[libvirt] [PATCH 2/2] qemuDomainChangeNet: Forbid changing MTU
https://bugzilla.redhat.com/show_bug.cgi?id=1447618
Currently, any attempt to change MTU on an interface that is
plugged to a running domain is silently ignored. We should either
do what's asked or error out. Well, we can update the host side
of the interface, but we cannot change 'host_mtu' attribute for
the virtio-net device. Therefore we have to error out.
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/qemu/qemu_hotplug.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index 8066acae3..d46956d98 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -3138,6 +3138,12 @@ qemuDomainChangeNet(virQEMUDriverPtr driver,
/* vlan can be modified, and will be checked later */
/* linkstate can be modified */
+ if (olddev->mtu != newdev->mtu) {
+ virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
+ _("cannot modify MTU"));
+ goto cleanup;
+ }
+
/* allocate new actual device to compare to old - we will need to
* free it if we fail for any reason
*/
--
2.13.0