/sgx_vepc, they may have to think about what it is,
> > > while /dev/sgx_virt_epc they may not.
> > >
> > > But I don't have strong objection here. Does anyone has anything to say here?
> >
> > It's already an abberevation to start with, why leave it halfways?
> >
> > Especially when three remaining words have been shrunk to single
> > characters ('E', 'P' and 'C').
> >
>
> I have expressed my opinion above. And as I said I don't have strong objection
> here. I'll change to /dev/sgx_vepc if no one opposes.

Hi Jarkko,

I am reluctant to change to /dev/sgx_vepc now, because there are lots of
'sgx_virt_epc' in the code. For instance, 'struct sgx_virt_epc', and function names
in sgx/virt.c are all sgx_virt_epc_xxx(), which has 'sgx_virt_epc' as prefix. I feel
changing to /dev/sgx_vepc only is kinda incomplete, but I really don't want to change
so many 'sgx_virt_epc' to 'sgx_vepc'.

(Plus I still think 'virt_epc' is more obvious than 'vepc' from userspace's
perspective.)

Does it make sense?