[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PULL 8/9] static checker: e1000-82540em got aliased to
From: |
Dr. David Alan Gilbert |
Subject: |
Re: [Qemu-devel] [PULL 8/9] static checker: e1000-82540em got aliased to e1000 |
Date: |
Tue, 5 Apr 2016 14:32:34 +0100 |
User-agent: |
Mutt/1.5.24 (2015-08-30) |
* Amit Shah (address@hidden) wrote:
> On (Tue) 23 Feb 2016 [15:02:58], Jason Wang wrote:
> > >> This means that 2.5 cannot migrate 2.4 virtual machines, right? Is that
> > >> something we want to rectify in 2.6 by making e1000-82540em an alias of
> > >> e1000 (instead of the other way round)?
> > > You're right; I misread it. With that commit (8304402033):
> > >
> > > 2.4 with e1000-82540em will not migrate to 2.5 with e1000-82540em.
> > >
> > > This is despite they're aliased (so the cmdline is backward
> > > compatible), but the migration device name actually changed.
> > >
> > > Of course, 2.5->2.4 will also not work.
> > >
> > > Since 2.4 emits 'e1000-82540em' as the device name in the migration
> > > stream, and 2.5 emits just 'e1000', we have two different names for
> > > the same device in two versions.
> > >
> > > To fix this, we'll need a hack on the dest side to allow e1000 and
> > > e1000-82540em in the migration stream for the device, and this can be
> > > done for 2.6 and 2.5.stable.
> > >
> > > Jason, can you attempt this?
> > >
> > Sure, but just need to understand the "problem". If I understand this
> > correctly, the issue only happen for JSON description at the end of
> > migration stream, and it won't break migration in fact?
>
> No, this does break migration.
>
> The stream contained 'e1000-82540em' as the section header for the
> device earlier. It now only has 'e1000'. So a newer qemu will only
> accept 'e1000', but not 'e1000-82540em' (from an older release).
OK, so do we need to get this fixed for 2.6 - i.e. now.
Dave
>
> Amit
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK
- Re: [Qemu-devel] [PULL 8/9] static checker: e1000-82540em got aliased to e1000,
Dr. David Alan Gilbert <=