Re: [libvirt] [PATCH 3/4] Fix QEMU save/restore with block devices
On Thu, Apr 22, 2010 at 12:43:28PM +0100, Daniel P. Berrange wrote:
The save process was relying on use of the shell >> append
operator to ensure the save data was placed after the libvirt
header + XML. This doesn't work for block devices though.
Replace this code with use of 'dd' and its 'seek' parameter.
This means that we need to pad the header + XML out to a
multiple of dd block size (in this case we choose 512).
err, why ? As I pointed out dd seems just fine taking byte specified
offset, not necessarilly multiple of 512. The main problem I see with
this is that it does break the format and a somain saved (or managed
save) with 0.8.0 would not restore with 0.8.1.
I really want to understand why this is needed before going that route
because I see this as a serious compatibility break.
Daniel
--
Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/
daniel(a)veillard.com | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library http://libvirt.org/