[libvirt] 'build' on FS pool now unconditionally formats?

Daniel Veillard veillard at redhat.com
Thu Feb 25 12:19:54 UTC 2010


On Wed, Feb 24, 2010 at 03:51:45PM -0500, Cole Robinson wrote:
> Hi guys,
> 
> Looking at the new FS pool build options and talking with Dave, I see that
> calling PoolBuild on an FS pool now unconditionally calls mkfs. This is really
> bad when mixed with virt-manager: previously, we assumed the FS build command
> was always non destructive (at most it created a directory), so we called it
> every time, and didn't even allow users to opt out, since there wasn't a use
> case that called for it.
> 
> This new formatting behavior really needs to be opt in, otherwise all
> virt-manager versions creating an FS pool can destroy data.
> 
> Just FYI, for disk pools (and certain LVM configurations) where this operation
> has always been destructive, we default to build=off, and loudly warn the user
> if they choose otherwise. We can do that with this new option as well, but the
> previous behavior really needs to be reinstated IMO (and before the new release).
> 
> I fully accept that this could be a bug in virt-manager's assumptions of the
> build command, but even consider a virsh user: previously build just created a
> directory, now it formats a partition, without any XML change.

I was initially reluctant of changing the behaviour, and asked to use a
flag to keep the original default semantic. I got convinced that noone
could rely on it because the function was basically incomplete. But since
virt-manager ships with an expectation on the previous behaviour, I
revert my position, we need to add a _FORMAT = 4 flag for this call and
only call mkfs if that flag is passed. Fix is trivial we should not
push 0.7.7 without it,

 thanks !

Daniel

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
daniel at veillard.com  | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library  http://libvirt.org/




More information about the libvir-list mailing list