Re: [libvirt] [PATCH 3/4] conf: introduce sev element in domain

On Mon, Feb 26, 2018 at 11:53:35AM -0600, Brijesh Singh wrote: > Secure Encrypted Virtualization (sev) element is used to provide the guest > owners input parameters used for creating an encrypted VM using AMD SEV > feature. SEV feature supports running encrypted VM under the control of > KVM. Encrypted VMs have their pages (code and data) secured such that only > the guest itself has access to the unencrypted version. Each encrypted VM > is associated with a unique encryption key; if its data is accessed to a > different entity using a different key the encrypted guests data will be > incorrectly decrypted, leading to unintelligible data. > > QEMU >= 2.12 provides 'sev-guest' object which supports launching encrypted > VMs. A typical command line > > # $QEMU ... \ > -machine memory-encryption=sev0 \ > -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ > ... > > Signed-off-by: Brijesh Singh <brijesh.singh(a)amd.com&gt; > --- > docs/formatdomain.html.in | 71 +++++++++++++++++++++++++++++++++++++++++++ > src/conf/domain_conf.c | 64 +++++++++++++++++++++++++++++++++++++++ > src/conf/domain_conf.h | 18 +++++++++++ > src/qemu/qemu_command.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 230 insertions(+) In general we'd expect to see additions to the test suite for any XML changes. eg a qemuxml2xmltest and qemuxml2argvtest addition.

> > diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in > index 6fd2189cd2f4..d18e3fb1d976 100644 > --- a/docs/formatdomain.html.in > +++ b/docs/formatdomain.html.in > @@ -8195,6 +8195,77 @@ qemu-kvm -net nic,model=? /dev/null > > <p>Note: DEA/TDEA is synonymous with DES/TDES.</p> > > + <h3><a id="sev">Secure Encrypted Virtualization (SEV)</a></h3> > + > + <p> > + The contents of the <code>sev</code> element is used to provide the > + guest owners input used for creating an encrypted VM using the AMD > + Secure Encrypted Virtualization (SEV) feature. > + > + SEV is an extension to the AMD-V architecture which supports running > + encrypted virtual machine (VMs) under the control of KVM. Encrypted > + VMs have their pages (code and data) secured such that only the guest > + itself has access to the unencrypted version. Each encrypted VM is > + associated with a unique encryption key; if its data is accessed to a > + different entity using a different key the encrypted guests data will > + be incorrectly decrypted, leading to unintelligible data. > + </p> > + <pre> > +&lt;domain&gt; > + ... > + &lt;sev&gt; > + &lt;policy&gt; 1 &lt;/policy&gt; > + &lt;cbitpos&gt; 47 &lt;/cbitpos&gt; > + &lt;reduced-phys-bits&gt; 5 &lt;/reduced-phys-bits&gt; > + &lt;session&gt; ... &lt;/session&gt; > + &lt;dh-cert&gt; ... &lt;/dh&gt; > + &lt;/sev&gt; Minor nitpick - since this inheranted SEV specific, I think we could do with having a generic top level element with a type=sev. eg <launch-security type="sev"> <policy>...</policy> <cbitpos>..</cbitpos> ...etc... </launch> then we can plug in custom data if other vendors invent competing solutions to AMD's SEV.