linux-stable/net
Jarod Wilson fd867d51f8 net/core: generic support for disabling netdev features down stack
There are some netdev features, which when disabled on an upper device,
such as a bonding master or a bridge, must be disabled and cannot be
re-enabled on underlying devices.

This is a rework of an earlier more heavy-handed appraoch, which simply
disables and prevents re-enabling of netdev features listed in a new
define in include/net/netdev_features.h, NETIF_F_UPPER_DISABLES. Any upper
device that disables a flag in that feature mask, the disabling will
propagate down the stack, and any lower device that has any upper device
with one of those flags disabled should not be able to enable said flag.

Initially, only LRO is included for proof of concept, and because this
code effectively does the same thing as dev_disable_lro(), though it will
also activate from the ethtool path, which was one of the goals here.

[root@dell-per730-01 ~]# ethtool -k bond0 |grep large
large-receive-offload: on
[root@dell-per730-01 ~]# ethtool -k p5p1 |grep large
large-receive-offload: on
[root@dell-per730-01 ~]# ethtool -K bond0 lro off
[root@dell-per730-01 ~]# ethtool -k bond0 |grep large
large-receive-offload: off
[root@dell-per730-01 ~]# ethtool -k p5p1 |grep large
large-receive-offload: off

dmesg dump:

[ 1033.277986] bond0: Disabling feature 0x0000000000008000 on lower dev p5p2.
[ 1034.067949] bnx2x 0000:06:00.1 p5p2: using MSI-X  IRQs: sp 74  fp[0] 76 ... fp[7] 83
[ 1034.753612] bond0: Disabling feature 0x0000000000008000 on lower dev p5p1.
[ 1035.591019] bnx2x 0000:06:00.0 p5p1: using MSI-X  IRQs: sp 62  fp[0] 64 ... fp[7] 71

This has been successfully tested with bnx2x, qlcnic and netxen network
cards as slaves in a bond interface. Turning LRO on or off on the master
also turns it on or off on each of the slaves, new slaves are added with
LRO in the same state as the master, and LRO can't be toggled on the
slaves.

Also, this should largely remove the need for dev_disable_lro(), and most,
if not all, of its call sites can be replaced by simply making sure
NETIF_F_LRO isn't included in the relevant device's feature flags.

Note that this patch is driven by bug reports from users saying it was
confusing that bonds and slaves had different settings for the same
features, and while it won't be 100% in sync if a lower device doesn't
support a feature like LRO, I think this is a good step in the right
direction.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Nikolay Aleksandrov <razor@blackwall.org>
CC: Michal Kubecek <mkubecek@suse.cz>
CC: Alexander Duyck <alexander.duyck@gmail.com>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 23:41:31 -05:00
..
6lowpan 6lowpan: put mcast compression in an own function 2015-10-21 00:49:25 +02:00
9p
802
8021q
appletalk
atm
ax25
batman-adv
bluetooth bluetooth: 6lowpan: fix NOHZ: local_softirq_pending 2015-10-27 09:53:36 +01:00
bridge bridge: vlan: Use rcu_dereference instead of rtnl_dereference 2015-11-02 16:27:39 -05:00
caif
can can: avoid using timeval for uapi 2015-10-13 17:42:34 +02:00
ceph rbd: use writefull op for object size writes 2015-10-16 16:49:01 +02:00
core net/core: generic support for disabling netdev features down stack 2015-11-02 23:41:31 -05:00
dcb net/dcb: make dcbnl.c explicitly non-modular 2015-10-09 07:52:27 -07:00
dccp tcp/dccp: fix ireq->pktopts race 2015-11-02 15:38:26 -05:00
decnet Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2015-10-17 14:28:03 +02:00
dns_resolver
dsa net: dsa: use switchdev obj for VLAN add/del ops 2015-11-01 15:56:11 -05:00
ethernet
hsr
ieee802154 net: fix percpu memory leaks 2015-11-02 22:47:14 -05:00
ipv4 net: fix percpu memory leaks 2015-11-02 22:47:14 -05:00
ipv6 net: fix percpu memory leaks 2015-11-02 22:47:14 -05:00
ipx
irda irda: precedence bug in irlmp_seq_hb_idx() 2015-10-21 07:48:26 -07:00
iucv
key af_key: fix two typos 2015-10-23 03:05:19 -07:00
l2tp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-02 07:21:25 -07:00
l3mdev net: Add netif_is_l3_slave 2015-10-07 04:27:43 -07:00
lapb
llc
mac80211 Here's another set of patches for the current cycle: 2015-10-22 07:28:41 -07:00
mac802154 mac802154: llsec: use kzfree 2015-10-21 00:49:24 +02:00
mpls mpls: reduce memory usage of routes 2015-10-27 19:52:59 -07:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-24 06:54:12 -07:00
netlabel
netlink Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-24 06:54:12 -07:00
netrom
nfc NFC: nci: non-static functions can not be inline 2015-10-28 06:44:45 +01:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-01 00:15:30 -04:00
packet ipv4: Pass struct net into ip_defrag and ip_check_defrag 2015-10-12 19:44:16 -07:00
phonet
rds RDS: convert bind hash table to re-sizable hashtable 2015-11-02 15:36:23 -05:00
rfkill
rose
rxrpc
sched Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-20 06:08:27 -07:00
sctp net: sctp: avoid incorrect time_t use 2015-10-05 03:16:48 -07:00
sunrpc Changes for 4.3-rc5 2015-10-15 13:44:35 -07:00
switchdev switchdev: fix: pass correct obj size when deferring obj add 2015-10-30 20:23:37 +09:00
tipc tipc: link_is_bc_sndlink() can be static 2015-10-25 06:31:52 -07:00
unix af_unix: do not report POLLOUT on listeners 2015-10-25 06:37:45 -07:00
vmw_vsock VSOCK: define VSOCK_SS_LISTEN once only 2015-11-01 12:14:47 -05:00
wimax
wireless cfg80211: reg: fix reg_ignore_cell_hint return type 2015-10-16 09:15:45 +02:00
x25
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2015-10-30 20:51:56 +09:00
compat.c
Kconfig net: Introduce L3 Master device abstraction 2015-09-29 20:40:32 -07:00
Makefile net: Introduce L3 Master device abstraction 2015-09-29 20:40:32 -07:00
socket.c
sysctl_net.c net: sysctl: fix a kmemleak warning 2015-10-23 06:22:08 -07:00