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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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+.. _elf_hwcaps_index:
+
+================
+ARM64 ELF hwcaps
+================
+
+This document describes the usage and semantics of the arm64 ELF hwcaps.
+
+
+1. Introduction
+---------------
+
+Some hardware or software features are only available on some CPU
+implementations, and/or with certain kernel configurations, but have no
+architected discovery mechanism available to userspace code at EL0. The
+kernel exposes the presence of these features to userspace through a set
+of flags called hwcaps, exposed in the auxiliary vector.
+
+Userspace software can test for features by acquiring the AT_HWCAP or
+AT_HWCAP2 entry of the auxiliary vector, and testing whether the relevant
+flags are set, e.g.::
+
+ bool floating_point_is_present(void)
+ {
+ unsigned long hwcaps = getauxval(AT_HWCAP);
+ if (hwcaps & HWCAP_FP)
+ return true;
+
+ return false;
+ }
+
+Where software relies on a feature described by a hwcap, it should check
+the relevant hwcap flag to verify that the feature is present before
+attempting to make use of the feature.
+
+Features cannot be probed reliably through other means. When a feature
+is not available, attempting to use it may result in unpredictable
+behaviour, and is not guaranteed to result in any reliable indication
+that the feature is unavailable, such as a SIGILL.
+
+
+2. Interpretation of hwcaps
+---------------------------
+
+The majority of hwcaps are intended to indicate the presence of features
+which are described by architected ID registers inaccessible to
+userspace code at EL0. These hwcaps are defined in terms of ID register
+fields, and should be interpreted with reference to the definition of
+these fields in the ARM Architecture Reference Manual (ARM ARM).
+
+Such hwcaps are described below in the form::
+
+ Functionality implied by idreg.field == val.
+
+Such hwcaps indicate the availability of functionality that the ARM ARM
+defines as being present when idreg.field has value val, but do not
+indicate that idreg.field is precisely equal to val, nor do they
+indicate the absence of functionality implied by other values of
+idreg.field.
+
+Other hwcaps may indicate the presence of features which cannot be
+described by ID registers alone. These may be described without
+reference to ID registers, and may refer to other documentation.
+
+
+3. The hwcaps exposed in AT_HWCAP
+---------------------------------
+
+HWCAP_FP
+ Functionality implied by ID_AA64PFR0_EL1.FP == 0b0000.
+
+HWCAP_ASIMD
+ Functionality implied by ID_AA64PFR0_EL1.AdvSIMD == 0b0000.
+
+HWCAP_EVTSTRM
+ The generic timer is configured to generate events at a frequency of
+ approximately 10KHz.
+
+HWCAP_AES
+ Functionality implied by ID_AA64ISAR0_EL1.AES == 0b0001.
+
+HWCAP_PMULL
+ Functionality implied by ID_AA64ISAR0_EL1.AES == 0b0010.
+
+HWCAP_SHA1
+ Functionality implied by ID_AA64ISAR0_EL1.SHA1 == 0b0001.
+
+HWCAP_SHA2
+ Functionality implied by ID_AA64ISAR0_EL1.SHA2 == 0b0001.
+
+HWCAP_CRC32
+ Functionality implied by ID_AA64ISAR0_EL1.CRC32 == 0b0001.
+
+HWCAP_ATOMICS
+ Functionality implied by ID_AA64ISAR0_EL1.Atomic == 0b0010.
+
+HWCAP_FPHP
+ Functionality implied by ID_AA64PFR0_EL1.FP == 0b0001.
+
+HWCAP_ASIMDHP
+ Functionality implied by ID_AA64PFR0_EL1.AdvSIMD == 0b0001.
+
+HWCAP_CPUID
+ EL0 access to certain ID registers is available, to the extent
+ described by Documentation/arm64/cpu-feature-registers.rst.
+
+ These ID registers may imply the availability of features.
+
+HWCAP_ASIMDRDM
+ Functionality implied by ID_AA64ISAR0_EL1.RDM == 0b0001.
+
+HWCAP_JSCVT
+ Functionality implied by ID_AA64ISAR1_EL1.JSCVT == 0b0001.
+
+HWCAP_FCMA
+ Functionality implied by ID_AA64ISAR1_EL1.FCMA == 0b0001.
+
+HWCAP_LRCPC
+ Functionality implied by ID_AA64ISAR1_EL1.LRCPC == 0b0001.
+
+HWCAP_DCPOP
+ Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0001.
+
+HWCAP_SHA3
+ Functionality implied by ID_AA64ISAR0_EL1.SHA3 == 0b0001.
+
+HWCAP_SM3
+ Functionality implied by ID_AA64ISAR0_EL1.SM3 == 0b0001.
+
+HWCAP_SM4
+ Functionality implied by ID_AA64ISAR0_EL1.SM4 == 0b0001.
+
+HWCAP_ASIMDDP
+ Functionality implied by ID_AA64ISAR0_EL1.DP == 0b0001.
+
+HWCAP_SHA512
+ Functionality implied by ID_AA64ISAR0_EL1.SHA2 == 0b0010.
+
+HWCAP_SVE
+ Functionality implied by ID_AA64PFR0_EL1.SVE == 0b0001.
+
+HWCAP_ASIMDFHM
+ Functionality implied by ID_AA64ISAR0_EL1.FHM == 0b0001.
+
+HWCAP_DIT
+ Functionality implied by ID_AA64PFR0_EL1.DIT == 0b0001.
+
+HWCAP_USCAT
+ Functionality implied by ID_AA64MMFR2_EL1.AT == 0b0001.
+
+HWCAP_ILRCPC
+ Functionality implied by ID_AA64ISAR1_EL1.LRCPC == 0b0010.
+
+HWCAP_FLAGM
+ Functionality implied by ID_AA64ISAR0_EL1.TS == 0b0001.
+
+HWCAP_SSBS
+ Functionality implied by ID_AA64PFR1_EL1.SSBS == 0b0010.
+
+HWCAP_SB
+ Functionality implied by ID_AA64ISAR1_EL1.SB == 0b0001.
+
+HWCAP_PACA
+ Functionality implied by ID_AA64ISAR1_EL1.APA == 0b0001 or
+ ID_AA64ISAR1_EL1.API == 0b0001, as described by
+ Documentation/arm64/pointer-authentication.rst.
+
+HWCAP_PACG
+ Functionality implied by ID_AA64ISAR1_EL1.GPA == 0b0001 or
+ ID_AA64ISAR1_EL1.GPI == 0b0001, as described by
+ Documentation/arm64/pointer-authentication.rst.
+
+HWCAP2_DCPODP
+ Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0010.
+
+HWCAP2_SVE2
+ Functionality implied by ID_AA64ZFR0_EL1.SVEVer == 0b0001.
+
+HWCAP2_SVEAES
+ Functionality implied by ID_AA64ZFR0_EL1.AES == 0b0001.
+
+HWCAP2_SVEPMULL
+ Functionality implied by ID_AA64ZFR0_EL1.AES == 0b0010.
+
+HWCAP2_SVEBITPERM
+ Functionality implied by ID_AA64ZFR0_EL1.BitPerm == 0b0001.
+
+HWCAP2_SVESHA3
+ Functionality implied by ID_AA64ZFR0_EL1.SHA3 == 0b0001.
+
+HWCAP2_SVESM4
+ Functionality implied by ID_AA64ZFR0_EL1.SM4 == 0b0001.
+
+HWCAP2_FLAGM2
+ Functionality implied by ID_AA64ISAR0_EL1.TS == 0b0010.
+
+HWCAP2_FRINT
+ Functionality implied by ID_AA64ISAR1_EL1.FRINTTS == 0b0001.
+
+HWCAP2_SVEI8MM
+ Functionality implied by ID_AA64ZFR0_EL1.I8MM == 0b0001.
+
+HWCAP2_SVEF32MM
+ Functionality implied by ID_AA64ZFR0_EL1.F32MM == 0b0001.
+
+HWCAP2_SVEF64MM
+ Functionality implied by ID_AA64ZFR0_EL1.F64MM == 0b0001.
+
+HWCAP2_SVEBF16
+ Functionality implied by ID_AA64ZFR0_EL1.BF16 == 0b0001.
+
+HWCAP2_I8MM
+ Functionality implied by ID_AA64ISAR1_EL1.I8MM == 0b0001.
+
+HWCAP2_BF16
+ Functionality implied by ID_AA64ISAR1_EL1.BF16 == 0b0001.
+
+HWCAP2_DGH
+ Functionality implied by ID_AA64ISAR1_EL1.DGH == 0b0001.
+
+HWCAP2_RNG
+ Functionality implied by ID_AA64ISAR0_EL1.RNDR == 0b0001.
+
+HWCAP2_BTI
+ Functionality implied by ID_AA64PFR0_EL1.BT == 0b0001.
+
+HWCAP2_MTE
+ Functionality implied by ID_AA64PFR1_EL1.MTE == 0b0010, as described
+ by Documentation/arm64/memory-tagging-extension.rst.
+
+HWCAP2_ECV
+ Functionality implied by ID_AA64MMFR0_EL1.ECV == 0b0001.
+
+HWCAP2_AFP
+ Functionality implied by ID_AA64MFR1_EL1.AFP == 0b0001.
+
+HWCAP2_RPRES
+ Functionality implied by ID_AA64ISAR2_EL1.RPRES == 0b0001.
+
+HWCAP2_MTE3
+ Functionality implied by ID_AA64PFR1_EL1.MTE == 0b0011, as described
+ by Documentation/arm64/memory-tagging-extension.rst.
+
+HWCAP2_SME
+ Functionality implied by ID_AA64PFR1_EL1.SME == 0b0001, as described
+ by Documentation/arm64/sme.rst.
+
+HWCAP2_SME_I16I64
+ Functionality implied by ID_AA64SMFR0_EL1.I16I64 == 0b1111.
+
+HWCAP2_SME_F64F64
+ Functionality implied by ID_AA64SMFR0_EL1.F64F64 == 0b1.
+
+HWCAP2_SME_I8I32
+ Functionality implied by ID_AA64SMFR0_EL1.I8I32 == 0b1111.
+
+HWCAP2_SME_F16F32
+ Functionality implied by ID_AA64SMFR0_EL1.F16F32 == 0b1.
+
+HWCAP2_SME_B16F32
+ Functionality implied by ID_AA64SMFR0_EL1.B16F32 == 0b1.
+
+HWCAP2_SME_F32F32
+ Functionality implied by ID_AA64SMFR0_EL1.F32F32 == 0b1.
+
+HWCAP2_SME_FA64
+ Functionality implied by ID_AA64SMFR0_EL1.FA64 == 0b1.
+
+HWCAP2_WFXT
+ Functionality implied by ID_AA64ISAR2_EL1.WFXT == 0b0010.
+
+HWCAP2_EBF16
+ Functionality implied by ID_AA64ISAR1_EL1.BF16 == 0b0010.
+
+HWCAP2_SVE_EBF16
+ Functionality implied by ID_AA64ZFR0_EL1.BF16 == 0b0010.
+
+HWCAP2_CSSC
+ Functionality implied by ID_AA64ISAR2_EL1.CSSC == 0b0001.
+
+HWCAP2_RPRFM
+ Functionality implied by ID_AA64ISAR2_EL1.RPRFM == 0b0001.
+
+HWCAP2_SVE2P1
+ Functionality implied by ID_AA64ZFR0_EL1.SVEver == 0b0010.
+
+HWCAP2_SME2
+ Functionality implied by ID_AA64SMFR0_EL1.SMEver == 0b0001.
+
+HWCAP2_SME2P1
+ Functionality implied by ID_AA64SMFR0_EL1.SMEver == 0b0010.
+
+HWCAP2_SMEI16I32
+ Functionality implied by ID_AA64SMFR0_EL1.I16I32 == 0b0101
+
+HWCAP2_SMEBI32I32
+ Functionality implied by ID_AA64SMFR0_EL1.BI32I32 == 0b1
+
+HWCAP2_SMEB16B16
+ Functionality implied by ID_AA64SMFR0_EL1.B16B16 == 0b1
+
+HWCAP2_SMEF16F16
+ Functionality implied by ID_AA64SMFR0_EL1.F16F16 == 0b1
+
+4. Unused AT_HWCAP bits
+-----------------------
+
+For interoperation with userspace, the kernel guarantees that bits 62
+and 63 of AT_HWCAP will always be returned as 0.