To fix the actual bug, it was necessary to make networkPlugBandwidth() be
called also for 'bridge'-type networks implemented using macvtap's 'bridge'
mode (previously it was only called for those implemented on top of an
existing bridge).

However, it seems beneficial to call it for other network types as well,
at least because it removes an inconsistency in types of bandwidth
configuration changes permissible in inactive and active domain configs.

Signed-off-by: Pavel Mores <pmores@redhat.com>
---
 src/network/bridge_driver.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 3b70e52afd..513ae59e68 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -4571,8 +4571,6 @@ networkAllocatePort(virNetworkObjPtr obj,
             return -1;
         }
 
-        if (networkPlugBandwidth(obj, &port->mac, port->bandwidth, &port->class_id) < 0)
-            return -1;
         break;
 
     case VIR_NETWORK_FORWARD_HOSTDEV: {
@@ -4637,8 +4635,6 @@ networkAllocatePort(virNetworkObjPtr obj,
                 }
             }
 
-            if (networkPlugBandwidth(obj, &port->mac, port->bandwidth, &port->class_id) < 0)
-                return -1;
             break;
         }
 
@@ -4736,6 +4732,9 @@ networkAllocatePort(virNetworkObjPtr obj,
         return -1;
     }
 
+    if (networkPlugBandwidth(obj, &port->mac, port->bandwidth, &port->class_id) < 0)
+        return -1;
+
     if (virNetworkObjMacMgrAdd(obj, driver->dnsmasqStateDir,
                                port->ownername, &port->mac) < 0)
         return -1;
-- 
2.24.1

On 2/10/20 5:10 PM, Pavel Mores wrote:
> To fix the actual bug, it was necessary to make networkPlugBandwidth() be
> called also for 'bridge'-type networks implemented using macvtap's 'bridge'
> mode (previously it was only called for those implemented on top of an
> existing bridge).
> 
> However, it seems beneficial to call it for other network types as well,
> at least because it removes an inconsistency in types of bandwidth
> configuration changes permissible in inactive and active domain configs.
> 
> Signed-off-by: Pavel Mores <pmores@redhat.com>
> ---
>   src/network/bridge_driver.c | 7 +++----
>   1 file changed, 3 insertions(+), 4 deletions(-)
> 

I'd mention in the commit message that this is safe to do, because if no 
QoS is set, then the function is NOP. Or something among those lines. It 
might help us in the future to pin a point in time when this used to work.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

Michal