kernel/linux.git/Documentation/networking, branch v7.1.12

xsk: reclaim invalid Tx descriptors in ZC batch path

2026-08-09T18:26:28+00:00

[ Upstream commit 72f2b4516faf55d4dfac2414649d3cffa5fd2c5e ] The zero-copy Tx batch parser stops when it encounters an invalid descriptor. If this happens after one or more continuation descriptors, the Tx consumer can be advanced past fragments that are neither submitted to the driver nor returned to userspace through the completion ring. A similar problem occurs when a packet exceeds xdp_zc_max_segs. The descriptors consumed up to the limit are released without completion, and the remaining continuation descriptors can subsequently be interpreted as the beginning of another packet. Parse Tx batches in packet units and distinguish descriptors belonging to complete valid packets from descriptors consumed while draining an invalid or oversized packet. Return the former to the driver and append the latter to the CQ address area so userspace can reclaim their UMEM frames. Treat a standalone invalid descriptor as a one-descriptor reclaim-only packet. Advancing the Tx-ring consumer releases the ring slot, but does not by itself return ownership of the referenced UMEM frame to userspace. Once draining starts, continue until the packet's end-of-packet descriptor is consumed. Preserve the drain state on the socket when EOP has not yet been supplied, so draining can continue during a later call. Leave incomplete but otherwise valid packets on the Tx ring. Shared-UMEM pools using multi-buffer Tx also need packet-framed parsing. Walk their Tx sockets one packet at a time, preserving the existing per-socket fairness scheme, instead of using the legacy one-descriptor fallback. Keep that fallback for shared pools that do not use multi-buffer Tx. Since the drain state is maintained per socket and both the singular and shared paths can resume an interrupted drain, changing the socket list from singular to shared requires no special bind-time transition. CQ entries are positional, and drivers may complete only part of the Tx work returned by xsk_tx_peek_release_desc_batch(). Therefore, reclaim-only entries cannot be published immediately when earlier driver-visible descriptors are still outstanding. Track the number of driver-visible CQ entries preceding the reclaim entries. Let xsk_tx_completed() publish partial hardware Tx completions, and publish the reclaim entries only after every earlier Tx descriptor has completed. Complete a reclaim-only batch immediately when there is no driver-visible work in front of it, and prevent another Tx batch from being appended while reclaim entries remain pending. Also cap batch processing by the size of the pool's temporary descriptor array, as Tx rings belonging to sockets sharing a UMEM may have different sizes. This ensures that every invalid Tx descriptor consumed by the ZC batch path is either submitted to the driver as part of a valid packet or returned to userspace without violating CQ completion ordering. Reviewed-by: Jason Xing Signed-off-by: Maciej Fijalkowski Acked-by: Stanislav Fomichev Fixes: cf24f5a5feea ("xsk: add support for AF_XDP multi-buffer on Tx path") Link: https://patch.msgid.link/20260719135609.147823-5-maciej.fijalkowski@intel.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

bonding: 3ad: add lacp_strict configuration knob

2026-07-24T14:19:45+00:00

[ Upstream commit 32b0b8953343eaceaa816a9ead3b6bb66355c64e ] When an 802.3ad (LACP) bonding interface has no slaves in the collecting/distributing state, the bonding master still reports carrier as up as long as at least 'min_links' slaves have carrier. In this situation, only one slave is effectively used for TX/RX, while traffic received on other slaves is dropped. Upper-layer daemons therefore consider the interface operational, even though traffic may be blackholed if the lack of LACP negotiation means the partner is not ready to deal with traffic. Introduce a configuration knob to control this behavior. It allows the bonding master to assert carrier only when at least 'min_links' slaves are in Collecting_Distributing state. The default mode preserves the existing behavior. This patch only introduces the knob; its behavior is implemented in the subsequent commit. Fixes: 655f8919d549 ("bonding: add min links parameter to 802.3ad") Signed-off-by: Louis Scalbert Acked-by: Jay Vosburgh Link: https://patch.msgid.link/20260603150331.1919611-4-louis.scalbert@6wind.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ethernet: 3c509: Update documentation to match MAINTAINERS

2026-05-21T15:28:56+00:00

There has been apparently a single message only ever publicly posted by David Ruggiero, back in 2002, which added this documentation piece among others, and MAINTAINERS was never updated accordingly. It is therefore doubtful that his maintainer status has actually come into effect. Just replace the reference then so as not to confuse people. Signed-off-by: Maciej W. Rozycki Link: https://patch.msgid.link/alpine.DEB.2.21.2605201207380.1450@angie.orcam.me.uk Signed-off-by: Jakub Kicinski

Revert "drivers: net: 3com: 3c509: Remove this driver"

2026-05-21T15:28:56+00:00

This reverts commit 91f3a27ae9f66d81a5906461762c37c8a2bcab06. Contrary to the assumption stated with the original commit description this driver is in use and I'm going to maintain it for the foreseeable future. Signed-off-by: Maciej W. Rozycki Link: https://patch.msgid.link/alpine.DEB.2.21.2605201204260.1450@angie.orcam.me.uk Signed-off-by: Jakub Kicinski

Merge tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

2026-04-24T16:41:58+00:00

Pull networking deletions from Jakub Kicinski: "Delete some obsolete networking code Old code like amateur radio and NFC have long been a burden to core networking developers. syzbot loves to find bugs in BKL-era code, and noobs try to fix them. If we want to have a fighting chance of surviving the LLM-pocalypse this code needs to find a dedicated owner or get deleted. We've talked about these deletions multiple times in the past and every time someone wanted the code to stay. It is never very clear to me how many of those people actually use the code vs are just nostalgic to see it go. Amateur radio did have occasional users (or so I think) but most users switched to user space implementations since its all super slow stuff. Nobody stepped up to maintain the kernel code. We were lucky enough to find someone who wants to help with NFC so we're giving that a chance. Let's try to put the rest of this code behind us" * tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: drivers: net: 8390: wd80x3: Remove this driver drivers: net: 8390: ultra: Remove this driver drivers: net: 8390: AX88190: Remove this driver drivers: net: fujitsu: fmvj18x: Remove this driver drivers: net: smsc: smc91c92: Remove this driver drivers: net: smsc: smc9194: Remove this driver drivers: net: amd: nmclan: Remove this driver drivers: net: amd: lance: Remove this driver drivers: net: 3com: 3c589: Remove this driver drivers: net: 3com: 3c574: Remove this driver drivers: net: 3com: 3c515: Remove this driver drivers: net: 3com: 3c509: Remove this driver net: packetengines: remove obsolete yellowfin driver and vendor dir net: packetengines: remove obsolete hamachi driver net: remove unused ATM protocols and legacy ATM device drivers net: remove ax25 and amateur radio (hamradio) subsystem net: remove ISDN subsystem and Bluetooth CMTP caif: remove CAIF NETWORK LAYER

drivers: net: smsc: smc91c92: Remove this driver

2026-04-23T22:57:06+00:00

The smc91c92 was written by David A Hinds in 1999. It is an PCMCIA device, so unlikely to be used with modern kernels. Remove the Documentation as well, since it refers to kernel versions 1.2.13 until 1.3.71 and FTP sites which no longer exist. Signed-off-by: Andrew Lunn Link: https://patch.msgid.link/20260422-v7-0-0-net-next-driver-removal-v1-v2-8-08a5b59784d5@lunn.ch Signed-off-by: Jakub Kicinski

drivers: net: 3com: 3c509: Remove this driver

2026-04-23T22:56:43+00:00

The 3c509 was written by Donald Becker between 1993-2000. It is an ISA device, so unlikely to be used with modern kernels. Signed-off-by: Andrew Lunn Link: https://patch.msgid.link/20260422-v7-0-0-net-next-driver-removal-v1-v2-1-08a5b59784d5@lunn.ch Signed-off-by: Jakub Kicinski

net: remove unused ATM protocols and legacy ATM device drivers

2026-04-23T19:21:14+00:00

Remove the ATM protocol modules and PCI/SBUS ATM device drivers that are no longer in active use. The ATM core protocol stack, PPPoATM, BR2684, and USB DSL modem drivers (drivers/usb/atm/) are retained in-tree to maintain PPP over ATM (PPPoA) and PPPoE-over-BR2684 support for DSL connections. The Solos ADSL2+ PCI driver is also retained. Removed ATM protocol modules: - net/atm/clip.c - Classical IP over ATM (RFC 2225) - net/atm/lec.c - LAN Emulation Client (LANE) - net/atm/mpc.c, mpoa_caches.c, mpoa_proc.c - Multi-Protocol Over ATM Removed PCI/SBUS ATM device drivers (drivers/atm/): - adummy, atmtcp - software/testing ATM devices - eni - Efficient Networks ENI155P (OC-3, ~1995) - fore200e - FORE Systems 200E PCI/SBUS (OC-3, ~1999) - he - ForeRunner HE (OC-3/OC-12, ~2000) - idt77105 - IDT 77105 25 Mbps ATM PHY - idt77252 - IDT 77252 NICStAR II (OC-3, ~2000) - iphase - Interphase ATM PCI (OC-3/DS3/E3) - lanai - Efficient Networks Speedstream 3010 - nicstar - IDT 77201 NICStAR (155/25 Mbps, ~1999) - suni - PMC S/UNI SONET PHY library Also clean up references in: - net/bridge/ - remove ATM LANE hook (br_fdb_test_addr_hook, br_fdb_test_addr) - net/core/dev.c - remove br_fdb_test_addr_hook export - defconfig files - remove ATM driver config options The removed code is moved to an out-of-tree module package (mod-orphan). Acked-by: Andy Shevchenko Reviewed-by: Simon Horman Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20260422041846.2035118-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: remove ax25 and amateur radio (hamradio) subsystem

2026-04-23T17:24:02+00:00

Remove the amateur radio (AX.25, NET/ROM, ROSE) protocol implementation and all associated hamradio device drivers from the kernel tree. This set of protocols has long been a huge bug/syzbot magnet, and since nobody stepped up to help us deal with the influx of the AI-generated bug reports we need to move it out of tree to protect our sanity. The code is moved to an out-of-tree repo: https://github.com/linux-netdev/mod-orphan if it's cleaned up and reworked there we can accept it back. Minimal stub headers are kept for include/net/ax25.h (AX25_P_IP, AX25_ADDR_LEN, ax25_address) and include/net/rose.h (ROSE_ADDR_LEN) so that the conditional integration code in arp.c and tun.c continues to compile and work when the out-of-tree modules are loaded. Signed-off-by: Jakub Kicinski Acked-by: Greg Kroah-Hartman Acked-by: Stephen Hemminger Acked-by: Carlos Bilbao Reviewed-by: Simon Horman Reviewed-by: Kuniyuki Iwashima Acked-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/20260421021824.1293976-1-kuba@kernel.org Signed-off-by: Paolo Abeni

caif: remove CAIF NETWORK LAYER

2026-04-23T17:23:44+00:00

Remove CAIF (Communication CPU to Application CPU Interface), the ST-Ericsson modem protocol. The subsystem has been orphaned since 2013. The last meaningful changes from the maintainers were in March 2013: a8c7687bf216 ("caif_virtio: Check that vringh_config is not null") b2273be8d2df ("caif_virtio: Use vringh_notify_enable correctly") 0d2e1a2926b1 ("caif_virtio: Introduce caif over virtio") Not-so-coincidentally, according to "the Internet" ST-Ericsson officially shut down its modem joint venture in Aug 2013. If anyone is using this code please yell! In the 13 years since, the code has accumulated 200 non-merge commits, of which 71 were cross-tree API changes, 21 carried Fixes: tags, and the remaining ~110 were cleanups, doc conversions, treewide refactors, and one partial removal (caif_hsi, ca75bcf0a83b). We are still getting fixes to this code, in the last 10 days there were 3 reports on security@ about CAIF that I have been CCed on. UAPI constants (AF_CAIF, ARPHRD_CAIF, N_CAIF, VIRTIO_ID_CAIF) and the SELinux classmap entry are intentionally kept for ABI stability. Acked-by: Michael S. Tsirkin Acked-by: Greg Kroah-Hartman Reviewed-by: Linus Walleij Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260416182829.1440262-1-kuba@kernel.org Signed-off-by: Jakub Kicinski