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Date:   Thu, 20 Dec 2018 15:12:13 +0200
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Sean Christopherson <sean.j.christopherson@intel.com>,
        Jethro Beekman <jethro@fortanix.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "x86@kernel.org" <x86@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-sgx@vger.kernel.org" <linux-sgx@vger.kernel.org>,
        Josh Triplett <josh@joshtriplett.org>,
        Haitao Huang <haitao.huang@linux.intel.com>,
        "Dr . Greg Wettstein" <greg@enjellic.com>
Subject: Re: x86/sgx: uapi change proposal
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On Thu, Dec 20, 2018 at 12:32:04PM +0200, Jarkko Sakkinen wrote:
> On Wed, Dec 19, 2018 at 06:58:48PM -0800, Andy Lutomirski wrote:
> > Can one of you explain why SGX_ENCLAVE_CREATE is better than just
> > opening a new instance of /dev/sgx for each encalve?
> 
> I think that fits better to the SCM_RIGHTS scenario i.e. you could send
> the enclav to a process that does not have necessarily have rights to
> /dev/sgx. Gives more robust environment to configure SGX.

My only open for the implementation is where to swap? If it is a VMA,
whose VMA?

Please share your views here. Not a blocker for me to work on the
implementation, though. I'll use a private shmem file up until there
is a better option.

This ioctl API discussion is kind of meaningless for me ATM because it
does not have that much effect to the internals even if it wouldn't be
perfect in v19. Very trival to change.

/Jarkko