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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
+
+=======================================
+Linux wireless regulatory documentation
+=======================================
+
+This document gives a brief review over how the Linux wireless
+regulatory infrastructure works.
+
+More up to date information can be obtained at the project's web page:
+
+https://wireless.wiki.kernel.org/en/developers/Regulatory
+
+Keeping regulatory domains in userspace
+---------------------------------------
+
+Due to the dynamic nature of regulatory domains we keep them
+in userspace and provide a framework for userspace to upload
+to the kernel one regulatory domain to be used as the central
+core regulatory domain all wireless devices should adhere to.
+
+How to get regulatory domains to the kernel
+-------------------------------------------
+
+When the regulatory domain is first set up, the kernel will request a
+database file (regulatory.db) containing all the regulatory rules. It
+will then use that database when it needs to look up the rules for a
+given country.
+
+How to get regulatory domains to the kernel (old CRDA solution)
+---------------------------------------------------------------
+
+Userspace gets a regulatory domain in the kernel by having
+a userspace agent build it and send it via nl80211. Only
+expected regulatory domains will be respected by the kernel.
+
+A currently available userspace agent which can accomplish this
+is CRDA - central regulatory domain agent. Its documented here:
+
+https://wireless.wiki.kernel.org/en/developers/Regulatory/CRDA
+
+Essentially the kernel will send a udev event when it knows
+it needs a new regulatory domain. A udev rule can be put in place
+to trigger crda to send the respective regulatory domain for a
+specific ISO/IEC 3166 alpha2.
+
+Below is an example udev rule which can be used:
+
+# Example file, should be put in /etc/udev/rules.d/regulatory.rules
+KERNEL=="regulatory*", ACTION=="change", SUBSYSTEM=="platform", RUN+="/sbin/crda"
+
+The alpha2 is passed as an environment variable under the variable COUNTRY.
+
+Who asks for regulatory domains?
+--------------------------------
+
+* Users
+
+Users can use iw:
+
+https://wireless.wiki.kernel.org/en/users/Documentation/iw
+
+An example::
+
+ # set regulatory domain to "Costa Rica"
+ iw reg set CR
+
+This will request the kernel to set the regulatory domain to
+the specified alpha2. The kernel in turn will then ask userspace
+to provide a regulatory domain for the alpha2 specified by the user
+by sending a uevent.
+
+* Wireless subsystems for Country Information elements
+
+The kernel will send a uevent to inform userspace a new
+regulatory domain is required. More on this to be added
+as its integration is added.
+
+* Drivers
+
+If drivers determine they need a specific regulatory domain
+set they can inform the wireless core using regulatory_hint().
+They have two options -- they either provide an alpha2 so that
+crda can provide back a regulatory domain for that country or
+they can build their own regulatory domain based on internal
+custom knowledge so the wireless core can respect it.
+
+*Most* drivers will rely on the first mechanism of providing a
+regulatory hint with an alpha2. For these drivers there is an additional
+check that can be used to ensure compliance based on custom EEPROM
+regulatory data. This additional check can be used by drivers by
+registering on its struct wiphy a reg_notifier() callback. This notifier
+is called when the core's regulatory domain has been changed. The driver
+can use this to review the changes made and also review who made them
+(driver, user, country IE) and determine what to allow based on its
+internal EEPROM data. Devices drivers wishing to be capable of world
+roaming should use this callback. More on world roaming will be
+added to this document when its support is enabled.
+
+Device drivers who provide their own built regulatory domain
+do not need a callback as the channels registered by them are
+the only ones that will be allowed and therefore *additional*
+channels cannot be enabled.
+
+Example code - drivers hinting an alpha2:
+------------------------------------------
+
+This example comes from the zd1211rw device driver. You can start
+by having a mapping of your device's EEPROM country/regulatory
+domain value to a specific alpha2 as follows::
+
+ static struct zd_reg_alpha2_map reg_alpha2_map[] = {
+ { ZD_REGDOMAIN_FCC, "US" },
+ { ZD_REGDOMAIN_IC, "CA" },
+ { ZD_REGDOMAIN_ETSI, "DE" }, /* Generic ETSI, use most restrictive */
+ { ZD_REGDOMAIN_JAPAN, "JP" },
+ { ZD_REGDOMAIN_JAPAN_ADD, "JP" },
+ { ZD_REGDOMAIN_SPAIN, "ES" },
+ { ZD_REGDOMAIN_FRANCE, "FR" },
+
+Then you can define a routine to map your read EEPROM value to an alpha2,
+as follows::
+
+ static int zd_reg2alpha2(u8 regdomain, char *alpha2)
+ {
+ unsigned int i;
+ struct zd_reg_alpha2_map *reg_map;
+ for (i = 0; i < ARRAY_SIZE(reg_alpha2_map); i++) {
+ reg_map = &reg_alpha2_map[i];
+ if (regdomain == reg_map->reg) {
+ alpha2[0] = reg_map->alpha2[0];
+ alpha2[1] = reg_map->alpha2[1];
+ return 0;
+ }
+ }
+ return 1;
+ }
+
+Lastly, you can then hint to the core of your discovered alpha2, if a match
+was found. You need to do this after you have registered your wiphy. You
+are expected to do this during initialization.
+
+::
+
+ r = zd_reg2alpha2(mac->regdomain, alpha2);
+ if (!r)
+ regulatory_hint(hw->wiphy, alpha2);
+
+Example code - drivers providing a built in regulatory domain:
+--------------------------------------------------------------
+
+[NOTE: This API is not currently available, it can be added when required]
+
+If you have regulatory information you can obtain from your
+driver and you *need* to use this we let you build a regulatory domain
+structure and pass it to the wireless core. To do this you should
+kmalloc() a structure big enough to hold your regulatory domain
+structure and you should then fill it with your data. Finally you simply
+call regulatory_hint() with the regulatory domain structure in it.
+
+Below is a simple example, with a regulatory domain cached using the stack.
+Your implementation may vary (read EEPROM cache instead, for example).
+
+Example cache of some regulatory domain::
+
+ struct ieee80211_regdomain mydriver_jp_regdom = {
+ .n_reg_rules = 3,
+ .alpha2 = "JP",
+ //.alpha2 = "99", /* If I have no alpha2 to map it to */
+ .reg_rules = {
+ /* IEEE 802.11b/g, channels 1..14 */
+ REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
+ /* IEEE 802.11a, channels 34..48 */
+ REG_RULE(5170-10, 5240+10, 40, 6, 20,
+ NL80211_RRF_NO_IR),
+ /* IEEE 802.11a, channels 52..64 */
+ REG_RULE(5260-10, 5320+10, 40, 6, 20,
+ NL80211_RRF_NO_IR|
+ NL80211_RRF_DFS),
+ }
+ };
+
+Then in some part of your code after your wiphy has been registered::
+
+ struct ieee80211_regdomain *rd;
+ int size_of_regd;
+ int num_rules = mydriver_jp_regdom.n_reg_rules;
+ unsigned int i;
+
+ size_of_regd = sizeof(struct ieee80211_regdomain) +
+ (num_rules * sizeof(struct ieee80211_reg_rule));
+
+ rd = kzalloc(size_of_regd, GFP_KERNEL);
+ if (!rd)
+ return -ENOMEM;
+
+ memcpy(rd, &mydriver_jp_regdom, sizeof(struct ieee80211_regdomain));
+
+ for (i=0; i < num_rules; i++)
+ memcpy(&rd->reg_rules[i],
+ &mydriver_jp_regdom.reg_rules[i],
+ sizeof(struct ieee80211_reg_rule));
+ regulatory_struct_hint(rd);
+
+Statically compiled regulatory database
+---------------------------------------
+
+When a database should be fixed into the kernel, it can be provided as a
+firmware file at build time that is then linked into the kernel.