Date: Wed, 13 Sep 2017 23:07:34 +0200
From: Borislav Petkov <bp@suse.de>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>, Joerg Roedel <joro@8bytes.org>,
        "Michael S . Tsirkin" <mst@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        =?utf-8?B?XCJSYWRpbSBLcsSNbcOhxZlcIg==?= <rkrcmar@redhat.com>,
        Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: [RFC Part2 PATCH v3 16/26] KVM: SVM: Add support for SEV
 LAUNCH_UPDATE_DATA command
Message-ID: <20170913210734.grfwb26rwudgbm2s@pd.tnic>
References: <20170724200303.12197-1-brijesh.singh@amd.com>
 <20170724200303.12197-17-brijesh.singh@amd.com>
 <20170913175537.wlfk3tmipx3xtbun@pd.tnic>
 <6f38ed16-376e-6716-981e-20bdf31c58b3@amd.com>
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On Wed, Sep 13, 2017 at 02:45:37PM -0500, Brijesh Singh wrote:
> Actually I don't know what should be sane upper bound in this case --
> typically we encrypt the guest BIOS using LAUNCH_UPDATE_DATA command.
> I have heard that some user may want to create a pre-encrypted image
> (which may contains guest BIOS + kernel + initrd) -- this can be huge.
> 
> For SEV guest, we have been needing to pin the memory hence how about if
> we limit the number of pages to pin with rlimit ? The rlimit check can
> also include the guest RAM pinning.

rlimit sounds like a sensible thing to do. It would be interesting to
hear what the general policy is wrt guest sizes that KVM folk do ...

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--