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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
+
+===========
+IPvs-sysctl
+===========
+
+/proc/sys/net/ipv4/vs/* Variables:
+==================================
+
+am_droprate - INTEGER
+ default 10
+
+ It sets the always mode drop rate, which is used in the mode 3
+ of the drop_rate defense.
+
+amemthresh - INTEGER
+ default 1024
+
+ It sets the available memory threshold (in pages), which is
+ used in the automatic modes of defense. When there is no
+ enough available memory, the respective strategy will be
+ enabled and the variable is automatically set to 2, otherwise
+ the strategy is disabled and the variable is set to 1.
+
+backup_only - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ If set, disable the director function while the server is
+ in backup mode to avoid packet loops for DR/TUN methods.
+
+conn_reuse_mode - INTEGER
+ 1 - default
+
+ Controls how ipvs will deal with connections that are detected
+ port reuse. It is a bitmap, with the values being:
+
+ 0: disable any special handling on port reuse. The new
+ connection will be delivered to the same real server that was
+ servicing the previous connection.
+
+ bit 1: enable rescheduling of new connections when it is safe.
+ That is, whenever expire_nodest_conn and for TCP sockets, when
+ the connection is in TIME_WAIT state (which is only possible if
+ you use NAT mode).
+
+ bit 2: it is bit 1 plus, for TCP connections, when connections
+ are in FIN_WAIT state, as this is the last state seen by load
+ balancer in Direct Routing mode. This bit helps on adding new
+ real servers to a very busy cluster.
+
+conntrack - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ If set, maintain connection tracking entries for
+ connections handled by IPVS.
+
+ This should be enabled if connections handled by IPVS are to be
+ also handled by stateful firewall rules. That is, iptables rules
+ that make use of connection tracking. It is a performance
+ optimisation to disable this setting otherwise.
+
+ Connections handled by the IPVS FTP application module
+ will have connection tracking entries regardless of this setting.
+
+ Only available when IPVS is compiled with CONFIG_IP_VS_NFCT enabled.
+
+cache_bypass - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ If it is enabled, forward packets to the original destination
+ directly when no cache server is available and destination
+ address is not local (iph->daddr is RTN_UNICAST). It is mostly
+ used in transparent web cache cluster.
+
+debug_level - INTEGER
+ - 0 - transmission error messages (default)
+ - 1 - non-fatal error messages
+ - 2 - configuration
+ - 3 - destination trash
+ - 4 - drop entry
+ - 5 - service lookup
+ - 6 - scheduling
+ - 7 - connection new/expire, lookup and synchronization
+ - 8 - state transition
+ - 9 - binding destination, template checks and applications
+ - 10 - IPVS packet transmission
+ - 11 - IPVS packet handling (ip_vs_in/ip_vs_out)
+ - 12 or more - packet traversal
+
+ Only available when IPVS is compiled with CONFIG_IP_VS_DEBUG enabled.
+
+ Higher debugging levels include the messages for lower debugging
+ levels, so setting debug level 2, includes level 0, 1 and 2
+ messages. Thus, logging becomes more and more verbose the higher
+ the level.
+
+drop_entry - INTEGER
+ - 0 - disabled (default)
+
+ The drop_entry defense is to randomly drop entries in the
+ connection hash table, just in order to collect back some
+ memory for new connections. In the current code, the
+ drop_entry procedure can be activated every second, then it
+ randomly scans 1/32 of the whole and drops entries that are in
+ the SYN-RECV/SYNACK state, which should be effective against
+ syn-flooding attack.
+
+ The valid values of drop_entry are from 0 to 3, where 0 means
+ that this strategy is always disabled, 1 and 2 mean automatic
+ modes (when there is no enough available memory, the strategy
+ is enabled and the variable is automatically set to 2,
+ otherwise the strategy is disabled and the variable is set to
+ 1), and 3 means that the strategy is always enabled.
+
+drop_packet - INTEGER
+ - 0 - disabled (default)
+
+ The drop_packet defense is designed to drop 1/rate packets
+ before forwarding them to real servers. If the rate is 1, then
+ drop all the incoming packets.
+
+ The value definition is the same as that of the drop_entry. In
+ the automatic mode, the rate is determined by the follow
+ formula: rate = amemthresh / (amemthresh - available_memory)
+ when available memory is less than the available memory
+ threshold. When the mode 3 is set, the always mode drop rate
+ is controlled by the /proc/sys/net/ipv4/vs/am_droprate.
+
+est_cpulist - CPULIST
+ Allowed CPUs for estimation kthreads
+
+ Syntax: standard cpulist format
+ empty list - stop kthread tasks and estimation
+ default - the system's housekeeping CPUs for kthreads
+
+ Example:
+ "all": all possible CPUs
+ "0-N": all possible CPUs, N denotes last CPU number
+ "0,1-N:1/2": first and all CPUs with odd number
+ "": empty list
+
+est_nice - INTEGER
+ default 0
+ Valid range: -20 (more favorable) .. 19 (less favorable)
+
+ Niceness value to use for the estimation kthreads (scheduling
+ priority)
+
+expire_nodest_conn - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ The default value is 0, the load balancer will silently drop
+ packets when its destination server is not available. It may
+ be useful, when user-space monitoring program deletes the
+ destination server (because of server overload or wrong
+ detection) and add back the server later, and the connections
+ to the server can continue.
+
+ If this feature is enabled, the load balancer will expire the
+ connection immediately when a packet arrives and its
+ destination server is not available, then the client program
+ will be notified that the connection is closed. This is
+ equivalent to the feature some people requires to flush
+ connections when its destination is not available.
+
+expire_quiescent_template - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ When set to a non-zero value, the load balancer will expire
+ persistent templates when the destination server is quiescent.
+ This may be useful, when a user makes a destination server
+ quiescent by setting its weight to 0 and it is desired that
+ subsequent otherwise persistent connections are sent to a
+ different destination server. By default new persistent
+ connections are allowed to quiescent destination servers.
+
+ If this feature is enabled, the load balancer will expire the
+ persistence template if it is to be used to schedule a new
+ connection and the destination server is quiescent.
+
+ignore_tunneled - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ If set, ipvs will set the ipvs_property on all packets which are of
+ unrecognized protocols. This prevents us from routing tunneled
+ protocols like ipip, which is useful to prevent rescheduling
+ packets that have been tunneled to the ipvs host (i.e. to prevent
+ ipvs routing loops when ipvs is also acting as a real server).
+
+nat_icmp_send - BOOLEAN
+ - 0 - disabled (default)
+ - not 0 - enabled
+
+ It controls sending icmp error messages (ICMP_DEST_UNREACH)
+ for VS/NAT when the load balancer receives packets from real
+ servers but the connection entries don't exist.
+
+pmtu_disc - BOOLEAN
+ - 0 - disabled
+ - not 0 - enabled (default)
+
+ By default, reject with FRAG_NEEDED all DF packets that exceed
+ the PMTU, irrespective of the forwarding method. For TUN method
+ the flag can be disabled to fragment such packets.
+
+secure_tcp - INTEGER
+ - 0 - disabled (default)
+
+ The secure_tcp defense is to use a more complicated TCP state
+ transition table. For VS/NAT, it also delays entering the
+ TCP ESTABLISHED state until the three way handshake is completed.
+
+ The value definition is the same as that of drop_entry and
+ drop_packet.
+
+sync_threshold - vector of 2 INTEGERs: sync_threshold, sync_period
+ default 3 50
+
+ It sets synchronization threshold, which is the minimum number
+ of incoming packets that a connection needs to receive before
+ the connection will be synchronized. A connection will be
+ synchronized, every time the number of its incoming packets
+ modulus sync_period equals the threshold. The range of the
+ threshold is from 0 to sync_period.
+
+ When sync_period and sync_refresh_period are 0, send sync only
+ for state changes or only once when pkts matches sync_threshold
+
+sync_refresh_period - UNSIGNED INTEGER
+ default 0
+
+ In seconds, difference in reported connection timer that triggers
+ new sync message. It can be used to avoid sync messages for the
+ specified period (or half of the connection timeout if it is lower)
+ if connection state is not changed since last sync.
+
+ This is useful for normal connections with high traffic to reduce
+ sync rate. Additionally, retry sync_retries times with period of
+ sync_refresh_period/8.
+
+sync_retries - INTEGER
+ default 0
+
+ Defines sync retries with period of sync_refresh_period/8. Useful
+ to protect against loss of sync messages. The range of the
+ sync_retries is from 0 to 3.
+
+sync_qlen_max - UNSIGNED LONG
+
+ Hard limit for queued sync messages that are not sent yet. It
+ defaults to 1/32 of the memory pages but actually represents
+ number of messages. It will protect us from allocating large
+ parts of memory when the sending rate is lower than the queuing
+ rate.
+
+sync_sock_size - INTEGER
+ default 0
+
+ Configuration of SNDBUF (master) or RCVBUF (slave) socket limit.
+ Default value is 0 (preserve system defaults).
+
+sync_ports - INTEGER
+ default 1
+
+ The number of threads that master and backup servers can use for
+ sync traffic. Every thread will use single UDP port, thread 0 will
+ use the default port 8848 while last thread will use port
+ 8848+sync_ports-1.
+
+snat_reroute - BOOLEAN
+ - 0 - disabled
+ - not 0 - enabled (default)
+
+ If enabled, recalculate the route of SNATed packets from
+ realservers so that they are routed as if they originate from the
+ director. Otherwise they are routed as if they are forwarded by the
+ director.
+
+ If policy routing is in effect then it is possible that the route
+ of a packet originating from a director is routed differently to a
+ packet being forwarded by the director.
+
+ If policy routing is not in effect then the recalculated route will
+ always be the same as the original route so it is an optimisation
+ to disable snat_reroute and avoid the recalculation.
+
+sync_persist_mode - INTEGER
+ default 0
+
+ Controls the synchronisation of connections when using persistence
+
+ 0: All types of connections are synchronised
+
+ 1: Attempt to reduce the synchronisation traffic depending on
+ the connection type. For persistent services avoid synchronisation
+ for normal connections, do it only for persistence templates.
+ In such case, for TCP and SCTP it may need enabling sloppy_tcp and
+ sloppy_sctp flags on backup servers. For non-persistent services
+ such optimization is not applied, mode 0 is assumed.
+
+sync_version - INTEGER
+ default 1
+
+ The version of the synchronisation protocol used when sending
+ synchronisation messages.
+
+ 0 selects the original synchronisation protocol (version 0). This
+ should be used when sending synchronisation messages to a legacy
+ system that only understands the original synchronisation protocol.
+
+ 1 selects the current synchronisation protocol (version 1). This
+ should be used where possible.
+
+ Kernels with this sync_version entry are able to receive messages
+ of both version 1 and version 2 of the synchronisation protocol.
+
+run_estimation - BOOLEAN
+ 0 - disabled
+ not 0 - enabled (default)
+
+ If disabled, the estimation will be suspended and kthread tasks
+ stopped.
+
+ You can always re-enable estimation by setting this value to 1.
+ But be careful, the first estimation after re-enable is not
+ accurate.