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, 469 insertions, 0 deletions

diff --git a/Documentation/powerpc/cxl.rst b/Documentation/powerpc/cxl.rst
new file mode 100644
index 000000000..d2d770576
--- /dev/null
+++ b/Documentation/powerpc/cxl.rst
@@ -0,0 +1,469 @@
+====================================
+Coherent Accelerator Interface (CXL)
+====================================
+
+Introduction
+============
+
+    The coherent accelerator interface is designed to allow the
+    coherent connection of accelerators (FPGAs and other devices) to a
+    POWER system. These devices need to adhere to the Coherent
+    Accelerator Interface Architecture (CAIA).
+
+    IBM refers to this as the Coherent Accelerator Processor Interface
+    or CAPI. In the kernel it's referred to by the name CXL to avoid
+    confusion with the ISDN CAPI subsystem.
+
+    Coherent in this context means that the accelerator and CPUs can
+    both access system memory directly and with the same effective
+    addresses.
+
+
+Hardware overview
+=================
+
+    ::
+
+         POWER8/9             FPGA
+       +----------+        +---------+
+       |          |        |         |
+       |   CPU    |        |   AFU   |
+       |          |        |         |
+       |          |        |         |
+       |          |        |         |
+       +----------+        +---------+
+       |   PHB    |        |         |
+       |   +------+        |   PSL   |
+       |   | CAPP |<------>|         |
+       +---+------+  PCIE  +---------+
+
+    The POWER8/9 chip has a Coherently Attached Processor Proxy (CAPP)
+    unit which is part of the PCIe Host Bridge (PHB). This is managed
+    by Linux by calls into OPAL. Linux doesn't directly program the
+    CAPP.
+
+    The FPGA (or coherently attached device) consists of two parts.
+    The POWER Service Layer (PSL) and the Accelerator Function Unit
+    (AFU). The AFU is used to implement specific functionality behind
+    the PSL. The PSL, among other things, provides memory address
+    translation services to allow each AFU direct access to userspace
+    memory.
+
+    The AFU is the core part of the accelerator (eg. the compression,
+    crypto etc function). The kernel has no knowledge of the function
+    of the AFU. Only userspace interacts directly with the AFU.
+
+    The PSL provides the translation and interrupt services that the
+    AFU needs. This is what the kernel interacts with. For example, if
+    the AFU needs to read a particular effective address, it sends
+    that address to the PSL, the PSL then translates it, fetches the
+    data from memory and returns it to the AFU. If the PSL has a
+    translation miss, it interrupts the kernel and the kernel services
+    the fault. The context to which this fault is serviced is based on
+    who owns that acceleration function.
+
+    - POWER8 and PSL Version 8 are compliant to the CAIA Version 1.0.
+    - POWER9 and PSL Version 9 are compliant to the CAIA Version 2.0.
+
+    This PSL Version 9 provides new features such as:
+
+    * Interaction with the nest MMU on the P9 chip.
+    * Native DMA support.
+    * Supports sending ASB_Notify messages for host thread wakeup.
+    * Supports Atomic operations.
+    * etc.
+
+    Cards with a PSL9 won't work on a POWER8 system and cards with a
+    PSL8 won't work on a POWER9 system.
+
+AFU Modes
+=========
+
+    There are two programming modes supported by the AFU. Dedicated
+    and AFU directed. AFU may support one or both modes.
+
+    When using dedicated mode only one MMU context is supported. In
+    this mode, only one userspace process can use the accelerator at
+    time.
+
+    When using AFU directed mode, up to 16K simultaneous contexts can
+    be supported. This means up to 16K simultaneous userspace
+    applications may use the accelerator (although specific AFUs may
+    support fewer). In this mode, the AFU sends a 16 bit context ID
+    with each of its requests. This tells the PSL which context is
+    associated with each operation. If the PSL can't translate an
+    operation, the ID can also be accessed by the kernel so it can
+    determine the userspace context associated with an operation.
+
+
+MMIO space
+==========
+
+    A portion of the accelerator MMIO space can be directly mapped
+    from the AFU to userspace. Either the whole space can be mapped or
+    just a per context portion. The hardware is self describing, hence
+    the kernel can determine the offset and size of the per context
+    portion.
+
+
+Interrupts
+==========
+
+    AFUs may generate interrupts that are destined for userspace. These
+    are received by the kernel as hardware interrupts and passed onto
+    userspace by a read syscall documented below.
+
+    Data storage faults and error interrupts are handled by the kernel
+    driver.
+
+
+Work Element Descriptor (WED)
+=============================
+
+    The WED is a 64-bit parameter passed to the AFU when a context is
+    started. Its format is up to the AFU hence the kernel has no
+    knowledge of what it represents. Typically it will be the
+    effective address of a work queue or status block where the AFU
+    and userspace can share control and status information.
+
+
+
+
+User API
+========
+
+1. AFU character devices
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+    For AFUs operating in AFU directed mode, two character device
+    files will be created. /dev/cxl/afu0.0m will correspond to a
+    master context and /dev/cxl/afu0.0s will correspond to a slave
+    context. Master contexts have access to the full MMIO space an
+    AFU provides. Slave contexts have access to only the per process
+    MMIO space an AFU provides.
+
+    For AFUs operating in dedicated process mode, the driver will
+    only create a single character device per AFU called
+    /dev/cxl/afu0.0d. This will have access to the entire MMIO space
+    that the AFU provides (like master contexts in AFU directed).
+
+    The types described below are defined in include/uapi/misc/cxl.h
+
+    The following file operations are supported on both slave and
+    master devices.
+
+    A userspace library libcxl is available here:
+
+	https://github.com/ibm-capi/libcxl
+
+    This provides a C interface to this kernel API.
+
+open
+----
+
+    Opens the device and allocates a file descriptor to be used with
+    the rest of the API.
+
+    A dedicated mode AFU only has one context and only allows the
+    device to be opened once.
+
+    An AFU directed mode AFU can have many contexts, the device can be
+    opened once for each context that is available.
+
+    When all available contexts are allocated the open call will fail
+    and return -ENOSPC.
+
+    Note:
+	  IRQs need to be allocated for each context, which may limit
+          the number of contexts that can be created, and therefore
+          how many times the device can be opened. The POWER8 CAPP
+          supports 2040 IRQs and 3 are used by the kernel, so 2037 are
+          left. If 1 IRQ is needed per context, then only 2037
+          contexts can be allocated. If 4 IRQs are needed per context,
+          then only 2037/4 = 509 contexts can be allocated.
+
+
+ioctl
+-----
+
+    CXL_IOCTL_START_WORK:
+        Starts the AFU context and associates it with the current
+        process. Once this ioctl is successfully executed, all memory
+        mapped into this process is accessible to this AFU context
+        using the same effective addresses. No additional calls are
+        required to map/unmap memory. The AFU memory context will be
+        updated as userspace allocates and frees memory. This ioctl
+        returns once the AFU context is started.
+
+        Takes a pointer to a struct cxl_ioctl_start_work
+
+            ::
+
+                struct cxl_ioctl_start_work {
+                        __u64 flags;
+                        __u64 work_element_descriptor;
+                        __u64 amr;
+                        __s16 num_interrupts;
+                        __s16 reserved1;
+                        __s32 reserved2;
+                        __u64 reserved3;
+                        __u64 reserved4;
+                        __u64 reserved5;
+                        __u64 reserved6;
+                };
+
+            flags:
+                Indicates which optional fields in the structure are
+                valid.
+
+            work_element_descriptor:
+                The Work Element Descriptor (WED) is a 64-bit argument
+                defined by the AFU. Typically this is an effective
+                address pointing to an AFU specific structure
+                describing what work to perform.
+
+            amr:
+                Authority Mask Register (AMR), same as the powerpc
+                AMR. This field is only used by the kernel when the
+                corresponding CXL_START_WORK_AMR value is specified in
+                flags. If not specified the kernel will use a default
+                value of 0.
+
+            num_interrupts:
+                Number of userspace interrupts to request. This field
+                is only used by the kernel when the corresponding
+                CXL_START_WORK_NUM_IRQS value is specified in flags.
+                If not specified the minimum number required by the
+                AFU will be allocated. The min and max number can be
+                obtained from sysfs.
+
+            reserved fields:
+                For ABI padding and future extensions
+
+    CXL_IOCTL_GET_PROCESS_ELEMENT:
+        Get the current context id, also known as the process element.
+        The value is returned from the kernel as a __u32.
+
+
+mmap
+----
+
+    An AFU may have an MMIO space to facilitate communication with the
+    AFU. If it does, the MMIO space can be accessed via mmap. The size
+    and contents of this area are specific to the particular AFU. The
+    size can be discovered via sysfs.
+
+    In AFU directed mode, master contexts are allowed to map all of
+    the MMIO space and slave contexts are allowed to only map the per
+    process MMIO space associated with the context. In dedicated
+    process mode the entire MMIO space can always be mapped.
+
+    This mmap call must be done after the START_WORK ioctl.
+
+    Care should be taken when accessing MMIO space. Only 32 and 64-bit
+    accesses are supported by POWER8. Also, the AFU will be designed
+    with a specific endianness, so all MMIO accesses should consider
+    endianness (recommend endian(3) variants like: le64toh(),
+    be64toh() etc). These endian issues equally apply to shared memory
+    queues the WED may describe.
+
+
+read
+----
+
+    Reads events from the AFU. Blocks if no events are pending
+    (unless O_NONBLOCK is supplied). Returns -EIO in the case of an
+    unrecoverable error or if the card is removed.
+
+    read() will always return an integral number of events.
+
+    The buffer passed to read() must be at least 4K bytes.
+
+    The result of the read will be a buffer of one or more events,
+    each event is of type struct cxl_event, of varying size::
+
+            struct cxl_event {
+                    struct cxl_event_header header;
+                    union {
+                            struct cxl_event_afu_interrupt irq;
+                            struct cxl_event_data_storage fault;
+                            struct cxl_event_afu_error afu_error;
+                    };
+            };
+
+    The struct cxl_event_header is defined as
+
+        ::
+
+            struct cxl_event_header {
+                    __u16 type;
+                    __u16 size;
+                    __u16 process_element;
+                    __u16 reserved1;
+            };
+
+        type:
+            This defines the type of event. The type determines how
+            the rest of the event is structured. These types are
+            described below and defined by enum cxl_event_type.
+
+        size:
+            This is the size of the event in bytes including the
+            struct cxl_event_header. The start of the next event can
+            be found at this offset from the start of the current
+            event.
+
+        process_element:
+            Context ID of the event.
+
+        reserved field:
+            For future extensions and padding.
+
+    If the event type is CXL_EVENT_AFU_INTERRUPT then the event
+    structure is defined as
+
+        ::
+
+            struct cxl_event_afu_interrupt {
+                    __u16 flags;
+                    __u16 irq; /* Raised AFU interrupt number */
+                    __u32 reserved1;
+            };
+
+        flags:
+            These flags indicate which optional fields are present
+            in this struct. Currently all fields are mandatory.
+
+        irq:
+            The IRQ number sent by the AFU.
+
+        reserved field:
+            For future extensions and padding.
+
+    If the event type is CXL_EVENT_DATA_STORAGE then the event
+    structure is defined as
+
+        ::
+
+            struct cxl_event_data_storage {
+                    __u16 flags;
+                    __u16 reserved1;
+                    __u32 reserved2;
+                    __u64 addr;
+                    __u64 dsisr;
+                    __u64 reserved3;
+            };
+
+        flags:
+            These flags indicate which optional fields are present in
+            this struct. Currently all fields are mandatory.
+
+        address:
+            The address that the AFU unsuccessfully attempted to
+            access. Valid accesses will be handled transparently by the
+            kernel but invalid accesses will generate this event.
+
+        dsisr:
+            This field gives information on the type of fault. It is a
+            copy of the DSISR from the PSL hardware when the address
+            fault occurred. The form of the DSISR is as defined in the
+            CAIA.
+
+        reserved fields:
+            For future extensions
+
+    If the event type is CXL_EVENT_AFU_ERROR then the event structure
+    is defined as
+
+        ::
+
+            struct cxl_event_afu_error {
+                    __u16 flags;
+                    __u16 reserved1;
+                    __u32 reserved2;
+                    __u64 error;
+            };
+
+        flags:
+            These flags indicate which optional fields are present in
+            this struct. Currently all fields are Mandatory.
+
+        error:
+            Error status from the AFU. Defined by the AFU.
+
+        reserved fields:
+            For future extensions and padding
+
+
+2. Card character device (powerVM guest only)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+    In a powerVM guest, an extra character device is created for the
+    card. The device is only used to write (flash) a new image on the
+    FPGA accelerator. Once the image is written and verified, the
+    device tree is updated and the card is reset to reload the updated
+    image.
+
+open
+----
+
+    Opens the device and allocates a file descriptor to be used with
+    the rest of the API. The device can only be opened once.
+
+ioctl
+-----
+
+CXL_IOCTL_DOWNLOAD_IMAGE / CXL_IOCTL_VALIDATE_IMAGE:
+    Starts and controls flashing a new FPGA image. Partial
+    reconfiguration is not supported (yet), so the image must contain
+    a copy of the PSL and AFU(s). Since an image can be quite large,
+    the caller may have to iterate, splitting the image in smaller
+    chunks.
+
+    Takes a pointer to a struct cxl_adapter_image::
+
+        struct cxl_adapter_image {
+            __u64 flags;
+            __u64 data;
+            __u64 len_data;
+            __u64 len_image;
+            __u64 reserved1;
+            __u64 reserved2;
+            __u64 reserved3;
+            __u64 reserved4;
+        };
+
+    flags:
+        These flags indicate which optional fields are present in
+        this struct. Currently all fields are mandatory.
+
+    data:
+        Pointer to a buffer with part of the image to write to the
+        card.
+
+    len_data:
+        Size of the buffer pointed to by data.
+
+    len_image:
+        Full size of the image.
+
+
+Sysfs Class
+===========
+
+    A cxl sysfs class is added under /sys/class/cxl to facilitate
+    enumeration and tuning of the accelerators. Its layout is
+    described in Documentation/ABI/testing/sysfs-class-cxl
+
+
+Udev rules
+==========
+
+    The following udev rules could be used to create a symlink to the
+    most logical chardev to use in any programming mode (afuX.Yd for
+    dedicated, afuX.Ys for afu directed), since the API is virtually
+    identical for each::
+
+	SUBSYSTEM=="cxl", ATTRS{mode}=="dedicated_process", SYMLINK="cxl/%b"
+	SUBSYSTEM=="cxl", ATTRS{mode}=="afu_directed", \
+	                  KERNEL=="afu[0-9]*.[0-9]*s", SYMLINK="cxl/%b"