[ovs-dev] [PATCH v4] netdev-linux: do not send packets to down tap ifaces.

[Ben Pfaff]

On Wed, Jan 24, 2018 at 10:10:16AM -0200, Flavio Leitner wrote:
> On Tue, Jan 23, 2018 at 12:31:53PM -0800, Ben Pfaff wrote:
> > On Wed, Jan 17, 2018 at 10:09:58PM -0200, Flavio Leitner wrote:
> > > Today OVS pushes packets to the TAP interface ignoring its
> > > current state. That works because the kernel will return -EIO
> > > when it's not UP and OVS will just ignore that as it is not
> > > an OVS issue.
> > > 
> > > However, it causes a huge impact when broadcasts happen when
> > > using userspace datapath accelerated with DPDK (e.g.: action
> > > NORMAL).  This patch improves the situation by checking the
> > > TAP's interface state before issueing any syscall.
> > > 
> > > However, there might be use-cases moving interfaces to other
> > > networking namespaces and in that case, OVS can't retrieve
> > > the iface state (sets it to DOWN). That would stop the traffic
> > > breaking the use-case. This patch relies on netlink notifications
> > > to find out if the device is local or not. When it's local, the
> > > device state is checked otherwise it will behave as before.
> > > 
> > > Signed-off-by: Flavio Leitner <fbl at sysclose.org>
> > 
> > I applied this to master yesterday.  (It looks like I forgot to send an
> > email about it at the time.)  Thanks!
> 
> Thanks Ben, any chance to get this patch applied to branch-2.9?

Sure, done.