On Fri, Sep 12, 2025 at 10:50:34AM -0400, Steven Sistare wrote: > > > > How to guarantee src/dst device topology match > > > > exactly the same with the new cmdline? > > > > > > That is up to the mgmt layer, to know how QEMU was originally started, and > > > what has been hot plugged afterwards. The fast qom-list-get command that > > > I recently added can help here. > > > > I see. If you think that is the best way to consume cpr-exec, would you > > add a small section into the doc patch for it as well? > > It is not related to cpr-exec. It is related to hot plug, for any migration > type scenario, so it does not fit in the cpr-exec docs.
IMHO it matters.. With cpr-transfer, QMP hot plugs works and will not contribute to downtime. cpr-exec also works, but will contribute to downtime. We could, in the comparison section between cpr-exec v.s. cpr-transfer, mention the potential difference on device hot plugs (out of many other differences), then also mention that there's an option to reduce downtime for cpr-exec due to hot-plug by converting QMP hot plugs into cmdlines leveraging qom-list-get and other facilities. From there we could further link to a special small section describing the usage of qom-list-get, or stop there. Thanks, -- Peter Xu
