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Date:   Thu, 11 Jul 2019 20:59:39 +0300
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Sean Christopherson <sean.j.christopherson@intel.com>
Cc:     "Xing, Cedric" <cedric.xing@intel.com>,
        linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org,
        akpm@linux-foundation.org, dave.hansen@intel.com,
        serge.ayoun@intel.com, shay.katz-zamir@intel.com,
        haitao.huang@intel.com, kai.svahn@intel.com, kai.huang@intel.com
Subject: Re: [RFC PATCH v2 0/3] An alternative __vdso_sgx_enter_enclave() to
 allow enclave/host parameter passing using untrusted stack
Message-ID: <20190711175939.abpj5hgcx5kjuh22@linux.intel.com>
References: <cover.1555965327.git.cedric.xing@intel.com>
 <20190424062623.4345-1-cedric.xing@intel.com>
 <20190710111719.nnoedfo4wvbfghq7@linux.intel.com>
 <686e47d2-f45c-6828-39d1-48374925de6c@intel.com>
 <20190710224628.epjxwlpqqxdurmzo@linux.intel.com>
 <20190710231538.dkc7tyeyvns53737@linux.intel.com>
 <27cf0fc7-71c6-7dc1-f031-86bf887f1fe1@intel.com>
 <20190711093809.4ogxe25laeoyp4ve@linux.intel.com>
 <20190711155037.GB15067@linux.intel.com>
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On Thu, Jul 11, 2019 at 08:50:37AM -0700, Sean Christopherson wrote:
> On Thu, Jul 11, 2019 at 12:38:09PM +0300, Jarkko Sakkinen wrote:
> > On Wed, Jul 10, 2019 at 04:37:41PM -0700, Xing, Cedric wrote:
> > > We are not judging which vessel is better (or the best) among all possible
> > > vessels. We are trying to enable more vessels. Every vessel has its pros and
> > > cons so there's *no* single best vessel.
> > 
> > I think reasonable metric is actually the coverage of the Intel SDK
> > based enclaves. How widely are they in the wild? If the user base is
> > large, it should be reasonable to support this just based on that.
> 
> Large enough that Andy agreed to take the vDSO code with the optional
> callback, despite his personal opinion being that mucking with uR{B,S}P
> from within the enclave is poor form.

OK, the cover letter empahasized things that did not make sense to me,
which made me to do my initial conclusions. I don't recall even reading
the word "coverage" from it.

Anyways, I'm sure we can land this after v21 has been published now that
the rationale is clear.

/Jarkko