Re: [PATCH v3 3/7] xen/arm: dom0less delay xenstore initialization

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Thu, 3 Apr 2025, Jason Andryuk wrote:
> To allocate the xenstore event channel and initialize the grant table
> entry, the xenstore domid is neeed.  A dom0 is created before the domUs,
> so it is normally available through hardware_domain.  With capabilities
> and dom0less, the xenstore domain may not be created first.
> 
> Keep the population of the page and HVM_PARAM_STORE_PFN in the normal
> domain construction, but delay event channel creation and grant seeding
> to after all domUs are created.  HVM_PARAM_STORE_PFN now serves as
> indication to setup xenstore since the device tree is no longer
> immediately available.  0 means no xenstore.  ~0ULL means legacy so only
> the event channel needs setup, and any other value means to seed the
> page.
> 
> dom0 needs to set xs_domid when it is serving as the xenstore domain.
> 
> The domain running xenstored needs to be the handler for VIRQ_DOM_EXC,
> so set that as well - it otherwise defaults to hardware domain.
> 
> Signed-off-by: Jason Andryuk <jason.andryuk@xxxxxxx>

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>