Re: [libvirt] [PATCH 2/3] scsi-disk: Add device_id property

On Fri, Jan 25, 2019 at 18:46:52 +0100, Kevin Wolf wrote: > The new device_id property specifies which value to use for the vendor > specific designator in the Device Identification VPD page. > > In particular, this is necessary for libvirt to maintain guest ABI > compatibility when no serial number is given and a VM is switched from > -drive (where the BlockBackend name is used) to -blockdev (where the > vendor specific designator is left out by default). > > Signed-off-by: Kevin Wolf <kwolf(a)redhat.com&gt; > --- > hw/scsi/scsi-disk.c | 24 ++++++++++++++++-------- > 1 file changed, 16 insertions(+), 8 deletions(-) [...] > @@ -2904,7 +2910,9 @@ static const TypeInfo scsi_disk_base_info = { > DEFINE_PROP_STRING("ver", SCSIDiskState, version), \ > DEFINE_PROP_STRING("serial", SCSIDiskState, serial), \ > DEFINE_PROP_STRING("vendor", SCSIDiskState, vendor), \ > - DEFINE_PROP_STRING("product", SCSIDiskState, product) > + DEFINE_PROP_STRING("product", SCSIDiskState, product), \ > + DEFINE_PROP_STRING("device_id", SCSIDiskState, device_id) This adds the property only to 'scsi-disk', whereas libvirt will use 'scsi-cd' or 'scsi-hd' depending on the media type if the 'scsi-cd' device is detected. The following logic decides: https://libvirt.org/git/?p=libvirt.git;a=blob;f=src/qemu/qemu_command.c;h... This brings multiple questions: