[NETLINK]: Switch cb_lock spinlock to mutex and allow to override it

Switch cb_lock to mutex and allow netlink kernel users to override it
with a subsystem specific mutex for consistent locking in dump callbacks.
All netlink_dump_start users have been audited not to rely on any
side-effects of the previously used spinlock.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 5bf718a3e49b..953dd458c239 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -827,7 +827,8 @@ static void nl_fib_input(struct sock *sk, int len)
 
 static void nl_fib_lookup_init(void)
 {
-      netlink_kernel_create(NETLINK_FIB_LOOKUP, 0, nl_fib_input, THIS_MODULE);
+      netlink_kernel_create(NETLINK_FIB_LOOKUP, 0, nl_fib_input, NULL,
+                            THIS_MODULE);
 }
 
 static void fib_disable_ip(struct net_device *dev, int force)