Re: Xen/AoE skb frag array incompatibility

[Keir Fraser <keir@xensource.com>]

Is there a clear technical description of what the problem is? I see three
problems vaguely referred to in this email:
 1. Build failure on skb_linearize()
 2. Warnings about 'can't schedule work'
 3. Some unspecified problem with frag lists

If someone digs into the problem a bit and points us at some code we can
probably advise what should be done.

 -- Keir

On 8/12/06 2:00 am, "Tracy R Reed" <treed@ultraviolet.org> wrote:

> Greetings, Xen developers!
> 
> I have been using AoE with Xen to great effect and I am very pleased
> with how the whole system has worked out. The two technologies really
> complement each other. I consider it the ultimate setup. Aside from the
> network switch (eventually to be remedied) my serving infrastructure has
> zero single points of failure.
> 
> However, this virtualization paradise has a flaw: There seems to be some
> sort of incompatibility in the way AoE uses the skb frag array in the
> latest version of AoE (6-40) and in the way Xen uses it. This causes new
> AoE block devices to fail to be accessible among potentially other problems.
> 
> Is anyone aware of this problem? It is not clear to me if it is a
> problem with Xen or if the fault lies in AoE. I have looked into it a
> bit but my kernel hacking talents are rather meager. Attached is a
> recent email from the AoE list discussing it. If you have any
> suggestions for the AoE folks they can be reached over at
> aoetools-discuss@lists.sourceforge.net