Re: [PATCH net] ethtool: add and use message type for tunnel info reply

From: Jakub Kicinski
Date: Wed Sep 16 2020 - 20:45:46 EST

On Thu, 17 Sep 2020 01:04:10 +0200 (CEST) Michal Kubecek wrote:
> Tunnel offload info code uses ETHTOOL_MSG_TUNNEL_INFO_GET message type (cmd
> field in genetlink header) for replies to tunnel info netlink request, i.e.
> the same value as the request have. This is a problem because we are using
> two separate enums for userspace to kernel and kernel to userspace message
> types so that this ETHTOOL_MSG_TUNNEL_INFO_GET (28) collides with
> ETHTOOL_MSG_CABLE_TEST_TDR_NTF which is what message type 28 means for
> kernel to userspace messages.
> As the tunnel info request reached mainline in 5.9 merge window, we should
> still be able to fix the reply message type without breaking backward
> compatibility.
> Fixes: c7d759eb7b12 ("ethtool: add tunnel info interface")
> Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>

Ouch, sorry & thanks!

Reviewed-by: Jakub Kicinski <kuba@xxxxxxxxxx>