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authorDavid S. Miller <davem@davemloft.net>2019-02-15 12:38:38 -0800
committerDavid S. Miller <davem@davemloft.net>2019-02-15 12:38:38 -0800
commit3313da8188cc346a205783c22c37e821b4b7016d (patch)
tree5697cd985220def9bc2e35dfbb832dad04c2d051 /Documentation/networking
parent50f444aa50a4f3fab35a04f56d6bb83dc1e8c875 (diff)
parent24f0a48743a256bdec1bcb80708bc309da4aa261 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The netfilter conflicts were rather simple overlapping changes. However, the cls_tcindex.c stuff was a bit more complex. On the 'net' side, Cong is fixing several races and memory leaks. Whilst on the 'net-next' side we have Vlad adding the rtnl-ness support. What I've decided to do, in order to resolve this, is revert the conversion over to using a workqueue that Cong did, bringing us back to pure RCU. I did it this way because I believe that either Cong's races don't apply with have Vlad did things, or Cong will have to implement the race fix slightly differently. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation/networking')
-rw-r--r--Documentation/networking/operstates.txt14
1 files changed, 8 insertions, 6 deletions
diff --git a/Documentation/networking/operstates.txt b/Documentation/networking/operstates.txt
index 355c6d8ef8ad..b203d1334822 100644
--- a/Documentation/networking/operstates.txt
+++ b/Documentation/networking/operstates.txt
@@ -22,8 +22,9 @@ and changeable from userspace under certain rules.
2. Querying from userspace
Both admin and operational state can be queried via the netlink
-operation RTM_GETLINK. It is also possible to subscribe to RTMGRP_LINK
-to be notified of updates. This is important for setting from userspace.
+operation RTM_GETLINK. It is also possible to subscribe to RTNLGRP_LINK
+to be notified of updates while the interface is admin up. This is
+important for setting from userspace.
These values contain interface state:
@@ -101,8 +102,9 @@ because some driver controlled protocol establishment has to
complete. Corresponding functions are netif_dormant_on() to set the
flag, netif_dormant_off() to clear it and netif_dormant() to query.
-On device allocation, networking core sets the flags equivalent to
-netif_carrier_ok() and !netif_dormant().
+On device allocation, both flags __LINK_STATE_NOCARRIER and
+__LINK_STATE_DORMANT are cleared, so the effective state is equivalent
+to netif_carrier_ok() and !netif_dormant().
Whenever the driver CHANGES one of these flags, a workqueue event is
@@ -133,11 +135,11 @@ netif_carrier_ok() && !netif_dormant() is set by the
driver. Afterwards, the userspace application can set IFLA_OPERSTATE
to IF_OPER_DORMANT or IF_OPER_UP as long as the driver does not set
netif_carrier_off() or netif_dormant_on(). Changes made by userspace
-are multicasted on the netlink group RTMGRP_LINK.
+are multicasted on the netlink group RTNLGRP_LINK.
So basically a 802.1X supplicant interacts with the kernel like this:
--subscribe to RTMGRP_LINK
+-subscribe to RTNLGRP_LINK
-set IFLA_LINKMODE to 1 via RTM_SETLINK
-query RTM_GETLINK once to get initial state
-if initial flags are not (IFF_LOWER_UP && !IFF_DORMANT), wait until