Re: [libvirt] PATCH: Support setting a disk drive serial (number)

Daniel P. Berrange wrote: >All hard disks (IDE, SCSI, USB, VirtIO) have a concept of a serial number >which is intended to uniquely identify them. If you mean this off, QEMU >just makes up a serial on the fly. THis is not guarenteed to be stable >across guest reboots with hardware changes. It is thus desirable to be >able to specify this in libvirt XML. To that end, this patch allows >for a <serial> element inside a disk > > <disk type='file' device='disk'> > <source > file='/media/lacie-500-disk-2/virtual-machines/scratch5.img'/> > <target dev='vda' bus='virtio'/> > <serial>dan123virtio</serial> > </disk> > >the contents is free-form. It implemenmts this for the QEMU driver for >any disk using -drive style args. Unfortunately this excludes USB disk, >even though internally QEMU can set a serial for these, the -usbdevice >syntax does not allow it > >Daniel > >* docs/schemas/domain.rng: Add <serial> element to disks >* src/domain_conf.h, src/domain_conf.c: XML parsing and > formatting for disk serial numbers >* src/qemu_conf.c: Set serial number when launching guests >* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-shared.args, > tests/qemuxml2argvdata/qemuxml2argv-disk-drive-shared.xml: Add > serial number to XML test

This patch seems like a very good idea to me. I'm surprised it doesn't cause more grief if the serial # keeps changing. I didn't review the code too closely, but a definite ACK to the functionality, and I saw no problems with the implementation in the quick look I took.

As a possible additional feature, in the case of an entire device being assigned to the guest, have you considered passing through the serial of the underlying device? The serial is available in the nodedev XML.