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

[Simon Horman <horms@kernel.org>]

On Sat, Aug 03, 2024 at 10:47:35AM +0900, Moon Yeounsu wrote:
> On Fri, Aug 2, 2024 at 11:15 PM Simon Horman <horms@kernel.org> wrote:
> >
> > On Fri, Aug 02, 2024 at 02:44:21PM +0900, Moon Yeounsu wrote:
> > > `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 <yyyynoom@gmail.com>
> >
> > 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!
> >
> > 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...
> >
> > And further, I wonder if we should update this driver from "Maintained" to
> > "Odd Fixes" as the maintainer, "Guo-Fu Tseng" <cooldavid@cooldavid.org>,
> > doesn't seem to have been seen by lore since early 2020.
> >
> > https://lore.kernel.org/netdev/20200219034801.M31679@cooldavid.org/
> 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. ☯