[RFC] Remove Kernel Network Interface (KNI)

[Thomas Monjalon]

13/01/2023 18:13, Stephen Hemminger:
> On Fri, 13 Jan 2023 09:12:16 +0100
> Thomas Monjalon <thomas at monjalon.net> wrote:
> 
> > 13/01/2023 06:03, Stephen Hemminger:
> > > The Linux special network driver for kernel networking has been
> > > a long term problem for DPDK. The performance benefits of KNI
> > > are available via virtio-user and XDP, and the simpler kernel
> > > interface via TAP is also available.
> > > 
> > > This driver has required lots of effort to keep up with the
> > > kernel API changes. And the overall architecture of the driver
> > > is fundamentally insecure and has unfixable locking and data
> > > race problems. No developer has been willing to do extensive
> > > tests or be the maintainer.
> > > 
> > > In short, the time has come to do some early spring cleaning
> > > and remove KNI from DPDK 23.03.  
> > 
> > In doc/guides/rel_notes/deprecation.rst it is announced
> > to be removed in 23.11. Let's keep this RFC for later :)
> > 
> > 
> 
> For 23.03 could we add a deprecation log message when library is
> used and when kernel module is loaded.

We already have a message in the lib:

int
rte_kni_init(unsigned int max_kni_ifaces __rte_unused)
{
	RTE_LOG(WARNING, KNI, "WARNING: KNI is deprecated and will be removed in DPDK 23.11\n");

It is a good idea to add a message in the kernel module loading.