Re: [PATCH 1/2] docs/designs/launch: hyperlaunch design document

["Roger Pau Monné" <roger.pau@citrix.com>]

Just took a quick look at it.

On Mon, Mar 15, 2021 at 11:18:13PM -0400, Daniel P. Smith wrote:
> + +---------------+-----------+------------+-----------+-------------+---------------------+
> + | **Xen Dom0**  | **Linux** | **Late**   | **Jail**  | **Xen**     | **Xen Hyperlaunch** |
> + | **(Classic)** | **KVM**   | **HW Dom** | **house** | **dom0less**+---------+-----------+
> + |               |           |            |           |             | Static  | Dynamic   |
> + +===============+===========+============+===========+=============+=========+===========+
> + | Hypervisor able to launch multiple VMs during host boot                                |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |     Y     |       Y     |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Hypervisor supports Static Partitioning                                                |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |     Y     |       Y     |    Y    |           |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Able to launch VMs dynamically after host boot                                         |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |       Y       |     Y     |      Y*    |     Y     |       Y*    |         |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Supports strong isolation between all VMs started at host boot                         |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |     Y     |       Y     |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Enables flexible sequencing of VM start during host boot                               |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |             |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Prevent all-powerful static root domain being launched at boot                         |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |       Y*    |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Operates without a Highly-privileged management VM (eg. Dom0)                          |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |      Y*    |           |       Y*    |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Operates without a privileged toolstack VM (Control Domain)                            |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |       Y*    |    Y    |           |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Extensible VM configuration applied before launch of VMs at host boot                  |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |             |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Flexible granular assignment of permissions and functions to VMs                       |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |             |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | Supports extensible VM measurement architecture for DRTM and attestation               |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |             |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + | PCI passthrough configured at host boot                                                |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+
> + |               |           |            |           |             |    Y    |     Y     |
> + +---------------+-----------+------------+-----------+-------------+---------+-----------+

I'm curious about this, I assume this is done using vPCI so that
there's no hardware domain (and user-space device model) involved for
PCI passthrough?

I'm also not sure how you are going to handle things like SR-IOV
devices. Right now SR-IOV capability is setup and initialized by the
hardware domain, and the new virtual devices are notified to Xen once
setup is done. Do you plan to move those bits into Xen, so that it can
setup and initialize the SR-IOV capability?

Thanks, Roger.