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2018-01-09net: ovs: remove unused hardirq.hYang Shi1-1/+0
Preempt counter APIs have been split out, currently, hardirq.h just includes irq_enter/exit APIs which are not used by openvswitch at all. So, remove the unused hardirq.h. Signed-off-by: Yang Shi <yang.s@alibaba-inc.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: dev@openvswitch.org Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-03openvswitch: do not propagate headroom updates to internal portPaolo Abeni1-8/+1
After commit 3a927bc7cf9d ("ovs: propagate per dp max headroom to all vports") the need_headroom for the internal vport is updated accordingly to the max needed headroom in its datapath. That avoids the pskb_expand_head() costs when sending/forwarding packets towards tunnel devices, at least for some scenarios. We still require such copy when using the ovs-preferred configuration for vxlan tunnels: br_int / \ tap vxlan (remote_ip:X) br_phy \ NIC where the route towards the IP 'X' is via 'br_phy'. When forwarding traffic from the tap towards the vxlan device, we will call pskb_expand_head() in vxlan_build_skb() because br-phy->needed_headroom is equal to tun->needed_headroom. With this change we avoid updating the internal vport needed_headroom, so that in the above scenario no head copy is needed, giving 5% performance improvement in UDP throughput test. As a trade-off, packets sent from the internal port towards a tunnel device will now experience the head copy overhead. The rationale is that the latter use-case is less relevant performance-wise. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-07net: Fix inconsistent teardown and release of private netdev state.David S. Miller1-2/+2
Network devices can allocate reasources and private memory using netdev_ops->ndo_init(). However, the release of these resources can occur in one of two different places. Either netdev_ops->ndo_uninit() or netdev->destructor(). The decision of which operation frees the resources depends upon whether it is necessary for all netdev refs to be released before it is safe to perform the freeing. netdev_ops->ndo_uninit() presumably can occur right after the NETDEV_UNREGISTER notifier completes and the unicast and multicast address lists are flushed. netdev->destructor(), on the other hand, does not run until the netdev references all go away. Further complicating the situation is that netdev->destructor() almost universally does also a free_netdev(). This creates a problem for the logic in register_netdevice(). Because all callers of register_netdevice() manage the freeing of the netdev, and invoke free_netdev(dev) if register_netdevice() fails. If netdev_ops->ndo_init() succeeds, but something else fails inside of register_netdevice(), it does call ndo_ops->ndo_uninit(). But it is not able to invoke netdev->destructor(). This is because netdev->destructor() will do a free_netdev() and then the caller of register_netdevice() will do the same. However, this means that the resources that would normally be released by netdev->destructor() will not be. Over the years drivers have added local hacks to deal with this, by invoking their destructor parts by hand when register_netdevice() fails. Many drivers do not try to deal with this, and instead we have leaks. Let's close this hole by formalizing the distinction between what private things need to be freed up by netdev->destructor() and whether the driver needs unregister_netdevice() to perform the free_netdev(). netdev->priv_destructor() performs all actions to free up the private resources that used to be freed by netdev->destructor(), except for free_netdev(). netdev->needs_free_netdev is a boolean that indicates whether free_netdev() should be done at the end of unregister_netdevice(). Now, register_netdevice() can sanely release all resources after ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit() and netdev->priv_destructor(). And at the end of unregister_netdevice(), we invoke netdev->priv_destructor() and optionally call free_netdev(). Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-15openvswitch: Set internal device max mtu to ETH_MAX_MTU.Jarno Rajahalme1-0/+2
Commit 91572088e3fd ("net: use core MTU range checking in core net infra") changed the openvswitch internal device to use the core net infra for controlling the MTU range, but failed to actually set the max_mtu as described in the commit message, which now defaults to ETH_DATA_LEN. This patch fixes this by setting max_mtu to ETH_MAX_MTU after ether_setup() call. Fixes: 91572088e3fd ("net: use core MTU range checking in core net infra") Signed-off-by: Jarno Rajahalme <jarno@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-09net: make ndo_get_stats64 a void functionstephen hemminger1-3/+1
The network device operation for reading statistics is only called in one place, and it ignores the return value. Having a structure return value is potentially confusing because some future driver could incorrectly assume that the return value was used. Fix all drivers with ndo_get_stats64 to have a void function. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20net: use core MTU range checking in core net infraJarod Wilson1-10/+0
geneve: - Merge __geneve_change_mtu back into geneve_change_mtu, set max_mtu - This one isn't quite as straight-forward as others, could use some closer inspection and testing macvlan: - set min/max_mtu tun: - set min/max_mtu, remove tun_net_change_mtu vxlan: - Merge __vxlan_change_mtu back into vxlan_change_mtu - Set max_mtu to IP_MAX_MTU and retain dynamic MTU range checks in change_mtu function - This one is also not as straight-forward and could use closer inspection and testing from vxlan folks bridge: - set max_mtu of IP_MAX_MTU and retain dynamic MTU range checks in change_mtu function openvswitch: - set min/max_mtu, remove internal_dev_change_mtu - note: max_mtu wasn't checked previously, it's been set to 65535, which is the largest possible size supported sch_teql: - set min/max_mtu (note: max_mtu previously unchecked, used max of 65535) macsec: - min_mtu = 0, max_mtu = 65535 macvlan: - min_mtu = 0, max_mtu = 65535 ntb_netdev: - min_mtu = 0, max_mtu = 65535 veth: - min_mtu = 68, max_mtu = 65535 8021q: - min_mtu = 0, max_mtu = 65535 CC: netdev@vger.kernel.org CC: Nicolas Dichtel <nicolas.dichtel@6wind.com> CC: Hannes Frederic Sowa <hannes@stressinduktion.org> CC: Tom Herbert <tom@herbertland.com> CC: Daniel Borkmann <daniel@iogearbox.net> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Paolo Abeni <pabeni@redhat.com> CC: Jiri Benc <jbenc@redhat.com> CC: WANG Cong <xiyou.wangcong@gmail.com> CC: Roopa Prabhu <roopa@cumulusnetworks.com> CC: Pravin B Shelar <pshelar@ovn.org> CC: Sabrina Dubroca <sd@queasysnail.net> CC: Patrick McHardy <kaber@trash.net> CC: Stephen Hemminger <stephen@networkplumber.org> CC: Pravin Shelar <pshelar@nicira.com> CC: Maxim Krasnyansky <maxk@qti.qualcomm.com> Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-13openvswitch: add NETIF_F_HW_VLAN_STAG_TX to internal devJiri Benc1-1/+1
The internal device does support 802.1AD offloading since 018c1dda5ff1 ("openvswitch: 802.1AD Flow handling, actions, vlan parsing, netlink attributes"). Signed-off-by: Jiri Benc <jbenc@redhat.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Acked-by: Eric Garver <e@erig.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-06OVS: Ignore negative headroom valueIan Wienand1-1/+1
net_device->ndo_set_rx_headroom (introduced in 871b642adebe300be2e50aa5f65a418510f636ec) says "Setting a negtaive value reset the rx headroom to the default value". It seems that the OVS implementation in 3a927bc7cf9d0fbe8f4a8189dd5f8440228f64e7 overlooked this and sets dev->needed_headroom unconditionally. This doesn't have an immediate effect, but can mess up later LL_RESERVED_SPACE calculations, such as done in net/ipv6/mcast.c:mld_newpack. For reference, this issue was found from a skb_panic raised there after the length calculations had given the wrong result. Note the other current users of this interface (drivers/net/tun.c:tun_set_headroom and drivers/net/veth.c:veth_set_rx_headroom) are both checking this correctly thus need no modification. Thanks to Ben for some pointers from the crash dumps! Cc: Benjamin Poirier <bpoirier@suse.com> Cc: Paolo Abeni <pabeni@redhat.com> Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1361414 Signed-off-by: Ian Wienand <iwienand@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03ovs: set name assign type of internal portZhang Shengju1-1/+1
Set name_assign_type of internal port to NET_NAME_USER. Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-17openvswitch: Convert to using IFF_NO_QUEUEPhil Sutter1-2/+1
Cc: Pravin Shelar <pshelar@nicira.com> Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-19ovs: internal_set_rx_headroom() can be staticWu Fengguang1-1/+1
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01ovs: propagate per dp max headroom to all vportsPaolo Abeni1-1/+9
This patch implements bookkeeping support to compute the maximum headroom for all the devices in each datapath. When said value changes, the underlying devs are notified via the ndo_set_rx_headroom method. This also increases the internal vports xmit performance. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-3/+43
Conflicts: net/ipv6/xfrm6_output.c net/openvswitch/flow_netlink.c net/openvswitch/vport-gre.c net/openvswitch/vport-vxlan.c net/openvswitch/vport.c net/openvswitch/vport.h The openvswitch conflicts were overlapping changes. One was the egress tunnel info fix in 'net' and the other was the vport ->send() op simplification in 'net-next'. The xfrm6_output.c conflicts was also a simplification overlapping a bug fix. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22openvswitch: Use dev_queue_xmit for vport send.Pravin B Shelar1-4/+4
With use of lwtunnel, we can directly call dev_queue_xmit() rather than calling netdev vport send operation. Following change make tunnel vport code bit cleaner. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Acked-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22openvswitch: Allocate memory for ovs internal device stats.James Morse1-3/+43
"openvswitch: Remove vport stats" removed the per-vport statistics, in order to use the netdev's statistics fields. "openvswitch: Fix ovs_vport_get_stats()" fixed the export of these stats to user-space, by using the provided netdev_ops to collate them - but ovs internal devices still use an unallocated dev->tstats field to count packets, which are no longer exported by this api. Allocate the dev->tstats field for ovs internal devices, and wire up ndo_get_stats64 with the original implementation of ovs_vport_get_stats(). On its own, "openvswitch: Fix ovs_vport_get_stats()" fixes the OOPs, unmasking a full-on panic on arm64: =============%<============== [<ffffffbffc00ce4c>] internal_dev_recv+0xa8/0x170 [openvswitch] [<ffffffbffc0008b4>] do_output.isra.31+0x60/0x19c [openvswitch] [<ffffffbffc000bf8>] do_execute_actions+0x208/0x11c0 [openvswitch] [<ffffffbffc001c78>] ovs_execute_actions+0xc8/0x238 [openvswitch] [<ffffffbffc003dfc>] ovs_packet_cmd_execute+0x21c/0x288 [openvswitch] [<ffffffc0005e8c5c>] genl_family_rcv_msg+0x1b0/0x310 [<ffffffc0005e8e60>] genl_rcv_msg+0xa4/0xe4 [<ffffffc0005e7ddc>] netlink_rcv_skb+0xb0/0xdc [<ffffffc0005e8a94>] genl_rcv+0x38/0x50 [<ffffffc0005e76c0>] netlink_unicast+0x164/0x210 [<ffffffc0005e7b70>] netlink_sendmsg+0x304/0x368 [<ffffffc0005a21c0>] sock_sendmsg+0x30/0x4c [SNIP] Kernel panic - not syncing: Fatal exception in interrupt =============%<============== Fixes: 8c876639c985 ("openvswitch: Remove vport stats.") Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-30openvswitch: Remove vport stats.Pravin B Shelar1-32/+25
Since all vport types are now backed by netdev, we can directly use netdev stats. Following patch removes redundant stat from vport. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28net: add netif_is_ovs_master helper with IFF_OPENVSWITCH private flagJiri Pirko1-1/+1
Add this helper so code can easily figure out if netdev is openswitch. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21openvswitch: Abstract vport name through ovs_vport_name()Thomas Graf1-1/+0
This allows to get rid of the get_name() vport ops later on. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21openvswitch: Move dev pointer into vport itselfThomas Graf1-22/+15
This is the first step in representing all OVS vports as regular struct net_devices. Move the net_device pointer into the vport structure itself to get rid of struct vport_netdev. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-06openvswitch: Drop packets when interdev is not upChunhe Li1-0/+5
If the internal device is not up, it should drop received packets. Sometimes it receive the broadcast or multicast packets, and the ip protocol stack will casue more cpu usage wasted. Signed-off-by: Chunhe Li <lichunhe@huawei.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-10-28ovs: Turn vports with dependencies into separate modulesThomas Graf1-2/+15
The internal and netdev vport remain part of openvswitch.ko. Encap vports including vxlan, gre, and geneve can be built as separate modules and are loaded on demand. Modules can be unloaded after use. Datapath ports keep a reference to the vport module during their lifetime. Allows to remove the error prone maintenance of the global list vport_ops_list. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-24openvswitch: Enable tunnel GSO for OVS bridge.Pravin B Shelar1-1/+4
Following patch enables all available tunnel GSO features for OVS bridge device so that ovs can use hardware offloads available to underling device. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Andy Zhou <azhou@nicira.com>
2014-07-16net: set name_assign_type in alloc_netdev()Tom Gundersen1-1/+2
Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert all users to pass NET_NAME_UNKNOWN. Coccinelle patch: @@ expression sizeof_priv, name, setup, txqs, rxqs, count; @@ ( -alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs) +alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs) | -alloc_netdev_mq(sizeof_priv, name, setup, count) +alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count) | -alloc_netdev(sizeof_priv, name, setup) +alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup) ) v9: move comments here from the wrong commit Signed-off-by: Tom Gundersen <teg@jklm.no> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-02openvswitch: introduce rtnl ops stubJiri Pirko1-0/+16
This stub now allows userspace to see IFLA_INFO_KIND for ovs master and IFLA_INFO_SLAVE_KIND for slave. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14net: get rid of SET_ETHTOOL_OPSWilfried Klaebe1-1/+1
net: get rid of SET_ETHTOOL_OPS Dave Miller mentioned he'd like to see SET_ETHTOOL_OPS gone. This does that. Mostly done via coccinelle script: @@ struct ethtool_ops *ops; struct net_device *dev; @@ - SET_ETHTOOL_OPS(dev, ops); + dev->ethtool_ops = ops; Compile tested only, but I'd seriously wonder if this broke anything. Suggested-by: Dave Miller <davem@davemloft.net> Signed-off-by: Wilfried Klaebe <w-lkml@lebenslange-mailadresse.de> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-02openvswitch: Enable all GSO features on internal port.Pravin B Shelar1-1/+1
OVS already can handle all types of segmentation offloads that are supported by the kernel. Following patch specifically enables UDP and IPV6 segmentation offloads. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-06-20openvswitch: Add tunneling interface.Pravin B Shelar1-1/+1
Add ovs tunnel interface for set tunnel action for userspace. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-15openvswitch: make skb->csum consistent with rest of networking stack.Pravin B Shelar1-0/+1
Following patch keeps skb->csum correct across ovs. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-04-30openvswitch: Remove unneeded ovs_netdev_get_ifindex()Thomas Graf1-1/+0
The only user is get_dpifindex(), no need to redirect via the port operations. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19net: vlan: rename NETIF_F_HW_VLAN_* feature flags to NETIF_F_HW_VLAN_CTAG_*Patrick McHardy1-1/+1
Rename the hardware VLAN acceleration features to include "CTAG" to indicate that they only support CTAGs. Follow up patches will introduce 802.1ad server provider tagging (STAGs) and require the distinction for hardware not supporting acclerating both. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-16openvswitch: Simplify datapath locking.Pravin B Shelar1-0/+6
Currently OVS uses combination of genl and rtnl lock to protect datapath state. This was done due to networking stack locking. But this has complicated locking and there are few lock ordering issues with new tunneling protocols. Following patch simplifies locking by introducing new ovs mutex and now this lock is used to protect entire ovs state. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-03-17Merge branch 'master' of ↵David S. Miller1-11/+2
git://git.kernel.org/pub/scm/linux/kernel/git/jesse/openvswitch Conflicts: net/openvswitch/vport-internal_dev.c Jesse Gross says: ==================== A couple of minor enhancements for net-next/3.10. The largest is an extension to allow variable length metadata to be passed to userspace with packets. There is a merge conflict in net/openvswitch/vport-internal_dev.c: A existing commit modifies internal_dev_mac_addr() and a new commit deletes it. The new one is correct, so you can just remove that function. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-07ethtool: fix drvinfo strings set in driversJiri Pirko1-1/+1
Use strlcpy where possible to ensure the string is \0 terminated. Use always sizeof(string) instead of 32, ETHTOOL_BUSINFO_LEN and custom defines. Use snprintf instead of sprint. Remove unnecessary inits of ->fw_version Remove unnecessary inits of drvinfo struct. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-04net: remove unnecessary NET_ADDR_RANDOM "bitclean"Jiri Pirko1-1/+0
NET_ADDR_SET is set in dev_set_mac_address() no need to alter dev->addr_assign_type value in drivers. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-04openvswitch: Use eth_mac_addr() instead of duplicating itThomas Graf1-12/+2
bonus: if we ever are to use IFF_LIVE_ADDR_CHANGE for anything further than to check availability in eth_mac_addr(), Open vSwitch will be ready for that. Signed-off-by: Thomas Graf <tgraf@redhat.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2012-08-23openvswitch: Add support for network namespaces.Pravin B Shelar1-1/+6
Following patch adds support for network namespace to openvswitch. Since it must release devices when namespaces are destroyed, a side effect of this patch is that the module no longer keeps a refcount but instead cleans up any state when it is unloaded. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2012-05-25openvswitch: Reset upper layer protocol info on internal devices.Jesse Gross1-0/+8
It's possible that packets that are sent on internal devices (from the OVS perspective) have already traversed the local IP stack. After they go through the internal device, they will again travel through the IP stack which may get confused by the presence of existing information in the skb. The problem can be observed when switching between namespaces. This clears out that information to avoid problems but deliberately leaves other metadata alone. This is to provide maximum flexibility in chaining together OVS and other Linux components. Signed-off-by: Jesse Gross <jesse@nicira.com>
2012-05-04openvswitch: Replace Nicira Networks.Raju Subramanian1-1/+1
Replaced all instances of Nicira Networks(, Inc) to Nicira, Inc. Signed-off-by: Raju Subramanian <rsubramanian@nicira.com> Signed-off-by: Ben Pfaff <blp@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2012-02-16net: use eth_hw_addr_random() and reset addr_assign_typeDanny Kukawka1-1/+2
Use eth_hw_addr_random() instead of calling random_ether_addr() to set addr_assign_type correctly to NET_ADDR_RANDOM. Reset the state to NET_ADDR_PERM as soon as the MAC get changed via .ndo_set_mac_address. v2: adapt to renamed eth_hw_addr_random() Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-17net: remove version.h includes in net/openvswitch/Devendra Naga1-1/+0
remove version.h includes in net/openswitch/ as reported by make versioncheck. Signed-off-by: Devendra Naga <devendra.aaru@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-03net: Add Open vSwitch kernel components.Jesse Gross1-0/+241
Open vSwitch is a multilayer Ethernet switch targeted at virtualized environments. In addition to supporting a variety of features expected in a traditional hardware switch, it enables fine-grained programmatic extension and flow-based control of the network. This control is useful in a wide variety of applications but is particularly important in multi-server virtualization deployments, which are often characterized by highly dynamic endpoints and the need to maintain logical abstractions for multiple tenants. The Open vSwitch datapath provides an in-kernel fast path for packet forwarding. It is complemented by a userspace daemon, ovs-vswitchd, which is able to accept configuration from a variety of sources and translate it into packet processing rules. See http://openvswitch.org for more information and userspace utilities. Signed-off-by: Jesse Gross <jesse@nicira.com>