Re: [PATCH v20 09/15] qapi: add local migration parameter

On Wed, Jul 29, 2026 at 12:12:47PM +0300, Vladimir Sementsov-Ogievskiy wrote:
> We are going to implement local-migration feature: some devices will be
> able to transfer open file descriptors through migration stream (which
> must UNIX domain socket for that purpose).  This allows to transfer the
> whole backend state without reconnecting and restarting the backend
> service. For example, virtio-net will migrate its attached TAP netdev,
> together with its connected file descriptors.
> 
> In this commit we introduce a migration parameter, which enables
> the feature for devices that support it (none at the moment).
> 
> We can't simply auto-detect local migration by checking whether the
> migration channel is a UNIX domain socket: the UNIX socket may be only
> the first part of the transfer channel to a remote target.  Hence an
> explicit parameter is needed. More over, "local" migration parameter
> may be useful in cpr-exec mode, when FDs are passed through exec
> instead of UNIX socket.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <[email protected]>

Reviewed-by: Peter Xu <[email protected]>

-- 
Peter Xu