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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+==============
+6pack Protocol
+==============
+
+This is the 6pack-mini-HOWTO, written by
+
+Andreas Könsgen DG3KQ
+
+:Internet: ajk@comnets.uni-bremen.de
+:AMPR-net: dg3kq@db0pra.ampr.org
+:AX.25: dg3kq@db0ach.#nrw.deu.eu
+
+Last update: April 7, 1998
+
+1. What is 6pack, and what are the advantages to KISS?
+======================================================
+
+6pack is a transmission protocol for data exchange between the PC and
+the TNC over a serial line. It can be used as an alternative to KISS.
+
+6pack has two major advantages:
+
+- The PC is given full control over the radio
+ channel. Special control data is exchanged between the PC and the TNC so
+ that the PC knows at any time if the TNC is receiving data, if a TNC
+ buffer underrun or overrun has occurred, if the PTT is
+ set and so on. This control data is processed at a higher priority than
+ normal data, so a data stream can be interrupted at any time to issue an
+ important event. This helps to improve the channel access and timing
+ algorithms as everything is computed in the PC. It would even be possible
+ to experiment with something completely different from the known CSMA and
+ DAMA channel access methods.
+ This kind of real-time control is especially important to supply several
+ TNCs that are connected between each other and the PC by a daisy chain
+ (however, this feature is not supported yet by the Linux 6pack driver).
+
+- Each packet transferred over the serial line is supplied with a checksum,
+ so it is easy to detect errors due to problems on the serial line.
+ Received packets that are corrupt are not passed on to the AX.25 layer.
+ Damaged packets that the TNC has received from the PC are not transmitted.
+
+More details about 6pack are described in the file 6pack.ps that is located
+in the doc directory of the AX.25 utilities package.
+
+2. Who has developed the 6pack protocol?
+========================================
+
+The 6pack protocol has been developed by Ekki Plicht DF4OR, Henning Rech
+DF9IC and Gunter Jost DK7WJ. A driver for 6pack, written by Gunter Jost and
+Matthias Welwarsky DG2FEF, comes along with the PC version of FlexNet.
+They have also written a firmware for TNCs to perform the 6pack
+protocol (see section 4 below).
+
+3. Where can I get the latest version of 6pack for LinuX?
+=========================================================
+
+At the moment, the 6pack stuff can obtained via anonymous ftp from
+db0bm.automation.fh-aachen.de. In the directory /incoming/dg3kq,
+there is a file named 6pack.tgz.
+
+4. Preparing the TNC for 6pack operation
+========================================
+
+To be able to use 6pack, a special firmware for the TNC is needed. The EPROM
+of a newly bought TNC does not contain 6pack, so you will have to
+program an EPROM yourself. The image file for 6pack EPROMs should be
+available on any packet radio box where PC/FlexNet can be found. The name of
+the file is 6pack.bin. This file is copyrighted and maintained by the FlexNet
+team. It can be used under the terms of the license that comes along
+with PC/FlexNet. Please do not ask me about the internals of this file as I
+don't know anything about it. I used a textual description of the 6pack
+protocol to program the Linux driver.
+
+TNCs contain a 64kByte EPROM, the lower half of which is used for
+the firmware/KISS. The upper half is either empty or is sometimes
+programmed with software called TAPR. In the latter case, the TNC
+is supplied with a DIP switch so you can easily change between the
+two systems. When programming a new EPROM, one of the systems is replaced
+by 6pack. It is useful to replace TAPR, as this software is rarely used
+nowadays. If your TNC is not equipped with the switch mentioned above, you
+can build in one yourself that switches over the highest address pin
+of the EPROM between HIGH and LOW level. After having inserted the new EPROM
+and switched to 6pack, apply power to the TNC for a first test. The connect
+and the status LED are lit for about a second if the firmware initialises
+the TNC correctly.
+
+5. Building and installing the 6pack driver
+===========================================
+
+The driver has been tested with kernel version 2.1.90. Use with older
+kernels may lead to a compilation error because the interface to a kernel
+function has been changed in the 2.1.8x kernels.
+
+How to turn on 6pack support:
+=============================
+
+- In the linux kernel configuration program, select the code maturity level
+ options menu and turn on the prompting for development drivers.
+
+- Select the amateur radio support menu and turn on the serial port 6pack
+ driver.
+
+- Compile and install the kernel and the modules.
+
+To use the driver, the kissattach program delivered with the AX.25 utilities
+has to be modified.
+
+- Do a cd to the directory that holds the kissattach sources. Edit the
+ kissattach.c file. At the top, insert the following lines::
+
+ #ifndef N_6PACK
+ #define N_6PACK (N_AX25+1)
+ #endif
+
+ Then find the line:
+
+ int disc = N_AX25;
+
+ and replace N_AX25 by N_6PACK.
+
+- Recompile kissattach. Rename it to spattach to avoid confusions.
+
+Installing the driver:
+----------------------
+
+- Do an insmod 6pack. Look at your /var/log/messages file to check if the
+ module has printed its initialization message.
+
+- Do a spattach as you would launch kissattach when starting a KISS port.
+ Check if the kernel prints the message '6pack: TNC found'.
+
+- From here, everything should work as if you were setting up a KISS port.
+ The only difference is that the network device that represents
+ the 6pack port is called sp instead of sl or ax. So, sp0 would be the
+ first 6pack port.
+
+Although the driver has been tested on various platforms, I still declare it
+ALPHA. BE CAREFUL! Sync your disks before insmoding the 6pack module
+and spattaching. Watch out if your computer behaves strangely. Read section
+6 of this file about known problems.
+
+Note that the connect and status LEDs of the TNC are controlled in a
+different way than they are when the TNC is used with PC/FlexNet. When using
+FlexNet, the connect LED is on if there is a connection; the status LED is
+on if there is data in the buffer of the PC's AX.25 engine that has to be
+transmitted. Under Linux, the 6pack layer is beyond the AX.25 layer,
+so the 6pack driver doesn't know anything about connects or data that
+has not yet been transmitted. Therefore the LEDs are controlled
+as they are in KISS mode: The connect LED is turned on if data is transferred
+from the PC to the TNC over the serial line, the status LED if data is
+sent to the PC.
+
+6. Known problems
+=================
+
+When testing the driver with 2.0.3x kernels and
+operating with data rates on the radio channel of 9600 Baud or higher,
+the driver may, on certain systems, sometimes print the message '6pack:
+bad checksum', which is due to data loss if the other station sends two
+or more subsequent packets. I have been told that this is due to a problem
+with the serial driver of 2.0.3x kernels. I don't know yet if the problem
+still exists with 2.1.x kernels, as I have heard that the serial driver
+code has been changed with 2.1.x.
+
+When shutting down the sp interface with ifconfig, the kernel crashes if
+there is still an AX.25 connection left over which an IP connection was
+running, even if that IP connection is already closed. The problem does not
+occur when there is a bare AX.25 connection still running. I don't know if
+this is a problem of the 6pack driver or something else in the kernel.
+
+The driver has been tested as a module, not yet as a kernel-builtin driver.
+
+The 6pack protocol supports daisy-chaining of TNCs in a token ring, which is
+connected to one serial port of the PC. This feature is not implemented
+and at least at the moment I won't be able to do it because I do not have
+the opportunity to build a TNC daisy-chain and test it.
+
+Some of the comments in the source code are inaccurate. They are left from
+the SLIP/KISS driver, from which the 6pack driver has been derived.
+I haven't modified or removed them yet -- sorry! The code itself needs
+some cleaning and optimizing. This will be done in a later release.
+
+If you encounter a bug or if you have a question or suggestion concerning the
+driver, feel free to mail me, using the addresses given at the beginning of
+this file.
+
+Have fun!
+
+Andreas