Commit Graph

974 Commits

Author SHA1 Message Date
Eric W. Biederman
50624c934d net: Delay default_device_exit_batch until no devices are unregistering v2
There is currently serialization network namespaces exiting and
network devices exiting as the final part of netdev_run_todo does not
happen under the rtnl_lock.  This is compounded by the fact that the
only list of devices unregistering in netdev_run_todo is local to the
netdev_run_todo.

This lack of serialization in extreme cases results in network devices
unregistering in netdev_run_todo after the loopback device of their
network namespace has been freed (making dst_ifdown unsafe), and after
the their network namespace has exited (making the NETDEV_UNREGISTER,
and NETDEV_UNREGISTER_FINAL callbacks unsafe).

Add the missing serialization by a per network namespace count of how
many network devices are unregistering and having a wait queue that is
woken up whenever the count is decreased.  The count and wait queue
allow default_device_exit_batch to wait until all of the unregistration
activity for a network namespace has finished before proceeding to
unregister the loopback device and then allowing the network namespace
to exit.

Only a single global wait queue is used because there is a single global
lock, and there is a single waiter, per network namespace wait queues
would be a waste of resources.

The per network namespace count of unregistering devices gives a
progress guarantee because the number of network devices unregistering
in an exiting network namespace must ultimately drop to zero (assuming
network device unregistration completes).

The basic logic remains the same as in v1.  This patch is now half
comment and half rtnl_lock_unregistering an expanded version of
wait_event performs no extra work in the common case where no network
devices are unregistering when we get to default_device_exit_batch.

Reported-by: Francesco Ruggeri <fruggeri@aristanetworks.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-28 15:09:15 -07:00
Veaceslav Falico
82476b3160 net: correctly interlink lower/upper devices
Currently we're linking upper devices to lower ones, which results in
upside-down relationship: upper devices seeing lower devices via its upper
lists.

Fix this by correctly linking lower devices to the upper ones.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 00:27:26 -04:00
Nicolas Dichtel
8b27f27797 skb: allow skb_scrub_packet() to be used by tunnels
This function was only used when a packet was sent to another netns. Now, it can
also be used after tunnel encapsulation or decapsulation.

Only skb_orphan() should not be done when a packet is not crossing netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 00:27:25 -04:00
Veaceslav Falico
48311f4685 net: add netdev_upper_get_next_dev_rcu(dev, iter)
This function returns the next dev in the dev->upper_dev_list after the
struct list_head **iter position, and updates *iter accordingly. Returns
NULL if there are no devices left.

Caller must hold RCU read lock.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 16:19:42 -04:00
Veaceslav Falico
620f3186ca net: remove search_list from netdev_adjacent
We already don't need it cause we see every upper/lower device in the list
already.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 16:19:42 -04:00
Veaceslav Falico
5d261913ca net: add lower_dev_list to net_device and make a full mesh
This patch adds lower_dev_list list_head to net_device, which is the same
as upper_dev_list, only for lower devices, and begins to use it in the same
way as the upper list.

It also changes the way the whole adjacent device lists work - now they
contain *all* of upper/lower devices, not only the first level. The first
level devices are distinguished by the bool neighbour field in
netdev_adjacent, also added by this patch.

There are cases when a device can be added several times to the adjacent
list, the simplest would be:

     /---- eth0.10 ---\
eth0-		       --- bond0
     \---- eth0.20 ---/

where both bond0 and eth0 'see' each other in the adjacent lists two times.
To avoid duplication of netdev_adjacent structures ref_nr is being kept as
the number of times the device was added to the list.

The 'full view' is achieved by adding, on link creation, all of the
upper_dev's upper_dev_list devices as upper devices to all of the
lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice
versa. On unlink they are removed using the same logic.

I've tested it with thousands vlans/bonds/bridges, everything works ok and
no observable lags even on a huge number of interfaces.

Memory footprint for 128 devices interconnected with each other via both
upper and lower (which is impossible, but for the comparison) lists would be:

128*128*2*sizeof(netdev_adjacent) = 1.5MB

but in the real world we usualy have at most several devices with slaves
and a lot of vlans, so the footprint will be much lower.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 16:19:42 -04:00
Veaceslav Falico
aa9d85605f net: rename netdev_upper to netdev_adjacent
Rename the structure to reflect the upcoming addition of lower_dev_list.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 16:19:41 -04:00
Nicolas Dichtel
64261f230a dev: move skb_scrub_packet() after eth_type_trans()
skb_scrub_packet() was called before eth_type_trans() to let eth_type_trans()
set pkt_type.

In fact, we should force pkt_type to PACKET_HOST, so move the call after
eth_type_trans().

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-15 01:00:20 -07:00
Jiri Pirko
66b52b0dc8 net: add ndo to get id of physical port of the device
This patch adds a ndo for getting physical port of the device. Driver
which is aware of being virtual function of some physical port should
implement this ndo. This is applicable not only for IOV, but for other
solutions (NPAR, multichannel) as well. Basically if there is possible
to have multiple netdevs on the single hw port.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-30 17:31:24 -07:00
Thomas Gleixner
18afa4b028 net: Make devnet_rename_seq static
No users outside net/core/dev.c.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-24 17:57:26 -07:00
Eric Dumazet
d4b812dea4 vlan: mask vlan prio bits
In commit 48cc32d38a
("vlan: don't deliver frames for unknown vlans to protocols")
Florian made sure we set pkt_type to PACKET_OTHERHOST
if the vlan id is set and we could find a vlan device for this
particular id.

But we also have a problem if prio bits are set.

Steinar reported an issue on a router receiving IPv6 frames with a
vlan tag of 4000 (id 0, prio 2), and tunneled into a sit device,
because skb->vlan_tci is set.

Forwarded frame is completely corrupted : We can see (8100:4000)
being inserted in the middle of IPv6 source address :

16:48:00.780413 IP6 2001:16d8:8100:4000:ee1c:0:9d9:bc87 >
9f94:4d95:2001:67c:29f4::: ICMP6, unknown icmp6 type (0), length 64
       0x0000:  0000 0029 8000 c7c3 7103 0001 a0ae e651
       0x0010:  0000 0000 ccce 0b00 0000 0000 1011 1213
       0x0020:  1415 1617 1819 1a1b 1c1d 1e1f 2021 2223
       0x0030:  2425 2627 2829 2a2b 2c2d 2e2f 3031 3233

It seems we are not really ready to properly cope with this right now.

We can probably do better in future kernels :
vlan_get_ingress_priority() should be a netdev property instead of
a per vlan_dev one.

For stable kernels, lets clear vlan_tci to fix the bugs.

Reported-by: Steinar H. Gunderson <sesse@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-18 13:05:23 -07:00
Alexander Duyck
cdbaa0bb26 gso: Update tunnel segmentation to support Tx checksum offload
This change makes it so that the GRE and VXLAN tunnels can make use of Tx
checksum offload support provided by some drivers via the hw_enc_features.
Without this fix enabling GSO means sacrificing Tx checksum offload and
this actually leads to a performance regression as shown below:

            Utilization
            Send
Throughput  local         GSO
10^6bits/s  % S           state
  6276.51   8.39          enabled
  7123.52   8.42          disabled

To resolve this it was necessary to address two items.  First
netif_skb_features needed to be updated so that it would correctly handle
the Trans Ether Bridging protocol without impacting the need to check for
Q-in-Q tagging.  To do this it was necessary to update harmonize_features
so that it used skb_network_protocol instead of just using the outer
protocol.

Second it was necessary to update the GRE and UDP tunnel segmentation
offloads so that they would reset the encapsulation bit and inner header
offsets after the offload was complete.

As a result of this change I have seen the following results on a interface
with Tx checksum enabled for encapsulated frames:

            Utilization
            Send
Throughput  local         GSO
10^6bits/s  % S           state
  7123.52   8.42          disabled
  8321.75   5.43          enabled

v2: Instead of replacing refrence to skb->protocol with
    skb_network_protocol just replace the protocol reference in
    harmonize_features to allow for double VLAN tag checks.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-11 12:18:49 -07:00
David S. Miller
0c1072ae02 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/freescale/fec_main.c
	drivers/net/ethernet/renesas/sh_eth.c
	net/ipv4/gre.c

The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list)
and the splitting of the gre.c code into seperate files.

The FEC conflict was two sets of changes adding ethtool support code
in an "!CONFIG_M5272" CPP protected block.

Finally the sh_eth.c conflict was between one commit add bits set
in the .eesr_err_check mask whilst another commit removed the
.tx_error_check member and assignments.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-03 14:55:13 -07:00
Isaku Yamahata
06a23fe31c core/dev: set pkt_type after eth_type_trans() in dev_forward_skb()
The dev_forward_skb() assignment of pkt_type should be done
after the call to eth_type_trans().

ip-encapsulated packets can be handled by localhost. But skb->pkt_type
can be PACKET_OTHERHOST when packet comes via veth into ip tunnel device.
In that case, the packet is dropped by ip_rcv().
Although this example uses gretap. l2tp-eth also has same issue.
For l2tp-eth case, add dummy device for ip address and ip l2tp command.

netns A |                     root netns                      | netns B
   veth<->veth=bridge=gretap <-loop back-> gretap=bridge=veth<->veth

arp packet ->
pkt_type
         BROADCAST------------>ip_rcv()------------------------>

                                                             <- arp reply
                                                                pkt_type
                               ip_rcv()<-----------------OTHERHOST
                               drop

sample operations
  ip link add tapa type gretap remote 172.17.107.4 local 172.17.107.3
  ip link add tapb type gretap remote 172.17.107.3 local 172.17.107.4
  ip link set tapa up
  ip link set tapb up
  ip address add 172.17.107.3 dev tapa
  ip address add 172.17.107.4 dev tapb
  ip route get 172.17.107.3
  > local 172.17.107.3 dev lo  src 172.17.107.3
  >    cache <local>
  ip route get 172.17.107.4
  > local 172.17.107.4 dev lo  src 172.17.107.4
  >    cache <local>
  ip link add vetha type veth peer name vetha-peer
  ip link add vethb type veth peer name vethb-peer
  brctl addbr bra
  brctl addbr brb
  brctl addif bra tapa
  brctl addif bra vetha-peer
  brctl addif brb tapb
  brctl addif brb vethb-peer
  brctl show
  > bridge name     bridge id               STP enabled     interfaces
  > bra             8000.6ea21e758ff1       no              tapa
  >                                                         vetha-peer
  > brb             8000.420020eb92d5       no              tapb
  >                                                         vethb-peer
  ip link set vetha-peer up
  ip link set vethb-peer up
  ip link set bra up
  ip link set brb up
  ip netns add a
  ip netns add b
  ip link set vetha netns a
  ip link set vethb netns b
  ip netns exec a ip address add 10.0.0.3/24 dev vetha
  ip netns exec b ip address add 10.0.0.4/24 dev vethb
  ip netns exec a ip link set vetha up
  ip netns exec b ip link set vethb up
  ip netns exec a arping -I vetha 10.0.0.4
  ARPING 10.0.0.4 from 10.0.0.3 vetha
  ^CSent 2 probes (2 broadcast(s))
  Received 0 response(s)

Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Hong Zhiguo <honkiko@gmail.com>
Cc: Rami Rosen <ramirose@gmail.com>
Cc: Tom Parkin <tparkin@katalix.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Cc: Jesse Gross <jesse@nicira.com>
Cc: dev@openvswitch.org
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-02 15:59:18 -07:00
Nicolas Dichtel
621e84d6f3 dev: introduce skb_scrub_packet()
The goal of this new function is to perform all needed cleanup before sending
an skb into another netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-27 22:29:05 -07:00
Nicolas Schichan
5dbe7c178d net: fix kernel deadlock with interface rename and netdev name retrieval.
When the kernel (compiled with CONFIG_PREEMPT=n) is performing the
rename of a network interface, it can end up waiting for a workqueue
to complete. If userland is able to invoke a SIOCGIFNAME ioctl or a
SO_BINDTODEVICE getsockopt in between, the kernel will deadlock due to
the fact that read_secklock_begin() will spin forever waiting for the
writer process (the one doing the interface rename) to update the
devnet_rename_seq sequence.

This patch fixes the problem by adding a helper (netdev_get_name())
and using it in the code handling the SIOCGIFNAME ioctl and
SO_BINDTODEVICE setsockopt.

The netdev_get_name() helper uses raw_seqcount_begin() to avoid
spinning forever, waiting for devnet_rename_seq->sequence to become
even. cond_resched() is used in the contended case, before retrying
the access to give the writer process a chance to finish.

The use of raw_seqcount_begin() will incur some unneeded work in the
reader process in the contended case, but this is better than
deadlocking the system.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-26 13:42:54 -07:00
Eric Dumazet
60877a32bc net: allow large number of tx queues
netif_alloc_netdev_queues() uses kcalloc() to allocate memory
for the "struct netdev_queue *_tx" array.

For large number of tx queues, kcalloc() might fail, so this
patch does a fallback to vzalloc().

As vmalloc() adds overhead on a critical network path, add __GFP_REPEAT
to kzalloc() flags to do this fallback only when really needed.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-23 23:56:55 -07:00
Eliezer Tamir
af12fa6e46 net: add napi_id and hash
Adds a napi_id and a hashing mechanism to lookup a napi by id.
This will be used by subsequent patches to implement low latency
Ethernet device polling.
Based on a code sample by Eric Dumazet.

Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 21:22:35 -07:00
Baruch Siach
430f03cde2 net: mark netdev_create_hash __net_init
netdev_create_hash() is only called from netdev_init() which is marked
__net_init.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-04 16:47:27 -07:00
Simon Horman
ced14f6804 net: Correct comparisons and calculations using skb->tail and skb-transport_header
This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer whereas skb->transport_header
will be an offset from head. This is corrected by using wrappers that
ensure that comparisons and calculations are always made using pointers.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-28 23:49:07 -07:00
Cong Wang
75538c2b85 net: always pass struct netdev_notifier_info to netdevice notifiers
commit 351638e7de (net: pass info struct via netdevice notifier)
breaks booting of my KVM guest, this is due to we still forget to pass
struct netdev_notifier_info in several places. This patch completes it.

Cc: Jiri Pirko <jiri@resnulli.us>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-28 21:58:54 -07:00
Jiri Pirko
be9efd3653 net: pass changed flags along with NETDEV_CHANGE event
Use new netdevice notifier infrastructure to pass along changed flags.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>

v2->v3: shortened notifier_info struct name
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-28 13:11:01 -07:00
Jiri Pirko
351638e7de net: pass info struct via netdevice notifier
So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
	shortened dev_getter
	shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-28 13:11:01 -07:00
dingtianhong
da6e378ba9 netpoll: remove return value from netpoll_rx_disable()
The netpoll_rx_disable() will always return 0, it is no use and looks wordy,
so remove the unnecessary code and get rid of it in _dev_open and _dev_close.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-27 23:18:50 -07:00
Simon Horman
0d89d2035f MPLS: Add limited GSO support
In the case where a non-MPLS packet is received and an MPLS stack is
added it may well be the case that the original skb is GSO but the
NIC used for transmit does not support GSO of MPLS packets.

The aim of this code is to provide GSO in software for MPLS packets
whose skbs are GSO.

SKB Usage:

When an implementation adds an MPLS stack to a non-MPLS packet it should do
the following to skb metadata:

* Set skb->inner_protocol to the old non-MPLS ethertype of the packet.
  skb->inner_protocol is added by this patch.

* Set skb->protocol to the new MPLS ethertype of the packet.

* Set skb->network_header to correspond to the
  end of the L3 header, including the MPLS label stack.

I have posted a patch, "[PATCH v3.29] datapath: Add basic MPLS support to
kernel" which adds MPLS support to the kernel datapath of Open vSwtich.
That patch sets the above requirements in datapath/actions.c:push_mpls()
and was used to exercise this code.  The datapath patch is against the Open
vSwtich tree but it is intended that it be added to the Open vSwtich code
present in the mainline Linux kernel at some point.

Features:

I believe that the approach that I have taken is at least partially
consistent with the handling of other protocols.  Jesse, I understand that
you have some ideas here.  I am more than happy to change my implementation.

This patch adds dev->mpls_features which may be used by devices
to advertise features supported for MPLS packets.

A new NETIF_F_MPLS_GSO feature is added for devices which support
hardware MPLS GSO offload.  Currently no devices support this
and MPLS GSO always falls back to software.

Alternate Implementation:

One possible alternate implementation is to teach netif_skb_features()
and skb_network_protocol() about MPLS, in a similar way to their
understanding of VLANs. I believe this would avoid the need
for net/mpls/mpls_gso.c and in particular the calls to
__skb_push() and __skb_push() in mpls_gso_segment().

I have decided on the implementation in this patch as it should
not introduce any overhead in the case where mpls_gso is not compiled
into the kernel or inserted as a module.

MPLS GSO suggested by Jesse Gross.
Based in part on "v4 GRE: Add TCP segmentation offload for GRE"
by Pravin B Shelar.

Cc: Jesse Gross <jesse@nicira.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-27 22:50:59 -07:00
Jiri Pirko
42e52bf9e3 net: add netnotifier event for upper device change
Now when upper device is changed, event is not propagated via RT Netlink
to userspace. Userspace might never now about the change. Fix this by
adding upper-device-change notifier event.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-25 23:12:19 -07:00
Willem de Bruijn
99bbc70741 rps: selective flow shedding during softnet overflow
A cpu executing the network receive path sheds packets when its input
queue grows to netdev_max_backlog. A single high rate flow (such as a
spoofed source DoS) can exceed a single cpu processing rate and will
degrade throughput of other flows hashed onto the same cpu.

This patch adds a more fine grained hashtable. If the netdev backlog
is above a threshold, IRQ cpus track the ratio of total traffic of
each flow (using 4096 buckets, configurable). The ratio is measured
by counting the number of packets per flow over the last 256 packets
from the source cpu. Any flow that occupies a large fraction of this
(set at 50%) will see packet drop while above the threshold.

Tested:
Setup is a muli-threaded UDP echo server with network rx IRQ on cpu0,
kernel receive (RPS) on cpu0 and application threads on cpus 2--7
each handling 20k req/s. Throughput halves when hit with a 400 kpps
antagonist storm. With this patch applied, antagonist overload is
dropped and the server processes its complete load.

The patch is effective when kernel receive processing is the
bottleneck. The above RPS scenario is a extreme, but the same is
reached with RFS and sufficient kernel processing (iptables, packet
socket tap, ..).

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-20 13:48:04 -07:00
Nicolas Dichtel
57b354e66b dev: remove duplicate 'skb->dev = dev' in dev_forward_skb()
This was added by commit 59b9997bab (Revert "net: maintain namespace
isolation between vlan and real device").
In fact, before the initial commit - the one that is reverted -, this
statement was not present.
'skb->dev = dev' is already done in eth_type_trans(), which is call just
after.

Spotted-by: Alain Ritoux <alain.ritoux@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-17 18:23:08 -07:00
Pravin B Shelar
19acc32725 gso: Handle Trans-Ether-Bridging protocol in skb_network_protocol()
Rather than having logic to calculate inner protocol in every
tunnel gso handler move it to gso code. This simplifies code.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Cong Wang <amwang@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-08 13:13:30 -07:00
Patrick McHardy
6708c9e5cc net: use netdev_features_t in skb_needs_linearize()
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-02 13:58:12 -04:00
Sridhar Samudrala
0c772159d1 net: Use consume_skb() to free gso segmented skb
Use consume_skb() to free the original skb that is successfully transmitted
as gso segmented skbs so that it is not treated as a drop due to an error.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-30 00:18:13 -04:00
Eric Dumazet
e12472dc57 net: remove redundant code in dev_hard_start_xmit()
This reverts commit 068a2de57d (net: release dst entry while
cache-hot for GSO case too)

Before GSO packet segmentation, we already take care of skb->dst if it
can be released.

There is no point adding extra test for every segment in the gso loop.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-25 01:38:25 -04:00
David S. Miller
6e0895c2ea Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/emulex/benet/be_main.c
	drivers/net/ethernet/intel/igb/igb_main.c
	drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
	include/net/scm.h
	net/batman-adv/routing.c
	net/ipv4/tcp_input.c

The e{uid,gid} --> {uid,gid} credentials fix conflicted with the
cleanup in net-next to now pass cred structs around.

The be2net driver had a bug fix in 'net' that overlapped with the VLAN
interface changes by Patrick McHardy in net-next.

An IGB conflict existed because in 'net' the build_skb() support was
reverted, and in 'net-next' there was a comment style fix within that
code.

Several batman-adv conflicts were resolved by making sure that all
calls to batadv_is_my_mac() are changed to have a new bat_priv first
argument.

Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO
rewrite in 'net-next', mostly overlapping changes.

Thanks to Stephen Rothwell and Antonio Quartulli for help with several
of these merge resolutions.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-22 20:32:51 -04:00
dingtianhong
53759be997 net: Remove return value from list_netdevice()
The return value from list_netdevice() is not used and no need, so remove it.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-22 16:09:24 -04:00
Ben Greear
c846ad9b88 net: rate-limit warn-bad-offload splats.
If one does do something unfortunate and allow a
bad offload bug into the kernel, this the
skb_warn_bad_offload can effectively live-lock the
system, filling the logs with the same error over
and over.

Add rate limitation to this so that box remains otherwise
functional in this case.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 17:57:49 -04:00
Patrick McHardy
8ad227ff89 net: vlan: add 802.1ad support
Add support for 802.1ad VLAN devices. This mainly consists of checking for
ETH_P_8021AD in addition to ETH_P_8021Q in a couple of places and check
offloading capabilities based on the used protocol.

Configuration is done using "ip link":

# ip link add link eth0 eth0.1000 \
	type vlan proto 802.1ad id 1000
# ip link add link eth0.1000 eth0.1000.1000 \
	type vlan proto 802.1q id 1000

52:54:00:12:34:56 > 92:b1:54:28:e4:8c, ethertype 802.1Q (0x8100), length 106: vlan 1000, p 0, ethertype 802.1Q, vlan 1000, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
    20.1.0.2 > 20.1.0.1: ICMP echo request, id 3003, seq 8, length 64
92:b1:54:28:e4:8c > 52:54:00:12:34:56, ethertype 802.1Q-QinQ (0x88a8), length 106: vlan 1000, p 0, ethertype 802.1Q, vlan 1000, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 47944, offset 0, flags [none], proto ICMP (1), length 84)
    20.1.0.1 > 20.1.0.2: ICMP echo reply, id 3003, seq 8, length 64

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 14:46:06 -04:00
Patrick McHardy
86a9bad3ab net: vlan: add protocol argument to packet tagging functions
Add a protocol argument to the VLAN packet tagging functions. In case of HW
tagging, we need that protocol available in the ndo_start_xmit functions,
so it is stored in a new field in the skb. The new field fits into a hole
(on 64 bit) and doesn't increase the sks's size.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 14:46:06 -04:00
Patrick McHardy
f646968f8f net: vlan: rename NETIF_F_HW_VLAN_* feature flags to NETIF_F_HW_VLAN_CTAG_*
Rename the hardware VLAN acceleration features to include "CTAG" to indicate
that they only support CTAGs. Follow up patches will introduce 802.1ad
server provider tagging (STAGs) and require the distinction for hardware not
supporting acclerating both.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 14:45:26 -04:00
David S. Miller
d978a6361a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/nfc/microread/mei.c
	net/netfilter/nfnetlink_queue_core.c

Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which
some cleanups are going to go on-top.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-07 18:37:01 -04:00
Patrick McHardy
124dff01af netfilter: don't reset nf_trace in nf_reset()
Commit 130549fe ("netfilter: reset nf_trace in nf_reset") added code
to reset nf_trace in nf_reset(). This is wrong and unnecessary.

nf_reset() is used in the following cases:

- when passing packets up the the socket layer, at which point we want to
  release all netfilter references that might keep modules pinned while
  the packet is queued. nf_trace doesn't matter anymore at this point.

- when encapsulating or decapsulating IPsec packets. We want to continue
  tracing these packets after IPsec processing.

- when passing packets through virtual network devices. Only devices on
  that encapsulate in IPv4/v6 matter since otherwise nf_trace is not
  used anymore. Its not entirely clear whether those packets should
  be traced after that, however we've always done that.

- when passing packets through virtual network devices that make the
  packet cross network namespace boundaries. This is the only cases
  where we clearly want to reset nf_trace and is also what the
  original patch intended to fix.

Add a new function nf_reset_trace() and use it in dev_forward_skb() to
fix this properly.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-05 15:38:10 -04:00
David S. Miller
a210576cf8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/mac80211/sta_info.c
	net/wireless/core.h

Two minor conflicts in wireless.  Overlapping additions of extern
declarations in net/wireless/core.h and a bug fix overlapping with
the addition of a boolean parameter to __ieee80211_key_free().

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-01 13:36:50 -04:00
Eric Dumazet
00cfec3748 net: add a synchronize_net() in netdev_rx_handler_unregister()
commit 35d48903e9 (bonding: fix rx_handler locking) added a race
in bonding driver, reported by Steven Rostedt who did a very good
diagnosis :

<quoting Steven>

I'm currently debugging a crash in an old 3.0-rt kernel that one of our
customers is seeing. The bug happens with a stress test that loads and
unloads the bonding module in a loop (I don't know all the details as
I'm not the one that is directly interacting with the customer). But the
bug looks to be something that may still be present and possibly present
in mainline too. It will just be much harder to trigger it in mainline.

In -rt, interrupts are threads, and can schedule in and out just like
any other thread. Note, mainline now supports interrupt threads so this
may be easily reproducible in mainline as well. I don't have the ability
to tell the customer to try mainline or other kernels, so my hands are
somewhat tied to what I can do.

But according to a core dump, I tracked down that the eth irq thread
crashed in bond_handle_frame() here:

        slave = bond_slave_get_rcu(skb->dev);
        bond = slave->bond; <--- BUG

the slave returned was NULL and accessing slave->bond caused a NULL
pointer dereference.

Looking at the code that unregisters the handler:

void netdev_rx_handler_unregister(struct net_device *dev)
{

        ASSERT_RTNL();
        RCU_INIT_POINTER(dev->rx_handler, NULL);
        RCU_INIT_POINTER(dev->rx_handler_data, NULL);
}

Which is basically:
        dev->rx_handler = NULL;
        dev->rx_handler_data = NULL;

And looking at __netif_receive_skb() we have:

        rx_handler = rcu_dereference(skb->dev->rx_handler);
        if (rx_handler) {
                if (pt_prev) {
                        ret = deliver_skb(skb, pt_prev, orig_dev);
                        pt_prev = NULL;
                }
                switch (rx_handler(&skb)) {

My question to all of you is, what stops this interrupt from happening
while the bonding module is unloading?  What happens if the interrupt
triggers and we have this:

        CPU0                    CPU1
        ----                    ----
  rx_handler = skb->dev->rx_handler

                        netdev_rx_handler_unregister() {
                           dev->rx_handler = NULL;
                           dev->rx_handler_data = NULL;

  rx_handler()
   bond_handle_frame() {
    slave = skb->dev->rx_handler;
    bond = slave->bond; <-- NULL pointer dereference!!!

What protection am I missing in the bond release handler that would
prevent the above from happening?

</quoting Steven>

We can fix bug this in two ways. First is adding a test in
bond_handle_frame() and others to check if rx_handler_data is NULL.

A second way is adding a synchronize_net() in
netdev_rx_handler_unregister() to make sure that a rcu protected reader
has the guarantee to see a non NULL rx_handler_data.

The second way is better as it avoids an extra test in fast path.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jiri Pirko <jpirko@redhat.com>
Cc: Paul E. McKenney <paulmck@us.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-29 15:38:15 -04:00
Shmulik Ladkani
a561cf7edf net: core: Remove redundant call to 'nf_reset' in 'dev_forward_skb'
'nf_reset' is called just prior calling 'netif_rx'.
No need to call it twice.

Reported-by: Igor Michailov <rgohita@gmail.com>
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-29 15:25:28 -04:00
David S. Miller
e2a553dbf1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	include/net/ipip.h

The changes made to ipip.h in 'net' were already included
in 'net-next' before that header was moved to another location.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-27 13:52:49 -04:00
Jason Wang
15e5a03071 net_sched: better precise estimation on packet length for untrusted packets
gso_segs were reset to zero when kernel receive packets from untrusted
source. But we use this zero value to estimate precise packet len which is
wrong. So this patch tries to estimate the correct gso_segs value before using
it in qdisc_pkt_len_init().

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-26 12:44:44 -04:00
Eric Dumazet
9979a55a83 net: remove a WARN_ON() in net_enable_timestamp()
The WARN_ON(in_interrupt()) in net_enable_timestamp() can get false
positive, in socket clone path, run from softirq context :

[ 3641.624425] WARNING: at net/core/dev.c:1532 net_enable_timestamp+0x7b/0x80()
[ 3641.668811] Call Trace:
[ 3641.671254]  <IRQ>  [<ffffffff80286817>] warn_slowpath_common+0x87/0xc0
[ 3641.677871]  [<ffffffff8028686a>] warn_slowpath_null+0x1a/0x20
[ 3641.683683]  [<ffffffff80742f8b>] net_enable_timestamp+0x7b/0x80
[ 3641.689668]  [<ffffffff80732ce5>] sk_clone_lock+0x425/0x450
[ 3641.695222]  [<ffffffff8078db36>] inet_csk_clone_lock+0x16/0x170
[ 3641.701213]  [<ffffffff807ae449>] tcp_create_openreq_child+0x29/0x820
[ 3641.707663]  [<ffffffff807d62e2>] ? ipt_do_table+0x222/0x670
[ 3641.713354]  [<ffffffff807aaf5b>] tcp_v4_syn_recv_sock+0xab/0x3d0
[ 3641.719425]  [<ffffffff807af63a>] tcp_check_req+0x3da/0x530
[ 3641.724979]  [<ffffffff8078b400>] ? inet_hashinfo_init+0x60/0x80
[ 3641.730964]  [<ffffffff807ade6f>] ? tcp_v4_rcv+0x79f/0xbe0
[ 3641.736430]  [<ffffffff807ab9bd>] tcp_v4_do_rcv+0x38d/0x4f0
[ 3641.741985]  [<ffffffff807ae14a>] tcp_v4_rcv+0xa7a/0xbe0

Its safe at this point because the parent socket owns a reference
on the netstamp_needed, so we cant have a 0 -> 1 transition, which
requires to lock a mutex.

Instead of refining the check, lets remove it, as all known callers
are safe. If it ever changes in the future, static_key_slow_inc()
will complain anyway.

Reported-by: Laurent Chavey <chavey@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-24 17:27:27 -04:00
David S. Miller
61816596d1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull in the 'net' tree to get Daniel Borkmann's flow dissector
infrastructure change.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20 12:46:26 -04:00
Kusanagi Kouichi
166ec36968 net: Fix a comment typo
Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-18 13:06:09 -04:00
Li RongQing
c80a8512ee net/core: move vlan_depth out of while loop in skb_network_protocol()
[ Bug added added in commit 05e8ef4ab2 (net: factor out
  skb_mac_gso_segment() from skb_gso_segment() ) ]

move vlan_depth out of while loop, or else vlan_depth always is ETH_HLEN,
can not be increased, and lead to infinite loop when frame has two vlan headers.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-12 11:47:40 -04:00
David S. Miller
e5f2ef7ab4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/intel/e1000e/netdev.c

Minor conflict in e1000e, a line that got fixed in 'net'
has been removed in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-12 05:52:22 -04:00