Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20201026213040.3889546-1-arnd@kernel.org> <20201026213040.3889546-4-arnd@kernel.org>
 <03c5bc171594c884c903994ef82d703776bfcbc0.camel@sipsolutions.net>
In-Reply-To: <03c5bc171594c884c903994ef82d703776bfcbc0.camel@sipsolutions.net>
From:   Arnd Bergmann <arnd@kernel.org>
Date:   Tue, 27 Oct 2020 12:51:06 +0100
Message-ID: <CAK8P3a30T5o=EEnp3sdNM5iqsSaL6DKZONGBs+3S6g+36uHVzQ@mail.gmail.com>
Subject: Re: [PATCH net-next 04/11] wimax: fix duplicate initializer warning
To:     Johannes Berg <johannes@sipsolutions.net>
Cc:     Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>,
        linux-wimax@intel.com, "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Networking <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, Oct 27, 2020 at 8:22 AM Johannes Berg <johannes@sipsolutions.net> wrote:
>
> On Mon, 2020-10-26 at 22:29 +0100, Arnd Bergmann wrote:
> > From: Arnd Bergmann <arnd@arndb.de>
> >
> > gcc -Wextra points out multiple fields that use the same index '1'
> > in the wimax_gnl_policy definition:
> >
> > net/wimax/stack.c:393:29: warning: initialized field overwritten [-Woverride-init]
> > net/wimax/stack.c:397:28: warning: initialized field overwritten [-Woverride-init]
> > net/wimax/stack.c:398:26: warning: initialized field overwritten [-Woverride-init]
> >
> > This seems to work since all four use the same NLA_U32 value, but it
> > still appears to be wrong. In addition, there is no intializer for
> > WIMAX_GNL_MSG_PIPE_NAME, which uses the same index '2' as
> > WIMAX_GNL_RFKILL_STATE.
>
> That's funny. This means that WIMAX_GNL_MSG_PIPE_NAME was never used,
> since it is meant to be a string, and that won't (usually) fit into 4
> bytes...
>
> I suppose that's all an artifact of wimax being completely and utterly
> dead anyway. We should probably just remove it.

Makes sense. I checked
https://en.wikipedia.org/wiki/List_of_WiMAX_networks, and it appears
that these entries are all stale, after everyone has migrated to LTE
or discontinued their service altogether.

NetworkManager appears to have dropped userspace support in 2015
https://bugzilla.gnome.org/show_bug.cgi?id=747846, the
www.linuxwimax.org site had already shut down earlier.

WiMax is apparently still being deployed on airport campus
networks ("AeroMACS"), but in a frequency band that was not
supported by the old Intel 2400m (used in Sandy Bridge laptops
and earlier), which is the only driver using the kernel's wimax
stack.

Inaky, do you have any additional information about possible
users? If we are sure there are none, then I'd suggest removing
all the wimax code directly, otherwise it could go through
drivers/staging/ for a release or two (and move it back in case
there are users after all). I can send a patch if you like.

> So as far as the warning fix is concerned:
>
> Acked-by: Johannes Berg <johannes@sipsolutions.net>
>

Thanks!

        Arnd