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().
  ...

1 files changed, 339 insertions, 0 deletions

diff --git a/Documentation/core-api/this_cpu_ops.rst b/Documentation/core-api/this_cpu_ops.rst
new file mode 100644
index 000000000..5cb8b883a
--- /dev/null
+++ b/Documentation/core-api/this_cpu_ops.rst
@@ -0,0 +1,339 @@
+===================
+this_cpu operations
+===================
+
+:Author: Christoph Lameter, August 4th, 2014
+:Author: Pranith Kumar, Aug 2nd, 2014
+
+this_cpu operations are a way of optimizing access to per cpu
+variables associated with the *currently* executing processor. This is
+done through the use of segment registers (or a dedicated register where
+the cpu permanently stored the beginning of the per cpu	area for a
+specific processor).
+
+this_cpu operations add a per cpu variable offset to the processor
+specific per cpu base and encode that operation in the instruction
+operating on the per cpu variable.
+
+This means that there are no atomicity issues between the calculation of
+the offset and the operation on the data. Therefore it is not
+necessary to disable preemption or interrupts to ensure that the
+processor is not changed between the calculation of the address and
+the operation on the data.
+
+Read-modify-write operations are of particular interest. Frequently
+processors have special lower latency instructions that can operate
+without the typical synchronization overhead, but still provide some
+sort of relaxed atomicity guarantees. The x86, for example, can execute
+RMW (Read Modify Write) instructions like inc/dec/cmpxchg without the
+lock prefix and the associated latency penalty.
+
+Access to the variable without the lock prefix is not synchronized but
+synchronization is not necessary since we are dealing with per cpu
+data specific to the currently executing processor. Only the current
+processor should be accessing that variable and therefore there are no
+concurrency issues with other processors in the system.
+
+Please note that accesses by remote processors to a per cpu area are
+exceptional situations and may impact performance and/or correctness
+(remote write operations) of local RMW operations via this_cpu_*.
+
+The main use of the this_cpu operations has been to optimize counter
+operations.
+
+The following this_cpu() operations with implied preemption protection
+are defined. These operations can be used without worrying about
+preemption and interrupts::
+
+	this_cpu_read(pcp)
+	this_cpu_write(pcp, val)
+	this_cpu_add(pcp, val)
+	this_cpu_and(pcp, val)
+	this_cpu_or(pcp, val)
+	this_cpu_add_return(pcp, val)
+	this_cpu_xchg(pcp, nval)
+	this_cpu_cmpxchg(pcp, oval, nval)
+	this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
+	this_cpu_sub(pcp, val)
+	this_cpu_inc(pcp)
+	this_cpu_dec(pcp)
+	this_cpu_sub_return(pcp, val)
+	this_cpu_inc_return(pcp)
+	this_cpu_dec_return(pcp)
+
+
+Inner working of this_cpu operations
+------------------------------------
+
+On x86 the fs: or the gs: segment registers contain the base of the
+per cpu area. It is then possible to simply use the segment override
+to relocate a per cpu relative address to the proper per cpu area for
+the processor. So the relocation to the per cpu base is encoded in the
+instruction via a segment register prefix.
+
+For example::
+
+	DEFINE_PER_CPU(int, x);
+	int z;
+
+	z = this_cpu_read(x);
+
+results in a single instruction::
+
+	mov ax, gs:[x]
+
+instead of a sequence of calculation of the address and then a fetch
+from that address which occurs with the per cpu operations. Before
+this_cpu_ops such sequence also required preempt disable/enable to
+prevent the kernel from moving the thread to a different processor
+while the calculation is performed.
+
+Consider the following this_cpu operation::
+
+	this_cpu_inc(x)
+
+The above results in the following single instruction (no lock prefix!)::
+
+	inc gs:[x]
+
+instead of the following operations required if there is no segment
+register::
+
+	int *y;
+	int cpu;
+
+	cpu = get_cpu();
+	y = per_cpu_ptr(&x, cpu);
+	(*y)++;
+	put_cpu();
+
+Note that these operations can only be used on per cpu data that is
+reserved for a specific processor. Without disabling preemption in the
+surrounding code this_cpu_inc() will only guarantee that one of the
+per cpu counters is correctly incremented. However, there is no
+guarantee that the OS will not move the process directly before or
+after the this_cpu instruction is executed. In general this means that
+the value of the individual counters for each processor are
+meaningless. The sum of all the per cpu counters is the only value
+that is of interest.
+
+Per cpu variables are used for performance reasons. Bouncing cache
+lines can be avoided if multiple processors concurrently go through
+the same code paths.  Since each processor has its own per cpu
+variables no concurrent cache line updates take place. The price that
+has to be paid for this optimization is the need to add up the per cpu
+counters when the value of a counter is needed.
+
+
+Special operations
+------------------
+
+::
+
+	y = this_cpu_ptr(&x)
+
+Takes the offset of a per cpu variable (&x !) and returns the address
+of the per cpu variable that belongs to the currently executing
+processor.  this_cpu_ptr avoids multiple steps that the common
+get_cpu/put_cpu sequence requires. No processor number is
+available. Instead, the offset of the local per cpu area is simply
+added to the per cpu offset.
+
+Note that this operation is usually used in a code segment when
+preemption has been disabled. The pointer is then used to
+access local per cpu data in a critical section. When preemption
+is re-enabled this pointer is usually no longer useful since it may
+no longer point to per cpu data of the current processor.
+
+
+Per cpu variables and offsets
+-----------------------------
+
+Per cpu variables have *offsets* to the beginning of the per cpu
+area. They do not have addresses although they look like that in the
+code. Offsets cannot be directly dereferenced. The offset must be
+added to a base pointer of a per cpu area of a processor in order to
+form a valid address.
+
+Therefore the use of x or &x outside of the context of per cpu
+operations is invalid and will generally be treated like a NULL
+pointer dereference.
+
+::
+
+	DEFINE_PER_CPU(int, x);
+
+In the context of per cpu operations the above implies that x is a per
+cpu variable. Most this_cpu operations take a cpu variable.
+
+::
+
+	int __percpu *p = &x;
+
+&x and hence p is the *offset* of a per cpu variable. this_cpu_ptr()
+takes the offset of a per cpu variable which makes this look a bit
+strange.
+
+
+Operations on a field of a per cpu structure
+--------------------------------------------
+
+Let's say we have a percpu structure::
+
+	struct s {
+		int n,m;
+	};
+
+	DEFINE_PER_CPU(struct s, p);
+
+
+Operations on these fields are straightforward::
+
+	this_cpu_inc(p.m)
+
+	z = this_cpu_cmpxchg(p.m, 0, 1);
+
+
+If we have an offset to struct s::
+
+	struct s __percpu *ps = &p;
+
+	this_cpu_dec(ps->m);
+
+	z = this_cpu_inc_return(ps->n);
+
+
+The calculation of the pointer may require the use of this_cpu_ptr()
+if we do not make use of this_cpu ops later to manipulate fields::
+
+	struct s *pp;
+
+	pp = this_cpu_ptr(&p);
+
+	pp->m--;
+
+	z = pp->n++;
+
+
+Variants of this_cpu ops
+------------------------
+
+this_cpu ops are interrupt safe. Some architectures do not support
+these per cpu local operations. In that case the operation must be
+replaced by code that disables interrupts, then does the operations
+that are guaranteed to be atomic and then re-enable interrupts. Doing
+so is expensive. If there are other reasons why the scheduler cannot
+change the processor we are executing on then there is no reason to
+disable interrupts. For that purpose the following __this_cpu operations
+are provided.
+
+These operations have no guarantee against concurrent interrupts or
+preemption. If a per cpu variable is not used in an interrupt context
+and the scheduler cannot preempt, then they are safe. If any interrupts
+still occur while an operation is in progress and if the interrupt too
+modifies the variable, then RMW actions can not be guaranteed to be
+safe::
+
+	__this_cpu_read(pcp)
+	__this_cpu_write(pcp, val)
+	__this_cpu_add(pcp, val)
+	__this_cpu_and(pcp, val)
+	__this_cpu_or(pcp, val)
+	__this_cpu_add_return(pcp, val)
+	__this_cpu_xchg(pcp, nval)
+	__this_cpu_cmpxchg(pcp, oval, nval)
+	__this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
+	__this_cpu_sub(pcp, val)
+	__this_cpu_inc(pcp)
+	__this_cpu_dec(pcp)
+	__this_cpu_sub_return(pcp, val)
+	__this_cpu_inc_return(pcp)
+	__this_cpu_dec_return(pcp)
+
+
+Will increment x and will not fall-back to code that disables
+interrupts on platforms that cannot accomplish atomicity through
+address relocation and a Read-Modify-Write operation in the same
+instruction.
+
+
+&this_cpu_ptr(pp)->n vs this_cpu_ptr(&pp->n)
+--------------------------------------------
+
+The first operation takes the offset and forms an address and then
+adds the offset of the n field. This may result in two add
+instructions emitted by the compiler.
+
+The second one first adds the two offsets and then does the
+relocation.  IMHO the second form looks cleaner and has an easier time
+with (). The second form also is consistent with the way
+this_cpu_read() and friends are used.
+
+
+Remote access to per cpu data
+------------------------------
+
+Per cpu data structures are designed to be used by one cpu exclusively.
+If you use the variables as intended, this_cpu_ops() are guaranteed to
+be "atomic" as no other CPU has access to these data structures.
+
+There are special cases where you might need to access per cpu data
+structures remotely. It is usually safe to do a remote read access
+and that is frequently done to summarize counters. Remote write access
+something which could be problematic because this_cpu ops do not
+have lock semantics. A remote write may interfere with a this_cpu
+RMW operation.
+
+Remote write accesses to percpu data structures are highly discouraged
+unless absolutely necessary. Please consider using an IPI to wake up
+the remote CPU and perform the update to its per cpu area.
+
+To access per-cpu data structure remotely, typically the per_cpu_ptr()
+function is used::
+
+
+	DEFINE_PER_CPU(struct data, datap);
+
+	struct data *p = per_cpu_ptr(&datap, cpu);
+
+This makes it explicit that we are getting ready to access a percpu
+area remotely.
+
+You can also do the following to convert the datap offset to an address::
+
+	struct data *p = this_cpu_ptr(&datap);
+
+but, passing of pointers calculated via this_cpu_ptr to other cpus is
+unusual and should be avoided.
+
+Remote access are typically only for reading the status of another cpus
+per cpu data. Write accesses can cause unique problems due to the
+relaxed synchronization requirements for this_cpu operations.
+
+One example that illustrates some concerns with write operations is
+the following scenario that occurs because two per cpu variables
+share a cache-line but the relaxed synchronization is applied to
+only one process updating the cache-line.
+
+Consider the following example::
+
+
+	struct test {
+		atomic_t a;
+		int b;
+	};
+
+	DEFINE_PER_CPU(struct test, onecacheline);
+
+There is some concern about what would happen if the field 'a' is updated
+remotely from one processor and the local processor would use this_cpu ops
+to update field b. Care should be taken that such simultaneous accesses to
+data within the same cache line are avoided. Also costly synchronization
+may be necessary. IPIs are generally recommended in such scenarios instead
+of a remote write to the per cpu area of another processor.
+
+Even in cases where the remote writes are rare, please bear in
+mind that a remote write will evict the cache line from the processor
+that most likely will access it. If the processor wakes up and finds a
+missing local cache line of a per cpu area, its performance and hence
+the wake up times will be affected.