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To:     Jarkko Sakkinen <jarkko@kernel.org>, linux-sgx@vger.kernel.org
Cc:     Reinette Chatre <reinette.chatre@intel.com>,
        Nathaniel McCallum <nathaniel@profian.com>,
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        <linux-kernel@vger.kernel.org>
References: <20220304122852.563475-1-jarkko@kernel.org>
From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: [PATCH RFC] x86: Add SGX_IOC_ENCLAVE_AUGMENT_PAGES
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On 3/4/22 04:28, Jarkko Sakkinen wrote:
> Explicit EAUG ioctl is a better choice than an implicit EAUG from a page
> fault handler because it allows to have O(1) number of kernel-enclave round
> trips for EAUG-EACCEPT{COPY} process, instead of O(n), as it is in the case
> when a page fault handler EAUG single page at a time.

So this is basically an optimization?  It's MADV_WILLNEED or
MAP_POPULATE to the cost of avoid future faults?