[fedora-virt] guestfish, libguestfs, ext4 and bad perms on /dev/kvm

Robert P. J. Day rpjday at crashcourse.ca
Wed Apr 22 21:27:12 UTC 2009

On Wed, 22 Apr 2009, Richard W.M. Jones wrote:

> On Wed, Apr 22, 2009 at 03:20:14PM -0400, Robert P. J. Day wrote:
> >   in short, ext4 filesystem support now appears to work, but
> > there's still the issue (perhaps addressed earlier) that non-root
> > users don't have access to KVM support but, from the perspective
> > of libguestfs, does that really matter?
> KVM makes things do a lot faster, which is always nice.

  which inspires the obvious question -- is kvm *required* for any
libquestfs functionality?  speed is always nice, but it's important to
know that, even if things are slow, they will still work equally well.

> You can
> do the following:
>   # chmod o+rw /dev/kvm
> You have to do (just) that command as root, but after that qemu-kvm
> and guestfish itself can all be run as non-root, and will benefit
> from KVM acceleration.

  or, for permanence, add the appropriate udev rule, which is what i
prefer, since it persists across reboots.

> > p.s.  i could have sworn i didn't get that /dev/kvm perms error
> > yesterday. did something about that change since version 1.0.4?
> Yes, libguestfs changed to detect and enable KVM by default.
> Before today it wasn't using KVM at all.

  gotcha, thanks.


Robert P. J. Day                               Waterloo, Ontario, CANADA

        Linux Consulting, Training and Annoying Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Linked In:                             http://www.linkedin.com/in/rpjday
Twitter:                                       http://twitter.com/rpjday

More information about the Fedora-virt mailing list