From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Subject: Re: [PATCH v17 18/23] platform/x86: Intel SGX driver
Date: Wed, 19 Dec 2018 07:00:47 +0200
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To: Sean Christopherson <sean.j.christopherson@intel.com>
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On Tue, Dec 18, 2018 at 10:53:49AM -0800, Sean Christopherson wrote:
> What if we re-organize the ioctls in such a way that we leave open the
> possibility of allocating raw EPC for KVM via /dev/sgx?  I'm not 100%
> positive this approach will work[1], but conceptually it fits well with
> KVM's memory model, e.g. KVM is aware of the GPA<->HVA association but
> generally speaking doesn't know what's physically backing each memory
> region.

Why would you want to pass EPC through user space to KVM rather than
KVM allocating it through kernel interfaces?

> Tangentially related, I think we should support allocating multiple
> enclaves from a single /dev/sgx fd, i.e. a process shouldn't have to
> open /dev/sgx every time it wants to create a new enclave.

I'm fine with this. It just requires to create anon inode. I'll just
add a new field called 'enclave_fd' to struct sgx_enclave_create and
that's all.

I think I have otherwise ingredients for v19 ready except where to swap.

/Jarkko