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From: Laszlo Ersek <lersek@redhat.com>
Message-ID: <57ffda5b-564c-a106-0f1e-a42485da55ef@redhat.com>
Date: Fri, 8 Sep 2017 18:11:42 +0200
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Subject: Re: [Qemu-devel] libvirt/QEMU/SEV interaction
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To: "Daniel P. Berrange" <berrange@redhat.com>, Brijesh Singh <brijesh.singh@amd.com>
Cc: "libvir-list@redhat.com" <libvir-list@redhat.com>, "Lendacky, Thomas" <Thomas.Lendacky@amd.com>, "Relph, Richard" <Richard.Relph@amd.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

On 09/08/17 17:51, Daniel P. Berrange wrote:
> On Fri, Sep 08, 2017 at 10:48:10AM -0500, Brijesh Singh wrote:

>> I am looking at [1] to get the feel for how do we model it in the XML.
>> As you can see I am using ad-hoc <qemu:args> to create the sev-guest
>> object. Currently, sev-guest object accepts the following properties:
>>
>> dh-cert-file: <file containing the GO DH key>
>> session-info-file: <file contain the GO session info>
>> policy: <int32 GO policy>
>>
>> I believe the new XML model will influence the property input type,
>> Any recommendation on how do model this part ? thank you so much.
> 
> That looks ok to me - even if QEMU wants the data provided in
> files on disk, libvirt can just create the files on the fly
> from the data it has in the <sev> element in the XML file.
> Since they're only needed during startup, libvirt can then
> easily delete the files the moment QEMU has completed its
> startup.

/dev/fd/N filenames could be used for poor man's fd passing, I think.

(/dev/fd is a symlink to the /proc/self/fd directory)

proc(5) has documentation on this.

Thanks,
Laszlo