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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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+===========
+VGA Arbiter
+===========
+
+Graphic devices are accessed through ranges in I/O or memory space. While most
+modern devices allow relocation of such ranges, some "Legacy" VGA devices
+implemented on PCI will typically have the same "hard-decoded" addresses as
+they did on ISA. For more details see "PCI Bus Binding to IEEE Std 1275-1994
+Standard for Boot (Initialization Configuration) Firmware Revision 2.1"
+Section 7, Legacy Devices.
+
+The Resource Access Control (RAC) module inside the X server [0] existed for
+the legacy VGA arbitration task (besides other bus management tasks) when more
+than one legacy device co-exists on the same machine. But the problem happens
+when these devices are trying to be accessed by different userspace clients
+(e.g. two server in parallel). Their address assignments conflict. Moreover,
+ideally, being a userspace application, it is not the role of the X server to
+control bus resources. Therefore an arbitration scheme outside of the X server
+is needed to control the sharing of these resources. This document introduces
+the operation of the VGA arbiter implemented for the Linux kernel.
+
+vgaarb kernel/userspace ABI
+---------------------------
+
+The vgaarb is a module of the Linux Kernel. When it is initially loaded, it
+scans all PCI devices and adds the VGA ones inside the arbitration. The
+arbiter then enables/disables the decoding on different devices of the VGA
+legacy instructions. Devices which do not want/need to use the arbiter may
+explicitly tell it by calling vga_set_legacy_decoding().
+
+The kernel exports a char device interface (/dev/vga_arbiter) to the clients,
+which has the following semantics:
+
+open
+ Opens a user instance of the arbiter. By default, it's attached to the
+ default VGA device of the system.
+
+close
+ Close a user instance. Release locks made by the user
+
+read
+ Return a string indicating the status of the target like:
+
+ "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)"
+
+ An IO state string is of the form {io,mem,io+mem,none}, mc and
+ ic are respectively mem and io lock counts (for debugging/
+ diagnostic only). "decodes" indicate what the card currently
+ decodes, "owns" indicates what is currently enabled on it, and
+ "locks" indicates what is locked by this card. If the card is
+ unplugged, we get "invalid" then for card_ID and an -ENODEV
+ error is returned for any command until a new card is targeted.
+
+
+write
+ Write a command to the arbiter. List of commands:
+
+ target <card_ID>
+ switch target to card <card_ID> (see below)
+ lock <io_state>
+ acquires locks on target ("none" is an invalid io_state)
+ trylock <io_state>
+ non-blocking acquire locks on target (returns EBUSY if
+ unsuccessful)
+ unlock <io_state>
+ release locks on target
+ unlock all
+ release all locks on target held by this user (not implemented
+ yet)
+ decodes <io_state>
+ set the legacy decoding attributes for the card
+
+ poll
+ event if something changes on any card (not just the target)
+
+ card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default"
+ to go back to the system default card (TODO: not implemented yet). Currently,
+ only PCI is supported as a prefix, but the userland API may support other bus
+ types in the future, even if the current kernel implementation doesn't.
+
+Note about locks:
+
+The driver keeps track of which user has which locks on which card. It
+supports stacking, like the kernel one. This complexifies the implementation
+a bit, but makes the arbiter more tolerant to user space problems and able
+to properly cleanup in all cases when a process dies.
+Currently, a max of 16 cards can have locks simultaneously issued from
+user space for a given user (file descriptor instance) of the arbiter.
+
+In the case of devices hot-{un,}plugged, there is a hook - pci_notify() - to
+notify them being added/removed in the system and automatically added/removed
+in the arbiter.
+
+There is also an in-kernel API of the arbiter in case DRM, vgacon, or other
+drivers want to use it.
+
+In-kernel interface
+-------------------
+
+.. kernel-doc:: include/linux/vgaarb.h
+ :internal:
+
+.. kernel-doc:: drivers/pci/vgaarb.c
+ :export:
+
+libpciaccess
+------------
+
+To use the vga arbiter char device it was implemented an API inside the
+libpciaccess library. One field was added to struct pci_device (each device
+on the system)::
+
+ /* the type of resource decoded by the device */
+ int vgaarb_rsrc;
+
+Besides it, in pci_system were added::
+
+ int vgaarb_fd;
+ int vga_count;
+ struct pci_device *vga_target;
+ struct pci_device *vga_default_dev;
+
+The vga_count is used to track how many cards are being arbitrated, so for
+instance, if there is only one card, then it can completely escape arbitration.
+
+These functions below acquire VGA resources for the given card and mark those
+resources as locked. If the resources requested are "normal" (and not legacy)
+resources, the arbiter will first check whether the card is doing legacy
+decoding for that type of resource. If yes, the lock is "converted" into a
+legacy resource lock. The arbiter will first look for all VGA cards that
+might conflict and disable their IOs and/or Memory access, including VGA
+forwarding on P2P bridges if necessary, so that the requested resources can
+be used. Then, the card is marked as locking these resources and the IO and/or
+Memory access is enabled on the card (including VGA forwarding on parent
+P2P bridges if any). In the case of vga_arb_lock(), the function will block
+if some conflicting card is already locking one of the required resources (or
+any resource on a different bus segment, since P2P bridges don't differentiate
+VGA memory and IO afaik). If the card already owns the resources, the function
+succeeds. vga_arb_trylock() will return (-EBUSY) instead of blocking. Nested
+calls are supported (a per-resource counter is maintained).
+
+Set the target device of this client. ::
+
+ int pci_device_vgaarb_set_target (struct pci_device *dev);
+
+For instance, in x86 if two devices on the same bus want to lock different
+resources, both will succeed (lock). If devices are in different buses and
+trying to lock different resources, only the first who tried succeeds. ::
+
+ int pci_device_vgaarb_lock (void);
+ int pci_device_vgaarb_trylock (void);
+
+Unlock resources of device. ::
+
+ int pci_device_vgaarb_unlock (void);
+
+Indicates to the arbiter if the card decodes legacy VGA IOs, legacy VGA
+Memory, both, or none. All cards default to both, the card driver (fbdev for
+example) should tell the arbiter if it has disabled legacy decoding, so the
+card can be left out of the arbitration process (and can be safe to take
+interrupts at any time. ::
+
+ int pci_device_vgaarb_decodes (int new_vgaarb_rsrc);
+
+Connects to the arbiter device, allocates the struct ::
+
+ int pci_device_vgaarb_init (void);
+
+Close the connection ::
+
+ void pci_device_vgaarb_fini (void);
+
+xf86VGAArbiter (X server implementation)
+----------------------------------------
+
+X server basically wraps all the functions that touch VGA registers somehow.
+
+References
+----------
+
+Benjamin Herrenschmidt (IBM?) started this work when he discussed such design
+with the Xorg community in 2005 [1, 2]. In the end of 2007, Paulo Zanoni and
+Tiago Vignatti (both of C3SL/Federal University of ParanĂ¡) proceeded his work
+enhancing the kernel code to adapt as a kernel module and also did the
+implementation of the user space side [3]. Now (2009) Tiago Vignatti and Dave
+Airlie finally put this work in shape and queued to Jesse Barnes' PCI tree.
+
+0) https://cgit.freedesktop.org/xorg/xserver/commit/?id=4b42448a2388d40f257774fbffdccaea87bd0347
+1) https://lists.freedesktop.org/archives/xorg/2005-March/006663.html
+2) https://lists.freedesktop.org/archives/xorg/2005-March/006745.html
+3) https://lists.freedesktop.org/archives/xorg/2007-October/029507.html