kernel/git/stable/linux.git/Documentation/networking/dccp.rst, branch masterLinux kernel stable treehttps://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=master2025-04-12T01:58:10+00:00net: Retire DCCP socket.2025-04-12T01:58:10+00:00Kuniyuki Iwashimakuniyu@amazon.com2025-04-10T02:36:45+00:00urn:sha1:2a63dd0edf388802074f1d4d6b588a3b4c380688
DCCP was orphaned in 2021 by commit 054c4610bd05 ("MAINTAINERS: dccp:
move Gerrit Renker to CREDITS"), which noted that the last maintainer
had been inactive for five years.
In recent years, it has become a playground for syzbot, and most changes
to DCCP have been odd bug fixes triggered by syzbot. Apart from that,
the only changes have been driven by treewide or networking API updates
or adjustments related to TCP.
Thus, in 2023, we announced we would remove DCCP in 2025 via commit
b144fcaf46d4 ("dccp: Print deprecation notice.").
Since then, only one individual has contacted the netdev mailing list. [0]
There is ongoing research for Multipath DCCP. The repository is hosted
on GitHub [1], and development is not taking place through the upstream
community. While the repository is published under the GPLv2 license,
the scheduling part remains proprietary, with a LICENSE file [2] stating:
"This is not Open Source software."
The researcher mentioned a plan to address the licensing issue, upstream
the patches, and step up as a maintainer, but there has been no further
communication since then.
Maintaining DCCP for a decade without any real users has become a burden.
Therefore, it's time to remove it.
Removing DCCP will also provide significant benefits to TCP. It allows
us to freely reorganize the layout of struct inet_connection_sock, which
is currently shared with DCCP, and optimize it to reduce the number of
cachelines accessed in the TCP fast path.
Note that we keep DCCP netfilter modules as requested. [3]
Link: https://lore.kernel.org/netdev/20230710182253.81446-1-kuniyu@amazon.com/T/#u #[0]
Link: https://github.com/telekom/mp-dccp #[1]
Link: https://github.com/telekom/mp-dccp/blob/mpdccp_v03_k5.10/net/dccp/non_gpl_scheduler/LICENSE #[2]
Link: https://lore.kernel.org/netdev/Z_VQ0KlCRkqYWXa-@calendula/ #[3]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paul Moore <paul@paul-moore.com> (LSM and SELinux)
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Link: https://patch.msgid.link/20250410023921.11307-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dccp: Add SIOCOUTQ IOCTL support (send buffer fill)2020-07-23T00:00:37+00:00Richard Sailerrichard_siegfried@systemli.org2020-07-20T16:06:14+00:00urn:sha1:749c08f8206cdf5cad15d557912898ce22aa55da
This adds support for the SIOCOUTQ IOCTL to get the send buffer fill
of a DCCP socket, like UDP and TCP sockets already have.
Regarding the used data field: DCCP uses per packet sequence numbers,
not per byte, so sequence numbers can't be used like in TCP. sk_wmem_queued
is not used by DCCP and always 0, even in test on highly congested paths.
Therefore this uses sk_wmem_alloc like in UDP.
Signed-off-by: Richard Sailer <richard_siegfried@systemli.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
docs: networking: convert dccp.txt to ReST2020-04-28T21:38:39+00:00Mauro Carvalho Chehabmchehab+huawei@kernel.org2020-04-27T22:01:28+00:00urn:sha1:33155bac6519f545137d9c46d2e59e5f8332dd50
- add SPDX header;
- adjust title markup;
- comment out text-only TOC from html/pdf output;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>