This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] [PATCH 0/3] RFC: PCIe IO space multiplexing for bootable

To: Yuji Shimada <shimada-yxb@xxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH 0/3] RFC: PCIe IO space multiplexing for bootable pass through HVM domain
From: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>
Date: Thu, 2 Apr 2009 16:56:42 +0900
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Ian.Jackson@xxxxxxxxxxxxx
Delivery-date: Thu, 02 Apr 2009 00:57:10 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20090402161127.5C9D.27C06F64@xxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <20090402040128.GA31513@xxxxxxxxxxxxxxxxxxxxxxxxxx> <20090402161127.5C9D.27C06F64@xxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.6i
On Thu, Apr 02, 2009 at 04:12:56PM +0900, Yuji Shimada wrote:
> On Thu, 2 Apr 2009 13:01:28 +0900
> Isaku Yamahata <yamahata@xxxxxxxxxxxxx> wrote:
> > 
> > Hi all. This is for PCIe IO space multiplexing. Please comment.
> > 
> > It is not uncommon that a big iron for server consolidation has
> > many (e.g. > 16) PCIe slots. It will hold many domains, and
> > the administrator wants them to boot from pass through devices.
> > But currently up to 16 hvm domains can boot from pass through device.
> > 
> > This patch series addresses this issue by multiplexing IO space access.
> > The patches are composed of
> >     Linux part: IO space ressignment code and multiplexing driver
> >     xen part:   udev script for the driver
> >     ioemu part: make use of the PCIe io space multiplexing driver
> > 
> > 
> > Usage:
> > Add dom0 kernel command line specifying the pass through devices by
> >   guestiomuldev=[<segment>:]<bus>:<dev>[,[<segment:><bus>:dev]][,...]
> > (Don't forget add related options. pciback.hide, reassign_resources,
> > reassigndev or guestdev.)
> It is nice to add "iomul" flag to "guestdev=" boot parameter, because
> segment# and bus# can be changed on rebooting. In addition to this,
> specifying pciback.hide, reassigndev and guestioemuldev is redundant.
> This is a example.
>         guestdev=PNP0A03:0-02.0+iomul,PNP0A03:0-1e.0+iomul

That sounds a good idea.
I haven't addressed the option integration yet because I'd like to verify
the functionality itself first.

My IO sharing code handles devices in the unit of device (not function),
so ".<func>" isn't necessary. The parser will be modified slightly.


> Incidentally, I will submit the patch to use device path to assign
> devices to guest domain as discussed in xen-devel, after xen 3.4 is
> released.
> Thanks,


Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>