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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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+Deterministic Automata
+======================
+
+Formally, a deterministic automaton, denoted by G, is defined as a quintuple:
+
+ *G* = { *X*, *E*, *f*, x\ :subscript:`0`, X\ :subscript:`m` }
+
+where:
+
+- *X* is the set of states;
+- *E* is the finite set of events;
+- x\ :subscript:`0` is the initial state;
+- X\ :subscript:`m` (subset of *X*) is the set of marked (or final) states.
+- *f* : *X* x *E* -> *X* $ is the transition function. It defines the state
+ transition in the occurrence of an event from *E* in the state *X*. In the
+ special case of deterministic automata, the occurrence of the event in *E*
+ in a state in *X* has a deterministic next state from *X*.
+
+For example, a given automaton named 'wip' (wakeup in preemptive) can
+be defined as:
+
+- *X* = { ``preemptive``, ``non_preemptive``}
+- *E* = { ``preempt_enable``, ``preempt_disable``, ``sched_waking``}
+- x\ :subscript:`0` = ``preemptive``
+- X\ :subscript:`m` = {``preemptive``}
+- *f* =
+ - *f*\ (``preemptive``, ``preempt_disable``) = ``non_preemptive``
+ - *f*\ (``non_preemptive``, ``sched_waking``) = ``non_preemptive``
+ - *f*\ (``non_preemptive``, ``preempt_enable``) = ``preemptive``
+
+One of the benefits of this formal definition is that it can be presented
+in multiple formats. For example, using a *graphical representation*, using
+vertices (nodes) and edges, which is very intuitive for *operating system*
+practitioners, without any loss.
+
+The previous 'wip' automaton can also be represented as::
+
+ preempt_enable
+ +---------------------------------+
+ v |
+ #============# preempt_disable +------------------+
+ --> H preemptive H -----------------> | non_preemptive |
+ #============# +------------------+
+ ^ |
+ | sched_waking |
+ +--------------+
+
+Deterministic Automaton in C
+----------------------------
+
+In the paper "Efficient formal verification for the Linux kernel",
+the authors present a simple way to represent an automaton in C that can
+be used as regular code in the Linux kernel.
+
+For example, the 'wip' automata can be presented as (augmented with comments)::
+
+ /* enum representation of X (set of states) to be used as index */
+ enum states {
+ preemptive = 0,
+ non_preemptive,
+ state_max
+ };
+
+ #define INVALID_STATE state_max
+
+ /* enum representation of E (set of events) to be used as index */
+ enum events {
+ preempt_disable = 0,
+ preempt_enable,
+ sched_waking,
+ event_max
+ };
+
+ struct automaton {
+ char *state_names[state_max]; // X: the set of states
+ char *event_names[event_max]; // E: the finite set of events
+ unsigned char function[state_max][event_max]; // f: transition function
+ unsigned char initial_state; // x_0: the initial state
+ bool final_states[state_max]; // X_m: the set of marked states
+ };
+
+ struct automaton aut = {
+ .state_names = {
+ "preemptive",
+ "non_preemptive"
+ },
+ .event_names = {
+ "preempt_disable",
+ "preempt_enable",
+ "sched_waking"
+ },
+ .function = {
+ { non_preemptive, INVALID_STATE, INVALID_STATE },
+ { INVALID_STATE, preemptive, non_preemptive },
+ },
+ .initial_state = preemptive,
+ .final_states = { 1, 0 },
+ };
+
+The *transition function* is represented as a matrix of states (lines) and
+events (columns), and so the function *f* : *X* x *E* -> *X* can be solved
+in O(1). For example::
+
+ next_state = automaton_wip.function[curr_state][event];
+
+Graphviz .dot format
+--------------------
+
+The Graphviz open-source tool can produce the graphical representation
+of an automaton using the (textual) DOT language as the source code.
+The DOT format is widely used and can be converted to many other formats.
+
+For example, this is the 'wip' model in DOT::
+
+ digraph state_automaton {
+ {node [shape = circle] "non_preemptive"};
+ {node [shape = plaintext, style=invis, label=""] "__init_preemptive"};
+ {node [shape = doublecircle] "preemptive"};
+ {node [shape = circle] "preemptive"};
+ "__init_preemptive" -> "preemptive";
+ "non_preemptive" [label = "non_preemptive"];
+ "non_preemptive" -> "non_preemptive" [ label = "sched_waking" ];
+ "non_preemptive" -> "preemptive" [ label = "preempt_enable" ];
+ "preemptive" [label = "preemptive"];
+ "preemptive" -> "non_preemptive" [ label = "preempt_disable" ];
+ { rank = min ;
+ "__init_preemptive";
+ "preemptive";
+ }
+ }
+
+This DOT format can be transformed into a bitmap or vectorial image
+using the dot utility, or into an ASCII art using graph-easy. For
+instance::
+
+ $ dot -Tsvg -o wip.svg wip.dot
+ $ graph-easy wip.dot > wip.txt
+
+dot2c
+-----
+
+dot2c is a utility that can parse a .dot file containing an automaton as
+in the example above and automatically convert it to the C representation
+presented in [3].
+
+For example, having the previous 'wip' model into a file named 'wip.dot',
+the following command will transform the .dot file into the C
+representation (previously shown) in the 'wip.h' file::
+
+ $ dot2c wip.dot > wip.h
+
+The 'wip.h' content is the code sample in section 'Deterministic Automaton
+in C'.
+
+Remarks
+-------
+
+The automata formalism allows modeling discrete event systems (DES) in
+multiple formats, suitable for different applications/users.
+
+For example, the formal description using set theory is better suitable
+for automata operations, while the graphical format for human interpretation;
+and computer languages for machine execution.
+
+References
+----------
+
+Many textbooks cover automata formalism. For a brief introduction see::
+
+ O'Regan, Gerard. Concise guide to software engineering. Springer,
+ Cham, 2017.
+
+For a detailed description, including operations, and application on Discrete
+Event Systems (DES), see::
+
+ Cassandras, Christos G., and Stephane Lafortune, eds. Introduction to discrete
+ event systems. Boston, MA: Springer US, 2008.
+
+For the C representation in kernel, see::
+
+ De Oliveira, Daniel Bristot; Cucinotta, Tommaso; De Oliveira, Romulo
+ Silva. Efficient formal verification for the Linux kernel. In:
+ International Conference on Software Engineering and Formal Methods.
+ Springer, Cham, 2019. p. 315-332.