Re: [Qemu-devel] [RFC PATCH v2 06/16] sev: add Secure Encrypted Virtulization (SEV) support

[Paolo Bonzini]

On 22/09/2016 16:52, Brijesh Singh wrote:
>   to launch unencrypted SEV guest:
>  # $QEMU \
>     -object sev-launch-info,id=launch0,flags.ks=off \
>     -object sev-guest-info,id,sev0,launch=launch0 \
>     -object security-policy,id=secure0,memory-encryption=sev0 \
>     -machine ....,security-policy=secure0
> 
> - sev-receive-info: provides the properties to set/get parameters required
>   to launch encrypted SEV guest.
> 
>   In this mode the boot images received from the guest owner are
>   pre-encrypted with owners transport keys. The SEV guest boot process
>   would re-encrypt the images using guest owner's key.
> 
>   to launch encrypted SEV guest:
> 
>  # $QEMU \
>     -object sev-receive-info,id=launch0,flags.ks=off \
>     -object sev-guest-info,id=sev0,launch=launch0 \
>     -object security-policy,id=secure0,memory-encryption=sev0 \
>     -machine ....,security-policy=secure0
> 
> - sev-policy-info: provides properties to get/set SEV specific policy
>   parameters required by SEV launch and migrate objects.
> 
>   e.g to disable key share during encrypted launch.
>   # $QEMU \
>     -object sev-policy-info,id=policy0,ks=off \
>     -object sev-launch-info,id=sev0,policy=policy0 \
>     .....
> 
>    sev-policy should be provided by the guest owner.
> 
> - sev-guest-info: provides properties to set SEV guest launch object id
>   used during guest launch.
> 
>   to use encrypted guest launch
>   # $QEMU \
>      -object sev-receive-info,id=launch0 \
>      -object sev-send-info,id=send0 \
>      -object sev-guest-info,id=sev0,launch=launch0,send=send0 \
>      .....
> 

References to other objects should be implemented as link properties
(e.g. with type 'link<sev-guest-info>').  Then QOM takes care of filling
in a QSEVGuestInfo* with the pointer to an object with the right id.

There is some redundancy (e.g. "flags.ks" in launch/receive vs. "ks" in
policy).  Can you document the full model in
docs/amd-memory-encryption.txt?  It's not necessary to include the
kernel API documentation.

Paolo