linux-stable.git/Documentation/networking, branch linux-6.12.y

bonding: add support for per-port LACP actor priority

2026-07-04T11:43:26+00:00

[ Upstream commit 6b6dc81ee7e8ca87c71a533e1d69cf96a4f1e986 ]

Introduce a new netlink attribute 'actor_port_prio' to allow setting
the LACP actor port priority on a per-slave basis. This extends the
existing bonding infrastructure to support more granular control over
LACP negotiations.

The priority value is embedded in LACPDU packets and will be used by
subsequent patches to influence aggregator selection policies.

Signed-off-by: Hangbin Liu 
Link: https://patch.msgid.link/20250902064501.360822-2-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Kevin Berry 
Signed-off-by: Greg Kroah-Hartman

net: bonding: add broadcast_neighbor option for 802.3ad

2026-07-04T11:43:25+00:00

[ Upstream commit ce7a381697cb3958ffe0b45e5028ac69444e9288 ]

Stacking technology is a type of technology used to expand ports on
Ethernet switches. It is widely used as a common access method in
large-scale Internet data center architectures. Years of practice
have proved that stacking technology has advantages and disadvantages
in high-reliability network architecture scenarios. For instance,
in stacking networking arch, conventional switch system upgrades
require multiple stacked devices to restart at the same time.
Therefore, it is inevitable that the business will be interrupted
for a while. It is for this reason that "no-stacking" in data centers
has become a trend. Additionally, when the stacking link connecting
the switches fails or is abnormal, the stack will split. Although it is
not common, it still happens in actual operation. The problem is that
after the split, it is equivalent to two switches with the same
configuration appearing in the network, causing network configuration
conflicts and ultimately interrupting the services carried by the
stacking system.

To improve network stability, "non-stacking" solutions have been
increasingly adopted, particularly by public cloud providers and
tech companies like Alibaba, Tencent, and Didi. "non-stacking" is
a method of mimicing switch stacking that convinces a LACP peer,
bonding in this case, connected to a set of "non-stacked" switches
that all of its ports are connected to a single switch
(i.e., LACP aggregator), as if those switches were stacked. This
enables the LACP peer's ports to aggregate together, and requires
(a) special switch configuration, described in the linked article,
and (b) modifications to the bonding 802.3ad (LACP) mode to send
all ARP/ND packets across all ports of the active aggregator.

Note that, with multiple aggregators, the current broadcast mode
logic will send only packets to the selected aggregator(s).

 +-----------+   +-----------+
 |  switch1  |   |  switch2  |
 +-----------+   +-----------+
         ^           ^
         |           |
      +-----------------+
      |   bond4 lacp    |
      +-----------------+
         |           |
         | NIC1      | NIC2
      +-----------------+
      |     server      |
      +-----------------+

- https://www.ruijie.com/fr-fr/support/tech-gallery/de-stack-data-center-network-architecture/

Cc: Jay Vosburgh 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Simon Horman 
Cc: Jonathan Corbet 
Cc: Andrew Lunn 
Cc: Steven Rostedt 
Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Cc: Nikolay Aleksandrov 
Signed-off-by: Tonghao Zhang 
Signed-off-by: Zengbing Tu 
Link: https://patch.msgid.link/84d0a044514157bb856a10b6d03a1028c4883561.1751031306.git.tonghao@bamaicloud.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Kevin Berry 
Signed-off-by: Greg Kroah-Hartman

netconsole: allow selection of egress interface via MAC address

2026-05-23T11:04:54+00:00

[ Upstream commit f8a10bed32f5fbede13a5f22fdc4ab8740ea213a ]

Currently, netconsole has two methods of configuration - module
parameter and configfs. The former interface allows for netconsole
activation earlier during boot (by specifying the module parameter on
the kernel command line), so it is preferred for debugging issues which
arise before userspace is up/the configfs interface can be used. The
module parameter syntax requires specifying the egress interface name.
This requirement makes it hard to use for a couple reasons:
- The egress interface name can be hard or impossible to predict. For
  example, installing a new network card in a system can change the
  interface names assigned by the kernel.
- When constructing the module parameter, one may have trouble
  determining the original (kernel-assigned) name of the interface
  (which is the name that should be given to netconsole) if some stable
  interface naming scheme is in effect. A human can usually look at
  kernel logs to determine the original name, but this is very painful
  if automation is constructing the parameter.

For these reasons, allow selection of the egress interface via MAC
address when configuring netconsole using the module parameter. Update
the netconsole documentation with an example of the new syntax.
Selection of egress interface by MAC address via configfs is far less
interesting (since when this interface can be used, one should be able
to easily convert between MAC address and interface name), so it is left
unimplemented.

Signed-off-by: Uday Shankar 
Reviewed-by: Breno Leitao 
Tested-by: Breno Leitao 
Reviewed-by: Simon Horman 
Link: https://patch.msgid.link/20250312-netconsole-v6-2-3437933e79b8@purestorage.com
Signed-off-by: Paolo Abeni 
Stable-dep-of: 3bc179bc7146 ("netpoll: fix IPv6 local-address corruption")
Signed-off-by: Sasha Levin

doc: fix seg6_flowlabel path

2025-10-23T14:20:29+00:00

[ Upstream commit 0b4b77eff5f8cd9be062783a1c1e198d46d0a753 ]

This sysctl is not per interface; it's global per netns.

Fixes: 292ecd9f5a94 ("doc: move seg6_flowlabel to seg6-sysctl.rst")
Reported-by: Philippe Guibert 
Signed-off-by: Nicolas Dichtel 
Reviewed-by: Simon Horman 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

docs: networking: can: change bcm_msg_head frames member to support flexible array

2025-09-19T14:35:49+00:00

[ Upstream commit 641427d5bf90af0625081bf27555418b101274cd ]

The documentation of the 'bcm_msg_head' struct does not match how
it is defined in 'bcm.h'. Changed the frames member to a flexible array,
matching the definition in the header file.

See commit 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with
flexible-array members")

Signed-off-by: Alex Tran 
Acked-by: Oliver Hartkopp 
Link: https://patch.msgid.link/20250904031709.1426895-1-alex.t.tran@gmail.com
Fixes: 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217783
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Sasha Levin

mptcp: disable add_addr retransmission when timeout is 0

2025-08-28T14:31:07+00:00

commit f5ce0714623cffd00bf2a83e890d09c609b7f50a upstream.

When add_addr_timeout was set to 0, this caused the ADD_ADDR to be
retransmitted immediately, which looks like a buggy behaviour. Instead,
interpret 0 as "no retransmissions needed".

The documentation is updated to explicitly state that setting the timeout
to 0 disables retransmission.

Fixes: 93f323b9cccc ("mptcp: add a new sysctl add_addr_timeout")
Cc: stable@vger.kernel.org
Suggested-by: Matthieu Baerts 
Signed-off-by: Geliang Tang 
Reviewed-by: Matthieu Baerts (NGI0) 
Signed-off-by: Matthieu Baerts (NGI0) 
Link: https://patch.msgid.link/20250815-net-mptcp-misc-fixes-6-17-rc2-v1-5-521fe9957892@kernel.org
Signed-off-by: Jakub Kicinski 
[ Before commit e4c28e3d5c09 ("mptcp: pm: move generic PM helpers to
  pm.c"), mptcp_pm_alloc_anno_list() was in pm_netlink.c. The same patch
  can be applied there without conflicts. ]
Signed-off-by: Matthieu Baerts (NGI0) 
Signed-off-by: Greg Kroah-Hartman

strparser: Add read_sock callback

2025-02-27T12:30:19+00:00

[ Upstream commit 0532a79efd68a4d9686b0385e4993af4b130ff82 ]

Added a new read_sock handler, allowing users to customize read operations
instead of relying on the native socket's read_sock.

Signed-off-by: Jiayuan Chen 
Signed-off-by: Martin KaFai Lau 
Reviewed-by: Jakub Sitnicki 
Acked-by: John Fastabend 
Link: https://patch.msgid.link/20250122100917.49845-2-mrpre@163.com
Stable-dep-of: 36b62df5683c ("bpf: Fix wrong copied_seq calculation")
Signed-off-by: Sasha Levin

Documentation/networking: fix basic node example document ISO 15765-2

2025-02-21T13:01:16+00:00

[ Upstream commit d0b197b6505fe3788860fc2a81b3ce53cbecc69c ]

In the current struct sockaddr_can tp is member of can_addr. tp is not
member of struct sockaddr_can.

Signed-off-by: Reyders Morales 
Reviewed-by: Simon Horman 
Acked-by: Oliver Hartkopp 
Link: https://patch.msgid.link/20250203224720.42530-1-reyders1@gmail.com
Fixes: 67711e04254c ("Documentation: networking: document ISO 15765-2")
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Sasha Levin

Documentation: networking: Add a caveat to nexthop_compat_mode sysctl

2024-12-19T17:13:16+00:00

[ Upstream commit bbe4b41259a3e255a16d795486d331c1670b4e75 ]

net.ipv4.nexthop_compat_mode was added when nexthop objects were added to
provide the view of nexthop objects through the usual lens of the route
UAPI. As nexthop objects evolved, the information provided through this
lens became incomplete. For example, details of resilient nexthop groups
are obviously omitted.

Now that 16-bit nexthop group weights are a thing, the 8-bit UAPI cannot
convey the >8-bit weight accurately. Instead of inventing workarounds for
an obsolete interface, just document the expectations of inaccuracy.

Fixes: b72a6a7ab957 ("net: nexthop: Increase weight to u16")
Signed-off-by: Petr Machata 
Reviewed-by: Ido Schimmel 
Reviewed-by: David Ahern 
Link: https://patch.msgid.link/b575e32399ccacd09079b2a218255164535123bd.1733740749.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net: clarify SO_DEVMEM_DONTNEED behavior in documentation

2024-11-12T02:11:46+00:00

Document new behavior when the number of frags passed is too big.

Signed-off-by: Mina Almasry 
Link: https://patch.msgid.link/20241107210331.3044434-2-almasrymina@google.com
Signed-off-by: Jakub Kicinski