Re: [Qemu-devel] virtio block device and sysfs

[Ryan Harper <ryanh@us.ibm.com>]

* Marc Haber <mh+qemu-devel@zugschlus.de> [2010-09-13 03:56]:
> Hi John and Ryan,
> 
> On Tue, Jun 29, 2010 at 01:33:33PM -0500, Ryan Harper wrote:
> > We've got a sysfs 'serial' attribute for virtio-blk devices upstream[1].
> > I've got udev support for using this attribute to create disk/by-id (and
> > a fix for by-path) symlinks[2].  All that remains is to
> > re-spin/post the qemu virtio-blk serial patches[3] and get that in and
> > we'll have the full stack working as I've already tested libvirt (which
> > has disk serial support).
> 
> How is this going to work once the patches have been applied? Even
> qemu 0.11's -drive definition allows a serial= option, but currently
> (qemu-kvm 0.12.5, and 2.6.35.4 in the guest) the string passed to it
> isn't seen anywhere in the guest's /sys/block/vda.

It'll only be available to guests launched with newer qemu (0.13) as
virtio-blk serial support is a new feature.

> 
> My test call was
> kvm -cdrom ~/bigstuff/grml64-small_sid_20100913.iso \
>     -drive file=test.qcow2,if=virtio,media=disk,serial=foo
> 
> Greetings
> Marc
> 
> -- 
> -----------------------------------------------------------------------------
> Marc Haber         | "I don't trust Computers. They | Mailadresse im Header
> Mannheim, Germany  |  lose things."    Winona Ryder | Fon: *49 621 72739834
> Nordisch by Nature |  How to make an American Quilt | Fax: *49 3221 2323190

-- 
Ryan Harper
Software Engineer; Linux Technology Center
IBM Corp., Austin, Tx
ryanh@us.ibm.com