Re: [PATCH] net: ethernet: use ip_hdrlen() instead of bit shift

On Sat, Aug 03, 2024 at 10:47:35AM +0900, Moon Yeounsu wrote:

On Fri, Aug 2, 2024 at 11:15 PM Simon Horman [off-list ref] wrote:

quoted

On Fri, Aug 02, 2024 at 02:44:21PM +0900, Moon Yeounsu wrote:

quoted

`ip_hdr(skb)->ihl << 2` are the same as `ip_hdrlen(skb)`
Therefore, we should use a well-defined function not a bit shift
to find the header length.

It also compress two lines at a single line.

Signed-off-by: Moon Yeounsu <redacted>

Firstly, I think this clean-up is both correct and safe.  Safe because
ip_hdrlen() only relies on ip_hdr(), which is already used in the same code
path. And correct because ip_hdrlen multiplies ihl by 4, which is clearly
equivalent to a left shift of 2 bits.

Firstly, Thank you for reviewing my patch!

quoted

However, I do wonder about the value of clean-ups for what appears to be a
very old driver, which hasn't received a new feature for quite sometime

Oh, I don't know that...

quoted

And further, I wonder if we should update this driver from "Maintained" to
"Odd Fixes" as the maintainer, "Guo-Fu Tseng" [off-list ref],
doesn't seem to have been seen by lore since early 2020.

https://lore.kernel.org/netdev/20200219034801.M31679@cooldavid.org/ (local)

Then, how about deleting the file from the kernel if the driver isn't
maintained?

That is a bit more severe than marking it as being unmaintained
in MAINTAINERS. But I do agree that it should be considered.

Many people think like that (At least I think so)
There are files, and if there are issues, then have to fix them.
Who can think unmanaged files remain in the kernel?

And yet, they do exist. ☯