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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
+
+========================================
+ACPI considerations for PCI host bridges
+========================================
+
+The general rule is that the ACPI namespace should describe everything the
+OS might use unless there's another way for the OS to find it [1, 2].
+
+For example, there's no standard hardware mechanism for enumerating PCI
+host bridges, so the ACPI namespace must describe each host bridge, the
+method for accessing PCI config space below it, the address space windows
+the host bridge forwards to PCI (using _CRS), and the routing of legacy
+INTx interrupts (using _PRT).
+
+PCI devices, which are below the host bridge, generally do not need to be
+described via ACPI. The OS can discover them via the standard PCI
+enumeration mechanism, using config accesses to discover and identify
+devices and read and size their BARs. However, ACPI may describe PCI
+devices if it provides power management or hotplug functionality for them
+or if the device has INTx interrupts connected by platform interrupt
+controllers and a _PRT is needed to describe those connections.
+
+ACPI resource description is done via _CRS objects of devices in the ACPI
+namespace [2]. The _CRS is like a generalized PCI BAR: the OS can read
+_CRS and figure out what resource is being consumed even if it doesn't have
+a driver for the device [3]. That's important because it means an old OS
+can work correctly even on a system with new devices unknown to the OS.
+The new devices might not do anything, but the OS can at least make sure no
+resources conflict with them.
+
+Static tables like MCFG, HPET, ECDT, etc., are *not* mechanisms for
+reserving address space. The static tables are for things the OS needs to
+know early in boot, before it can parse the ACPI namespace. If a new table
+is defined, an old OS needs to operate correctly even though it ignores the
+table. _CRS allows that because it is generic and understood by the old
+OS; a static table does not.
+
+If the OS is expected to manage a non-discoverable device described via
+ACPI, that device will have a specific _HID/_CID that tells the OS what
+driver to bind to it, and the _CRS tells the OS and the driver where the
+device's registers are.
+
+PCI host bridges are PNP0A03 or PNP0A08 devices. Their _CRS should
+describe all the address space they consume. This includes all the windows
+they forward down to the PCI bus, as well as registers of the host bridge
+itself that are not forwarded to PCI. The host bridge registers include
+things like secondary/subordinate bus registers that determine the bus
+range below the bridge, window registers that describe the apertures, etc.
+These are all device-specific, non-architected things, so the only way a
+PNP0A03/PNP0A08 driver can manage them is via _PRS/_CRS/_SRS, which contain
+the device-specific details. The host bridge registers also include ECAM
+space, since it is consumed by the host bridge.
+
+ACPI defines a Consumer/Producer bit to distinguish the bridge registers
+("Consumer") from the bridge apertures ("Producer") [4, 5], but early
+BIOSes didn't use that bit correctly. The result is that the current ACPI
+spec defines Consumer/Producer only for the Extended Address Space
+descriptors; the bit should be ignored in the older QWord/DWord/Word
+Address Space descriptors. Consequently, OSes have to assume all
+QWord/DWord/Word descriptors are windows.
+
+Prior to the addition of Extended Address Space descriptors, the failure of
+Consumer/Producer meant there was no way to describe bridge registers in
+the PNP0A03/PNP0A08 device itself. The workaround was to describe the
+bridge registers (including ECAM space) in PNP0C02 catch-all devices [6].
+With the exception of ECAM, the bridge register space is device-specific
+anyway, so the generic PNP0A03/PNP0A08 driver (pci_root.c) has no need to
+know about it.
+
+New architectures should be able to use "Consumer" Extended Address Space
+descriptors in the PNP0A03 device for bridge registers, including ECAM,
+although a strict interpretation of [6] might prohibit this. Old x86 and
+ia64 kernels assume all address space descriptors, including "Consumer"
+Extended Address Space ones, are windows, so it would not be safe to
+describe bridge registers this way on those architectures.
+
+PNP0C02 "motherboard" devices are basically a catch-all. There's no
+programming model for them other than "don't use these resources for
+anything else." So a PNP0C02 _CRS should claim any address space that is
+(1) not claimed by _CRS under any other device object in the ACPI namespace
+and (2) should not be assigned by the OS to something else.
+
+The PCIe spec requires the Enhanced Configuration Access Method (ECAM)
+unless there's a standard firmware interface for config access, e.g., the
+ia64 SAL interface [7]. A host bridge consumes ECAM memory address space
+and converts memory accesses into PCI configuration accesses. The spec
+defines the ECAM address space layout and functionality; only the base of
+the address space is device-specific. An ACPI OS learns the base address
+from either the static MCFG table or a _CBA method in the PNP0A03 device.
+
+The MCFG table must describe the ECAM space of non-hot pluggable host
+bridges [8]. Since MCFG is a static table and can't be updated by hotplug,
+a _CBA method in the PNP0A03 device describes the ECAM space of a
+hot-pluggable host bridge [9]. Note that for both MCFG and _CBA, the base
+address always corresponds to bus 0, even if the bus range below the bridge
+(which is reported via _CRS) doesn't start at 0.
+
+
+[1] ACPI 6.2, sec 6.1:
+ For any device that is on a non-enumerable type of bus (for example, an
+ ISA bus), OSPM enumerates the devices' identifier(s) and the ACPI
+ system firmware must supply an _HID object ... for each device to
+ enable OSPM to do that.
+
+[2] ACPI 6.2, sec 3.7:
+ The OS enumerates motherboard devices simply by reading through the
+ ACPI Namespace looking for devices with hardware IDs.
+
+ Each device enumerated by ACPI includes ACPI-defined objects in the
+ ACPI Namespace that report the hardware resources the device could
+ occupy [_PRS], an object that reports the resources that are currently
+ used by the device [_CRS], and objects for configuring those resources
+ [_SRS]. The information is used by the Plug and Play OS (OSPM) to
+ configure the devices.
+
+[3] ACPI 6.2, sec 6.2:
+ OSPM uses device configuration objects to configure hardware resources
+ for devices enumerated via ACPI. Device configuration objects provide
+ information about current and possible resource requirements, the
+ relationship between shared resources, and methods for configuring
+ hardware resources.
+
+ When OSPM enumerates a device, it calls _PRS to determine the resource
+ requirements of the device. It may also call _CRS to find the current
+ resource settings for the device. Using this information, the Plug and
+ Play system determines what resources the device should consume and
+ sets those resources by calling the device’s _SRS control method.
+
+ In ACPI, devices can consume resources (for example, legacy keyboards),
+ provide resources (for example, a proprietary PCI bridge), or do both.
+ Unless otherwise specified, resources for a device are assumed to be
+ taken from the nearest matching resource above the device in the device
+ hierarchy.
+
+[4] ACPI 6.2, sec 6.4.3.5.1, 2, 3, 4:
+ QWord/DWord/Word Address Space Descriptor (.1, .2, .3)
+ General Flags: Bit [0] Ignored
+
+ Extended Address Space Descriptor (.4)
+ General Flags: Bit [0] Consumer/Producer:
+
+ * 1 – This device consumes this resource
+ * 0 – This device produces and consumes this resource
+
+[5] ACPI 6.2, sec 19.6.43:
+ ResourceUsage specifies whether the Memory range is consumed by
+ this device (ResourceConsumer) or passed on to child devices
+ (ResourceProducer). If nothing is specified, then
+ ResourceConsumer is assumed.
+
+[6] PCI Firmware 3.2, sec 4.1.2:
+ If the operating system does not natively comprehend reserving the
+ MMCFG region, the MMCFG region must be reserved by firmware. The
+ address range reported in the MCFG table or by _CBA method (see Section
+ 4.1.3) must be reserved by declaring a motherboard resource. For most
+ systems, the motherboard resource would appear at the root of the ACPI
+ namespace (under \_SB) in a node with a _HID of EISAID (PNP0C02), and
+ the resources in this case should not be claimed in the root PCI bus’s
+ _CRS. The resources can optionally be returned in Int15 E820 or
+ EFIGetMemoryMap as reserved memory but must always be reported through
+ ACPI as a motherboard resource.
+
+[7] PCI Express 4.0, sec 7.2.2:
+ For systems that are PC-compatible, or that do not implement a
+ processor-architecture-specific firmware interface standard that allows
+ access to the Configuration Space, the ECAM is required as defined in
+ this section.
+
+[8] PCI Firmware 3.2, sec 4.1.2:
+ The MCFG table is an ACPI table that is used to communicate the base
+ addresses corresponding to the non-hot removable PCI Segment Groups
+ range within a PCI Segment Group available to the operating system at
+ boot. This is required for the PC-compatible systems.
+
+ The MCFG table is only used to communicate the base addresses
+ corresponding to the PCI Segment Groups available to the system at
+ boot.
+
+[9] PCI Firmware 3.2, sec 4.1.3:
+ The _CBA (Memory mapped Configuration Base Address) control method is
+ an optional ACPI object that returns the 64-bit memory mapped
+ configuration base address for the hot plug capable host bridge. The
+ base address returned by _CBA is processor-relative address. The _CBA
+ control method evaluates to an Integer.
+
+ This control method appears under a host bridge object. When the _CBA
+ method appears under an active host bridge object, the operating system
+ evaluates this structure to identify the memory mapped configuration
+ base address corresponding to the PCI Segment Group for the bus number
+ range specified in _CRS method. An ACPI name space object that contains
+ the _CBA method must also contain a corresponding _SEG method.