Zhang Chen <[email protected]> writes: > On Fri, Jan 16, 2026 at 2:26 PM Markus Armbruster <[email protected]> wrote: >> >> Lukas Straub <[email protected]> writes: >> >> > On Wed, 14 Jan 2026 15:11:55 -0500 >> > Peter Xu <[email protected]> wrote: >> > >> >> On Wed, Jan 14, 2026 at 02:56:57PM -0500, Peter Xu wrote: >> >> > COLO was broken for QEMU release 10.0/10.1 without anyone noticed. One >> >> > reason might be that we don't have an unit test for COLO (which we >> >> > explicitly require now for any new migration feature). The other reason >> >> > should be that there are just no more active COLO users, at least based >> >> > on >> >> > the latest development of QEMU. >> >> > >> >> > I don't remember seeing anything really active in the past few years in >> >> > COLO development. >> >> > >> >> > Meanwhile, COLO migration framework maintainer (Hailiang Zhang)'s last >> >> > email to qemu-devel is in Dec 2021 where the patch proposed an email >> >> > change (<[email protected]>). >> >> > >> >> > We've discussed this for a while, see latest discussions here (our >> >> > thoughts >> >> > of deprecating COLO framework might be earlier than that, but still): >> >> > >> >> > https://lore.kernel.org/r/[email protected]/ >> >> > https://lore.kernel.org/r/[email protected] >> >> > >> >> > Let's make it partly official and put COLO into deprecation list. If >> >> > anyone cares about COLO and is deploying it, please send an email to >> >> > qemu-devel to discuss. >> >> > >> >> > Otherwise, let's try to save some energy for either maintainers or >> >> > developers who is looking after QEMU. Let's save the work if we don't >> >> > even >> >> > know what the work is for. >> >> > >> >> > Cc: Lukáš Doktor <[email protected]> >> >> >> >> My apologize, I copied the wrong email. >> >> >> >> Cc: Lukas Straub <[email protected]> >> > >> > Nack. >> > >> > This code has users, as explained in my other email: >> > https://lore.kernel.org/qemu-devel/20260115224516.7f0309ba@penguin/T/#mc99839451d6841366619c4ec0d5af5264e2f6464 >> >> Code being useful is not enough. We must have people to maintain it >> adequately. This has not been the case for COLO in years. >> >> Deprecating a feature with intent to remove it is not a death sentence. >> It's a *suspended* death sentence: if somebody steps up to maintain it, >> we can revert the deprecation, or extend the grace period to give them a >> chance. >> >> I think we should deprecate COLO now to send a clear distress signal. >> The deprecation notice should explain it doesn't work, and will be >> removed unless people step up to fix it and to maintain it. This will >> ensure progress one way or the other. Doing nothing now virtually >> ensures we'll have the same discussion again later. >> >> "Broken for two releases without anyone noticing" and "maintainer absent >> for more than four years" doesn't exacltly inspire hope, though. We >> should seriously consider removing it right away. >> >> Lukas, can you give us hope? >> > > Hi Markus, > Maybe you missed something? > I think Lukas is ready to maintain this code in his previous emails. > https://lore.kernel.org/qemu-devel/20260115224516.7f0309ba@penguin/T/#mc99839451d6841366619c4ec0d5af5264e2f6464
Patch to MAINTAINERS or it didn't happen ;)
