Commit Graph

105 Commits

Author SHA1 Message Date
Eric Dumazet fd2f473787 net: use u64_stats_t in struct pcpu_lstats
In order to fix the data-race found by KCSAN, we
can use the new u64_stats_t type and its accessors instead
of plain u64 fields. This will still generate optimal code
for both 32 and 64 bit platforms.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-07 20:03:08 -08:00
Eric Dumazet dd5382a081 net: provide dev_lstats_add() helper
Many network drivers need it and hand-coded the same function.

In order to ease u64_stats_t adoption, it is time to factorize.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-07 20:03:08 -08:00
Eric Dumazet de7d5084d8 net: provide dev_lstats_read() helper
Many network drivers use hand-coded implementation of the same thing,
let's factorize things so that u64_stats_t adoption is done once.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-07 20:03:08 -08:00
Mahesh Bandewar d62962b37c loopback: fix lockdep splat
dev_init_scheduler() and dev_activate() expect the caller to
hold RTNL. Since we don't want blackhole device to be initialized
per ns, we are initializing at init.

[    3.855027] Call Trace:
[    3.855034]  dump_stack+0x67/0x95
[    3.855037]  lockdep_rcu_suspicious+0xd5/0x110
[    3.855044]  dev_init_scheduler+0xe3/0x120
[    3.855048]  ? net_olddevs_init+0x60/0x60
[    3.855050]  blackhole_netdev_init+0x45/0x6e
[    3.855052]  do_one_initcall+0x6c/0x2fa
[    3.855058]  ? rcu_read_lock_sched_held+0x8c/0xa0
[    3.855066]  kernel_init_freeable+0x1e5/0x288
[    3.855071]  ? rest_init+0x260/0x260
[    3.855074]  kernel_init+0xf/0x180
[    3.855076]  ? rest_init+0x260/0x260
[    3.855078]  ret_from_fork+0x24/0x30

Fixes: 4de83b88c6 ("loopback: create blackhole net device similar to loopack.")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-03 11:24:38 -07:00
Mahesh Bandewar 4de83b88c6 loopback: create blackhole net device similar to loopack.
Create a blackhole net device that can be used for "dead"
dst entries instead of loopback device. This blackhole device differs
from loopback in few aspects: (a) It's not per-ns. (b)  MTU on this
device is ETH_MIN_MTU (c) The xmit function is essentially kfree_skb().
and (d) since it's not registered it won't have ifindex.

Lower MTU effectively make the device not pass the MTU check during
the route check when a dst associated with the skb is dead.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-01 19:34:46 -07:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Julian Wiedmann af730342ec net: loopback: use generic helper to report timestamping info
For reporting the common set of SW timestamping capabilities, use
ethtool_op_get_ts_info() instead of re-implementing it.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-12 16:26:37 -07:00
Eric Dumazet 4c16128b62 net: loopback: clear skb->tstamp before netif_rx()
At least UDP / TCP stacks can now cook skbs with a tstamp using
MONOTONIC base (or arbitrary values with SCM_TXTIME)

Since loopback driver does not call (directly or indirectly)
skb_scrub_packet(), we need to clear skb->tstamp so that
net_timestamp_check() can eventually resample the time,
using ktime_get_real().

Fixes: 80b14dee2b ("net: Add a new socket option for a future transmit time.")
Fixes: fb420d5d91 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-20 01:01:28 -07:00
Li RongQing 52bb6677d5 net: move definition of pcpu_lstats to header file
pcpu_lstats is defined in several files, so unify them as one
and move to header file

Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-14 08:32:23 -07:00
David S. Miller cf124db566 net: Fix inconsistent teardown and release of private netdev state.
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init().  However, the release of these resources
can occur in one of two different places.

Either netdev_ops->ndo_uninit() or netdev->destructor().

The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.

netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.

netdev->destructor(), on the other hand, does not run until the
netdev references all go away.

Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().

This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.

If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit().  But
it is not able to invoke netdev->destructor().

This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.

However, this means that the resources that would normally be released
by netdev->destructor() will not be.

Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.

Many drivers do not try to deal with this, and instead we have leaks.

Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().

netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().

netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().

Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().

And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-07 15:53:24 -04:00
Ezequiel Lara Gomez b3407c8e5e Cleanup some warning from timestamping code.
Following checkpatch.pl recommendations (which include
replacing with <linux/io.h> the <asm/io.h>, since linux/io.h includes
it).

Signed-off-by: Ezequiel Lara Gomez <ezegomez@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-21 14:40:02 -07:00
Ezequiel Lara Gomez 6df014cffb Enable tx timestamping on loopback and dummy
This enables developing code that uses SOF_TIMESTAMPING_TX_SOFTWARE
by using localhost addresses (without needing to send packets outside),
as well as enabling unit and functional testing of TX timestamping code
without needing hardware support or network access.

It also fulfills the expectation of software network devices supporting
software-based timestamping.

Tested on qemu using txtimestamping.c from the kernel selftests, and
ethtool -T.

Signed-off-by: Ezequiel Lara Gomez <ezegomez@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-21 14:40:01 -07:00
David S. Miller 35eeacf182 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-02-11 02:31:11 -05:00
Willem de Bruijn 217e6fa24c net: introduce device min_header_len
The stack must not pass packets to device drivers that are shorter
than the minimum link layer header length.

Previously, packet sockets would drop packets smaller than or equal
to dev->hard_header_len, but this has false positives. Zero length
payload is used over Ethernet. Other link layer protocols support
variable length headers. Support for validation of these protocols
removed the min length check for all protocols.

Introduce an explicit dev->min_header_len parameter and drop all
packets below this value. Initially, set it to non-zero only for
Ethernet and loopback. Other protocols can follow in a patch to
net-next.

Fixes: 9ed988cd59 ("packet: validate variable length ll headers")
Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-08 13:56:37 -05:00
stephen hemminger bc1f44709c net: make ndo_get_stats64 a void function
The network device operation for reading statistics is only called
in one place, and it ignores the return value. Having a structure
return value is potentially confusing because some future driver could
incorrectly assume that the return value was used.

Fix all drivers with ndo_get_stats64 to have a void function.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-08 17:51:44 -05:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Marcelo Ricardo Leitner f6c382fc55 loopback: make use of NETIF_F_GSO_SOFTWARE
NETIF_F_GSO_SOFTWARE was defined to list all GSO software types, so lets
make use of it in loopback code. Note that veth/vxlan/others already
uses it.

Within this patch series, this patch causes lo to pick up SCTP GSO feature
automatically (as it's added to NETIF_F_GSO_SOFTWARE) and thus avoiding
segmentation if possible.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03 19:37:21 -04:00
Tom Herbert 53692b1de4 sctp: Rename NETIF_F_SCTP_CSUM to NETIF_F_SCTP_CRC
The SCTP checksum is really a CRC and is very different from the
standards 1's complement checksum that serves as the checksum
for IP protocols. This offload interface is also very different.
Rename NETIF_F_SCTP_CSUM to NETIF_F_SCTP_CRC to highlight these
differences. The term CSUM should be reserved in the stack to refer
to the standard 1's complement IP checksum.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 16:49:58 -05:00
Phil Sutter e65db2b724 net: loopback: convert to using IFF_NO_QUEUE
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-18 11:55:05 -07:00
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
Tom Gundersen c835a67733 net: set name_assign_type in alloc_netdev()
Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert
all users to pass NET_NAME_UNKNOWN.

Coccinelle patch:

@@
expression sizeof_priv, name, setup, txqs, rxqs, count;
@@

(
-alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs)
+alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs)
|
-alloc_netdev_mq(sizeof_priv, name, setup, count)
+alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count)
|
-alloc_netdev(sizeof_priv, name, setup)
+alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup)
)

v9: move comments here from the wrong commit

Signed-off-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-15 16:12:48 -07:00
Eric W. Biederman 57a7744e09 net: Replace u64_stats_fetch_begin_bh to u64_stats_fetch_begin_irq
Replace the bh safe variant with the hard irq safe variant.

We need a hard irq safe variant to deal with netpoll transmitting
packets from hard irq context, and we need it in most if not all of
the places using the bh safe variant.

Except on 32bit uni-processor the code is exactly the same so don't
bother with a bh variant, just have a hard irq safe variant that
everyone can use.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 22:41:36 -04:00
Daniel Borkmann b17c706987 loopback: sctp: add NETIF_F_SCTP_CSUM to device features
Drivers are allowed to set NETIF_F_SCTP_CSUM if they have
hardware crc32c checksumming support for the SCTP protocol.
Currently, NETIF_F_SCTP_CSUM flag is available in igb,
ixgbe, i40e/i40evf drivers and for vlan devices.

If we don't have NETIF_F_SCTP_CSUM then crc32c is done
through CPU instructions, invoked from crypto layer, or
if not available as slow-path fallback in software.

Currently, loopback device propagates checksum offloading
feature flags in dev->features, but is missing SCTP checksum
offloading. Therefore, account for NETIF_F_SCTP_CSUM as
well.

Before patch:

./netperf_sctp -H 192.168.0.100 -t SCTP_STREAM_MANY
SCTP 1-TO-MANY STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.100 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

4194304 4194304   4096    10.00    4683.50

After patch:

./netperf_sctp -H 192.168.0.100 -t SCTP_STREAM_MANY
SCTP 1-TO-MANY STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.100 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

4194304 4194304   4096    10.00    15348.26

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-24 19:00:08 -05:00
WANG Cong 1c213bd24a net: introduce netdev_alloc_pcpu_stats() for drivers
There are many drivers calling alloc_percpu() to allocate pcpu stats
and then initializing ->syncp. So just introduce a helper function for them.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-14 15:49:55 -05:00
WANG Cong 25f929fbff net: allow setting mac address of loopback device
We are trying to mirror the local traffic from lo to eth0,
allowing setting mac address of lo to eth0 would make
the ether addresses in these packets correct, so that
we don't have to modify the ether header again.

Since usually no one cares about its mac address (all-zero),
it is safe to allow those who care to set its mac address.

Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 17:46:49 -05:00
Paul Gortmaker a81ab36bf5 drivers/net: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.   Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

This covers everything under drivers/net except for wireless, which
has been submitted separately.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 11:53:26 -08:00
John Stultz 827da44c61 net: Explicitly initialize u64_stats_sync structures for lockdep
In order to enable lockdep on seqcount/seqlock structures, we
must explicitly initialize any locks.

The u64_stats_sync structure, uses a seqcount, and thus we need
to introduce a u64_stats_init() function and use it to initialize
the structure.

This unfortunately adds a lot of fairly trivial initialization code
to a number of drivers. But the benefit of ensuring correctness makes
this worth while.

Because these changes are required for lockdep to be enabled, and the
changes are quite trivial, I've not yet split this patch out into 30-some
separate patches, as I figured it would be better to get the various
maintainers thoughts on how to best merge this change along with
the seqcount lockdep enablement.

Feedback would be appreciated!

Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Jesse Gross <jesse@nicira.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Roger Luethi <rl@hellgate.ch>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Simon Horman <horms@verge.net.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Wensong Zhang <wensong@linux-vs.org>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 12:40:25 +01:00
Eric W. Biederman e05e90702b net loopback: Set loopback_dev to NULL when freed
It has recently turned up that we have a number of long standing bugs
in the network stack cleanup code with use of the loopback device
after it has been freed that have not turned up because in most cases
the storage allocated to the loopback device is not reused, when those
accesses happen.

Set looback_dev to NULL to trigger oopses instead of silent data corrupt
when we hit this class of bug.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-17 19:05:13 -04:00
Eric Dumazet 794ed393b7 net: loopback: fix a dst refcounting issue
Ben Greear reported crashes in ip_rcv_finish() on a stress
test involving many macvlans.

We tracked the bug to a dst use after free. ip_rcv_finish()
was calling dst->input() and got garbage for dst->input value.

It appears the bug is in loopback driver, lacking
a skb_dst_force() before calling netif_rx().

As a result, a non refcounted dst, normally protected by a
RCU read_lock section, was escaping this section and could
be freed before the packet being processed.

  [<ffffffff813a3c4d>] loopback_xmit+0x64/0x83
  [<ffffffff81477364>] dev_hard_start_xmit+0x26c/0x35e
  [<ffffffff8147771a>] dev_queue_xmit+0x2c4/0x37c
  [<ffffffff81477456>] ? dev_hard_start_xmit+0x35e/0x35e
  [<ffffffff8148cfa6>] ? eth_header+0x28/0xb6
  [<ffffffff81480f09>] neigh_resolve_output+0x176/0x1a7
  [<ffffffff814ad835>] ip_finish_output2+0x297/0x30d
  [<ffffffff814ad6d5>] ? ip_finish_output2+0x137/0x30d
  [<ffffffff814ad90e>] ip_finish_output+0x63/0x68
  [<ffffffff814ae412>] ip_output+0x61/0x67
  [<ffffffff814ab904>] dst_output+0x17/0x1b
  [<ffffffff814adb6d>] ip_local_out+0x1e/0x23
  [<ffffffff814ae1c4>] ip_queue_xmit+0x315/0x353
  [<ffffffff814adeaf>] ? ip_send_unicast_reply+0x2cc/0x2cc
  [<ffffffff814c018f>] tcp_transmit_skb+0x7ca/0x80b
  [<ffffffff814c3571>] tcp_connect+0x53c/0x587
  [<ffffffff810c2f0c>] ? getnstimeofday+0x44/0x7d
  [<ffffffff810c2f56>] ? ktime_get_real+0x11/0x3e
  [<ffffffff814c6f9b>] tcp_v4_connect+0x3c2/0x431
  [<ffffffff814d6913>] __inet_stream_connect+0x84/0x287
  [<ffffffff814d6b38>] ? inet_stream_connect+0x22/0x49
  [<ffffffff8108d695>] ? _local_bh_enable_ip+0x84/0x9f
  [<ffffffff8108d6c8>] ? local_bh_enable+0xd/0x11
  [<ffffffff8146763c>] ? lock_sock_nested+0x6e/0x79
  [<ffffffff814d6b38>] ? inet_stream_connect+0x22/0x49
  [<ffffffff814d6b49>] inet_stream_connect+0x33/0x49
  [<ffffffff814632c6>] sys_connect+0x75/0x98

This bug was introduced in linux-2.6.35, in commit
7fee226ad2 (net: add a noref bit on skb dst)

skb_dst_force() is enforced in dev_queue_xmit() for devices having a
qdisc.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-27 01:30:35 -05:00
Eric Dumazet 0cf833aefa net: loopback: set default mtu to 64K
loopback current mtu of 16436 bytes allows no more than 3 MSS TCP
segments per frame, or 48 Kbytes. Changing mtu to 64K allows TCP
stack to build large frames and significantly reduces stack overhead.

Performance boost on bulk TCP transferts can be up to 30 %, partly
because we now have one ACK message for two 64KB segments, and a lower
probability of hitting /proc/sys/net/ipv4/tcp_reordering default limit.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-24 16:23:53 -04:00
Pavel Emelyanov 1fb9489bf1 net: Loopback ifindex is constant now
As pointed out, there are places, that access net->loopback_dev->ifindex
and after ifindex generation is made per-net this value becomes constant
equals 1. So go ahead and introduce the LOOPBACK_IFINDEX constant and use
it where appropriate.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-09 16:18:07 -07:00
Kevin Groeneveld e3906486f6 net: fix race condition in several drivers when reading stats
Fix race condition in several network drivers when reading stats on 32bit
UP architectures.  These drivers update their stats in a BH context and
therefore should use u64_stats_fetch_begin_bh/u64_stats_fetch_retry_bh
instead of u64_stats_fetch_begin/u64_stats_fetch_retry when reading the
stats.

Signed-off-by: Kevin Groeneveld <kgroeneveld@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22 12:12:32 -07:00
David Howells 9ffc93f203 Remove all #inclusions of asm/system.h
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28 18:30:03 +01:00
Michał Mirosław 34324dc2bf net: remove NETIF_F_NO_CSUM feature bit
Only distinct use is checking if NETIF_F_NOCACHE_COPY should be
enabled by default. The check heuristics is altered a bit here,
so it hits other people than before. The default shouldn't be
trusted for performance-critical cases anyway.

For all other uses NETIF_F_NO_CSUM is equivalent to NETIF_F_HW_CSUM.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-16 17:43:12 -05:00
Mahesh Bandewar eed2a12f1e net: Allow ethtool to set interface in loopback mode.
This patch enables ethtool to set the loopback mode on a given interface.
By configuring the interface in loopback mode in conjunction with a policy
route / rule, a userland application can stress the egress / ingress path
exposing the flows of the change in progress and potentially help developer(s)
understand the impact of those changes without even sending a packet out
on the network.

Following set of commands illustrates one such example -
    a) ip -4 addr add 192.168.1.1/24 dev eth1
    b) ip -4 rule add from all iif eth1 lookup 250
    c) ip -4 route add local 0/0 dev lo proto kernel scope host table 250
    d) arp -Ds 192.168.1.100 eth1
    e) arp -Ds 192.168.1.200 eth1
    f) sysctl -w net.ipv4.ip_nonlocal_bind=1
    g) sysctl -w net.ipv4.conf.all.accept_local=1
    # Assuming that the machine has 8 cores
    h) taskset 000f netserver -L 192.168.1.200
    i) taskset 00f0 netperf -t TCP_CRR -L 192.168.1.100 -H 192.168.1.200 -l 30

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08 15:59:12 -07:00
Krishna Kumar 0553c891fa ip6_pol_route panic: Do not allow VLAN on loopback
Several tests in the ipv6 routing code check IFF_LOOPBACK, and
allowing stacking such as VLAN'ing on top of loopback results in a
netdevice which reports IFF_LOOPBACK but really isn't the loopback
device.

Instead of spamming the ipv6 routing code with even more special tests,
simply disallow VLAN over loopback.

The result of this patch is:

# modprobe 8021q
# vconfig add lo 43
ERROR: trying to add VLAN #43 to IF -:lo:-  error: Operation not supported

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-17 23:27:16 -07:00
Michał Mirosław cf0bdefd46 loopback: convert to hw_features
This also enables TSOv6, TSO-ECN, and UFO as loopback clearly can handle them.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-17 14:16:35 -08:00
Eric Dumazet caf586e5f2 net: add a core netdev->rx_dropped counter
In various situations, a device provides a packet to our stack and we
drop it before it enters protocol stack :
- softnet backlog full (accounted in /proc/net/softnet_stat)
- bad vlan tag (not accounted)
- unknown/unregistered protocol (not accounted)

We can handle a per-device counter of such dropped frames at core level,
and automatically adds it to the device provided stats (rx_dropped), so
that standard tools can be used (ifconfig, ip link, cat /proc/net/dev)

This is a generalization of commit 8990f468a (net: rx_dropped
accounting), thus reverting it.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-05 14:47:55 -07:00
Eric Dumazet a7855c78a2 net: loopback driver cleanup
loopback driver uses dev->ml_priv to store its percpu stats pointer.
It uses ugly casts "(void __percpu __force *)" to shut up sparse
complains.

Define an union to better document we use ml_priv in loopback driver and
define a lstats field with appropriate types.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-26 19:04:08 -07:00
Eric Dumazet 28172739f0 net: fix 64 bit counters on 32 bit arches
There is a small possibility that a reader gets incorrect values on 32
bit arches. SNMP applications could catch incorrect counters when a
32bit high part is changed by another stats consumer/provider.

One way to solve this is to add a rtnl_link_stats64 param to all
ndo_get_stats64() methods, and also add such a parameter to
dev_get_stats().

Rule is that we are not allowed to use dev->stats64 as a temporary
storage for 64bit stats, but a caller provided area (usually on stack)

Old drivers (only providing get_stats() method) need no changes.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-07 14:58:56 -07:00
Eric Dumazet 5eaa0bd81f loopback: use u64_stats_sync infrastructure
Commit 6b10de38f0 (loopback: Implement 64bit stats on 32bit arches)
introduced 64bit stats in loopback driver, using a private seqcount and
private helpers.

David suggested to introduce a generic infrastructure, added in (net:
Introduce u64_stats_sync infrastructure)

This patch reimplements loopback 64bit stats using the u64_stats_sync
infrastructure.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-25 21:33:16 -07:00
Eric Dumazet 6b10de38f0 loopback: Implement 64bit stats on 32bit arches
Uses a seqcount_t to synchronize stat producer and consumer, for packets
and bytes counter, now u64 types.

(dropped counter being rarely used, stay a native "unsigned long" type)

No noticeable performance impact on x86, as it only adds two increments
per frame. It might be more expensive on arches where smp_wmb() is not
free.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-14 23:13:07 -07:00
Tejun Heo 47d742752d percpu: add __percpu sparse annotations to net drivers
Add __percpu sparse annotations to net drivers.

These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors.  This patch doesn't affect normal builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-16 23:05:38 -08:00
Linus Torvalds d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
Eric W. Biederman 999b6d39ab net: Simplify loopback and improve batching.
Defer calling unregister_netdevice_queue to cleanup_net.  It's simpler
and it allows the loopback device to land in the same batch as other
network devices.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-01 16:15:52 -08:00
Octavian Purdila 09ad9bc752 net: use net_eq to compare nets
Generated with the following semantic patch

@@
struct net *n1;
struct net *n2;
@@
- n1 == n2
+ net_eq(n1, n2)

@@
struct net *n1;
struct net *n2;
@@
- n1 != n2
+ !net_eq(n1, n2)

applied over {include,net,drivers/net}.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-25 15:14:13 -08:00
Christoph Lameter ca0c9584b1 this_cpu: Straight transformations
Use this_cpu_ptr and __this_cpu_ptr in locations where straight
transformations are possible because per_cpu_ptr is used with
either smp_processor_id() or raw_smp_processor_id().

cc: David Howells <dhowells@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
cc: Ingo Molnar <mingo@elte.hu>
cc: Rusty Russell <rusty@rustcorp.com.au>
cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-10-03 19:48:22 +09:00
Stephen Hemminger 61357325f3 netdev: convert bulk of drivers to netdev_tx_t
In a couple of cases collapse some extra code like:
   int retval = NETDEV_TX_OK;
   ...
   return retval;
into
   return NETDEV_TX_OK;

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-01 01:14:07 -07:00
Patrick McHardy 6ed106549d net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions
This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-05 19:16:04 -07:00
Eric Dumazet 93f154b594 net: release dst entry in dev_hard_start_xmit()
One point of contention in high network loads is the dst_release() performed
when a transmited skb is freed. This is because NIC tx completion calls
dev_kree_skb() long after original call to dev_queue_xmit(skb).

CPU cache is cold and the atomic op in dst_release() stalls. On SMP, this is
quite visible if one CPU is 100% handling softirqs for a network device,
since dst_clone() is done by other cpus, involving cache line ping pongs.

It seems right place to release dst is in dev_hard_start_xmit(), for most
devices but ones that are virtual, and some exceptions.

David Miller suggested to define a new device flag, set in alloc_netdev_mq()
(so that most devices set it at init time), and carefuly unset in devices
which dont want a NULL skb->dst in their ndo_start_xmit().

List of devices that must clear this flag is :

- loopback device, because it calls netif_rx() and quoting Patrick :
    "ip_route_input() doesn't accept loopback addresses, so loopback packets
     already need to have a dst_entry attached."
- appletalk/ipddp.c : needs skb->dst in its xmit function

- And all devices that call again dev_queue_xmit() from their xmit function
(as some classifiers need skb->dst) : bonding, vlan, macvlan, eql, ifb, hdlc_fr

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-18 22:19:19 -07:00