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2019-12-09xfrm: add espintcp (RFC 8229)Sabrina Dubroca1-0/+11
TCP encapsulation of IKE and IPsec messages (RFC 8229) is implemented as a TCP ULP, overriding in particular the sendmsg and recvmsg operations. A Stream Parser is used to extract messages out of the TCP stream using the first 2 bytes as length marker. Received IKE messages are put on "ike_queue", waiting to be dequeued by the custom recvmsg implementation. Received ESP messages are sent to XFRM, like with UDP encapsulation. Some of this code is taken from the original submission by Herbert Xu. Currently, only IPv4 is supported, like for UDP encapsulation. Co-developed-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2019-11-21net: Fix Kconfig indentation, continuedKrzysztof Kozlowski1-109/+109
Adjust indentation from spaces to tab (+optional two spaces) as in coding style. This fixes various indentation mixups (seven spaces, tab+one space, etc). Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-26net: Fix Kconfig indentationKrzysztof Kozlowski1-2/+2
Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-08xfrm: make xfrm modes builtinFlorian Westphal1-28/+1
after previous changes, xfrm_mode contains no function pointers anymore and all modules defining such struct contain no code except an init/exit functions to register the xfrm_mode struct with the xfrm core. Just place the xfrm modes core and remove the modules, the run-time xfrm_mode register/unregister functionality is removed. Before: text data bss dec filename 7523 200 2364 10087 net/xfrm/xfrm_input.o 40003 628 440 41071 net/xfrm/xfrm_state.o 15730338 6937080 4046908 26714326 vmlinux 7389 200 2364 9953 net/xfrm/xfrm_input.o 40574 656 440 41670 net/xfrm/xfrm_state.o 15730084 6937068 4046908 26714060 vmlinux The xfrm*_mode_{transport,tunnel,beet} modules are gone. v2: replace CONFIG_INET6_XFRM_MODE_* IS_ENABLED guards with CONFIG_IPV6 ones rather than removing them. Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-07-24net: remove blank lines at end of fileStephen Hemminger1-2/+2
Several files have extra line at end of file. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-01ipmr,ipmr6: Define a uniform vif_deviceYuval Mintz1-0/+5
The two implementations have almost identical structures - vif_device and mif_device. As a step toward uniforming the mr_tables, eliminate the mif_device and relocate the vif_device definition into a new common header file. Also, introduce a common initializing function for setting most of the vif_device fields in a new common source file. This requires modifying the ipv{4,6] Kconfig and ipv4 makefile as we're introducing a new common config option - CONFIG_IP_MROUTE_COMMON. Signed-off-by: Yuval Mintz <yuvalm@mellanox.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-12ip: update policy routing config helpStephen Hemminger1-5/+3
The kernel config help for policy routing was still pointing at an ancient document from 2000 that refers to Linux 2.1. Update it to point to something that is at least occasionally updated. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-16Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-nextDavid S. Miller1-0/+13
Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2017-02-16 1) Make struct xfrm_input_afinfo const, nothing writes to it. From Florian Westphal. 2) Remove all places that write to the afinfo policy backend and make the struct const then. From Florian Westphal. 3) Prepare for packet consuming gro callbacks and add ESP GRO handlers. ESP packets can be decapsulated at the GRO layer then. It saves a round through the stack for each ESP packet. Please note that this has a merge coflict between commit 63fca65d0863 ("net: add confirm_neigh method to dst_ops") from net-next and 3d7d25a68ea5 ("xfrm: policy: remove garbage_collect callback") a2817d8b279b ("xfrm: policy: remove family field") from ipsec-next. The conflict can be solved as it is done in linux-next. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-15esp: Add a software GRO codepathSteffen Klassert1-0/+13
This patch adds GRO ifrastructure and callbacks for ESP on ipv4 and ipv6. In case the GRO layer detects an ESP packet, the esp{4,6}_gro_receive() function does a xfrm state lookup and calls the xfrm input layer if it finds a matching state. The packet will be decapsulated and reinjected it into layer 2. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-02-08gro_cells: move to net/core/gro_cells.cEric Dumazet1-0/+1
We have many gro cells users, so lets move the code to avoid duplication. This creates a CONFIG_GRO_CELLS option. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
Couple conflicts resolved here: 1) In the MACB driver, a bug fix to properly initialize the RX tail pointer properly overlapped with some changes to support variable sized rings. 2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix overlapping with a reorganization of the driver to support ACPI, OF, as well as PCI variants of the chip. 3) In 'net' we had several probe error path bug fixes to the stmmac driver, meanwhile a lot of this code was cleaned up and reorganized in 'net-next'. 4) The cls_flower classifier obtained a helper function in 'net-next' called __fl_delete() and this overlapped with Daniel Borkamann's bug fix to use RCU for object destruction in 'net'. It also overlapped with Jiri's change to guard the rhashtable_remove_fast() call with a check against tc_skip_sw(). 5) In mlx4, a revert bug fix in 'net' overlapped with some unrelated changes in 'net-next'. 6) In geneve, a stale header pointer after pskb_expand_head() bug fix in 'net' overlapped with a large reorganization of the same code in 'net-next'. Since the 'net-next' code no longer had the bug in question, there was nothing to do other than to simply take the 'net-next' hunks. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-28tcp: Set DEFAULT_TCP_CONG to bbr if DEFAULT_BBR is setJulian Wollrath1-0/+1
Signed-off-by: Julian Wollrath <jwollrath@web.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-23net: ip, diag -- Add diag interface for raw socketsCyrill Gorcunov1-0/+8
In criu we are actively using diag interface to collect sockets present in the system when dumping applications. And while for unix, tcp, udp[lite], packet, netlink it works as expected, the raw sockets do not have. Thus add it. v2: - add missing sock_put calls in raw_diag_dump_one (by eric.dumazet@) - implement @destroy for diag requests (by dsa@) v3: - add export of raw_abort for IPv6 (by dsa@) - pass net-admin flag into inet_sk_diag_fill due to changes in net-next branch (by dsa@) v4: - use @pad in struct inet_diag_req_v2 for raw socket protocol specification: raw module carries sockets which may have custom protocol passed from socket() syscall and sole @sdiag_protocol is not enough to match underlied ones - start reporting protocol specifed in socket() call when sockets are raw ones for the same reason: user space tools like ss may parse this attribute and use it for socket matching v5 (by eric.dumazet@): - use sock_hold in raw_sock_get instead of atomic_inc, we're holding (raw_v4_hashinfo|raw_v6_hashinfo)->lock when looking up so counter won't be zero here. v6: - use sdiag_raw_protocol() helper which will access @pad structure used for raw sockets protocol specification: we can't simply rename this member without breaking uapi v7: - sine sdiag_raw_protocol() helper is not suitable for uapi lets rather make an alias structure with proper names. __check_inet_diag_req_raw helper will catch if any of structure unintentionally changed. CC: David S. Miller <davem@davemloft.net> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: David Ahern <dsa@cumulusnetworks.com> CC: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> CC: James Morris <jmorris@namei.org> CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> CC: Patrick McHardy <kaber@trash.net> CC: Andrey Vagin <avagin@openvz.org> CC: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-21tcp_bbr: add BBR congestion controlNeal Cardwell1-0/+18
This commit implements a new TCP congestion control algorithm: BBR (Bottleneck Bandwidth and RTT). A detailed description of BBR will be published in ACM Queue, Vol. 14 No. 5, September-October 2016, as "BBR: Congestion-Based Congestion Control". BBR has significantly increased throughput and reduced latency for connections on Google's internal backbone networks and google.com and YouTube Web servers. BBR requires only changes on the sender side, not in the network or the receiver side. Thus it can be incrementally deployed on today's Internet, or in datacenters. The Internet has predominantly used loss-based congestion control (largely Reno or CUBIC) since the 1980s, relying on packet loss as the signal to slow down. While this worked well for many years, loss-based congestion control is unfortunately out-dated in today's networks. On today's Internet, loss-based congestion control causes the infamous bufferbloat problem, often causing seconds of needless queuing delay, since it fills the bloated buffers in many last-mile links. On today's high-speed long-haul links using commodity switches with shallow buffers, loss-based congestion control has abysmal throughput because it over-reacts to losses caused by transient traffic bursts. In 1981 Kleinrock and Gale showed that the optimal operating point for a network maximizes delivered bandwidth while minimizing delay and loss, not only for single connections but for the network as a whole. Finding that optimal operating point has been elusive, since any single network measurement is ambiguous: network measurements are the result of both bandwidth and propagation delay, and those two cannot be measured simultaneously. While it is impossible to disambiguate any single bandwidth or RTT measurement, a connection's behavior over time tells a clearer story. BBR uses a measurement strategy designed to resolve this ambiguity. It combines these measurements with a robust servo loop using recent control systems advances to implement a distributed congestion control algorithm that reacts to actual congestion, not packet loss or transient queue delay, and is designed to converge with high probability to a point near the optimal operating point. In a nutshell, BBR creates an explicit model of the network pipe by sequentially probing the bottleneck bandwidth and RTT. On the arrival of each ACK, BBR derives the current delivery rate of the last round trip, and feeds it through a windowed max-filter to estimate the bottleneck bandwidth. Conversely it uses a windowed min-filter to estimate the round trip propagation delay. The max-filtered bandwidth and min-filtered RTT estimates form BBR's model of the network pipe. Using its model, BBR sets control parameters to govern sending behavior. The primary control is the pacing rate: BBR applies a gain multiplier to transmit faster or slower than the observed bottleneck bandwidth. The conventional congestion window (cwnd) is now the secondary control; the cwnd is set to a small multiple of the estimated BDP (bandwidth-delay product) in order to allow full utilization and bandwidth probing while bounding the potential amount of queue at the bottleneck. When a BBR connection starts, it enters STARTUP mode and applies a high gain to perform an exponential search to quickly probe the bottleneck bandwidth (doubling its sending rate each round trip, like slow start). However, instead of continuing until it fills up the buffer (i.e. a loss), or until delay or ACK spacing reaches some threshold (like Hystart), it uses its model of the pipe to estimate when that pipe is full: it estimates the pipe is full when it notices the estimated bandwidth has stopped growing. At that point it exits STARTUP and enters DRAIN mode, where it reduces its pacing rate to drain the queue it estimates it has created. Then BBR enters steady state. In steady state, PROBE_BW mode cycles between first pacing faster to probe for more bandwidth, then pacing slower to drain any queue that created if no more bandwidth was available, and then cruising at the estimated bandwidth to utilize the pipe without creating excess queue. Occasionally, on an as-needed basis, it sends significantly slower to probe for RTT (PROBE_RTT mode). BBR has been fully deployed on Google's wide-area backbone networks and we're experimenting with BBR on Google.com and YouTube on a global scale. Replacing CUBIC with BBR has resulted in significant improvements in network latency and application (RPC, browser, and video) metrics. For more details please refer to our upcoming ACM Queue publication. Example performance results, to illustrate the difference between BBR and CUBIC: Resilience to random loss (e.g. from shallow buffers): Consider a netperf TCP_STREAM test lasting 30 secs on an emulated path with a 10Gbps bottleneck, 100ms RTT, and 1% packet loss rate. CUBIC gets 3.27 Mbps, and BBR gets 9150 Mbps (2798x higher). Low latency with the bloated buffers common in today's last-mile links: Consider a netperf TCP_STREAM test lasting 120 secs on an emulated path with a 10Mbps bottleneck, 40ms RTT, and 1000-packet bottleneck buffer. Both fully utilize the bottleneck bandwidth, but BBR achieves this with a median RTT 25x lower (43 ms instead of 1.09 secs). Our long-term goal is to improve the congestion control algorithms used on the Internet. We are hopeful that BBR can help advance the efforts toward this goal, and motivate the community to do further research. Test results, performance evaluations, feedback, and BBR-related discussions are very welcome in the public e-mail list for BBR: https://groups.google.com/forum/#!forum/bbr-dev NOTE: BBR *must* be used with the fq qdisc ("man tc-fq") with pacing enabled, since pacing is integral to the BBR design and implementation. BBR without pacing would not function properly, and may incur unnecessary high packet loss rates. Signed-off-by: Van Jacobson <vanj@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10tcp: add NV congestion controlLawrence Brakmo1-0/+16
TCP-NV (New Vegas) is a major update to TCP-Vegas. An earlier version of NV was presented at 2010's LPC. It is a delayed based congestion avoidance for the data center. This version has been tested within a 10G rack where the HW RTTs are 20-50us and with 1 to 400 flows. A description of TCP-NV, including implementation details as well as experimental results, can be found at: http://www.brakmo.org/networking/tcp-nv/TCPNV.html Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-17ipv4: Remove inet_lro libraryBen Hutchings1-8/+0
There are no longer any in-tree drivers that use it. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16ip_tunnel: replace dst_cache with generic implementationPaolo Abeni1-0/+1
The current ip_tunnel cache implementation is prone to a race that will cause the wrong dst to be cached on cuncurrent dst cache miss and ip tunnel update via netlink. Replacing with the generic implementation fix the issue. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Suggested-and-acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-25ipv4+ipv6: Make INET*_ESP select CRYPTO_ECHAINIVThomas Egerer1-0/+1
The ESP algorithms using CBC mode require echainiv. Hence INET*_ESP have to select CRYPTO_ECHAINIV in order to work properly. This solves the issues caused by a misconfiguration as described in [1]. The original approach, patching crypto/Kconfig was turned down by Herbert Xu [2]. [1] https://lists.strongswan.org/pipermail/users/2015-December/009074.html [2] http://marc.info/?l=linux-crypto-vger&m=145224655809562&w=2 Signed-off-by: Thomas Egerer <hakke_007@gmx.de> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15net: diag: Support destroying TCP sockets.Lorenzo Colitti1-0/+13
This implements SOCK_DESTROY for TCP sockets. It causes all blocking calls on the socket to fail fast with ECONNABORTED and causes a protocol close of the socket. It informs the other end of the connection by sending a RST, i.e., initiating a TCP ABORT as per RFC 793. ECONNABORTED was chosen for consistency with FreeBSD. Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27geneve: Consolidate Geneve functionality in single module.Pravin B Shelar1-14/+0
geneve_core module handles send and receive functionality. This way OVS could use the Geneve API. Now with use of tunnel meatadata mode OVS can directly use Geneve netdevice. So there is no need for separate module for Geneve. Following patch consolidates Geneve protocol processing in single module. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Reviewed-by: Jesse Gross <jesse@nicira.com> Acked-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11tcp: add CDG congestion controlKenneth Klette Jonassen1-0/+20
CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies the TCP sender in order to [1]: o Use the delay gradient as a congestion signal. o Back off with an average probability that is independent of the RTT. o Coexist with flows that use loss-based congestion control, i.e., flows that are unresponsive to the delay signal. o Tolerate packet loss unrelated to congestion. (Disabled by default.) Its FreeBSD implementation was presented for the ICCRG in July 2012; slides are available at http://www.ietf.org/proceedings/84/iccrg.html Running the experiment scenarios in [1] suggests that our implementation achieves more goodput compared with FreeBSD 10.0 senders, although it also causes more queueing delay for a given backoff factor. The loss tolerance heuristic is disabled by default due to safety concerns for its use in the Internet [2, p. 45-46]. We use a variant of the Hybrid Slow start algorithm in tcp_cubic to reduce the probability of slow start overshoot. [1] D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using delay gradients." In Networking 2011, pages 328-341. Springer, 2011. [2] K.K. Jonassen. "Implementing CAIA Delay-Gradient in Linux." MSc thesis. Department of Informatics, University of Oslo, 2015. Cc: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Neal Cardwell <ncardwell@google.com> Cc: David Hayes <davihay@ifi.uio.no> Cc: Andreas Petlund <apetlund@simula.no> Cc: Dave Taht <dave.taht@bufferbloat.net> Cc: Nicolas Kuhn <nicolas.kuhn@telecom-bretagne.eu> Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13geneve: Rename support library as geneve_coreJohn W. Linville1-2/+2
net/ipv4/geneve.c -> net/ipv4/geneve_core.c This name better reflects the purpose of the module. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05net: Move fou_build_header into fou.c and refactorTom Herbert1-0/+9
Move fou_build_header out of ip_tunnel.c and into fou.c splitting it up into fou_build_header, gue_build_header, and fou_build_udp. This allows for other users for TX of FOU or GUE. Change ip_tunnel_encap to call fou_build_header or gue_build_header based on the tunnel encapsulation type. Similarly, added fou_encap_hlen and gue_encap_hlen functions which are called by ip_encap_hlen. New net/fou.h has prototypes and defines for this. Added NET_FOU_IP_TUNNELS configuration. When this is set, IP tunnels can use FOU/GUE and fou module is also selected. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07openvswitch: fix a compilation error when CONFIG_INET is not setW!Andy Zhou1-14/+15
Fix a openvswitch compilation error when CONFIG_INET is not set: ===================================================== In file included from include/net/geneve.h:4:0, from net/openvswitch/flow_netlink.c:45: include/net/udp_tunnel.h: In function 'udp_tunnel_handle_offloads': >> include/net/udp_tunnel.h:100:2: error: implicit declaration of function 'iptunnel_handle_offloads' [-Werror=implicit-function-declaration] >> return iptunnel_handle_offloads(skb, udp_csum, type); >> ^ >> >> include/net/udp_tunnel.h:100:2: warning: return makes pointer from integer without a cast >> >> cc1: some warnings being treated as errors ===================================================== Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06net: Add Geneve tunneling protocol driverAndy Zhou1-0/+14
This adds a device level support for Geneve -- Generic Network Virtualization Encapsulation. The protocol is documented at http://tools.ietf.org/html/draft-gross-geneve-01 Only protocol layer Geneve support is provided by this driver. Openvswitch can be used for configuring, set up and tear down functional Geneve tunnels. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-29net: tcp: add DCTCP congestion control algorithmDaniel Borkmann1-1/+25
This work adds the DataCenter TCP (DCTCP) congestion control algorithm [1], which has been first published at SIGCOMM 2010 [2], resp. follow-up analysis at SIGMETRICS 2011 [3] (and also, more recently as an informational IETF draft available at [4]). DCTCP is an enhancement to the TCP congestion control algorithm for data center networks. Typical data center workloads are i.e. i) partition/aggregate (queries; bursty, delay sensitive), ii) short messages e.g. 50KB-1MB (for coordination and control state; delay sensitive), and iii) large flows e.g. 1MB-100MB (data update; throughput sensitive). DCTCP has therefore been designed for such environments to provide/achieve the following three requirements: * High burst tolerance (incast due to partition/aggregate) * Low latency (short flows, queries) * High throughput (continuous data updates, large file transfers) with commodity, shallow buffered switches The basic idea of its design consists of two fundamentals: i) on the switch side, packets are being marked when its internal queue length > threshold K (K is chosen so that a large enough headroom for marked traffic is still available in the switch queue); ii) the sender/host side maintains a moving average of the fraction of marked packets, so each RTT, F is being updated as follows: F := X / Y, where X is # of marked ACKs, Y is total # of ACKs alpha := (1 - g) * alpha + g * F, where g is a smoothing constant The resulting alpha (iow: probability that switch queue is congested) is then being used in order to adaptively decrease the congestion window W: W := (1 - (alpha / 2)) * W The means for receiving marked packets resp. marking them on switch side in DCTCP is the use of ECN. RFC3168 describes a mechanism for using Explicit Congestion Notification from the switch for early detection of congestion, rather than waiting for segment loss to occur. However, this method only detects the presence of congestion, not the *extent*. In the presence of mild congestion, it reduces the TCP congestion window too aggressively and unnecessarily affects the throughput of long flows [4]. DCTCP, as mentioned, enhances Explicit Congestion Notification (ECN) processing to estimate the fraction of bytes that encounter congestion, rather than simply detecting that some congestion has occurred. DCTCP then scales the TCP congestion window based on this estimate [4], thus it can derive multibit feedback from the information present in the single-bit sequence of marks in its control law. And thus act in *proportion* to the extent of congestion, not its *presence*. Switches therefore set the Congestion Experienced (CE) codepoint in packets when internal queue lengths exceed threshold K. Resulting, DCTCP delivers the same or better throughput than normal TCP, while using 90% less buffer space. It was found in [2] that DCTCP enables the applications to handle 10x the current background traffic, without impacting foreground traffic. Moreover, a 10x increase in foreground traffic did not cause any timeouts, and thus largely eliminates TCP incast collapse problems. The algorithm itself has already seen deployments in large production data centers since then. We did a long-term stress-test and analysis in a data center, short summary of our TCP incast tests with iperf compared to cubic: This test measured DCTCP throughput and latency and compared it with CUBIC throughput and latency for an incast scenario. In this test, 19 senders sent at maximum rate to a single receiver. The receiver simply ran iperf -s. The senders ran iperf -c <receiver> -t 30. All senders started simultaneously (using local clocks synchronized by ntp). This test was repeated multiple times. Below shows the results from a single test. Other tests are similar. (DCTCP results were extremely consistent, CUBIC results show some variance induced by the TCP timeouts that CUBIC encountered.) For this test, we report statistics on the number of TCP timeouts, flow throughput, and traffic latency. 1) Timeouts (total over all flows, and per flow summaries): CUBIC DCTCP Total 3227 25 Mean 169.842 1.316 Median 183 1 Max 207 5 Min 123 0 Stddev 28.991 1.600 Timeout data is taken by measuring the net change in netstat -s "other TCP timeouts" reported. As a result, the timeout measurements above are not restricted to the test traffic, and we believe that it is likely that all of the "DCTCP timeouts" are actually timeouts for non-test traffic. We report them nevertheless. CUBIC will also include some non-test timeouts, but they are drawfed by bona fide test traffic timeouts for CUBIC. Clearly DCTCP does an excellent job of preventing TCP timeouts. DCTCP reduces timeouts by at least two orders of magnitude and may well have eliminated them in this scenario. 2) Throughput (per flow in Mbps): CUBIC DCTCP Mean 521.684 521.895 Median 464 523 Max 776 527 Min 403 519 Stddev 105.891 2.601 Fairness 0.962 0.999 Throughput data was simply the average throughput for each flow reported by iperf. By avoiding TCP timeouts, DCTCP is able to achieve much better per-flow results. In CUBIC, many flows experience TCP timeouts which makes flow throughput unpredictable and unfair. DCTCP, on the other hand, provides very clean predictable throughput without incurring TCP timeouts. Thus, the standard deviation of CUBIC throughput is dramatically higher than the standard deviation of DCTCP throughput. Mean throughput is nearly identical because even though cubic flows suffer TCP timeouts, other flows will step in and fill the unused bandwidth. Note that this test is something of a best case scenario for incast under CUBIC: it allows other flows to fill in for flows experiencing a timeout. Under situations where the receiver is issuing requests and then waiting for all flows to complete, flows cannot fill in for timed out flows and throughput will drop dramatically. 3) Latency (in ms): CUBIC DCTCP Mean 4.0088 0.04219 Median 4.055 0.0395 Max 4.2 0.085 Min 3.32 0.028 Stddev 0.1666 0.01064 Latency for each protocol was computed by running "ping -i 0.2 <receiver>" from a single sender to the receiver during the incast test. For DCTCP, "ping -Q 0x6 -i 0.2 <receiver>" was used to ensure that traffic traversed the DCTCP queue and was not dropped when the queue size was greater than the marking threshold. The summary statistics above are over all ping metrics measured between the single sender, receiver pair. The latency results for this test show a dramatic difference between CUBIC and DCTCP. CUBIC intentionally overflows the switch buffer which incurs the maximum queue latency (more buffer memory will lead to high latency.) DCTCP, on the other hand, deliberately attempts to keep queue occupancy low. The result is a two orders of magnitude reduction of latency with DCTCP - even with a switch with relatively little RAM. Switches with larger amounts of RAM will incur increasing amounts of latency for CUBIC, but not for DCTCP. 4) Convergence and stability test: This test measured the time that DCTCP took to fairly redistribute bandwidth when a new flow commences. It also measured DCTCP's ability to remain stable at a fair bandwidth distribution. DCTCP is compared with CUBIC for this test. At the commencement of this test, a single flow is sending at maximum rate (near 10 Gbps) to a single receiver. One second after that first flow commences, a new flow from a distinct server begins sending to the same receiver as the first flow. After the second flow has sent data for 10 seconds, the second flow is terminated. The first flow sends for an additional second. Ideally, the bandwidth would be evenly shared as soon as the second flow starts, and recover as soon as it stops. The results of this test are shown below. Note that the flow bandwidth for the two flows was measured near the same time, but not simultaneously. DCTCP performs nearly perfectly within the measurement limitations of this test: bandwidth is quickly distributed fairly between the two flows, remains stable throughout the duration of the test, and recovers quickly. CUBIC, in contrast, is slow to divide the bandwidth fairly, and has trouble remaining stable. CUBIC DCTCP Seconds Flow 1 Flow 2 Seconds Flow 1 Flow 2 0 9.93 0 0 9.92 0 0.5 9.87 0 0.5 9.86 0 1 8.73 2.25 1 6.46 4.88 1.5 7.29 2.8 1.5 4.9 4.99 2 6.96 3.1 2 4.92 4.94 2.5 6.67 3.34 2.5 4.93 5 3 6.39 3.57 3 4.92 4.99 3.5 6.24 3.75 3.5 4.94 4.74 4 6 3.94 4 5.34 4.71 4.5 5.88 4.09 4.5 4.99 4.97 5 5.27 4.98 5 4.83 5.01 5.5 4.93 5.04 5.5 4.89 4.99 6 4.9 4.99 6 4.92 5.04 6.5 4.93 5.1 6.5 4.91 4.97 7 4.28 5.8 7 4.97 4.97 7.5 4.62 4.91 7.5 4.99 4.82 8 5.05 4.45 8 5.16 4.76 8.5 5.93 4.09 8.5 4.94 4.98 9 5.73 4.2 9 4.92 5.02 9.5 5.62 4.32 9.5 4.87 5.03 10 6.12 3.2 10 4.91 5.01 10.5 6.91 3.11 10.5 4.87 5.04 11 8.48 0 11 8.49 4.94 11.5 9.87 0 11.5 9.9 0 SYN/ACK ECT test: This test demonstrates the importance of ECT on SYN and SYN-ACK packets by measuring the connection probability in the presence of competing flows for a DCTCP connection attempt *without* ECT in the SYN packet. The test was repeated five times for each number of competing flows. Competing Flows 1 | 2 | 4 | 8 | 16 ------------------------------ Mean Connection Probability 1 | 0.67 | 0.45 | 0.28 | 0 Median Connection Probability 1 | 0.65 | 0.45 | 0.25 | 0 As the number of competing flows moves beyond 1, the connection probability drops rapidly. Enabling DCTCP with this patch requires the following steps: DCTCP must be running both on the sender and receiver side in your data center, i.e.: sysctl -w net.ipv4.tcp_congestion_control=dctcp Also, ECN functionality must be enabled on all switches in your data center for DCTCP to work. The default ECN marking threshold (K) heuristic on the switch for DCTCP is e.g., 20 packets (30KB) at 1Gbps, and 65 packets (~100KB) at 10Gbps (K > 1/7 * C * RTT, [4]). In above tests, for each switch port, traffic was segregated into two queues. For any packet with a DSCP of 0x01 - or equivalently a TOS of 0x04 - the packet was placed into the DCTCP queue. All other packets were placed into the default drop-tail queue. For the DCTCP queue, RED/ECN marking was enabled, here, with a marking threshold of 75 KB. More details however, we refer you to the paper [2] under section 3). There are no code changes required to applications running in user space. DCTCP has been implemented in full *isolation* of the rest of the TCP code as its own congestion control module, so that it can run without a need to expose code to the core of the TCP stack, and thus nothing changes for non-DCTCP users. Changes in the CA framework code are minimal, and DCTCP algorithm operates on mechanisms that are already available in most Silicon. The gain (dctcp_shift_g) is currently a fixed constant (1/16) from the paper, but we leave the option that it can be chosen carefully to a different value by the user. In case DCTCP is being used and ECN support on peer site is off, DCTCP falls back after 3WHS to operate in normal TCP Reno mode. ss {-4,-6} -t -i diag interface: ... dctcp wscale:7,7 rto:203 rtt:2.349/0.026 mss:1448 cwnd:2054 ssthresh:1102 ce_state 0 alpha 15 ab_ecn 0 ab_tot 735584 send 10129.2Mbps pacing_rate 20254.1Mbps unacked:1822 retrans:0/15 reordering:101 rcv_space:29200 ... dctcp-reno wscale:7,7 rto:201 rtt:0.711/1.327 ato:40 mss:1448 cwnd:10 ssthresh:1102 fallback_mode send 162.9Mbps pacing_rate 325.5Mbps rcv_rtt:1.5 rcv_space:29200 More information about DCTCP can be found in [1-4]. [1] http://simula.stanford.edu/~alizade/Site/DCTCP.html [2] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf [3] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf [4] http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00 Joint work with Florian Westphal and Glenn Judd. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-19fou: Support for foo-over-udp RX pathTom Herbert1-0/+10
This patch provides a receive path for foo-over-udp. This allows direct encapsulation of IP protocols over UDP. The bound destination port is used to map to an IP protocol, and the XFRM framework (udp_encap_rcv) is used to receive encapsulated packets. Upon reception, the encapsulation header is logically removed (pointer to transport header is advanced) and the packet is reinjected into the receive path with the IP protocol indicated by the mapping. Netlink is used to configure FOU ports. The configuration information includes the port number to bind to and the IP protocol corresponding to that port. This should support GRE/UDP (http://tools.ietf.org/html/draft-yong-tsvwg-gre-in-udp-encap-02), as will as the other IP tunneling protocols (IPIP, SIT). Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14udp: Add udp_sock_create for UDP tunnels to open listener socketTom Herbert1-0/+4
Added udp_tunnel.c which can contain some common functions for UDP tunnels. The first function in this is udp_sock_create which is used to open the listener port for a UDP tunnel. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03net: neighbour: Remove CONFIG_ARPDTim Gardner1-16/+0
This config option is superfluous in that it only guards a call to neigh_app_ns(). Enabling CONFIG_ARPD by default has no change in behavior. There will now be call to __neigh_notify() for each ARP resolution, which has no impact unless there is a user space daemon waiting to receive the notification, i.e., the case for which CONFIG_ARPD was designed anyways. Suggested-by: Eric W. Biederman <ebiederm@xmission.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Gao feng <gaofeng@cn.fujitsu.com> Cc: Joe Perches <joe@perches.com> Cc: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-04Kconfig: remove dangling references to the deleted fileJean Sacren1-8/+3
Commit 202dc3fc599c1dded235d3b448d9ca924252e354 (Documentation: remove obsolete networking/multicast.txt file) deleted the obsolete file. After the file has been removed, clean up a couple of places where references to the deleted file were made so that users wouldn't be confused when they consult the Help menu. Signed-off-by: Jean Sacren <sakiwit@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-26Tunneling: use IP Tunnel stats APIs.Pravin B Shelar1-0/+1
Use common function get calculate rtnl_link_stats64 stats. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-26IPIP: Use ip-tunneling code.Pravin B Shelar1-0/+1
Reuse common ip-tunneling code which is re-factored from GRE module. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-26GRE: Refactor GRE tunneling code.Pravin B Shelar1-0/+5
Following patch refactors GRE code into ip tunneling code and GRE specific code. Common tunneling code is moved to ip_tunnel module. ip_tunnel module is written as generic library which can be used by different tunneling implementations. ip_tunnel module contains following components: - packet xmit and rcv generic code. xmit flow looks like (gre_xmit/ipip_xmit)->ip_tunnel_xmit->ip_local_out. - hash table of all devices. - lookup for tunnel devices. - control plane operations like device create, destroy, ioctl, netlink operations code. - registration for tunneling modules, like gre, ipip etc. - define single pcpu_tstats dev->tstats. - struct tnl_ptk_info added to pass parsed tunnel packet parameters. ipip.h header is renamed to ip_tunnel.h Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-11net/ipv4: remove depends on CONFIG_EXPERIMENTALKees Cook1-10/+1
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a while now and is almost always enabled by default. As agreed during the Linux kernel summit, remove it from any "depends on" lines in Kconfigs. CC: "David S. Miller" <davem@davemloft.net> CC: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> CC: James Morris <jmorris@namei.org> CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> CC: Patrick McHardy <kaber@trash.net> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: David S. Miller <davem@davemloft.net>
2012-07-18net/ipv4: VTI support new module for ip_vti.Saurabh1-0/+11
New VTI tunnel kernel module, Kconfig and Makefile changes. Signed-off-by: Saurabh Mohan <saurabh.mohan@vyatta.com> Reviewed-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-15net: delete all instances of special processing for token ringPaul Gortmaker1-2/+2
We are going to delete the Token ring support. This removes any special processing in the core networking for token ring, (aside from net/tr.c itself), leaving the drivers and remaining tokenring support present but inert. The mass removal of the drivers and net/tr.c will be in a separate commit, so that the history of these files that we still care about won't have the giant deletion tied into their history. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-05-15xfrm: make xfrm_algo.c a moduleJan Beulich1-2/+2
By making this a standalone config option (auto-selected as needed), selecting CRYPTO from here rather than from XFRM (which is boolean) allows the core crypto code to become a module again even when XFRM=y. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-07net: Fix build regression when INET_UDP_DIAG=y and IPV6=mAnisse Astier1-1/+1
Tested-by: Anisse Astier <anisse@astier.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds1-1/+5
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: igmp: Avoid zero delay when receiving odd mixture of IGMP queries netdev: make net_device_ops const bcm63xx: make ethtool_ops const usbnet: make ethtool_ops const net: Fix build with INET disabled. net: introduce netif_addr_lock_nested() and call if when appropriate net: correct lock name in dev_[uc/mc]_sync documentations. net: sk_update_clone is only used in net/core/sock.c 8139cp: fix missing napi_gro_flush. pktgen: set correct max and min in pktgen_setup_inject() smsc911x: Unconditionally include linux/smscphy.h in smsc911x.h asix: fix infinite loop in rx_fixup() net: Default UDP and UNIX diag to 'n'. r6040: fix typo in use of MCR0 register bits net: fix sock_clone reference mismatch with tcp memcontrol
2012-01-08Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivialLinus Torvalds1-2/+0
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (53 commits) Kconfig: acpi: Fix typo in comment. misc latin1 to utf8 conversions devres: Fix a typo in devm_kfree comment btrfs: free-space-cache.c: remove extra semicolon. fat: Spelling s/obsolate/obsolete/g SCSI, pmcraid: Fix spelling error in a pmcraid_err() call tools/power turbostat: update fields in manpage mac80211: drop spelling fix types.h: fix comment spelling for 'architectures' typo fixes: aera -> area, exntension -> extension devices.txt: Fix typo of 'VMware'. sis900: Fix enum typo 'sis900_rx_bufer_status' decompress_bunzip2: remove invalid vi modeline treewide: Fix comment and string typo 'bufer' hyper-v: Update MAINTAINERS treewide: Fix typos in various parts of the kernel, and fix some comments. clockevents: drop unknown Kconfig symbol GENERIC_CLOCKEVENTS_MIGR gpio: Kconfig: drop unknown symbol 'CS5535_GPIO' leds: Kconfig: Fix typo 'D2NET_V2' sound: Kconfig: drop unknown symbol ARCH_CLPS7500 ... Fix up trivial conflicts in arch/powerpc/platforms/40x/Kconfig (some new kconfig additions, close to removed commented-out old ones)
2012-01-07net: Default UDP and UNIX diag to 'n'.David S. Miller1-1/+5
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-10udp_diag: Make it module when ipv6 is a modulePavel Emelyanov1-1/+1
Eric Dumazet reported, that when inet_diag is built-in the udp_diag also goes built-in and when ipv6 is a module the udp6 lookup symbol is not found. LD .tmp_vmlinux1 net/built-in.o: In function `udp_dump_one': udp_diag.c:(.text+0xa2b40): undefined reference to `__udp6_lib_lookup' make: *** [.tmp_vmlinux1] Erreur 1 Fix this by making udp diag build mode depend on both -- inet diag and ipv6. Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09udp_diag: Wire the udp_diag module into kbuildPavel Emelyanov1-0/+4
Copy-s/tcp/udp/-paste from TCP bits. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-31Kconfig: remove a few puzzling commentsPaul Bolle1-2/+0
These comments mention CONFIG options that do not exist: not as a symbol in a Kconfig file (without the CONFIG_ prefix) and neither as a symbol (with that prefix) in the code. There's one reference to XSCALE_PMU_TIMER as a negative dependency. But XSCALE_PMU_TIMER is never defined (CONFIG_XSCALE_PMU_TIMER is also unused in the code). It shows up with type "unknown" if you search for it in menuconfig. Apparently a negative dependency on an unknown symbol is always true. That negative dependency can be removed too. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-02-01ipv4: Remove fib_hash.David S. Miller1-37/+1
The time has finally come to remove the hash based routing table implementation in ipv4. FIB Trie is mature, well tested, and I've done an audit of it's code to confirm that it implements insert, delete, and lookup with the same identical semantics as fib_hash did. If there are any semantic differences found in fib_trie, we should simply fix them. I've placed the trie statistic config option under advanced router configuration. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Stephen Hemminger <shemminger@vyatta.com>
2011-01-19Merge branch 'master' of /repos/git/net-next-2.6Patrick McHardy1-1/+3
2011-01-14netfilter: fix Kconfig dependenciesPatrick McHardy1-1/+3
Fix dependencies of netfilter realm match: it depends on NET_CLS_ROUTE, which itself depends on NET_SCHED; this dependency is missing from netfilter. Since matching on realms is also useful without having NET_SCHED enabled and the option really only controls whether the tclassid member is included in route and dst entries, rename the config option to IP_ROUTE_CLASSID and move it outside of traffic scheduling context to get rid of the NET_SCHED dependeny. Reported-by: Vladis Kletnieks <Valdis.Kletnieks@vt.edu> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-11-15Docs/Kconfig: Update: osdl.org -> linuxfoundation.orgMichael Witten1-1/+3
Some of the documentation refers to web pages under the domain `osdl.org'. However, `osdl.org' now redirects to `linuxfoundation.org'. Rather than rely on redirections, this patch updates the addresses appropriately; for the most part, only documentation that is meant to be current has been updated. The patch should be pretty quick to scan and check; each new web-page url was gotten by trying out the original URL in a browser and then simply copying the the redirected URL (formatting as necessary). There is some conflict as to which one of these domain names is preferred: linuxfoundation.org linux-foundation.org So, I wrote: info@linuxfoundation.org and got this reply: Message-ID: <4CE17EE6.9040807@linuxfoundation.org> Date: Mon, 15 Nov 2010 10:41:42 -0800 From: David Ames <david@linuxfoundation.org> ... linuxfoundation.org is preferred. The canonical name for our web site is www.linuxfoundation.org. Our list site is actually lists.linux-foundation.org. Regarding email linuxfoundation.org is preferred there are a few people who choose to use linux-foundation.org for their own reasons. Consequently, I used `linuxfoundation.org' for web pages and `lists.linux-foundation.org' for mailing-list web pages and email addresses; the only personal email address I updated from `@osdl.org' was that of Andrew Morton, who prefers `linux-foundation.org' according `git log'. Signed-off-by: Michael Witten <mfwitten@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-24Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivialLinus Torvalds1-2/+2
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) Update broken web addresses in arch directory. Update broken web addresses in the kernel. Revert "drivers/usb: Remove unnecessary return's from void functions" for musb gadget Revert "Fix typo: configuation => configuration" partially ida: document IDA_BITMAP_LONGS calculation ext2: fix a typo on comment in ext2/inode.c drivers/scsi: Remove unnecessary casts of private_data drivers/s390: Remove unnecessary casts of private_data net/sunrpc/rpc_pipe.c: Remove unnecessary casts of private_data drivers/infiniband: Remove unnecessary casts of private_data drivers/gpu/drm: Remove unnecessary casts of private_data kernel/pm_qos_params.c: Remove unnecessary casts of private_data fs/ecryptfs: Remove unnecessary casts of private_data fs/seq_file.c: Remove unnecessary casts of private_data arm: uengine.c: remove C99 comments arm: scoop.c: remove C99 comments Fix typo configue => configure in comments Fix typo: configuation => configuration Fix typo interrest[ing|ed] => interest[ing|ed] Fix various typos of valid in comments ... Fix up trivial conflicts in: drivers/char/ipmi/ipmi_si_intf.c drivers/usb/gadget/rndis.c net/irda/irnet/irnet_ppp.c