Re: [libvirt] [PATCH 0/2] Disable floppy disk for PowerPC VMs

On Fri, 2015-07-24 at 15:29 -0400, Kothapally Madhu Pavan wrote: > This is an attempt to fix: > Libvirt BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1180486 > > Libvirt currently assumes ISA_based floppy disks to be available > across all > architectures and machine types. However, PowerPC Book 3S compatible > ('ie pseries) > virtual machines do not support Floppy disks. > > This patch series prevents libvirt from launching ppc64[le] -based > 'pseries' > VMs with floppy devices. Hi, sorry for not replying right away. I started looking into that bug a while ago but I got sidetracked shortly afterwards, so I don't have much to show for it. I'd like to share my opinion on the matter anyway. I believe you're basically following the right approach, eg. avoid setting floppy-related capabilities and erroring out afterwards if attempts are made to use devices that require such capabilites. However, I think the implementation should be a little more generic: ideally, the code would contain no references to the ppc64 architecture and whether or not floppy disks are be allowed would be determined by probing the QEMU binary. Writing the code this way would allow us to handle automatically other architectures where floppy disks do not make sense[1] and situations where floppy support is not available[2]. If that turns out not to be possible or practical, at the very least the check should be performed in one single spot, and not replicated a dozen times thorough the library.So,