Sebastien Boeuf a887d87c2a vm-migration: Add PageFault command for postcopy and on demand restore ...

Introducing PageFault as the new wire command needed by both postcopy
live migration and on demand restore from the offload daemon. This new
command describes the need from the destination to fault the page
content in. This request describes the page through a MemoryRange
structure, and the response can be either 0 or the actual page size.

In case it is 0, that means the source had access to the guest memory
and was able to copy the page content directly. In case the response is
the actual page size, there is a payload associated which contains the
page content.

We can expect local live migration and offload restore to run locally
and therefore have access to the guest memory. The remote live migration
over the network is the case where we would expect the page content to
be sent over the wire.

This command is served through an additional connection happening on the
UNIX or TCP socket. The goal is to keep the same codepath between local
and remote migrations. This additional channel allows PageFault commands
to be issued asynchronously so they can be served without blocking the
main connection.

A connection role is introduced in order to identify an additional
connection related to pre-copy memory versus the newly introduced
channel for serving post-copy requests.

Signed-off-by: Sebastien Boeuf <sboeuf@meta.com>
Assisted-by: Claude:claude-opus-4-7

2026-06-24 12:51:40 +00:00

..

src

vm-migration: Add PageFault command for postcopy and on demand restore

2026-06-24 12:51:40 +00:00

Cargo.toml

vm-migration: client-side of a TLS connection

2026-06-12 10:11:56 +00:00