linux-toradex.git/include/linux/genetlink.h, branch v4.6-rc6

net/netlink: lockdep_genl_is_held can be boolean

2015-10-09T14:48:59+00:00

This patch makes lockdep_genl_is_held return bool to improve
readability due to this particular function only using either
one or zero as its return value.

No functional change.

Signed-off-by: Yaowei Bai 
Signed-off-by: David S. Miller

genetlink: synchronize socket closing and family removal

2015-01-16T22:04:25+00:00

In addition to the problem Jeff Layton reported, I looked at the code
and reproduced the same warning by subscribing and removing the genl
family with a socket still open. This is a fairly tricky race which
originates in the fact that generic netlink allows the family to go
away while sockets are still open - unlike regular netlink which has
a module refcount for every open socket so in general this cannot be
triggered.

Trying to resolve this issue by the obvious locking isn't possible as
it will result in deadlocks between unregistration and group unbind
notification (which incidentally lockdep doesn't find due to the home
grown locking in the netlink table.)

To really resolve this, introduce a "closing socket" reference counter
(for generic netlink only, as it's the only affected family) in the
core netlink code and use that in generic netlink to wait for all the
sockets that are being closed at the same time as a generic netlink
family is removed.

This fixes the race that when a socket is closed, it will should call
the unbind, but if the family is removed at the same time the unbind
will not find it, leading to the warning. The real problem though is
that in this case the unbind could actually find a new family that is
registered to have a multicast group with the same ID, and call its
mcast_unbind() leading to confusing.

Also remove the warning since it would still trigger, but is now no
longer a problem.

This also moves the code in af_netlink.c to before unreferencing the
module to avoid having the same problem in the normal non-genl case.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

UAPI: (Scripted) Disintegrate include/linux

2012-10-13T09:46:48+00:00

Signed-off-by: David Howells 
Acked-by: Arnd Bergmann 
Acked-by: Thomas Gleixner 
Acked-by: Michael Kerrisk 
Acked-by: Paul E. McKenney 
Acked-by: Dave Jones

genetlink: define lockdep_genl_is_held() when CONFIG_LOCKDEP

2012-07-24T07:01:30+00:00

lockdep_is_held() is defined when CONFIG_LOCKDEP, not CONFIG_PROVE_LOCKING.

Cc: "David S. Miller" 
Cc: Jesse Gross 
Signed-off-by: WANG Cong 
Signed-off-by: David S. Miller

genetlink: Build a generic netlink family module alias

2012-05-30T02:33:56+00:00

Generic netlink searches for -type- formatted aliases when requesting a module to
fulfill a protocol request (i.e. net-pf-16-proto-16-type-, where x is a type
value).  However generic netlink protocols have no well defined type numbers,
they have string names.  Modify genl_ctrl_getfamily to request an alias in the
format net-pf-16-proto-16-family- instead, where x is a generic string, and
add a macro that builds on the previously added MODULE_ALIAS_NET_PF_PROTO_NAME
macro to allow modules to specifify those generic strings.

Note, l2tp previously hacked together an net-pf-16-proto-16-type-l2tp alias
using the MODULE_ALIAS macro, with these updates we can convert that to use the
PROTO_NAME macro.

Signed-off-by: Neil Horman 
CC: Eric Dumazet 
CC: James Chapman 
CC: David Miller 
Signed-off-by: David S. Miller

genetlink: Add rcu_dereference_genl and genl_dereference.

2011-12-03T17:35:08+00:00

This adds rcu_dereference_genl and genl_dereference, which are genl
variants of the RTNL functions to enforce proper locking with lockdep
and sparse.

Signed-off-by: Jesse Gross

genetlink: Add lockdep_genl_is_held().

2011-12-03T17:35:07+00:00

Open vSwitch uses genl_mutex locking to protect datapath
data-structures like flow-table, flow-actions. Following patch adds
lockdep_genl_is_held() which is used for rcu annotation to prove
locking.

Signed-off-by: Pravin B Shelar 
Signed-off-by: Jesse Gross

netlink: Export genl_lock() API for use by modules

2010-04-03T21:56:05+00:00

This lets kernel modules which use genl netlink APIs serialize netlink
processing.

Signed-off-by: James Chapman 
Reviewed-by: Randy Dunlap 
Signed-off-by: David S. Miller

headers_check fix: linux/genetlink.h

2009-01-30T18:19:39+00:00

fix the following 'make headers_check' warning:

  usr/include/linux/genetlink.h:12: found __[us]{8,16,32,64} type without #include 

Signed-off-by: Jaswinder Singh Rajput

[GENETLINK]: Dynamic multicast groups.

2007-07-18T22:47:52+00:00

Introduce API to dynamically register and unregister multicast groups.

Signed-off-by: Johannes Berg 
Acked-by: Patrick McHardy 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller