linux.git/net/core/dev.c, branch v3.17-rc2

net: Always untag vlan-tagged traffic on input.

2014-08-11T19:16:51+00:00

Currently the functionality to untag traffic on input resides
as part of the vlan module and is build only when VLAN support
is enabled in the kernel.  When VLAN is disabled, the function
vlan_untag() turns into a stub and doesn't really untag the
packets.  This seems to create an interesting interaction
between VMs supporting checksum offloading and some network drivers.

There are some drivers that do not allow the user to change
tx-vlan-offload feature of the driver.  These drivers also seem
to assume that any VLAN-tagged traffic they transmit will
have the vlan information in the vlan_tci and not in the vlan
header already in the skb.  When transmitting skbs that already
have tagged data with partial checksum set, the checksum doesn't
appear to be updated correctly by the card thus resulting in a
failure to establish TCP connections.

The following is a packet trace taken on the receiver where a
sender is a VM with a VLAN configued.  The host VM is running on
doest not have VLAN support and the outging interface on the
host is tg3:
10:12:43.503055 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27243,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x48d9), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294837885 ecr 0,nop,wscale 7], length 0
10:12:44.505556 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27244,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x44ee), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294838888 ecr 0,nop,wscale 7], length 0

This connection finally times out.

I've only access to the TG3 hardware in this configuration thus have
only tested this with TG3 driver.  There are a lot of other drivers
that do not permit user changes to vlan acceleration features, and
I don't know if they all suffere from a similar issue.

The patch attempt to fix this another way.  It moves the vlan header
stipping code out of the vlan module and always builds it into the
kernel network core.  This way, even if vlan is not supported on
a virtualizatoin host, the virtual machines running on top of such
host will still work with VLANs enabled.

CC: Patrick McHardy 
CC: Nithin Nayak Sujir 
CC: Michael Chan 
CC: Jiri Pirko 
Signed-off-by: Vladislav Yasevich 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

net-timestamp: SCHED timestamp on entering packet scheduler

2014-08-05T23:35:54+00:00

Kernel transmit latency is often incurred in the packet scheduler.
Introduce a new timestamp on transmission just before entering the
scheduler. When data travels through multiple devices (bonding,
tunneling, ...) each device will export an individual timestamp.

Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller

net: Remove unlikely() for WARN_ON() conditions

2014-07-31T00:41:47+00:00

No need for the unlikely(), WARN_ON() and BUG_ON() internally use
unlikely() on the condition.

Signed-off-by: Thomas Graf 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2014-07-22T07:44:59+00:00

Conflicts:
	drivers/infiniband/hw/cxgb4/device.c

The cxgb4 conflict was simply overlapping changes.

Signed-off-by: David S. Miller

net: print a notification on device rename

2014-07-21T03:44:25+00:00

Currently it's done silently (from the kernel part), and thus it might be
hard to track the renames from logs.

Add a simple netdev_info() to notify the rename, but only in case the
previous name was valid.

CC: "David S. Miller" 
CC: Eric Dumazet 
CC: Vlad Yasevich 
CC: stephen hemminger 
CC: Jerry Chu 
CC: Ben Hutchings 
CC: David Laight 
Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

net: print net_device reg_state in netdev_* unless it's registered

2014-07-21T03:38:43+00:00

This way we'll always know in what status the device is, unless it's
running normally (i.e. NETDEV_REGISTERED).

Also, emit a warning once in case of a bad reg_state.

CC: "David S. Miller" 
CC: Jason Baron 
CC: Eric Dumazet 
CC: Vlad Yasevich 
CC: stephen hemminger 
CC: Jerry Chu 
CC: Ben Hutchings 
CC: Joe Perches 
Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

net: remove open-coded skb_cow_head.

2014-07-17T05:42:32+00:00

Signed-off-by: Francois Romieu 
Signed-off-by: David S. Miller

net-gre-gro: Fix a bug that breaks the forwarding path

2014-07-16T21:45:26+00:00

Fixed a bug that was introduced by my GRE-GRO patch
(bf5a755f5e9186406bbf50f4087100af5bd68e40 net-gre-gro: Add GRE
support to the GRO stack) that breaks the forwarding path
because various GSO related fields were not set. The bug will
cause on the egress path either the GSO code to fail, or a
GRE-TSO capable (NETIF_F_GSO_GRE) NICs to choke. The following
fix has been tested for both cases.

Signed-off-by: H.K. Jerry Chu 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2014-07-16T21:09:34+00:00

Signed-off-by: David S. Miller

net: set name_assign_type in alloc_netdev()

2014-07-15T23:12:48+00:00

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 
Reviewed-by: David Herrmann 
Signed-off-by: David S. Miller