Re: [Qemu-ppc] Bug with REPORT LUNS in IBM VSCSI

[Nathan Whitehorn]

On Oct 3, 2013, at 3:05 AM, Paolo Bonzini wrote:

> Il 02/10/2013 18:05, Nathan Whitehorn ha scritto:
> > > Both Linux and Windows scan each channel separately.  Linux, in
> > > addition, does not expect REPORT LUNS to use the logical unit  
> > > addressing
> > > method in the returned list of LUNs.  The driver converts the
> > > channel/target/LUN tuple to that addressing method when it builds  
> > > the
> > > SRP commands.
> >
> > Right, I see that. And this is an approach that works, but is really
> > really ugly since it is assumes a fixed range of possible LUNs. It  
> > also
> > relies on some kind of inference about which LUNs actually exist  
> > since
> > SRP has no mechanism to report a non-existant "target" back to the  
> > host
> > (since there is only one target, it can't have non-existant  
> > targets, so
> > there is no mechanism for this).
>
> I can certainly change REPORT LUNS to report all subtargets, but I  
> need
> to be careful and not break Linux...
>
> Paolo

I think this is the way it works on hardware, so the change should not  
break anything. Please let me know if I can do anything to help and  
thanks for looking into this.
-Nathan