Re: [PATCH v9 1/3] xsm: create idle domain privileged and demote after setup

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

On Wed, Jun 29, 2022 at 10:21:08PM -0400, Daniel P. Smith wrote:
> There are new capabilities, dom0less and hyperlaunch, that introduce internal
> hypervisor logic, which needs to make resource allocation calls that are
> protected by XSM access checks. The need for these resource allocations are
> necessary for dom0less and hyperlaunch when they are constructing the initial
> domain(s).  This creates an issue as a subset of the hypervisor code is
> executed under a system domain, the idle domain, that is represented by a
> per-CPU non-privileged struct domain. To enable these new capabilities to
> function correctly but in a controlled manner, this commit changes the idle
> system domain to be created as a privileged domain under the default policy and
> demoted before transitioning to running. A new XSM hook,
> xsm_set_system_active(), is introduced to allow each XSM policy type to demote
> the idle domain appropriately for that policy type. In the case of SILO, it
> inherits the default policy's hook for xsm_set_system_active().
> 
> For flask, a stub is added to ensure that flask policy system will function
> correctly with this patch until flask is extended with support for starting the
> idle domain privileged and properly demoting it on the call to
> xsm_set_system_active().
> 
> Signed-off-by: Daniel P. Smith <dpsmith@apertussolutions.com>
> Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
> Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
> Acked-by: Julien Grall <jgrall@amazon.com> # arm
> Reviewed-by: Rahul Singh <rahul.singh@arm.com>
> Tested-by: Rahul Singh <rahul.singh@arm.com>

LGTM:

Acked-by: Roger Pau Monné <roger.pau@citrix.com>

Thanks, Roger.