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Date:   Mon, 9 Jan 2023 08:04:23 +0100
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Subject: Re: [PATCH net-next] Remove DECnet support from kernel
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To:     Stephen Hemminger <stephen@networkplumber.org>,
        netdev@vger.kernel.org
Cc:     David Ahern <dsahern@kernel.org>, Jonathan Corbet <corbet@lwn.net>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Nicholas Piggin <npiggin@gmail.com>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        Florian Westphal <fw@strlen.de>, Borislav Petkov <bp@suse.de>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Damien Le Moal <damien.lemoal@opensource.wdc.com>,
        Muchun Song <songmuchun@bytedance.com>,
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        Xin Long <lucien.xin@gmail.com>,
        Juergen Gross <jgross@suse.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Nathan Fontenot <nathan.fontenot@amd.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Suma Hegde <suma.hegde@amd.com>, Chen Yu <yu.c.chen@intel.com>,
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        Stefano Garzarella <sgarzare@redhat.com>,
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        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
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References: <20220818004357.375695-1-stephen@networkplumber.org>
From:   Jiri Slaby <jirislaby@kernel.org>
In-Reply-To: <20220818004357.375695-1-stephen@networkplumber.org>
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On 18. 08. 22, 2:43, Stephen Hemminger wrote:
> DECnet is an obsolete network protocol that receives more attention
> from kernel janitors than users. It belongs in computer protocol
> history museum not in Linux kernel.
> 
> It has been "Orphaned" in kernel since 2010. The iproute2 support
> for DECnet was dropped in 5.0 release. The documentation link on
> Sourceforge says it is abandoned there as well.
> 
> Leave the UAPI alone to keep userspace programs compiling.
> This means that there is still an empty neighbour table
> for AF_DECNET.
> 
> The table of /proc/sys/net entries was updated to match
> current directories and reformatted to be alphabetical.
> 
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> Acked-by: David Ahern <dsahern@kernel.org>

...
>   include/uapi/linux/dn.h                       |  149 -
>   include/uapi/linux/netfilter_decnet.h         |   72 -

Hi,

this breaks userspace. Some projects include linux/dn.h:

   https://codesearch.debian.net/search?q=include.*linux%2Fdn.h&literal=0


I found Trinity fails to build:
  net/proto-decnet.c:5:10: fatal error: linux/dn.h: No such file or 
directory
      5 | #include <linux/dn.h>


Should we provide the above as empty files?

thanks,
-- 
js
suse labs