On 09/11/2010 12:27 PM, Anthony Liguori wrote:
I think the better solution is to explicitly specific raw with nbd.
IOW, I think -drive file=nbd:localhost:1026,format=raw should work the
same way. I still feel slightly weird about probing happening with
nbd. It seems like it could only result in badness.
Yeah, w/o this patch, 'qemu-img create -f qcow2 -b nbd:localhost:1026 -o
backing_fmt=raw foo.img' doesn't generate any reads although if you drop
-o backing_fmt, it will.
Not sure I agree it's the most useful thing, but I'm not going to claim
it's never useful so this patch is not a good idea.
Regards,
Anthony Liguori
The specific scenario is migration. I'm using a copy-on-read file on
the destination and I want to be sure that I don't read any blocks
(since they're copied) until the source stops execution.
Regards,
Anthony Liguori
Stefan
