Re: [Xen-devel] [PATCH v3 3/4] docs: add pvscsi.txt

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Fri, Mar 06, 2015 at 04:11:20PM +0100, Olaf Hering wrote:
> On Fri, Mar 06, Wei Liu wrote:
> 
> > On Fri, Mar 06, 2015 at 10:45:55AM +0100, Olaf Hering wrote:
> > > +== TODO ===
> > > +
> > > +How to do live migration?
> > > + - pdev will likely be evaluated again on the target host if it came from
> > > +   domU.cfg. But what about pdev from 'xl scsi-attach pdev vdev'? Its 
> > > required
> > > +   to adjust h:c:t:l on the target host.
> > > +
> > > +How to handle FIXME in libxl_retrieve_domain_configuration?
> > > + - "MERGE(vscsi, vscsis, COMPARE_DEVID, {});", when does this code run?
> > > + 
> > 
> > I don't think this kind of information that relates to libxl internal
> > belongs here.
> 
> Its the overall TODO list, it has to go somewhere. And it will be
> removed once its empty.
> 
> > Anyway, to answer you question. libxl_retrieve_domain_configuration is
> > called by xl when you do migration / detailed domain configuration
> > listing etc.
> 
> How can the values diverge? With commands like 'scsi-attach'?
> 

Because there are states that are only available in xenstore.  We want
to reflect that in the retrieved configuration. I think at the moment
only disk needs such handling. If you don't think vscsi values can
diverge you can just use {}.

> > I think the comment above MERGE macro states what it does and how to use
> > it. Is there anything that's not clear to you?
> 
> I think for vscsi it has to compare the vdev h:c:t:l part, just as disk
> compares xvda. I will look at this once I'm done with libvirt
> integration.

The point is to identify a device from guest's PoV. h:c:t:l might be
good enough.

Wei.

> 
> Olaf

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel