Re: [PULL 00/16] migration queue

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
To: Leonardo Bras Soares Passos <leobras@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>,
	qemu-devel <qemu-devel@nongnu.org>,
	"Juan Quintela" <quintela@redhat.com>,
	"Peter Xu" <peterx@redhat.com>,
	"Stefan Hajnoczi" <stefanha@redhat.com>
Subject: Re: [PULL 00/16] migration queue
Date: Wed, 11 May 2022 09:55:14 +0100	[thread overview]
Message-ID: <Ynt58gRnsNJBXzfg@work-vm> (raw)
In-Reply-To: <CAJ6HWG5Mgaqt9dOVH-0-Y78x96HO5c-TevYeuN5xMvSQqj7W8Q@mail.gmail.com>

* Leonardo Bras Soares Passos (leobras@redhat.com) wrote:
> From a previous thread:
> 
> On Thu, Apr 28, 2022 at 1:20 PM Dr. David Alan Gilbert
> <dgilbert@redhat.com> wrote:
> >
> > Leo:
> >   Unfortunately this is failing a couple of CI tests; the MSG_ZEROCOPY
> > one I guess is the simpler one; I think Stefanha managed to find the
> > liburing fix for the __kernel_timespec case, but that looks like a bit
> > more fun!
> >
> > Dave
> 
> I thought Stefanha had fixed this bug, and we were just waiting for a
> new alpine rootfs/image with that fixed.
> Is that correct?
> 
> On Tue, May 10, 2022 at 7:43 AM Dr. David Alan Gilbert
> <dgilbert@redhat.com> wrote:
> >
> > * Daniel P. Berrangé (berrange@redhat.com) wrote:
> > > On Tue, May 10, 2022 at 10:58:30AM +0100, Dr. David Alan Gilbert wrote:
> [...]
> > >
> > > Yuk. That very much looks like a bug in liburing itself to me.
> > >
> > >
> > > We've exposed the latent bug by including linux/errqueue.h
> >
> > Yes, I think there was a thread after the 1st pull where Leo identified
> > the patch that fixed it; but it's not in that image.
> 
> I only fixed the MSG_ZEROCOPY missing define bug, as I got that
> Stefanha had already fixed the issue in liburing/alpine.
> 
> questions:
> - Has Stefanha really fixed that, and we are just waiting for a new
> image, or have I got that wrong?
> - How should I proceed with that?
>
> - If we proceed with fixing this up in alpine, will that require this
> patchset to be on pause until it's fixed there?

It needs to pass in CI; so yes.

> - If so, is there any suggestion on how to fix that in qemu code?
> (this header is needed because of SO_EE_* defines)

I've not actually looked at the detail of the failure; but yes I think
we need a qemu workaround here.

If there's no simple fix, then adding a test to meson.build to
conditionally disable liburing might be best; like the test code for
libcap_ng I guess (search in meson.build for libcap_ng.found  at around
line 540.

Dave

> Thank you all!
> 
> Best regards,
> Leo
> 
> >
> > Dave
> >
> > > With regards,
> > > Daniel
> > > --
> > > |: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
> > > |: https://libvirt.org         -o-            https://fstop138.berrange.com :|
> > > |: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|
> > >
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> >
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK