On 16/09/2016 01:42, John Snow wrote: > One more try. > > The move to blk_flush altered the behavior of migration and flushing > nodes that are not reachable via the guest, but are still reachable > via QEMU and may or may not need to be flushed. > > This is likely the simplest solution for now until we nail down our > policy a bit more. > > This is intended for 2.6.2 and/or 2.7.1, to fix problems with libvirt > et al being unable to migrate QEMU when the CDROM tray is open. > > v3: > Trying to take a hint from Kevin, reinstating bdrv_flush_all. > If it's not what we want, we can try moving back to v2, > acknowledging that a nicer solution in the future: > (A) Can skip flushing on devices that just don't need it, and > (B) Optionally institutes some sort of flush-on-eject policy.
If you move flushing from platform_fixed_ioport_writew's blk_flush_all to blk_flush calls in pci_piix3_xen_ide_unplug, you can get rid of blk_flush_all completely. Paolo
