[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [XEN PATCH 1/7] xen: introduce XENFEAT_xenstore_late_init





On 10/01/2022 22:55, Stefano Stabellini wrote:

I have a patch for Linux that if XENFEAT_xenstore_late_init is present
makes Linux wait for an event notification before initializing xenstore:
https://marc.info/?l=xen-devel&m=164160299315589

So with v1 of the Xen and Linux patches series:
- Xen allocates the event channel at domain creation
- Linux boots, sees XENFEAT_xenstore_late_init and wait for an event
- init-dom0less later allocates the xenstore page
- init-dom0less triggers the xenstore event channel
- Linux receives the event and finishes the initialization, including
   mapping the xenstore page

You can get this behaviour without the new feature.

- Xen allocates the event channel at domain creation
- Linux boots, sees HVM_PARAM_STORE_PFN is invalid and there's a xenstore event channel and waits for an event
- init-dom0less later allocates the xenstore page
- init-dom0less triggers the xenstore event channel
- Linux receives the event and finishes the initialization, including
   mapping the xenstore page-

David



 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.