Re: [PATCH net] i40e: Prevent unwanted interface name changes

On Wednesday 08/20 at 11:41 +0200, Przemek Kitszel wrote:

On 8/20/25 08:42, Michal Schmidt wrote:

quoted

On Wed, Aug 20, 2025 at 6:30 AM Calvin Owens [off-list ref] wrote:

quoted

The same naming regression which was reported in ixgbe and fixed in
commit e67a0bc3ed4f ("ixgbe: prevent from unwanted interface name
changes") still exists in i40e.

Fix i40e by setting the same flag, added in commit c5ec7f49b480
("devlink: let driver opt out of automatic phys_port_name generation").

Fixes: 9e479d64dc58 ("i40e: Add initial devlink support")

But this one's almost two years old. By now, there may be more users
relying on the new name than on the old one.
Michal

And, more importantly, noone was complaining on the new name ;)

I'm just guessing with the Fixes tag, I didn't actually go back and try
to figure out when it broke. Let me double check, it would certainly
make more sense if it broke more recently.

But there are a lot of reasons I still think it should be fixed:

	1) I have ixgbe and i40e cards in one machine, the mis-match
	   between the interface naming pattern is irritating. Can't we
	   at least be consistent within the same manufacturer?

	2) The new names have zero real value: "enp2s0fX" vs
	   "enp2s0fXnpX", the "npX" prefix is entirely redundant for
	   this i40e card. Is there some case where it can have meaning?
	   I apologize if I'm glossing over something here, but it looks
	   entirely pointless. If it solved some real problem, I'd be a
	   lot more amenable to it.

	3) It's a userspace ABI regression which causes previously
	   working servers to be unable to connect to the network after
	   a simple kernel upgrade.

And, at the end of the day, it *is* a userspace ABI regression. If it
matters enough in ixgbe to warrant a *second* userspace ABI regression
to fix it, I think it warrants that in i40e too.

Thanks,
Calvin