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Date:   Mon, 14 Mar 2022 05:45:45 +0200
From:   Jarkko Sakkinen <jarkko@kernel.org>
To:     Reinette Chatre <reinette.chatre@intel.com>
Cc:     Haitao Huang <haitao.huang@linux.intel.com>,
        "Dhanraj, Vijay" <vijay.dhanraj@intel.com>,
        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "bp@alien8.de" <bp@alien8.de>,
        "Lutomirski, Andy" <luto@kernel.org>,
        "mingo@redhat.com" <mingo@redhat.com>,
        "linux-sgx@vger.kernel.org" <linux-sgx@vger.kernel.org>,
        "x86@kernel.org" <x86@kernel.org>,
        "Christopherson,, Sean" <seanjc@google.com>,
        "Huang, Kai" <kai.huang@intel.com>,
        "Zhang, Cathy" <cathy.zhang@intel.com>,
        "Xing, Cedric" <cedric.xing@intel.com>,
        "Huang, Haitao" <haitao.huang@intel.com>,
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Subject: Re: [PATCH V2 16/32] x86/sgx: Support restricting of enclave page
 permissions
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On Mon, Mar 14, 2022 at 05:42:43AM +0200, Jarkko Sakkinen wrote:
> On Fri, Mar 11, 2022 at 11:28:27AM -0800, Reinette Chatre wrote:
> > Supporting permission restriction in an ioctl() enables the runtime to manage
> > the enclave memory without needing to map it.
> 
> Which is opposite what you do in EAUG. You can also augment pages without
> needing the map them. Sure you get that capability, but it is quite useless
> in practice.

Essentially you are tuning for a niche artifical use case over the common
case that most people end up doing. It makes no sense.

BR, Jarkko