RE: [PATCH] net/filter: Enable the vnet_hdr_support by default

[Zhang, Chen]

> -----Original Message-----
> From: Markus Armbruster <armbru@redhat.com>
> Sent: Wednesday, November 10, 2021 2:21 PM
> To: Zhang, Chen <chen.zhang@intel.com>
> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu-
> devel@nongnu.org>; Li Zhijian <lizhijian@cn.fujitsu.com>
> Subject: Re: [PATCH] net/filter: Enable the vnet_hdr_support by default
> 
> "Zhang, Chen" <chen.zhang@intel.com> writes:
> 
> >> -----Original Message-----
> >> From: Markus Armbruster <armbru@redhat.com>
> >> Sent: Wednesday, November 10, 2021 1:07 PM
> >> To: Zhang, Chen <chen.zhang@intel.com>
> >> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu-
> >> devel@nongnu.org>; Li Zhijian <lizhijian@cn.fujitsu.com>
> >> Subject: Re: [PATCH] net/filter: Enable the vnet_hdr_support by
> >> default
> >>
> >> Zhang Chen <chen.zhang@intel.com> writes:
> >>
> >> > This patch make filters and colo-compare module support vnet_hdr by
> >> > default. And also support -device non-virtio-net(like e1000.).
> >> > But it can't avoid user manual configuration error between
> >> > different filters when enable/disable virtio-net-pci.
> >> >
> >> > Signed-off-by: Zhang Chen <chen.zhang@intel.com>
> >>
> >> Have you considered backward compatibility?  Can it break usage that
> >> now works?
> >
> > Yes, this patch fully guarantees the compatibility as Jason's comments.
> > Original usage still works.
> 
> Worth a brief explanation in the commit message?

OK. Add following statement to commit message:
This patch make filters and colo-compare module support vnet_hdr by
default. And also support -device non-virtio-net(like e1000.). Because
when enabled the support will make the vnet_hdr_len field become must-delivery
part of filter transfer protocol(even 0 in use -device e1000). It fully 
guarantees the
compatibility for management layer like libvirt.
But it still can't avoid user manual configuration error between
different filters connected when enable/disable vnet_hdr_support.

How about this explanation?

By the way, please let me know your comments on filter passthrough series:
https://mail.gnu.org/archive/html/qemu-devel/2021-08/msg01393.html
If OK, I will update it.

Thanks
Chen