On Thu, Feb 20, 2025 at 05:59:10PM +0100, Stefano Brivio wrote: > On Thu, 20 Feb 2025 10:28:20 -0500 > "Michael S. Tsirkin" <m...@redhat.com> wrote: > > > On Fri, Jan 24, 2025 at 05:03:27PM +0100, Stefano Brivio wrote: > > > But I don't understand why we're leaving this as it is. > > > > So that people notice if there's some backend problem and > > announcements are not going out. should help debug migration > > issues. which we had, so we added this :) > > The message mentions that the back-end fails to do something it didn't > and can't even do, that's (one reason) why it's wrong (and confusing) > and this patch is obviously correct. > > Perhaps the commit title isn't entirely accurate (it should say "when > unsupported", I guess) but it's somewhat expected to sacrifice detail > in the name of brevity, there. A glimpse at the message is enough. > > Laurent now added a workaround in passt to pretend that we support > VHOST_USER_PROTOCOL_F_RARP by doing nothing in the callback, report > success, and silence the warning: > > https://passt.top/passt/commit/?id=dd6a6854c73a09c4091c1776ee7f349d1e1f966c > > but having to do this kind of stuff is a bit unexpected while > interacting with another opensource project. > > -- > Stefano
let me explain. historically backends did not support migration. then migration was added. as it was assumed RARP is required, we did not add a feature flag for "supports migration" and instead just assumed that VHOST_USER_PROTOCOL_F_RARP is that. If you silence the warning you silence it for old backends with no migration support. If you want a new flag "migration with no RARP", be my guest and add it. Or if you want to add documentation explaining the meaning better and clarifying the message. -- MST
