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Andrey Vagin 88997e4208 net/8021q: create device with all possible features in wanted_features
wanted_features is a set of features which have to be enabled if a
hardware allows that.

Currently when a vlan device is created, its wanted_features is set to
current features of its base device.

The problem is that the base device can get new features and they are
not propagated to vlan-s of this device.

If we look at bonding devices, they doesn't have this problem and this
patch suggests to fix this issue by the same way how it works for bonding
devices.

We meet this problem, when we try to create a vlan device over a bonding
device. When a system are booting, real devices require time to be
initialized, so bonding devices created without slaves, then vlan
devices are created and only then ethernet devices are added to the
bonding device. As a result we have vlan devices with disabled
scatter-gather.

* create a bonding device
  $ ip link add bond0 type bond
  $ ethtool -k bond0 | grep scatter
  scatter-gather: off
	tx-scatter-gather: off [requested on]
	tx-scatter-gather-fraglist: off [requested on]

* create a vlan device
  $ ip link add link bond0 name bond0.10 type vlan id 10
  $ ethtool -k bond0.10 | grep scatter
  scatter-gather: off
	tx-scatter-gather: off
	tx-scatter-gather-fraglist: off

* Add a slave device to bond0
  $ ip link set dev eth0 master bond0

And now we can see that the bond0 device has got the scatter-gather
feature, but the bond0.10 hasn't got it.
[root@laptop linux-task-diag]# ethtool -k bond0 | grep scatter
scatter-gather: on
	tx-scatter-gather: on
	tx-scatter-gather-fraglist: on
[root@laptop linux-task-diag]# ethtool -k bond0.10 | grep scatter
scatter-gather: off
	tx-scatter-gather: off
	tx-scatter-gather-fraglist: off

With this patch the vlan device will get all new features from the
bonding device.

Here is a call trace how features which are set in this patch reach
dev->wanted_features.

register_netdevice
   vlan_dev_init
	...
	dev->hw_features = NETIF_F_HW_CSUM | NETIF_F_SG |
		       NETIF_F_FRAGLIST | NETIF_F_GSO_SOFTWARE |
		       NETIF_F_HIGHDMA | NETIF_F_SCTP_CRC |
		       NETIF_F_ALL_FCOE;

	dev->features |= dev->hw_features;
	...
    dev->wanted_features = dev->features & dev->hw_features;
    __netdev_update_features(dev);
        vlan_dev_fix_features
	   ...

Cc: Alexey Kuznetsov <kuznet@virtuozzo.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-21 15:26:26 -07:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-03-21 14:28:08 -07:00
arch Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-03-15 09:26:04 -07:00
block blk: improve order of bio handling in generic_make_request() 2017-03-08 10:55:17 -07:00
certs certs: Add a secondary system keyring that can be added to dynamically 2016-04-11 22:48:09 +01:00
crypto net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
drivers Cleanup some warning from timestamping code. 2017-03-21 14:40:02 -07:00
firmware WHENCE: use https://linuxtv.org for LinuxTV URLs 2015-12-04 10:35:11 -02:00
fs gfs2: Avoid alignment hole in struct lm_lockname 2017-03-15 10:06:07 -04:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-03-21 14:28:08 -07:00
init Change get_random_{int,log} to use the CRNG used by /dev/urandom and 2017-03-11 09:08:47 -08:00
ipc Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
kernel bpf: inline htab_map_lookup_elem() 2017-03-16 20:44:11 -07:00
lib mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
mm Merge branch 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2017-03-14 14:48:50 -07:00
net net/8021q: create device with all possible features in wanted_features 2017-03-21 15:26:26 -07:00
samples samples/bpf: add map_lookup microbenchmark 2017-03-16 20:44:12 -07:00
scripts Merge branch 'akpm' (patches from Andrew) 2017-03-10 08:34:42 -08:00
security Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
sound scripts/spelling.txt: add "disble(d)" pattern and fix typo instances 2017-03-09 17:01:09 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-03-15 11:59:10 -07:00
usr kbuild: initramfs cleanup, set target from Kconfig 2017-01-05 09:40:16 -08:00
virt KVM: arm/arm64: VGIC: Fix command handling while ITS being disabled 2017-03-07 15:44:08 +00:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-08-02 16:48:52 -04:00
.mailmap mailmap: add codeaurora.org names for nameless email commits 2017-01-10 18:31:55 -08:00
COPYING
CREDITS MAINTAINERS: Remove old e-mail address 2017-02-13 12:24:56 -05:00
Kbuild scripts/gdb: provide linux constants 2016-05-23 17:04:14 -07:00
Kconfig
MAINTAINERS MAINTAINERS: Update X-Gene SoC ethernet maintainer 2017-03-15 21:52:52 -07:00
Makefile Linux 4.11-rc2 2017-03-12 14:47:08 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.