Advertise `VIRTIO_NET_F_GUEST_ANNOUNCE` on virtio-net devices, surface
`VIRTIO_NET_S_ANNOUNCE` through config status, and handle
`VIRTIO_NET_CTRL_ANNOUNCE_ACK` on the control queue.
This adds the guest-visible state needed for post-migration or
post-restore announce requests; the VMM side triggering is added in
follow-up commits.
The motivation is to reduce post-migration and post-restore
connectivity gap. After a live migration or after restoring, it can
take the guest several seconds to be reachable again over the network.
With these announcements, the network path should be refreshed within a
few milliseconds.
On-behalf-of: SAP sebastian.eydam@sap.com
Signed-off-by: Sebastian Eydam <sebastian.eydam@cyberus-technology.de>
Wire up the source side of postcopy migration over TCP. When
`mode=postcopy` is requested on vm.send-migration, the source skips
the pre-copy dirty-tracking loop and lets the destination resume early,
then serves guest pages on demand over a dedicated connection.
Signed-off-by: Sebastien Boeuf <sboeuf@meta.com>
Assisted-by: Claude:claude-opus-4-7
Document how live migration protocol versions are handled, including
the supported current/previous version window and the need to migrate
through an intermediate Cloud Hypervisor version for larger version
gaps.
On-behalf-of: SAP leander.kohler@sap.com
Signed-off-by: Leander Kohler <leander.kohler@cyberus-technology.de>
Minor modifications were made to make the sentences sound more natural.
Also fixed some parameter usage issues in bash code block.
Signed-off-by: Yi Wang <foxywang@tencent.com>
Updated the live migration documentation to include instructions for
performing cross-host live migrations over TCP connections.
Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
The previous docs were very developer centric and have led several
people to believe that cross-machine migration is not supported at
all.
Signed-off-by: Julian Stecklina <julian.stecklina@cyberus-technology.de>
I've added newlines between paragraphs and code blocks for easier
reading. I've also changed the code blocks to use the correct
highlighting.
Signed-off-by: Julian Stecklina <julian.stecklina@cyberus-technology.de>
To enable live-migration for vhost-user devices, we now always shutdown
the source VM when the migration is completed. This patch reflects this
change in the documentation.
Signed-off-by: Bo Chen <chen.bo@intel.com>
