Re: [virtio] [PATCH] virtio-blk: restore VIRTIO_BLK_F_FLUSH and VIRTIO_BLK_F_CONFIG_WCE

[Paolo Bonzini <pbonzini@redhat.com>]

On 08/07/2015 13:04, Paolo Bonzini wrote:
> Not after reset, only after a cold restart (there was a
> crash---restoring from migration

is not an option

).  A lot more changes could happen
> between shutdown (doesn't matter if clean or crashy) and the next cold
> restart, and the guest can detect them the same way.
> 
> E.g. in one case the guest could detect that the kernel was updated via
> libguestfs.  In another the guest could detect that the storage
> (formerly in tmpfs, though the guest didn't know that) is now all zero.
>