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Subject: Re: [PATCH v1 00/15] Add support for Nitro Enclaves
To:     "Paraschiv, Andra-Irina" <andraprs@amazon.com>,
        Alexander Graf <graf@amazon.com>, linux-kernel@vger.kernel.org
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        ne-devel-upstream@amazon.com
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <617eb49c-0ad9-8cf4-54bc-6d2cdfbb189a@redhat.com>
Date:   Mon, 27 Apr 2020 11:46:57 +0200
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On 27/04/20 11:22, Paraschiv, Andra-Irina wrote:
>>
>>
>> 1) having the kernel and initrd loaded by the parent VM in enclave
>> memory has the advantage that you save memory outside the enclave memory
>> for something that is only needed inside the enclave
> 
> Here you wanted to say disadvantage? :)Wrt saving memory, it's about
> additional memory from the parent / primary VM needed for handling the
> enclave image sections (such as the kernel, ramdisk) and setting the EIF
> at a certain offset in enclave memory?

No, it's an advantage.  If the parent VM can load everything in enclave
memory, it can read() into it directly.  It doesn't to waste its own
memory for a kernel and initrd, whose only reason to exist is to be
copied into enclave memory.

Paolo