tipc_mon_create() is never called in atomic context.

The call chain ending up at dn_route_init() is:
[1] tipc_mon_create() <- tipc_enable_bearer() <- tipc_nl_bearer_enable()
tipc_nl_bearer_enable() calls rtnl_lock(), which indicates this function
is not called in atomic context.

Despite never getting called from atomic context,
tipc_mon_create() calls kzalloc() with GFP_ATOMIC,
which waits busily for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
to avoid busy waiting and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1...@gmail.com>
 net/tipc/monitor.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/tipc/monitor.c b/net/tipc/monitor.c
index 9e109bb..9714d80 100644
--- a/net/tipc/monitor.c
+++ b/net/tipc/monitor.c
@@ -604,9 +604,9 @@ int tipc_mon_create(struct net *net, int bearer_id)
        if (tn->monitors[bearer_id])
                return 0;
-       mon = kzalloc(sizeof(*mon), GFP_ATOMIC);
-       self = kzalloc(sizeof(*self), GFP_ATOMIC);
-       dom = kzalloc(sizeof(*dom), GFP_ATOMIC);
+       mon = kzalloc(sizeof(*mon), GFP_KERNEL);
+       self = kzalloc(sizeof(*self), GFP_KERNEL);
+       dom = kzalloc(sizeof(*dom), GFP_KERNEL);
        if (!mon || !self || !dom) {

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