Commit graph

1153 commits

Author SHA1 Message Date
Jay Vosburgh
2c26d34bbc net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding
When using VXLAN tunnels and a sky2 device, I have experienced
checksum failures of the following type:

[ 4297.761899] eth0: hw csum failure
[...]
[ 4297.765223] Call Trace:
[ 4297.765224]  <IRQ>  [<ffffffff8172f026>] dump_stack+0x46/0x58
[ 4297.765235]  [<ffffffff8162ba52>] netdev_rx_csum_fault+0x42/0x50
[ 4297.765238]  [<ffffffff8161c1a0>] ? skb_push+0x40/0x40
[ 4297.765240]  [<ffffffff8162325c>] __skb_checksum_complete+0xbc/0xd0
[ 4297.765243]  [<ffffffff8168c602>] tcp_v4_rcv+0x2e2/0x950
[ 4297.765246]  [<ffffffff81666ca0>] ? ip_rcv_finish+0x360/0x360

	These are reliably reproduced in a network topology of:

container:eth0 == host(OVS VXLAN on VLAN) == bond0 == eth0 (sky2) -> switch

	When VXLAN encapsulated traffic is received from a similarly
configured peer, the above warning is generated in the receive
processing of the encapsulated packet.  Note that the warning is
associated with the container eth0.

        The skbs from sky2 have ip_summed set to CHECKSUM_COMPLETE, and
because the packet is an encapsulated Ethernet frame, the checksum
generated by the hardware includes the inner protocol and Ethernet
headers.

	The receive code is careful to update the skb->csum, except in
__dev_forward_skb, as called by dev_forward_skb.  __dev_forward_skb
calls eth_type_trans, which in turn calls skb_pull_inline(skb, ETH_HLEN)
to skip over the Ethernet header, but does not update skb->csum when
doing so.

	This patch resolves the problem by adding a call to
skb_postpull_rcsum to update the skb->csum after the call to
eth_type_trans.

Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-26 16:16:51 -05:00
Toshiaki Makita
796f2da81b net: Fix stacked vlan offload features computation
When vlan tags are stacked, it is very likely that the outer tag is stored
in skb->vlan_tci and skb->protocol shows the inner tag's vlan_proto.
Currently netif_skb_features() first looks at skb->protocol even if there
is the outer tag in vlan_tci, thus it incorrectly retrieves the protocol
encapsulated by the inner vlan instead of the inner vlan protocol.
This allows GSO packets to be passed to HW and they end up being
corrupted.

Fixes: 58e998c6d2 ("offloading: Force software GSO for multiple vlan tags.")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-24 00:08:33 -05:00
Pravin B Shelar
d0edc7bf39 mpls: Fix config check for mpls.
Fixes MPLS GSO for case when mpls is compiled as kernel module.

Fixes: 0d89d2035f ("MPLS: Add limited GSO support").
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23 23:57:30 -05:00
Herbert Xu
ceb8d5bf17 net: Rearrange loop in net_rx_action
This patch rearranges the loop in net_rx_action to reduce the
amount of jumping back and forth when reading the code.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23 23:20:21 -05:00
Herbert Xu
6bd373ebba net: Always poll at least one device in net_rx_action
We should only perform the softnet_break check after we have polled
at least one device in net_rx_action.  Otherwise a zero or negative
setting of netdev_budget can lock up the whole system.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23 23:20:21 -05:00
Herbert Xu
001ce546bb net: Detect drivers that reschedule NAPI and exhaust budget
The commit d75b1ade56 (net: less
interrupt masking in NAPI) required drivers to leave poll_list
empty if the entire budget is consumed.

We have already had two broken drivers so let's add a check for
this.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23 23:20:21 -05:00
Herbert Xu
726ce70e9e net: Move napi polling code out of net_rx_action
This patch creates a new function napi_poll and moves the napi
polling code from net_rx_action into it.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23 23:20:21 -05:00
Jason Wang
af6dabc9c7 net: drop the packet when fails to do software segmentation or header check
Commit cecda693a9 ("net: keep original skb
which only needs header checking during software GSO") keeps the original
skb for packets that only needs header check, but it doesn't drop the
packet if software segmentation or header check were failed.

Fixes cecda693a9 ("net: keep original skb which only needs header checking during software GSO")
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23 23:12:11 -05:00
Linus Torvalds
70e71ca0af Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New offloading infrastructure and example 'rocker' driver for
    offloading of switching and routing to hardware.

    This work was done by a large group of dedicated individuals, not
    limited to: Scott Feldman, Jiri Pirko, Thomas Graf, John Fastabend,
    Jamal Hadi Salim, Andy Gospodarek, Florian Fainelli, Roopa Prabhu

 2) Start making the networking operate on IOV iterators instead of
    modifying iov objects in-situ during transfers.  Thanks to Al Viro
    and Herbert Xu.

 3) A set of new netlink interfaces for the TIPC stack, from Richard
    Alpe.

 4) Remove unnecessary looping during ipv6 routing lookups, from Martin
    KaFai Lau.

 5) Add PAUSE frame generation support to gianfar driver, from Matei
    Pavaluca.

 6) Allow for larger reordering levels in TCP, which are easily
    achievable in the real world right now, from Eric Dumazet.

 7) Add a variable of napi_schedule that doesn't need to disable cpu
    interrupts, from Eric Dumazet.

 8) Use a doubly linked list to optimize neigh_parms_release(), from
    Nicolas Dichtel.

 9) Various enhancements to the kernel BPF verifier, and allow eBPF
    programs to actually be attached to sockets.  From Alexei
    Starovoitov.

10) Support TSO/LSO in sunvnet driver, from David L Stevens.

11) Allow controlling ECN usage via routing metrics, from Florian
    Westphal.

12) Remote checksum offload, from Tom Herbert.

13) Add split-header receive, BQL, and xmit_more support to amd-xgbe
    driver, from Thomas Lendacky.

14) Add MPLS support to openvswitch, from Simon Horman.

15) Support wildcard tunnel endpoints in ipv6 tunnels, from Steffen
    Klassert.

16) Do gro flushes on a per-device basis using a timer, from Eric
    Dumazet.  This tries to resolve the conflicting goals between the
    desired handling of bulk vs.  RPC-like traffic.

17) Allow userspace to ask for the CPU upon what a packet was
    received/steered, via SO_INCOMING_CPU.  From Eric Dumazet.

18) Limit GSO packets to half the current congestion window, from Eric
    Dumazet.

19) Add a generic helper so that all drivers set their RSS keys in a
    consistent way, from Eric Dumazet.

20) Add xmit_more support to enic driver, from Govindarajulu
    Varadarajan.

21) Add VLAN packet scheduler action, from Jiri Pirko.

22) Support configurable RSS hash functions via ethtool, from Eyal
    Perry.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1820 commits)
  Fix race condition between vxlan_sock_add and vxlan_sock_release
  net/macb: fix compilation warning for print_hex_dump() called with skb->mac_header
  net/mlx4: Add support for A0 steering
  net/mlx4: Refactor QUERY_PORT
  net/mlx4_core: Add explicit error message when rule doesn't meet configuration
  net/mlx4: Add A0 hybrid steering
  net/mlx4: Add mlx4_bitmap zone allocator
  net/mlx4: Add a check if there are too many reserved QPs
  net/mlx4: Change QP allocation scheme
  net/mlx4_core: Use tasklet for user-space CQ completion events
  net/mlx4_core: Mask out host side virtualization features for guests
  net/mlx4_en: Set csum level for encapsulated packets
  be2net: Export tunnel offloads only when a VxLAN tunnel is created
  gianfar: Fix dma check map error when DMA_API_DEBUG is enabled
  cxgb4/csiostor: Don't use MASTER_MUST for fw_hello call
  net: fec: only enable mdio interrupt before phy device link up
  net: fec: clear all interrupt events to support i.MX6SX
  net: fec: reset fep link status in suspend function
  net: sock: fix access via invalid file descriptor
  net: introduce helper macro for_each_cmsghdr
  ...
2014-12-11 14:27:06 -08:00
Alexander Duyck
fd11a83dd3 net: Pull out core bits of __netdev_alloc_skb and add __napi_alloc_skb
This change pulls the core functionality out of __netdev_alloc_skb and
places them in a new function named __alloc_rx_skb.  The reason for doing
this is to make these bits accessible to a new function __napi_alloc_skb.
In addition __alloc_rx_skb now has a new flags value that is used to
determine which page frag pool to allocate from.  If the SKB_ALLOC_NAPI
flag is set then the NAPI pool is used.  The advantage of this is that we
do not have to use local_irq_save/restore when accessing the NAPI pool from
NAPI context.

In my test setup I saw at least 11ns of savings using the napi_alloc_skb
function versus the netdev_alloc_skb function, most of this being due to
the fact that we didn't have to call local_irq_save/restore.

The main use case for napi_alloc_skb would be for things such as copybreak
or page fragment based receive paths where an skb is allocated after the
data has been received instead of before.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-10 13:31:57 -05:00
Li RongQing
e008f3f07f net: avoid to call skb_queue_len again
the queue length of sd->input_pkt_queue has been put into qlen,
and impossible to change, since hold the lock

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 17:03:19 -05:00
Mahesh Bandewar
395eea6ccf rtnetlink: delay RTM_DELLINK notification until after ndo_uninit()
The commit 56bfa7ee7c ("unregister_netdevice : move RTM_DELLINK to
until after ndo_uninit") tried to do this ealier but while doing so
it created a problem. Unfortunately the delayed rtmsg_ifinfo() also
delayed call to fill_info(). So this translated into asking driver
to remove private state and then query it's private state. This
could have catastropic consequences.

This change breaks the rtmsg_ifinfo() into two parts - one takes the
precise snapshot of the device by called fill_info() before calling
the ndo_uninit() and the second part sends the notification using
collected snapshot.

It was brought to notice when last link is deleted from an ipvlan device
when it has free-ed the port and the subsequent .fill_info() call is
trying to get the info from the port.

kernel: [  255.139429] ------------[ cut here ]------------
kernel: [  255.139439] WARNING: CPU: 12 PID: 11173 at net/core/rtnetlink.c:2238 rtmsg_ifinfo+0x100/0x110()
kernel: [  255.139493] Modules linked in: ipvlan bonding w1_therm ds2482 wire cdc_acm ehci_pci ehci_hcd i2c_dev i2c_i801 i2c_core msr cpuid bnx2x ptp pps_core mdio libcrc32c
kernel: [  255.139513] CPU: 12 PID: 11173 Comm: ip Not tainted 3.18.0-smp-DEV #167
kernel: [  255.139514] Hardware name: Intel RML,PCH/Ibis_QC_18, BIOS 1.0.10 05/15/2012
kernel: [  255.139515]  0000000000000009 ffff880851b6b828 ffffffff815d87f4 00000000000000e0
kernel: [  255.139516]  0000000000000000 ffff880851b6b868 ffffffff8109c29c 0000000000000000
kernel: [  255.139518]  00000000ffffffa6 00000000000000d0 ffffffff81aaf580 0000000000000011
kernel: [  255.139520] Call Trace:
kernel: [  255.139527]  [<ffffffff815d87f4>] dump_stack+0x46/0x58
kernel: [  255.139531]  [<ffffffff8109c29c>] warn_slowpath_common+0x8c/0xc0
kernel: [  255.139540]  [<ffffffff8109c2ea>] warn_slowpath_null+0x1a/0x20
kernel: [  255.139544]  [<ffffffff8150d570>] rtmsg_ifinfo+0x100/0x110
kernel: [  255.139547]  [<ffffffff814f78b5>] rollback_registered_many+0x1d5/0x2d0
kernel: [  255.139549]  [<ffffffff814f79cf>] unregister_netdevice_many+0x1f/0xb0
kernel: [  255.139551]  [<ffffffff8150acab>] rtnl_dellink+0xbb/0x110
kernel: [  255.139553]  [<ffffffff8150da90>] rtnetlink_rcv_msg+0xa0/0x240
kernel: [  255.139557]  [<ffffffff81329283>] ? rhashtable_lookup_compare+0x43/0x80
kernel: [  255.139558]  [<ffffffff8150d9f0>] ? __rtnl_unlock+0x20/0x20
kernel: [  255.139562]  [<ffffffff8152cb11>] netlink_rcv_skb+0xb1/0xc0
kernel: [  255.139563]  [<ffffffff8150a495>] rtnetlink_rcv+0x25/0x40
kernel: [  255.139565]  [<ffffffff8152c398>] netlink_unicast+0x178/0x230
kernel: [  255.139567]  [<ffffffff8152c75f>] netlink_sendmsg+0x30f/0x420
kernel: [  255.139571]  [<ffffffff814e0b0c>] sock_sendmsg+0x9c/0xd0
kernel: [  255.139575]  [<ffffffff811d1d7f>] ? rw_copy_check_uvector+0x6f/0x130
kernel: [  255.139577]  [<ffffffff814e11c9>] ? copy_msghdr_from_user+0x139/0x1b0
kernel: [  255.139578]  [<ffffffff814e1774>] ___sys_sendmsg+0x304/0x310
kernel: [  255.139581]  [<ffffffff81198723>] ? handle_mm_fault+0xca3/0xde0
kernel: [  255.139585]  [<ffffffff811ebc4c>] ? destroy_inode+0x3c/0x70
kernel: [  255.139589]  [<ffffffff8108e6ec>] ? __do_page_fault+0x20c/0x500
kernel: [  255.139597]  [<ffffffff811e8336>] ? dput+0xb6/0x190
kernel: [  255.139606]  [<ffffffff811f05f6>] ? mntput+0x26/0x40
kernel: [  255.139611]  [<ffffffff811d2b94>] ? __fput+0x174/0x1e0
kernel: [  255.139613]  [<ffffffff814e2129>] __sys_sendmsg+0x49/0x90
kernel: [  255.139615]  [<ffffffff814e2182>] SyS_sendmsg+0x12/0x20
kernel: [  255.139617]  [<ffffffff815df092>] system_call_fastpath+0x12/0x17
kernel: [  255.139619] ---[ end trace 5e6703e87d984f6b ]---

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reported-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 13:36:57 -05:00
Jiri Pirko
02637fce3e net: rename netdev_phys_port_id to more generic name
So this can be reused for identification of other "items" as well.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Reviewed-by: Thomas Graf <tgraf@suug.ch>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-02 20:01:19 -08:00
Jiri Pirko
5968250c86 vlan: introduce *vlan_hwaccel_push_inside helpers
Use them to push skb->vlan_tci into the payload and avoid code
duplication.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-21 14:20:17 -05:00
Jiri Pirko
62749e2cb3 vlan: rename __vlan_put_tag to vlan_insert_tag_set_proto
Name fits better. Plus there's going to be introduced
__vlan_insert_tag later on.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-21 14:20:17 -05:00
Ingo Molnar
e9ac5f0fa8 Merge branch 'sched/urgent' into sched/core, to pick up fixes before applying more changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-16 10:50:25 +01:00
Michal Kubeček
fbe168ba91 net: generic dev_disable_lro() stacked device handling
Large receive offloading is known to cause problems if received packets
are passed to other host. Therefore the kernel disables it by calling
dev_disable_lro() whenever a network device is enslaved in a bridge or
forwarding is enabled for it (or globally). For virtual devices we need
to disable LRO on the underlying physical device (which is actually
receiving the packets).

Current dev_disable_lro() code handles this  propagation for a vlan
(including 802.1ad nested vlan), macvlan or a vlan on top of a macvlan.
It doesn't handle other stacked devices and their combinations, in
particular propagation from a bond to its slaves which often causes
problems in virtualization setups.

As we now have generic data structures describing the upper-lower device
relationship, dev_disable_lro() can be generalized to disable LRO also
for all lower devices (if any) once it is disabled for the device
itself.

For bonding and teaming devices, it is necessary to disable LRO not only
on current slaves at the moment when dev_disable_lro() is called but
also on any slave (port) added later.

v2: use lower device links for all devices (including vlan and macvlan)

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Veaceslav Falico <vfalico@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13 14:48:56 -05:00
Eric Dumazet
3b47d30396 net: gro: add a per device gro flush timer
Tuning coalescing parameters on NIC can be really hard.

Servers can handle both bulk and RPC like traffic, with conflicting
goals : bulk flows want as big GRO packets as possible, RPC want minimal
latencies.

To reach big GRO packets on 10Gbe NIC, one can use :

ethtool -C eth0 rx-usecs 4 rx-frames 44

But this penalizes rpc sessions, with an increase of latencies, up to
50% in some cases, as NICs generally do not force an interrupt when
a packet with TCP Push flag is received.

Some NICs do not have an absolute timer, only a timer rearmed for every
incoming packet.

This patch uses a different strategy : Let GRO stack decides what do do,
based on traffic pattern.

Packets with Push flag wont be delayed.
Packets without Push flag might be held in GRO engine, if we keep
receiving data.

This new mechanism is off by default, and shall be enabled by setting
/sys/class/net/ethX/gro_flush_timeout to a value in nanosecond.

To fully enable this mechanism, drivers should use napi_complete_done()
instead of napi_complete().

Tested:
 Ran 200 netperf TCP_STREAM from A to B (10Gbe mlx4 link, 8 RX queues)

Without this feature, we send back about 305,000 ACK per second.

GRO aggregation ratio is low (811/305 = 2.65 segments per GRO packet)

Setting a timer of 2000 nsec is enough to increase GRO packet sizes
and reduce number of ACK packets. (811/19.2 = 42)

Receiver performs less calls to upper stacks, less wakes up.
This also reduces cpu usage on the sender, as it receives less ACK
packets.

Note that reducing number of wakes up increases cpu efficiency, but can
decrease QPS, as applications wont have the chance to warmup cpu caches
doing a partial read of RPC requests/answers if they fit in one skb.

B:~# sar -n DEV 1 10 | grep eth0 | tail -1
Average:         eth0 811269.80 305732.30 1199462.57  19705.72      0.00
0.00      0.50

B:~# echo 2000 >/sys/class/net/eth0/gro_flush_timeout

B:~# sar -n DEV 1 10 | grep eth0 | tail -1
Average:         eth0 811577.30  19230.80 1199916.51   1239.80      0.00
0.00      0.50

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-10 12:05:59 -05:00
Simon Horman
25cd9ba0ab openvswitch: Add basic MPLS support to kernel
Allow datapath to recognize and extract MPLS labels into flow keys
and execute actions which push, pop, and set labels on packets.

Based heavily on work by Leo Alterman, Ravi K, Isaku Yamahata and Joe Stringer.

Cc: Ravi K <rkerur@gmail.com>
Cc: Leo Alterman <lalterman@nicira.com>
Cc: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-11-05 23:52:33 -08:00
Peter Zijlstra
ff960a7317 netdev, sched/wait: Fix sleeping inside wait event
rtnl_lock_unregistering*() take rtnl_lock() -- a mutex -- inside a
wait loop. The wait loop relies on current->state to function, but so
does mutex_lock(), nesting them makes for the inner to destroy the
outer state.

Fix this using the new wait_woken() bits.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cong Wang <cwang@twopensource.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jerry Chu <hkchu@google.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: sfeldma@cumulusnetworks.com <sfeldma@cumulusnetworks.com>
Cc: stephen hemminger <stephen@networkplumber.org>
Cc: Tom Gundersen <teg@jklm.no>
Cc: Tom Herbert <therbert@google.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Vlad Yasevich <vyasevic@redhat.com>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20141029173110.GE15602@worktop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-04 07:17:48 +01:00
Eric Dumazet
d75b1ade56 net: less interrupt masking in NAPI
net_rx_action() can mask irqs a single time to transfert sd->poll_list
into a private list, for a very short duration.

Then, napi_complete() can avoid masking irqs again,
and net_rx_action() only needs to mask irq again in slow path.

This patch removes 2 couples of irq mask/unmask per typical NAPI run,
more if multiple napi were triggered.

Note this also allows to give control back to caller (do_softirq())
more often, so that other softirq handlers can be called a bit earlier,
or ksoftirqd can be wakeup earlier under pressure.

This was developed while testing an alternative to RX interrupt
mitigation to reduce latencies while keeping or improving GRO
aggregation on fast NIC.

Idea is to test napi->gro_list at the end of a napi->poll() and
reschedule one NAPI poll, but after servicing a full round of
softirqs (timers, TX, rcu, ...). This will be allowed only if softirq
is currently serviced by idle task or ksoftirqd, and resched not needed.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-03 12:25:09 -05:00
David S. Miller
55b42b5ca2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/phy/marvell.c

Simple overlapping changes in drivers/net/phy/marvell.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-01 14:53:27 -04:00
Eric Dumazet
bc9ad166e3 net: introduce napi_schedule_irqoff()
napi_schedule() can be called from any context and has to mask hard
irqs.

Add a variant that can only be called from hard interrupts handlers
or when irqs are already masked.

Many NIC drivers can use it from their hard IRQ handler instead of
generic variant.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-29 16:07:27 -04:00
Eric Dumazet
93a35f59f1 net: napi_reuse_skb() should check pfmemalloc
Do not reuse skb if it was pfmemalloc tainted, otherwise
future frame might be dropped anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-26 22:47:23 -04:00
Linus Torvalds
2e923b0251 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Include fixes for netrom and dsa (Fabian Frederick and Florian
    Fainelli)

 2) Fix FIXED_PHY support in stmmac, from Giuseppe CAVALLARO.

 3) Several SKB use after free fixes (vxlan, openvswitch, vxlan,
    ip_tunnel, fou), from Li ROngQing.

 4) fec driver PTP support fixes from Luwei Zhou and Nimrod Andy.

 5) Use after free in virtio_net, from Michael S Tsirkin.

 6) Fix flow mask handling for megaflows in openvswitch, from Pravin B
    Shelar.

 7) ISDN gigaset and capi bug fixes from Tilman Schmidt.

 8) Fix route leak in ip_send_unicast_reply(), from Vasily Averin.

 9) Fix two eBPF JIT bugs on x86, from Alexei Starovoitov.

10) TCP_SKB_CB() reorganization caused a few regressions, fixed by Cong
    Wang and Eric Dumazet.

11) Don't overwrite end of SKB when parsing malformed sctp ASCONF
    chunks, from Daniel Borkmann.

12) Don't call sock_kfree_s() with NULL pointers, this function also has
    the side effect of adjusting the socket memory usage.  From Cong Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (90 commits)
  bna: fix skb->truesize underestimation
  net: dsa: add includes for ethtool and phy_fixed definitions
  openvswitch: Set flow-key members.
  netrom: use linux/uaccess.h
  dsa: Fix conversion from host device to mii bus
  tipc: fix bug in bundled buffer reception
  ipv6: introduce tcp_v6_iif()
  sfc: add support for skb->xmit_more
  r8152: return -EBUSY for runtime suspend
  ipv4: fix a potential use after free in fou.c
  ipv4: fix a potential use after free in ip_tunnel_core.c
  hyperv: Add handling of IP header with option field in netvsc_set_hash()
  openvswitch: Create right mask with disabled megaflows
  vxlan: fix a free after use
  openvswitch: fix a use after free
  ipv4: dst_entry leak in ip_send_unicast_reply()
  ipv4: clean up cookie_v4_check()
  ipv4: share tcp_v4_save_options() with cookie_v4_check()
  ipv4: call __ip_options_echo() in cookie_v4_check()
  atm: simplify lanai.c by using module_pci_driver
  ...
2014-10-18 09:31:37 -07:00
Tom Herbert
04ffcb255f net: Add ndo_gso_check
Add ndo_gso_check which a device can define to indicate whether is
is capable of doing GSO on a packet. This funciton would be called from
the stack to determine whether software GSO is needed to be done. A
driver should populate this function if it advertises GSO types for
which there are combinations that it wouldn't be able to handle. For
instance a device that performs UDP tunneling might only implement
support for transparent Ethernet bridging type of inner packets
or might have limitations on lengths of inner headers.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-15 12:11:00 -04:00
Linus Torvalds
0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Linus Torvalds
35a9ad8af0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Most notable changes in here:

   1) By far the biggest accomplishment, thanks to a large range of
      contributors, is the addition of multi-send for transmit.  This is
      the result of discussions back in Chicago, and the hard work of
      several individuals.

      Now, when the ->ndo_start_xmit() method of a driver sees
      skb->xmit_more as true, it can choose to defer the doorbell
      telling the driver to start processing the new TX queue entires.

      skb->xmit_more means that the generic networking is guaranteed to
      call the driver immediately with another SKB to send.

      There is logic added to the qdisc layer to dequeue multiple
      packets at a time, and the handling mis-predicted offloads in
      software is now done with no locks held.

      Finally, pktgen is extended to have a "burst" parameter that can
      be used to test a multi-send implementation.

      Several drivers have xmit_more support: i40e, igb, ixgbe, mlx4,
      virtio_net

      Adding support is almost trivial, so export more drivers to
      support this optimization soon.

      I want to thank, in no particular or implied order, Jesper
      Dangaard Brouer, Eric Dumazet, Alexander Duyck, Tom Herbert, Jamal
      Hadi Salim, John Fastabend, Florian Westphal, Daniel Borkmann,
      David Tat, Hannes Frederic Sowa, and Rusty Russell.

   2) PTP and timestamping support in bnx2x, from Michal Kalderon.

   3) Allow adjusting the rx_copybreak threshold for a driver via
      ethtool, and add rx_copybreak support to enic driver.  From
      Govindarajulu Varadarajan.

   4) Significant enhancements to the generic PHY layer and the bcm7xxx
      driver in particular (EEE support, auto power down, etc.) from
      Florian Fainelli.

   5) Allow raw buffers to be used for flow dissection, allowing drivers
      to determine the optimal "linear pull" size for devices that DMA
      into pools of pages.  The objective is to get exactly the
      necessary amount of headers into the linear SKB area pre-pulled,
      but no more.  The new interface drivers use is eth_get_headlen().
      From WANG Cong, with driver conversions (several had their own
      by-hand duplicated implementations) by Alexander Duyck and Eric
      Dumazet.

   6) Support checksumming more smoothly and efficiently for
      encapsulations, and add "foo over UDP" facility.  From Tom
      Herbert.

   7) Add Broadcom SF2 switch driver to DSA layer, from Florian
      Fainelli.

   8) eBPF now can load programs via a system call and has an extensive
      testsuite.  Alexei Starovoitov and Daniel Borkmann.

   9) Major overhaul of the packet scheduler to use RCU in several major
      areas such as the classifiers and rate estimators.  From John
      Fastabend.

  10) Add driver for Intel FM10000 Ethernet Switch, from Alexander
      Duyck.

  11) Rearrange TCP_SKB_CB() to reduce cache line misses, from Eric
      Dumazet.

  12) Add Datacenter TCP congestion control algorithm support, From
      Florian Westphal.

  13) Reorganize sk_buff so that __copy_skb_header() is significantly
      faster.  From Eric Dumazet"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1558 commits)
  netlabel: directly return netlbl_unlabel_genl_init()
  net: add netdev_txq_bql_{enqueue, complete}_prefetchw() helpers
  net: description of dma_cookie cause make xmldocs warning
  cxgb4: clean up a type issue
  cxgb4: potential shift wrapping bug
  i40e: skb->xmit_more support
  net: fs_enet: Add NAPI TX
  net: fs_enet: Remove non NAPI RX
  r8169:add support for RTL8168EP
  net_sched: copy exts->type in tcf_exts_change()
  wimax: convert printk to pr_foo()
  af_unix: remove 0 assignment on static
  ipv6: Do not warn for informational ICMP messages, regardless of type.
  Update Intel Ethernet Driver maintainers list
  bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING
  tipc: fix bug in multicast congestion handling
  net: better IFF_XMIT_DST_RELEASE support
  net/mlx4_en: remove NETDEV_TX_BUSY
  3c59x: fix bad split of cpu_to_le32(pci_map_single())
  net: bcmgenet: fix Tx ring priority programming
  ...
2014-10-08 21:40:54 -04:00
Linus Torvalds
d0cd84817c dmaengine-3.17
1/ Step down as dmaengine maintainer see commit 08223d80df "dmaengine
    maintainer update"
 
 2/ Removal of net_dma, as it has been marked 'broken' since 3.13 (commit
    7787380336 "net_dma: mark broken"), without reports of performance
    regression.
 
 3/ Miscellaneous fixes
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Merge tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine

Pull dmaengine updates from Dan Williams:
 "Even though this has fixes marked for -stable, given the size and the
  needed conflict resolutions this is 3.18-rc1/merge-window material.

  These patches have been languishing in my tree for a long while.  The
  fact that I do not have the time to do proper/prompt maintenance of
  this tree is a primary factor in the decision to step down as
  dmaengine maintainer.  That and the fact that the bulk of drivers/dma/
  activity is going through Vinod these days.

  The net_dma removal has not been in -next.  It has developed simple
  conflicts against mainline and net-next (for-3.18).

  Continuing thanks to Vinod for staying on top of drivers/dma/.

  Summary:

   1/ Step down as dmaengine maintainer see commit 08223d80df
      "dmaengine maintainer update"

   2/ Removal of net_dma, as it has been marked 'broken' since 3.13
      (commit 7787380336 "net_dma: mark broken"), without reports of
      performance regression.

   3/ Miscellaneous fixes"

* tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  net: make tcp_cleanup_rbuf private
  net_dma: revert 'copied_early'
  net_dma: simple removal
  dmaengine maintainer update
  dmatest: prevent memory leakage on error path in thread
  ioat: Use time_before_jiffies()
  dmaengine: fix xor sources continuation
  dma: mv_xor: Rename __mv_xor_slot_cleanup() to mv_xor_slot_cleanup()
  dma: mv_xor: Remove all callers of mv_xor_slot_cleanup()
  dma: mv_xor: Remove unneeded mv_xor_clean_completed_slots() call
  ioat: Use pci_enable_msix_exact() instead of pci_enable_msix()
  drivers: dma: Include appropriate header file in dca.c
  drivers: dma: Mark functions as static in dma_v3.c
  dma: mv_xor: Add DMA API error checks
  ioat/dca: Use dev_is_pci() to check whether it is pci device
2014-10-07 20:39:25 -04:00
Eric Dumazet
0287587884 net: better IFF_XMIT_DST_RELEASE support
Testing xmit_more support with netperf and connected UDP sockets,
I found strange dst refcount false sharing.

Current handling of IFF_XMIT_DST_RELEASE is not optimal.

Dropping dst in validate_xmit_skb() is certainly too late in case
packet was queued by cpu X but dequeued by cpu Y

The logical point to take care of drop/force is in __dev_queue_xmit()
before even taking qdisc lock.

As Julian Anastasov pointed out, need for skb_dst() might come from some
packet schedulers or classifiers.

This patch adds new helper to cleanly express needs of various drivers
or qdiscs/classifiers.

Drivers that need skb_dst() in their ndo_start_xmit() should call
following helper in their setup instead of the prior :

	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
->
	netif_keep_dst(dev);

Instead of using a single bit, we use two bits, one being
eventually rebuilt in bonding/team drivers.

The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being
rebuilt in bonding/team. Eventually, we could add something
smarter later.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07 13:22:11 -04:00
Eric Dumazet
1ff0dc9499 net: validate_xmit_vlan() is static
Marking this as static allows compiler to inline it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06 18:17:17 -04:00
Eric Dumazet
fcbeb976d7 net: introduce netdevice gso_min_segs attribute
Some TSO engines might have a too heavy setup cost, that impacts
performance on hosts sending small bursts (2 MSS per packet).

This patch adds a device gso_min_segs, allowing drivers to set
a minimum segment size for TSO packets, according to the NIC
performance.

Tested on a mlx4 NIC, this allows to get a ~110% increase of
throughput when sending 2 MSS per packet.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06 17:56:28 -04:00
Eric Dumazet
bec3cfdca3 net: skb_segment() provides list head and tail
Its unfortunate we have to walk again skb list to find the tail
after segmentation, even if data is probably hot in cpu caches.

skb_segment() can store the tail of the list into segs->prev,
and validate_xmit_skb_list() can immediately get the tail.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06 00:37:30 -04:00
Eric Dumazet
55a93b3ea7 qdisc: validate skb without holding lock
Validation of skb can be pretty expensive :

GSO segmentation and/or checksum computations.

We can do this without holding qdisc lock, so that other cpus
can queue additional packets.

Trick is that requeued packets were already validated, so we carry
a boolean so that sch_direct_xmit() can validate a fresh skb list,
or directly use an old one.

Tested on 40Gb NIC (8 TX queues) and 200 concurrent flows, 48 threads
host.

Turning TSO on or off had no effect on throughput, only few more cpu
cycles. Lock contention on qdisc lock disappeared.

Same if disabling TX checksum offload.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-03 15:36:11 -07:00
Dan Williams
7bced39751 net_dma: simple removal
Per commit "77873803363c net_dma: mark broken" net_dma is no longer used
and there is no plan to fix it.

This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards.
Reverting the remainder of the net_dma induced changes is deferred to
subsequent patches.

Marked for stable due to Roman's report of a memory leak in
dma_pin_iovec_pages():

    https://lkml.org/lkml/2014/9/3/177

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: David Whipple <whipple@securedatainnovations.ch>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: <stable@vger.kernel.org>
Reported-by: Roman Gushchin <klamm@yandex-team.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2014-09-28 07:05:16 -07:00
Joe Perches
6ea754eb76 net: Change netdev_<level> logging functions to return void
No caller or macro uses the return value so make all
the functions return void.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26 15:17:17 -04:00
Tom Herbert
53e5039896 net: Remove gso_send_check as an offload callback
The send_check logic was only interesting in cases of TCP offload and
UDP UFO where the checksum needed to be initialized to the pseudo
header checksum. Now we've moved that logic into the related
gso_segment functions so gso_send_check is no longer needed.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26 00:22:47 -04:00
David S. Miller
1f6d80358d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	arch/mips/net/bpf_jit.c
	drivers/net/can/flexcan.c

Both the flexcan and MIPS bpf_jit conflicts were cases of simple
overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-23 12:09:27 -04:00
Jason Wang
cecda693a9 net: keep original skb which only needs header checking during software GSO
Commit ce93718fb7 ("net: Don't keep
around original SKB when we software segment GSO frames") frees the
original skb after software GSO even for dodgy gso skbs. This breaks
the stream throughput from untrusted sources, since only header
checking was done during software GSO instead of a true
segmentation. This patch fixes this by freeing the original gso skb
only when it was really segmented by software.

Fixes ce93718fb7 ("net: Don't keep
around original SKB when we software segment GSO frames.")

Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-22 14:57:08 -04:00
Alexander Y. Fomichev
7ce64c79c4 net: fix creation adjacent device symlinks
__netdev_adjacent_dev_insert may add adjust device of different net
namespace, without proper check it leads to emergence of broken
sysfs links from/to devices in another namespace.
Fix: rewrite netdev_adjacent_is_neigh_list macro as a function,
     move net_eq check into netdev_adjacent_is_neigh_list.
     (thanks David)
     related to: 4c75431ac3

Signed-off-by: Alexander Fomichev <git.user@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15 14:24:53 -04:00
WANG Cong
6c555490e0 ipv6: drop useless rcu_read_lock() in anycast
These code is now protected by rtnl lock, rcu read lock
is useless now.

Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 16:38:42 -04:00
John Fastabend
46e5da40ae net: qdisc: use rcu prefix and silence sparse warnings
Add __rcu notation to qdisc handling by doing this we can make
smatch output more legible. And anyways some of the cases should
be using rcu_dereference() see qdisc_all_tx_empty(),
qdisc_tx_chainging(), and so on.

Also *wake_queue() API is commonly called from driver timer routines
without rcu lock or rtnl lock. So I added rcu_read_lock() blocks
around netif_wake_subqueue and netif_tx_wake_queue.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:25 -04:00
David S. Miller
eb84d6b604 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-09-07 21:41:53 -07:00
Jesper Dangaard Brouer
1f59533f9c qdisc: validate frames going through the direct_xmit path
In commit 50cbe9ab5f ("net: Validate xmit SKBs right when we
pull them out of the qdisc") the validation code was moved out of
dev_hard_start_xmit and into dequeue_skb.

However this overlooked the fact that we do not always enqueue
the skb onto a qdisc. First situation is if qdisc have flag
TCQ_F_CAN_BYPASS and qdisc is empty.  Second situation is if
there is no qdisc on the device, which is a common case for
software devices.

Originally spotted and inital patch by Alexander Duyck.
As a result Alex was seeing issues trying to connect to a
vhost_net interface after commit 50cbe9ab5f was applied.

Added a call to validate_xmit_skb() in __dev_xmit_skb(), in the
code path for qdiscs with TCQ_F_CAN_BYPASS flag, and in
__dev_queue_xmit() when no qdisc.

Also handle the error situation where dev_hard_start_xmit() could
return a skb list, and does not return dev_xmit_complete(rc) and
falls through to the kfree_skb(), in that situation it should
call kfree_skb_list().

Fixes:  50cbe9ab5f ("net: Validate xmit SKBs right when we pull them out of the qdisc")
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-03 20:41:42 -07:00
Tom Herbert
5a21232983 net: Support for csum_bad in skbuff
This flag indicates that an invalid checksum was detected in the
packet. __skb_mark_checksum_bad helper function was added to set this.

Checksums can be marked bad from a driver or the GRO path (the latter
is implemented in this patch). csum_bad is checked in
__skb_checksum_validate_complete (i.e. calling that when ip_summed ==
CHECKSUM_NONE).

csum_bad works in conjunction with ip_summed value. In the case that
ip_summed is CHECKSUM_NONE and csum_bad is set, this implies that the
first (or next) checksum encountered in the packet is bad. When
ip_summed is CHECKSUM_UNNECESSARY, the first checksum after the last
one validated is bad. For example, if ip_summed == CHECKSUM_UNNECESSARY,
csum_level == 1, and csum_bad is set-- then the third checksum in the
packet is bad. In the normal path, the packet will be dropped when
processing the protocol layer of the bad checksum:
__skb_decr_checksum_unnecessary called twice for the good checksums
changing ip_summed to CHECKSUM_NONE so that
__skb_checksum_validate_complete is called to validate the third
checksum and that will fail since csum_bad is set.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 21:36:27 -07:00
David S. Miller
8dcda22a5d net: xmit_list() becomes dev_hard_start_xmit().
Now fundamentally we can process lists of SKBs as cheaply
as single packets.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:56 -07:00
David S. Miller
ce93718fb7 net: Don't keep around original SKB when we software segment GSO frames.
Just maintain the list properly by returning the head of the remaining
SKB list from dev_hard_start_xmit().

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:56 -07:00
David S. Miller
50cbe9ab5f net: Validate xmit SKBs right when we pull them out of the qdisc.
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:56 -07:00
David S. Miller
eae3f88ee4 net: Separate out SKB validation logic from transmit path.
dev_hard_start_xmit() does two things, it first validates and
canonicalizes the SKB, then it actually sends it.

Make a set of helper functions for doing the first part.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:55 -07:00
David S. Miller
95f6b3dda2 net: Have xmit_list() signal more==true when appropriate.
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:55 -07:00