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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
+
+==================================
+Fprobe - Function entry/exit probe
+==================================
+
+.. Author: Masami Hiramatsu <mhiramat@kernel.org>
+
+Introduction
+============
+
+Fprobe is a function entry/exit probe mechanism based on ftrace.
+Instead of using ftrace full feature, if you only want to attach callbacks
+on function entry and exit, similar to the kprobes and kretprobes, you can
+use fprobe. Compared with kprobes and kretprobes, fprobe gives faster
+instrumentation for multiple functions with single handler. This document
+describes how to use fprobe.
+
+The usage of fprobe
+===================
+
+The fprobe is a wrapper of ftrace (+ kretprobe-like return callback) to
+attach callbacks to multiple function entry and exit. User needs to set up
+the `struct fprobe` and pass it to `register_fprobe()`.
+
+Typically, `fprobe` data structure is initialized with the `entry_handler`
+and/or `exit_handler` as below.
+
+.. code-block:: c
+
+ struct fprobe fp = {
+ .entry_handler = my_entry_callback,
+ .exit_handler = my_exit_callback,
+ };
+
+To enable the fprobe, call one of register_fprobe(), register_fprobe_ips(), and
+register_fprobe_syms(). These functions register the fprobe with different types
+of parameters.
+
+The register_fprobe() enables a fprobe by function-name filters.
+E.g. this enables @fp on "func*()" function except "func2()".::
+
+ register_fprobe(&fp, "func*", "func2");
+
+The register_fprobe_ips() enables a fprobe by ftrace-location addresses.
+E.g.
+
+.. code-block:: c
+
+ unsigned long ips[] = { 0x.... };
+
+ register_fprobe_ips(&fp, ips, ARRAY_SIZE(ips));
+
+And the register_fprobe_syms() enables a fprobe by symbol names.
+E.g.
+
+.. code-block:: c
+
+ char syms[] = {"func1", "func2", "func3"};
+
+ register_fprobe_syms(&fp, syms, ARRAY_SIZE(syms));
+
+To disable (remove from functions) this fprobe, call::
+
+ unregister_fprobe(&fp);
+
+You can temporally (soft) disable the fprobe by::
+
+ disable_fprobe(&fp);
+
+and resume by::
+
+ enable_fprobe(&fp);
+
+The above is defined by including the header::
+
+ #include <linux/fprobe.h>
+
+Same as ftrace, the registered callbacks will start being called some time
+after the register_fprobe() is called and before it returns. See
+:file:`Documentation/trace/ftrace.rst`.
+
+Also, the unregister_fprobe() will guarantee that the both enter and exit
+handlers are no longer being called by functions after unregister_fprobe()
+returns as same as unregister_ftrace_function().
+
+The fprobe entry/exit handler
+=============================
+
+The prototype of the entry/exit callback function is as follows:
+
+.. code-block:: c
+
+ void callback_func(struct fprobe *fp, unsigned long entry_ip, struct pt_regs *regs);
+
+Note that both entry and exit callbacks have same ptototype. The @entry_ip is
+saved at function entry and passed to exit handler.
+
+@fp
+ This is the address of `fprobe` data structure related to this handler.
+ You can embed the `fprobe` to your data structure and get it by
+ container_of() macro from @fp. The @fp must not be NULL.
+
+@entry_ip
+ This is the ftrace address of the traced function (both entry and exit).
+ Note that this may not be the actual entry address of the function but
+ the address where the ftrace is instrumented.
+
+@regs
+ This is the `pt_regs` data structure at the entry and exit. Note that
+ the instruction pointer of @regs may be different from the @entry_ip
+ in the entry_handler. If you need traced instruction pointer, you need
+ to use @entry_ip. On the other hand, in the exit_handler, the instruction
+ pointer of @regs is set to the currect return address.
+
+Share the callbacks with kprobes
+================================
+
+Since the recursion safeness of the fprobe (and ftrace) is a bit different
+from the kprobes, this may cause an issue if user wants to run the same
+code from the fprobe and the kprobes.
+
+Kprobes has per-cpu 'current_kprobe' variable which protects the kprobe
+handler from recursion in all cases. On the other hand, fprobe uses
+only ftrace_test_recursion_trylock(). This allows interrupt context to
+call another (or same) fprobe while the fprobe user handler is running.
+
+This is not a matter if the common callback code has its own recursion
+detection, or it can handle the recursion in the different contexts
+(normal/interrupt/NMI.)
+But if it relies on the 'current_kprobe' recursion lock, it has to check
+kprobe_running() and use kprobe_busy_*() APIs.
+
+Fprobe has FPROBE_FL_KPROBE_SHARED flag to do this. If your common callback
+code will be shared with kprobes, please set FPROBE_FL_KPROBE_SHARED
+*before* registering the fprobe, like:
+
+.. code-block:: c
+
+ fprobe.flags = FPROBE_FL_KPROBE_SHARED;
+
+ register_fprobe(&fprobe, "func*", NULL);
+
+This will protect your common callback from the nested call.
+
+The missed counter
+==================
+
+The `fprobe` data structure has `fprobe::nmissed` counter field as same as
+kprobes.
+This counter counts up when;
+
+ - fprobe fails to take ftrace_recursion lock. This usually means that a function
+ which is traced by other ftrace users is called from the entry_handler.
+
+ - fprobe fails to setup the function exit because of the shortage of rethook
+ (the shadow stack for hooking the function return.)
+
+The `fprobe::nmissed` field counts up in both cases. Therefore, the former
+skips both of entry and exit callback and the latter skips the exit
+callback, but in both case the counter will increase by 1.
+
+Note that if you set the FTRACE_OPS_FL_RECURSION and/or FTRACE_OPS_FL_RCU to
+`fprobe::ops::flags` (ftrace_ops::flags) when registering the fprobe, this
+counter may not work correctly, because ftrace skips the fprobe function which
+increase the counter.
+
+
+Functions and structures
+========================
+
+.. kernel-doc:: include/linux/fprobe.h
+.. kernel-doc:: kernel/trace/fprobe.c
+