On Wed, Sep 06, 2017 at 10:41:24AM +0300, Roman Kagan wrote: > On Tue, Sep 05, 2017 at 03:55:08PM +0100, Richard W.M. Jones wrote: > > Since qemu 2.10, qemu locks all drives even when they are opened > > readonly. This disables this locking in this safe case. > > > > Incomplete fix for > > https://bugzilla.redhat.com/show_bug.cgi?id=1417306 > > --- > > lib/launch-direct.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/lib/launch-direct.c b/lib/launch-direct.c > > index 3b848165c..e5465539d 100644 > > --- a/lib/launch-direct.c > > +++ b/lib/launch-direct.c > > @@ -221,8 +221,11 @@ add_drive_standard_params (guestfs_h *g, struct > > backend_direct_data *data, > > file = guestfs_int_drive_source_qemu_param (g, &drv->src); > > append_list_format ("file=%s", file); > > > > - if (drv->readonly) > > + if (drv->readonly) { > > append_list ("snapshot=on"); > > + if (guestfs_int_version_ge (&data->qemu_version, 2, 10, 0)) > > + append_list ("locking=off"); > > Don't we have a way to enumerate supported options?
Yes, although it's difficult to do: https://www.redhat.com/archives/libguestfs/2017-September/msg00039.html Rich. > Depending on QEMU version is not going to play nice with vendor-shipped > QEMU where features are often backported. > > > + } > > append_list_format ("cache=%s", > > drv->cachemode ? drv->cachemode : "writeback"); > > if (drv->src.format) > > Roman. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top _______________________________________________ Libguestfs mailing list [email protected] https://www.redhat.com/mailman/listinfo/libguestfs
