cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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ixgbe.rst (24882B)


      1.. SPDX-License-Identifier: GPL-2.0+
      2
      3===========================================================================
      4Linux Base Driver for the Intel(R) Ethernet 10 Gigabit PCI Express Adapters
      5===========================================================================
      6
      7Intel 10 Gigabit Linux driver.
      8Copyright(c) 1999-2018 Intel Corporation.
      9
     10Contents
     11========
     12
     13- Identifying Your Adapter
     14- Command Line Parameters
     15- Additional Configurations
     16- Known Issues
     17- Support
     18
     19Identifying Your Adapter
     20========================
     21The driver is compatible with devices based on the following:
     22
     23 * Intel(R) Ethernet Controller 82598
     24 * Intel(R) Ethernet Controller 82599
     25 * Intel(R) Ethernet Controller X520
     26 * Intel(R) Ethernet Controller X540
     27 * Intel(R) Ethernet Controller x550
     28 * Intel(R) Ethernet Controller X552
     29 * Intel(R) Ethernet Controller X553
     30
     31For information on how to identify your adapter, and for the latest Intel
     32network drivers, refer to the Intel Support website:
     33https://www.intel.com/support
     34
     35SFP+ Devices with Pluggable Optics
     36----------------------------------
     37
     3882599-BASED ADAPTERS
     39~~~~~~~~~~~~~~~~~~~~
     40NOTES:
     41- If your 82599-based Intel(R) Network Adapter came with Intel optics or is an
     42Intel(R) Ethernet Server Adapter X520-2, then it only supports Intel optics
     43and/or the direct attach cables listed below.
     44- When 82599-based SFP+ devices are connected back to back, they should be set
     45to the same Speed setting via ethtool. Results may vary if you mix speed
     46settings.
     47
     48+---------------+---------------------------------------+------------------+
     49| Supplier      | Type                                  | Part Numbers     |
     50+===============+=======================================+==================+
     51| SR Modules                                                               |
     52+---------------+---------------------------------------+------------------+
     53| Intel         | DUAL RATE 1G/10G SFP+ SR (bailed)     | FTLX8571D3BCV-IT |
     54+---------------+---------------------------------------+------------------+
     55| Intel         | DUAL RATE 1G/10G SFP+ SR (bailed)     | AFBR-703SDZ-IN2  |
     56+---------------+---------------------------------------+------------------+
     57| Intel         | DUAL RATE 1G/10G SFP+ SR (bailed)     | AFBR-703SDDZ-IN1 |
     58+---------------+---------------------------------------+------------------+
     59| LR Modules                                                               |
     60+---------------+---------------------------------------+------------------+
     61| Intel         | DUAL RATE 1G/10G SFP+ LR (bailed)     | FTLX1471D3BCV-IT |
     62+---------------+---------------------------------------+------------------+
     63| Intel         | DUAL RATE 1G/10G SFP+ LR (bailed)     | AFCT-701SDZ-IN2  |
     64+---------------+---------------------------------------+------------------+
     65| Intel         | DUAL RATE 1G/10G SFP+ LR (bailed)     | AFCT-701SDDZ-IN1 |
     66+---------------+---------------------------------------+------------------+
     67
     68The following is a list of 3rd party SFP+ modules that have received some
     69testing. Not all modules are applicable to all devices.
     70
     71+---------------+---------------------------------------+------------------+
     72| Supplier      | Type                                  | Part Numbers     |
     73+===============+=======================================+==================+
     74| Finisar       | SFP+ SR bailed, 10g single rate       | FTLX8571D3BCL    |
     75+---------------+---------------------------------------+------------------+
     76| Avago         | SFP+ SR bailed, 10g single rate       | AFBR-700SDZ      |
     77+---------------+---------------------------------------+------------------+
     78| Finisar       | SFP+ LR bailed, 10g single rate       | FTLX1471D3BCL    |
     79+---------------+---------------------------------------+------------------+
     80| Finisar       | DUAL RATE 1G/10G SFP+ SR (No Bail)    | FTLX8571D3QCV-IT |
     81+---------------+---------------------------------------+------------------+
     82| Avago         | DUAL RATE 1G/10G SFP+ SR (No Bail)    | AFBR-703SDZ-IN1  |
     83+---------------+---------------------------------------+------------------+
     84| Finisar       | DUAL RATE 1G/10G SFP+ LR (No Bail)    | FTLX1471D3QCV-IT |
     85+---------------+---------------------------------------+------------------+
     86| Avago         | DUAL RATE 1G/10G SFP+ LR (No Bail)    | AFCT-701SDZ-IN1  |
     87+---------------+---------------------------------------+------------------+
     88| Finisar       | 1000BASE-T SFP                        | FCLF8522P2BTL    |
     89+---------------+---------------------------------------+------------------+
     90| Avago         | 1000BASE-T                            | ABCU-5710RZ      |
     91+---------------+---------------------------------------+------------------+
     92| HP            | 1000BASE-SX SFP                       | 453153-001       |
     93+---------------+---------------------------------------+------------------+
     94
     9582599-based adapters support all passive and active limiting direct attach
     96cables that comply with SFF-8431 v4.1 and SFF-8472 v10.4 specifications.
     97
     98Laser turns off for SFP+ when ifconfig ethX down
     99~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    100"ifconfig ethX down" turns off the laser for 82599-based SFP+ fiber adapters.
    101"ifconfig ethX up" turns on the laser.
    102Alternatively, you can use "ip link set [down/up] dev ethX" to turn the
    103laser off and on.
    104
    105
    10682599-based QSFP+ Adapters
    107~~~~~~~~~~~~~~~~~~~~~~~~~~
    108NOTES:
    109- If your 82599-based Intel(R) Network Adapter came with Intel optics, it only
    110supports Intel optics.
    111- 82599-based QSFP+ adapters only support 4x10 Gbps connections.  1x40 Gbps
    112connections are not supported. QSFP+ link partners must be configured for
    1134x10 Gbps.
    114- 82599-based QSFP+ adapters do not support automatic link speed detection.
    115The link speed must be configured to either 10 Gbps or 1 Gbps to match the link
    116partners speed capabilities. Incorrect speed configurations will result in
    117failure to link.
    118- Intel(R) Ethernet Converged Network Adapter X520-Q1 only supports the optics
    119and direct attach cables listed below.
    120
    121+---------------+---------------------------------------+------------------+
    122| Supplier      | Type                                  | Part Numbers     |
    123+===============+=======================================+==================+
    124| Intel         | DUAL RATE 1G/10G QSFP+ SRL (bailed)   | E10GQSFPSR       |
    125+---------------+---------------------------------------+------------------+
    126
    12782599-based QSFP+ adapters support all passive and active limiting QSFP+
    128direct attach cables that comply with SFF-8436 v4.1 specifications.
    129
    13082598-BASED ADAPTERS
    131~~~~~~~~~~~~~~~~~~~~
    132NOTES:
    133- Intel(r) Ethernet Network Adapters that support removable optical modules
    134only support their original module type (for example, the Intel(R) 10 Gigabit
    135SR Dual Port Express Module only supports SR optical modules). If you plug in
    136a different type of module, the driver will not load.
    137- Hot Swapping/hot plugging optical modules is not supported.
    138- Only single speed, 10 gigabit modules are supported.
    139- LAN on Motherboard (LOMs) may support DA, SR, or LR modules. Other module
    140types are not supported. Please see your system documentation for details.
    141
    142The following is a list of SFP+ modules and direct attach cables that have
    143received some testing. Not all modules are applicable to all devices.
    144
    145+---------------+---------------------------------------+------------------+
    146| Supplier      | Type                                  | Part Numbers     |
    147+===============+=======================================+==================+
    148| Finisar       | SFP+ SR bailed, 10g single rate       | FTLX8571D3BCL    |
    149+---------------+---------------------------------------+------------------+
    150| Avago         | SFP+ SR bailed, 10g single rate       | AFBR-700SDZ      |
    151+---------------+---------------------------------------+------------------+
    152| Finisar       | SFP+ LR bailed, 10g single rate       | FTLX1471D3BCL    |
    153+---------------+---------------------------------------+------------------+
    154
    15582598-based adapters support all passive direct attach cables that comply with
    156SFF-8431 v4.1 and SFF-8472 v10.4 specifications. Active direct attach cables
    157are not supported.
    158
    159Third party optic modules and cables referred to above are listed only for the
    160purpose of highlighting third party specifications and potential
    161compatibility, and are not recommendations or endorsements or sponsorship of
    162any third party's product by Intel. Intel is not endorsing or promoting
    163products made by any third party and the third party reference is provided
    164only to share information regarding certain optic modules and cables with the
    165above specifications. There may be other manufacturers or suppliers, producing
    166or supplying optic modules and cables with similar or matching descriptions.
    167Customers must use their own discretion and diligence to purchase optic
    168modules and cables from any third party of their choice. Customers are solely
    169responsible for assessing the suitability of the product and/or devices and
    170for the selection of the vendor for purchasing any product. THE OPTIC MODULES
    171AND CABLES REFERRED TO ABOVE ARE NOT WARRANTED OR SUPPORTED BY INTEL. INTEL
    172ASSUMES NO LIABILITY WHATSOEVER, AND INTEL DISCLAIMS ANY EXPRESS OR IMPLIED
    173WARRANTY, RELATING TO SALE AND/OR USE OF SUCH THIRD PARTY PRODUCTS OR
    174SELECTION OF VENDOR BY CUSTOMERS.
    175
    176Command Line Parameters
    177=======================
    178
    179max_vfs
    180-------
    181:Valid Range: 1-63
    182
    183This parameter adds support for SR-IOV. It causes the driver to spawn up to
    184max_vfs worth of virtual functions.
    185If the value is greater than 0 it will also force the VMDq parameter to be 1 or
    186more.
    187
    188NOTE: This parameter is only used on kernel 3.7.x and below. On kernel 3.8.x
    189and above, use sysfs to enable VFs. Also, for Red Hat distributions, this
    190parameter is only used on version 6.6 and older. For version 6.7 and newer, use
    191sysfs. For example::
    192
    193  #echo $num_vf_enabled > /sys/class/net/$dev/device/sriov_numvfs // enable VFs
    194  #echo 0 > /sys/class/net/$dev/device/sriov_numvfs               //disable VFs
    195
    196The parameters for the driver are referenced by position. Thus, if you have a
    197dual port adapter, or more than one adapter in your system, and want N virtual
    198functions per port, you must specify a number for each port with each parameter
    199separated by a comma. For example::
    200
    201  modprobe ixgbe max_vfs=4
    202
    203This will spawn 4 VFs on the first port.
    204
    205::
    206
    207  modprobe ixgbe max_vfs=2,4
    208
    209This will spawn 2 VFs on the first port and 4 VFs on the second port.
    210
    211NOTE: Caution must be used in loading the driver with these parameters.
    212Depending on your system configuration, number of slots, etc., it is impossible
    213to predict in all cases where the positions would be on the command line.
    214
    215NOTE: Neither the device nor the driver control how VFs are mapped into config
    216space. Bus layout will vary by operating system. On operating systems that
    217support it, you can check sysfs to find the mapping.
    218
    219NOTE: When either SR-IOV mode or VMDq mode is enabled, hardware VLAN filtering
    220and VLAN tag stripping/insertion will remain enabled. Please remove the old
    221VLAN filter before the new VLAN filter is added. For example,
    222
    223::
    224
    225  ip link set eth0 vf 0 vlan 100 // set VLAN 100 for VF 0
    226  ip link set eth0 vf 0 vlan 0   // Delete VLAN 100
    227  ip link set eth0 vf 0 vlan 200 // set a new VLAN 200 for VF 0
    228
    229With kernel 3.6, the driver supports the simultaneous usage of max_vfs and DCB
    230features, subject to the constraints described below. Prior to kernel 3.6, the
    231driver did not support the simultaneous operation of max_vfs greater than 0 and
    232the DCB features (multiple traffic classes utilizing Priority Flow Control and
    233Extended Transmission Selection).
    234
    235When DCB is enabled, network traffic is transmitted and received through
    236multiple traffic classes (packet buffers in the NIC). The traffic is associated
    237with a specific class based on priority, which has a value of 0 through 7 used
    238in the VLAN tag. When SR-IOV is not enabled, each traffic class is associated
    239with a set of receive/transmit descriptor queue pairs. The number of queue
    240pairs for a given traffic class depends on the hardware configuration. When
    241SR-IOV is enabled, the descriptor queue pairs are grouped into pools. The
    242Physical Function (PF) and each Virtual Function (VF) is allocated a pool of
    243receive/transmit descriptor queue pairs. When multiple traffic classes are
    244configured (for example, DCB is enabled), each pool contains a queue pair from
    245each traffic class. When a single traffic class is configured in the hardware,
    246the pools contain multiple queue pairs from the single traffic class.
    247
    248The number of VFs that can be allocated depends on the number of traffic
    249classes that can be enabled. The configurable number of traffic classes for
    250each enabled VF is as follows:
    2510 - 15 VFs = Up to 8 traffic classes, depending on device support
    25216 - 31 VFs = Up to 4 traffic classes
    25332 - 63 VFs = 1 traffic class
    254
    255When VFs are configured, the PF is allocated one pool as well. The PF supports
    256the DCB features with the constraint that each traffic class will only use a
    257single queue pair. When zero VFs are configured, the PF can support multiple
    258queue pairs per traffic class.
    259
    260allow_unsupported_sfp
    261---------------------
    262:Valid Range: 0,1
    263:Default Value: 0 (disabled)
    264
    265This parameter allows unsupported and untested SFP+ modules on 82599-based
    266adapters, as long as the type of module is known to the driver.
    267
    268debug
    269-----
    270:Valid Range: 0-16 (0=none,...,16=all)
    271:Default Value: 0
    272
    273This parameter adjusts the level of debug messages displayed in the system
    274logs.
    275
    276
    277Additional Features and Configurations
    278======================================
    279
    280Flow Control
    281------------
    282Ethernet Flow Control (IEEE 802.3x) can be configured with ethtool to enable
    283receiving and transmitting pause frames for ixgbe. When transmit is enabled,
    284pause frames are generated when the receive packet buffer crosses a predefined
    285threshold. When receive is enabled, the transmit unit will halt for the time
    286delay specified when a pause frame is received.
    287
    288NOTE: You must have a flow control capable link partner.
    289
    290Flow Control is enabled by default.
    291
    292Use ethtool to change the flow control settings. To enable or disable Rx or
    293Tx Flow Control::
    294
    295  ethtool -A eth? rx <on|off> tx <on|off>
    296
    297Note: This command only enables or disables Flow Control if auto-negotiation is
    298disabled. If auto-negotiation is enabled, this command changes the parameters
    299used for auto-negotiation with the link partner.
    300
    301To enable or disable auto-negotiation::
    302
    303  ethtool -s eth? autoneg <on|off>
    304
    305Note: Flow Control auto-negotiation is part of link auto-negotiation. Depending
    306on your device, you may not be able to change the auto-negotiation setting.
    307
    308NOTE: For 82598 backplane cards entering 1 gigabit mode, flow control default
    309behavior is changed to off. Flow control in 1 gigabit mode on these devices can
    310lead to transmit hangs.
    311
    312Intel(R) Ethernet Flow Director
    313-------------------------------
    314The Intel Ethernet Flow Director performs the following tasks:
    315
    316- Directs receive packets according to their flows to different queues.
    317- Enables tight control on routing a flow in the platform.
    318- Matches flows and CPU cores for flow affinity.
    319- Supports multiple parameters for flexible flow classification and load
    320  balancing (in SFP mode only).
    321
    322NOTE: Intel Ethernet Flow Director masking works in the opposite manner from
    323subnet masking. In the following command::
    324
    325  #ethtool -N eth11 flow-type ip4 src-ip 172.4.1.2 m 255.0.0.0 dst-ip \
    326  172.21.1.1 m 255.128.0.0 action 31
    327
    328The src-ip value that is written to the filter will be 0.4.1.2, not 172.0.0.0
    329as might be expected. Similarly, the dst-ip value written to the filter will be
    3300.21.1.1, not 172.0.0.0.
    331
    332To enable or disable the Intel Ethernet Flow Director::
    333
    334  # ethtool -K ethX ntuple <on|off>
    335
    336When disabling ntuple filters, all the user programmed filters are flushed from
    337the driver cache and hardware. All needed filters must be re-added when ntuple
    338is re-enabled.
    339
    340To add a filter that directs packet to queue 2, use -U or -N switch::
    341
    342  # ethtool -N ethX flow-type tcp4 src-ip 192.168.10.1 dst-ip \
    343  192.168.10.2 src-port 2000 dst-port 2001 action 2 [loc 1]
    344
    345To see the list of filters currently present::
    346
    347  # ethtool <-u|-n> ethX
    348
    349Sideband Perfect Filters
    350------------------------
    351Sideband Perfect Filters are used to direct traffic that matches specified
    352characteristics. They are enabled through ethtool's ntuple interface. To add a
    353new filter use the following command::
    354
    355  ethtool -U <device> flow-type <type> src-ip <ip> dst-ip <ip> src-port <port> \
    356  dst-port <port> action <queue>
    357
    358Where:
    359  <device> - the ethernet device to program
    360  <type> - can be ip4, tcp4, udp4, or sctp4
    361  <ip> - the IP address to match on
    362  <port> - the port number to match on
    363  <queue> - the queue to direct traffic towards (-1 discards the matched traffic)
    364
    365Use the following command to delete a filter::
    366
    367  ethtool -U <device> delete <N>
    368
    369Where <N> is the filter id displayed when printing all the active filters, and
    370may also have been specified using "loc <N>" when adding the filter.
    371
    372The following example matches TCP traffic sent from 192.168.0.1, port 5300,
    373directed to 192.168.0.5, port 80, and sends it to queue 7::
    374
    375  ethtool -U enp130s0 flow-type tcp4 src-ip 192.168.0.1 dst-ip 192.168.0.5 \
    376  src-port 5300 dst-port 80 action 7
    377
    378For each flow-type, the programmed filters must all have the same matching
    379input set. For example, issuing the following two commands is acceptable::
    380
    381  ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.1 src-port 5300 action 7
    382  ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.5 src-port 55 action 10
    383
    384Issuing the next two commands, however, is not acceptable, since the first
    385specifies src-ip and the second specifies dst-ip::
    386
    387  ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.1 src-port 5300 action 7
    388  ethtool -U enp130s0 flow-type ip4 dst-ip 192.168.0.5 src-port 55 action 10
    389
    390The second command will fail with an error. You may program multiple filters
    391with the same fields, using different values, but, on one device, you may not
    392program two TCP4 filters with different matching fields.
    393
    394Matching on a sub-portion of a field is not supported by the ixgbe driver, thus
    395partial mask fields are not supported.
    396
    397To create filters that direct traffic to a specific Virtual Function, use the
    398"user-def" parameter. Specify the user-def as a 64 bit value, where the lower 32
    399bits represents the queue number, while the next 8 bits represent which VF.
    400Note that 0 is the PF, so the VF identifier is offset by 1. For example::
    401
    402  ... user-def 0x800000002 ...
    403
    404specifies to direct traffic to Virtual Function 7 (8 minus 1) into queue 2 of
    405that VF.
    406
    407Note that these filters will not break internal routing rules, and will not
    408route traffic that otherwise would not have been sent to the specified Virtual
    409Function.
    410
    411Jumbo Frames
    412------------
    413Jumbo Frames support is enabled by changing the Maximum Transmission Unit (MTU)
    414to a value larger than the default value of 1500.
    415
    416Use the ifconfig command to increase the MTU size. For example, enter the
    417following where <x> is the interface number::
    418
    419  ifconfig eth<x> mtu 9000 up
    420
    421Alternatively, you can use the ip command as follows::
    422
    423  ip link set mtu 9000 dev eth<x>
    424  ip link set up dev eth<x>
    425
    426This setting is not saved across reboots. The setting change can be made
    427permanent by adding 'MTU=9000' to the file::
    428
    429  /etc/sysconfig/network-scripts/ifcfg-eth<x> // for RHEL
    430  /etc/sysconfig/network/<config_file> // for SLES
    431
    432NOTE: The maximum MTU setting for Jumbo Frames is 9710. This value coincides
    433with the maximum Jumbo Frames size of 9728 bytes.
    434
    435NOTE: This driver will attempt to use multiple page sized buffers to receive
    436each jumbo packet. This should help to avoid buffer starvation issues when
    437allocating receive packets.
    438
    439NOTE: For 82599-based network connections, if you are enabling jumbo frames in
    440a virtual function (VF), jumbo frames must first be enabled in the physical
    441function (PF). The VF MTU setting cannot be larger than the PF MTU.
    442
    443NBASE-T Support
    444---------------
    445The ixgbe driver supports NBASE-T on some devices. However, the advertisement
    446of NBASE-T speeds is suppressed by default, to accommodate broken network
    447switches which cannot cope with advertised NBASE-T speeds. Use the ethtool
    448command to enable advertising NBASE-T speeds on devices which support it::
    449
    450  ethtool -s eth? advertise 0x1800000001028
    451
    452On Linux systems with INTERFACES(5), this can be specified as a pre-up command
    453in /etc/network/interfaces so that the interface is always brought up with
    454NBASE-T support, e.g.::
    455
    456  iface eth? inet dhcp
    457       pre-up ethtool -s eth? advertise 0x1800000001028 || true
    458
    459Generic Receive Offload, aka GRO
    460--------------------------------
    461The driver supports the in-kernel software implementation of GRO. GRO has
    462shown that by coalescing Rx traffic into larger chunks of data, CPU
    463utilization can be significantly reduced when under large Rx load. GRO is an
    464evolution of the previously-used LRO interface. GRO is able to coalesce
    465other protocols besides TCP. It's also safe to use with configurations that
    466are problematic for LRO, namely bridging and iSCSI.
    467
    468Data Center Bridging (DCB)
    469--------------------------
    470NOTE:
    471The kernel assumes that TC0 is available, and will disable Priority Flow
    472Control (PFC) on the device if TC0 is not available. To fix this, ensure TC0 is
    473enabled when setting up DCB on your switch.
    474
    475DCB is a configuration Quality of Service implementation in hardware. It uses
    476the VLAN priority tag (802.1p) to filter traffic. That means that there are 8
    477different priorities that traffic can be filtered into. It also enables
    478priority flow control (802.1Qbb) which can limit or eliminate the number of
    479dropped packets during network stress. Bandwidth can be allocated to each of
    480these priorities, which is enforced at the hardware level (802.1Qaz).
    481
    482Adapter firmware implements LLDP and DCBX protocol agents as per 802.1AB and
    483802.1Qaz respectively. The firmware based DCBX agent runs in willing mode only
    484and can accept settings from a DCBX capable peer. Software configuration of
    485DCBX parameters via dcbtool/lldptool are not supported.
    486
    487The ixgbe driver implements the DCB netlink interface layer to allow user-space
    488to communicate with the driver and query DCB configuration for the port.
    489
    490ethtool
    491-------
    492The driver utilizes the ethtool interface for driver configuration and
    493diagnostics, as well as displaying statistical information. The latest ethtool
    494version is required for this functionality. Download it at:
    495https://www.kernel.org/pub/software/network/ethtool/
    496
    497FCoE
    498----
    499The ixgbe driver supports Fiber Channel over Ethernet (FCoE) and Data Center
    500Bridging (DCB). This code has no default effect on the regular driver
    501operation. Configuring DCB and FCoE is outside the scope of this README. Refer
    502to http://www.open-fcoe.org/ for FCoE project information and contact
    503ixgbe-eedc@lists.sourceforge.net for DCB information.
    504
    505MAC and VLAN anti-spoofing feature
    506----------------------------------
    507When a malicious driver attempts to send a spoofed packet, it is dropped by the
    508hardware and not transmitted.
    509
    510An interrupt is sent to the PF driver notifying it of the spoof attempt. When a
    511spoofed packet is detected, the PF driver will send the following message to
    512the system log (displayed by the "dmesg" command)::
    513
    514  ixgbe ethX: ixgbe_spoof_check: n spoofed packets detected
    515
    516where "x" is the PF interface number; and "n" is number of spoofed packets.
    517NOTE: This feature can be disabled for a specific Virtual Function (VF)::
    518
    519  ip link set <pf dev> vf <vf id> spoofchk {off|on}
    520
    521IPsec Offload
    522-------------
    523The ixgbe driver supports IPsec Hardware Offload.  When creating Security
    524Associations with "ip xfrm ..." the 'offload' tag option can be used to
    525register the IPsec SA with the driver in order to get higher throughput in
    526the secure communications.
    527
    528The offload is also supported for ixgbe's VFs, but the VF must be set as
    529'trusted' and the support must be enabled with::
    530
    531  ethtool --set-priv-flags eth<x> vf-ipsec on
    532  ip link set eth<x> vf <y> trust on
    533
    534
    535Known Issues/Troubleshooting
    536============================
    537
    538Enabling SR-IOV in a 64-bit Microsoft Windows Server 2012/R2 guest OS
    539---------------------------------------------------------------------
    540Linux KVM Hypervisor/VMM supports direct assignment of a PCIe device to a VM.
    541This includes traditional PCIe devices, as well as SR-IOV-capable devices based
    542on the Intel Ethernet Controller XL710.
    543
    544
    545Support
    546=======
    547For general information, go to the Intel support website at:
    548
    549https://www.intel.com/support/
    550
    551or the Intel Wired Networking project hosted by Sourceforge at:
    552
    553https://sourceforge.net/projects/e1000
    554
    555If an issue is identified with the released source code on a supported kernel
    556with a supported adapter, email the specific information related to the issue
    557to e1000-devel@lists.sf.net.