[Xen-devel] Re: [patch] Fix xm pci-detach for inactive devices

["Zhai, Edwin" <edwin.zhai@xxxxxxxxx>]

I see.
Looks fine for me.

Thanks,


Simon Horman wrote:
> On Tue, May 26, 2009 at 01:15:51PM +0800, Zhai, Edwin wrote:
>   
> > Simon,
> > What does inactive domain means?
> > How does it lead an invalid vslot?
> >     
> Hi Edwin,
>
> An inactive domain means one that has been created
> but is stopped. An invalid vslot can occur in this case
> if the vslot is to be automatically assigned by qemu-dm.
> This is because the request will not be sent to qemu-dm
> until the domain is started.
>
> e.g.:
>
> $ xm new hvm.conf
> $ xm pci-attach hvm 00:1d.0
> $ xm pci-list hvm
> -    0x0      0x00  0x1d   0x0   <- '-' means the vslot has not been determined
> $ xm pci-detach hvm 00:1d.0      <- will fail without this change
>
> Or alternatively:
>
> $ xm new hvm.conf
> $ xm pci-attach hvm 00:1d.0
> $ xm pci-list hvm
> -    0x0      0x00  0x1d   0x0   <- '-' means the vslot has not been determined
> $ xm start hvm
> $ xm pci-list hvm
> 0x7  0x0      0x00  0x1d   0x0   <- vslot 0x7 was allocated after the
>                                     domain started
> $ xm pci-detach hvm 00:1d.0      <- will work with or without this patch
>
> Attaching devices to inactive domains was recently
> fixed (added?) by Kanno-san.
>
>   
> > Simon Horman wrote:
> >     
> > > In the case where a device is attached to an inactive domain
> > > and then removed before the domain is activated it won't have
> > > a vslot assigned, but it should still be valid to remove it.
> > >
> > > I don't think that there are any other cases where vslot can
> > > be invalid.
> > >
> > > Lightly tested
> > >
> > > Cc: Zhai Edwin <edwin.zhai@xxxxxxxxx>
> > > Cc: Masaki Kanno <kanno.masaki@xxxxxxxxxxxxxx>
> > > Signed-off-by: Simon Horman <horms@xxxxxxxxxxxx>
> > >
> > > Index: xen-unstable.hg/tools/python/xen/xend/XendDomainInfo.py
> > > ===================================================================
> > > --- xen-unstable.hg.orig/tools/python/xen/xend/XendDomainInfo.py        
> > > 2009-05-26 14:37:15.000000000 +1000
> > > +++ xen-unstable.hg/tools/python/xen/xend/XendDomainInfo.py     2009-05-26 
> > > 14:37:18.000000000 +1000
> > > @@ -1130,9 +1130,6 @@ class XendDomainInfo:
> > >          if devnum >= pci_len:
> > >              raise VmError("Device @ vslot 0x%x doesn't exist." % (vslot))
> > >  -        if vslot == AUTO_PHP_SLOT:
> > > -            raise VmError("Device @ vslot 0x%x doesn't support hotplug." % 
> > > (vslot))
> > > -
> > >          # Check the co-assignment.
> > >          # To pci-detach a device D from domN, we should ensure: for each DD in 
> > > the
> > >          # list of D's co-assignment devices, DD is not assigned (to domN).
> > >
> > >   
> > >       
> > --
> > best rgds,
> > edwin
> >     
>   
--
best rgds,
edwin


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel