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Date:   Sat, 15 Feb 2020 09:35:19 +0200
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Jethro Beekman <jethro@fortanix.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        linux-sgx@vger.kernel.org, akpm@linux-foundation.org,
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        linux-security-module@vger.kernel.org,
        Suresh Siddha <suresh.b.siddha@intel.com>,
        Haitao Huang <haitao.huang@linux.intel.com>
Subject: Re: [PATCH v26 10/22] x86/sgx: Linux Enclave Driver
Message-ID: <20200215073519.GE9958@linux.intel.com>
References: <20200209212609.7928-1-jarkko.sakkinen@linux.intel.com>
 <20200209212609.7928-11-jarkko.sakkinen@linux.intel.com>
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On Sat, Feb 15, 2020 at 09:32:34AM +0200, Jarkko Sakkinen wrote:
> On Thu, Feb 13, 2020 at 02:59:52PM +0100, Jethro Beekman wrote:
> > Besides only partially measuring a page, there are some other fringe
> > cases that are technically possible, although I haven't seen any
> > toolchains that do that. These include not interleaving EADD and
> > EEXTEND, not using logical ordering for the EEXTENDs, and call EEXTEND
> > multiple times on the same chunk. Maximum interoperability would
> > require supporting any EADD/EEXTEND sequence.
> 
> The reason why EEXTEND deals with chunks is nothing to do with the
> granularity but just to amortize the algorithm. I did ask about this
> and this is the answer that I got.

I mean asked from people who have been involed in the development of
this CPU feature.

/Jarkko