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, 468 insertions, 0 deletions

diff --git a/Documentation/networking/device_drivers/ethernet/intel/ixgb.rst b/Documentation/networking/device_drivers/ethernet/intel/ixgb.rst
new file mode 100644
index 000000000..c6a233e68
--- /dev/null
+++ b/Documentation/networking/device_drivers/ethernet/intel/ixgb.rst
@@ -0,0 +1,468 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+=====================================================================
+Linux Base Driver for 10 Gigabit Intel(R) Ethernet Network Connection
+=====================================================================
+
+October 1, 2018
+
+
+Contents
+========
+
+- In This Release
+- Identifying Your Adapter
+- Command Line Parameters
+- Improving Performance
+- Additional Configurations
+- Known Issues/Troubleshooting
+- Support
+
+
+
+In This Release
+===============
+
+This file describes the ixgb Linux Base Driver for the 10 Gigabit Intel(R)
+Network Connection.  This driver includes support for Itanium(R)2-based
+systems.
+
+For questions related to hardware requirements, refer to the documentation
+supplied with your 10 Gigabit adapter.  All hardware requirements listed apply
+to use with Linux.
+
+The following features are available in this kernel:
+ - Native VLANs
+ - Channel Bonding (teaming)
+ - SNMP
+
+Channel Bonding documentation can be found in the Linux kernel source:
+/Documentation/networking/bonding.rst
+
+The driver information previously displayed in the /proc filesystem is not
+supported in this release.  Alternatively, you can use ethtool (version 1.6
+or later), lspci, and iproute2 to obtain the same information.
+
+Instructions on updating ethtool can be found in the section "Additional
+Configurations" later in this document.
+
+
+Identifying Your Adapter
+========================
+
+The following Intel network adapters are compatible with the drivers in this
+release:
+
++------------+------------------------------+----------------------------------+
+| Controller | Adapter Name                 | Physical Layer                   |
++============+==============================+==================================+
+| 82597EX    | Intel(R) PRO/10GbE LR/SR/CX4 | - 10G Base-LR (fiber)            |
+|            | Server Adapters              | - 10G Base-SR (fiber)            |
+|            |                              | - 10G Base-CX4 (copper)          |
++------------+------------------------------+----------------------------------+
+
+For more information on how to identify your adapter, go to the Adapter &
+Driver ID Guide at:
+
+    https://support.intel.com
+
+
+Command Line Parameters
+=======================
+
+If the driver is built as a module, the  following optional parameters are
+used by entering them on the command line with the modprobe command using
+this syntax::
+
+    modprobe ixgb [<option>=<VAL1>,<VAL2>,...]
+
+For example, with two 10GbE PCI adapters, entering::
+
+    modprobe ixgb TxDescriptors=80,128
+
+loads the ixgb driver with 80 TX resources for the first adapter and 128 TX
+resources for the second adapter.
+
+The default value for each parameter is generally the recommended setting,
+unless otherwise noted.
+
+Copybreak
+---------
+:Valid Range: 0-XXXX
+:Default Value: 256
+
+    This is the maximum size of packet that is copied to a new buffer on
+    receive.
+
+Debug
+-----
+:Valid Range: 0-16 (0=none,...,16=all)
+:Default Value: 0
+
+    This parameter adjusts the level of debug messages displayed in the
+    system logs.
+
+FlowControl
+-----------
+:Valid Range: 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx)
+:Default Value: 1 if no EEPROM, otherwise read from EEPROM
+
+    This parameter controls the automatic generation(Tx) and response(Rx) to
+    Ethernet PAUSE frames.  There are hardware bugs associated with enabling
+    Tx flow control so beware.
+
+RxDescriptors
+-------------
+:Valid Range: 64-4096
+:Default Value: 1024
+
+    This value is the number of receive descriptors allocated by the driver.
+    Increasing this value allows the driver to buffer more incoming packets.
+    Each descriptor is 16 bytes.  A receive buffer is also allocated for
+    each descriptor and can be either 2048, 4056, 8192, or 16384 bytes,
+    depending on the MTU setting.  When the MTU size is 1500 or less, the
+    receive buffer size is 2048 bytes. When the MTU is greater than 1500 the
+    receive buffer size will be either 4056, 8192, or 16384 bytes.  The
+    maximum MTU size is 16114.
+
+TxDescriptors
+-------------
+:Valid Range: 64-4096
+:Default Value: 256
+
+    This value is the number of transmit descriptors allocated by the driver.
+    Increasing this value allows the driver to queue more transmits.  Each
+    descriptor is 16 bytes.
+
+RxIntDelay
+----------
+:Valid Range: 0-65535 (0=off)
+:Default Value: 72
+
+    This value delays the generation of receive interrupts in units of
+    0.8192 microseconds.  Receive interrupt reduction can improve CPU
+    efficiency if properly tuned for specific network traffic.  Increasing
+    this value adds extra latency to frame reception and can end up
+    decreasing the throughput of TCP traffic.  If the system is reporting
+    dropped receives, this value may be set too high, causing the driver to
+    run out of available receive descriptors.
+
+TxIntDelay
+----------
+:Valid Range: 0-65535 (0=off)
+:Default Value: 32
+
+    This value delays the generation of transmit interrupts in units of
+    0.8192 microseconds.  Transmit interrupt reduction can improve CPU
+    efficiency if properly tuned for specific network traffic.  Increasing
+    this value adds extra latency to frame transmission and can end up
+    decreasing the throughput of TCP traffic.  If this value is set too high,
+    it will cause the driver to run out of available transmit descriptors.
+
+XsumRX
+------
+:Valid Range: 0-1
+:Default Value: 1
+
+    A value of '1' indicates that the driver should enable IP checksum
+    offload for received packets (both UDP and TCP) to the adapter hardware.
+
+RxFCHighThresh
+--------------
+:Valid Range: 1,536-262,136 (0x600 - 0x3FFF8, 8 byte granularity)
+:Default Value: 196,608 (0x30000)
+
+    Receive Flow control high threshold (when we send a pause frame)
+
+RxFCLowThresh
+-------------
+:Valid Range: 64-262,136 (0x40 - 0x3FFF8, 8 byte granularity)
+:Default Value: 163,840 (0x28000)
+
+    Receive Flow control low threshold (when we send a resume frame)
+
+FCReqTimeout
+------------
+:Valid Range: 1-65535
+:Default Value: 65535
+
+    Flow control request timeout (how long to pause the link partner's tx)
+
+IntDelayEnable
+--------------
+:Value Range: 0,1
+:Default Value: 1
+
+    Interrupt Delay, 0 disables transmit interrupt delay and 1 enables it.
+
+
+Improving Performance
+=====================
+
+With the 10 Gigabit server adapters, the default Linux configuration will
+very likely limit the total available throughput artificially.  There is a set
+of configuration changes that, when applied together, will increase the ability
+of Linux to transmit and receive data.  The following enhancements were
+originally acquired from settings published at https://www.spec.org/web99/ for
+various submitted results using Linux.
+
+NOTE:
+  These changes are only suggestions, and serve as a starting point for
+  tuning your network performance.
+
+The changes are made in three major ways, listed in order of greatest effect:
+
+- Use ip link to modify the mtu (maximum transmission unit) and the txqueuelen
+  parameter.
+- Use sysctl to modify /proc parameters (essentially kernel tuning)
+- Use setpci to modify the MMRBC field in PCI-X configuration space to increase
+  transmit burst lengths on the bus.
+
+NOTE:
+  setpci modifies the adapter's configuration registers to allow it to read
+  up to 4k bytes at a time (for transmits).  However, for some systems the
+  behavior after modifying this register may be undefined (possibly errors of
+  some kind).  A power-cycle, hard reset or explicitly setting the e6 register
+  back to 22 (setpci -d 8086:1a48 e6.b=22) may be required to get back to a
+  stable configuration.
+
+- COPY these lines and paste them into ixgb_perf.sh:
+
+::
+
+  #!/bin/bash
+  echo "configuring network performance , edit this file to change the interface
+  or device ID of 10GbE card"
+  # set mmrbc to 4k reads, modify only Intel 10GbE device IDs
+  # replace 1a48 with appropriate 10GbE device's ID installed on the system,
+  # if needed.
+  setpci -d 8086:1a48 e6.b=2e
+  # set the MTU (max transmission unit) - it requires your switch and clients
+  # to change as well.
+  # set the txqueuelen
+  # your ixgb adapter should be loaded as eth1 for this to work, change if needed
+  ip li set dev eth1 mtu 9000 txqueuelen 1000 up
+  # call the sysctl utility to modify /proc/sys entries
+  sysctl -p ./sysctl_ixgb.conf
+
+- COPY these lines and paste them into sysctl_ixgb.conf:
+
+::
+
+  # some of the defaults may be different for your kernel
+  # call this file with sysctl -p <this file>
+  # these are just suggested values that worked well to increase throughput in
+  # several network benchmark tests, your mileage may vary
+
+  ### IPV4 specific settings
+  # turn TCP timestamp support off, default 1, reduces CPU use
+  net.ipv4.tcp_timestamps = 0
+  # turn SACK support off, default on
+  # on systems with a VERY fast bus -> memory interface this is the big gainer
+  net.ipv4.tcp_sack = 0
+  # set min/default/max TCP read buffer, default 4096 87380 174760
+  net.ipv4.tcp_rmem = 10000000 10000000 10000000
+  # set min/pressure/max TCP write buffer, default 4096 16384 131072
+  net.ipv4.tcp_wmem = 10000000 10000000 10000000
+  # set min/pressure/max TCP buffer space, default 31744 32256 32768
+  net.ipv4.tcp_mem = 10000000 10000000 10000000
+
+  ### CORE settings (mostly for socket and UDP effect)
+  # set maximum receive socket buffer size, default 131071
+  net.core.rmem_max = 524287
+  # set maximum send socket buffer size, default 131071
+  net.core.wmem_max = 524287
+  # set default receive socket buffer size, default 65535
+  net.core.rmem_default = 524287
+  # set default send socket buffer size, default 65535
+  net.core.wmem_default = 524287
+  # set maximum amount of option memory buffers, default 10240
+  net.core.optmem_max = 524287
+  # set number of unprocessed input packets before kernel starts dropping them; default 300
+  net.core.netdev_max_backlog = 300000
+
+Edit the ixgb_perf.sh script if necessary to change eth1 to whatever interface
+your ixgb driver is using and/or replace '1a48' with appropriate 10GbE device's
+ID installed on the system.
+
+NOTE:
+  Unless these scripts are added to the boot process, these changes will
+  only last only until the next system reboot.
+
+
+Resolving Slow UDP Traffic
+--------------------------
+If your server does not seem to be able to receive UDP traffic as fast as it
+can receive TCP traffic, it could be because Linux, by default, does not set
+the network stack buffers as large as they need to be to support high UDP
+transfer rates.  One way to alleviate this problem is to allow more memory to
+be used by the IP stack to store incoming data.
+
+For instance, use the commands::
+
+    sysctl -w net.core.rmem_max=262143
+
+and::
+
+    sysctl -w net.core.rmem_default=262143
+
+to increase the read buffer memory max and default to 262143 (256k - 1) from
+defaults of max=131071 (128k - 1) and default=65535 (64k - 1).  These variables
+will increase the amount of memory used by the network stack for receives, and
+can be increased significantly more if necessary for your application.
+
+
+Additional Configurations
+=========================
+
+Configuring the Driver on Different Distributions
+-------------------------------------------------
+Configuring a network driver to load properly when the system is started is
+distribution dependent. Typically, the configuration process involves adding
+an alias line to /etc/modprobe.conf as well as editing other system startup
+scripts and/or configuration files.  Many popular Linux distributions ship
+with tools to make these changes for you.  To learn the proper way to
+configure a network device for your system, refer to your distribution
+documentation.  If during this process you are asked for the driver or module
+name, the name for the Linux Base Driver for the Intel 10GbE Family of
+Adapters is ixgb.
+
+Viewing Link Messages
+---------------------
+Link messages will not be displayed to the console if the distribution is
+restricting system messages. In order to see network driver link messages on
+your console, set dmesg to eight by entering the following::
+
+    dmesg -n 8
+
+NOTE: This setting is not saved across reboots.
+
+Jumbo Frames
+------------
+The driver supports Jumbo Frames for all adapters. Jumbo Frames support is
+enabled by changing the MTU to a value larger than the default of 1500.
+The maximum value for the MTU is 16114.  Use the ip command to
+increase the MTU size.  For example::
+
+    ip li set dev ethx mtu 9000
+
+The maximum MTU setting for Jumbo Frames is 16114.  This value coincides
+with the maximum Jumbo Frames size of 16128.
+
+Ethtool
+-------
+The driver utilizes the ethtool interface for driver configuration and
+diagnostics, as well as displaying statistical information.  The ethtool
+version 1.6 or later is required for this functionality.
+
+The latest release of ethtool can be found from
+https://www.kernel.org/pub/software/network/ethtool/
+
+NOTE:
+  The ethtool version 1.6 only supports a limited set of ethtool options.
+  Support for a more complete ethtool feature set can be enabled by
+  upgrading to the latest version.
+
+NAPI
+----
+NAPI (Rx polling mode) is supported in the ixgb driver.
+
+See https://wiki.linuxfoundation.org/networking/napi for more information on
+NAPI.
+
+
+Known Issues/Troubleshooting
+============================
+
+NOTE:
+  After installing the driver, if your Intel Network Connection is not
+  working, verify in the "In This Release" section of the readme that you have
+  installed the correct driver.
+
+Cable Interoperability Issue with Fujitsu XENPAK Module in SmartBits Chassis
+----------------------------------------------------------------------------
+Excessive CRC errors may be observed if the Intel(R) PRO/10GbE CX4
+Server adapter is connected to a Fujitsu XENPAK CX4 module in a SmartBits
+chassis using 15 m/24AWG cable assemblies manufactured by Fujitsu or Leoni.
+The CRC errors may be received either by the Intel(R) PRO/10GbE CX4
+Server adapter or the SmartBits. If this situation occurs using a different
+cable assembly may resolve the issue.
+
+Cable Interoperability Issues with HP Procurve 3400cl Switch Port
+-----------------------------------------------------------------
+Excessive CRC errors may be observed if the Intel(R) PRO/10GbE CX4 Server
+adapter is connected to an HP Procurve 3400cl switch port using short cables
+(1 m or shorter). If this situation occurs, using a longer cable may resolve
+the issue.
+
+Excessive CRC errors may be observed using Fujitsu 24AWG cable assemblies that
+Are 10 m or longer or where using a Leoni 15 m/24AWG cable assembly. The CRC
+errors may be received either by the CX4 Server adapter or at the switch. If
+this situation occurs, using a different cable assembly may resolve the issue.
+
+Jumbo Frames System Requirement
+-------------------------------
+Memory allocation failures have been observed on Linux systems with 64 MB
+of RAM or less that are running Jumbo Frames.  If you are using Jumbo
+Frames, your system may require more than the advertised minimum
+requirement of 64 MB of system memory.
+
+Performance Degradation with Jumbo Frames
+-----------------------------------------
+Degradation in throughput performance may be observed in some Jumbo frames
+environments.  If this is observed, increasing the application's socket buffer
+size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values may help.
+See the specific application manual and /usr/src/linux*/Documentation/
+networking/ip-sysctl.txt for more details.
+
+Allocating Rx Buffers when Using Jumbo Frames
+---------------------------------------------
+Allocating Rx buffers when using Jumbo Frames on 2.6.x kernels may fail if
+the available memory is heavily fragmented. This issue may be seen with PCI-X
+adapters or with packet split disabled. This can be reduced or eliminated
+by changing the amount of available memory for receive buffer allocation, by
+increasing /proc/sys/vm/min_free_kbytes.
+
+Multiple Interfaces on Same Ethernet Broadcast Network
+------------------------------------------------------
+Due to the default ARP behavior on Linux, it is not possible to have
+one system on two IP networks in the same Ethernet broadcast domain
+(non-partitioned switch) behave as expected.  All Ethernet interfaces
+will respond to IP traffic for any IP address assigned to the system.
+This results in unbalanced receive traffic.
+
+If you have multiple interfaces in a server, do either of the following:
+
+  - Turn on ARP filtering by entering::
+
+      echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter
+
+  - Install the interfaces in separate broadcast domains - either in
+    different switches or in a switch partitioned to VLANs.
+
+UDP Stress Test Dropped Packet Issue
+--------------------------------------
+Under small packets UDP stress test with 10GbE driver, the Linux system
+may drop UDP packets due to the fullness of socket buffers. You may want
+to change the driver's Flow Control variables to the minimum value for
+controlling packet reception.
+
+Tx Hangs Possible Under Stress
+------------------------------
+Under stress conditions, if TX hangs occur, turning off TSO
+"ethtool -K eth0 tso off" may resolve the problem.
+
+
+Support
+=======
+For general information, go to the Intel support website at:
+
+https://www.intel.com/support/
+
+or the Intel Wired Networking project hosted by Sourceforge at:
+
+https://sourceforge.net/projects/e1000
+
+If an issue is identified with the released source code on a supported kernel
+with a supported adapter, email the specific information related to the issue
+to e1000-devel@lists.sf.net