net: allow sleeping when modifying store_rps_map

Commit 10e4ea751 ("net: Fix race condition in store_rps_map") has moved the
manipulation of the rps_needed jump label under a spinlock. Since changing
the state of a jump label may sleep this is incorrect and causes warnings
during runtime.

Make rps_map_lock a mutex to allow sleeping under it.

Fixes: 10e4ea751 ("net: Fix race condition in store_rps_map")
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 39ec6949c1e644d0308a588ce2672b9fb6634966..b279077c30894dfeb69e2c21686d702cc809e678 100644 (file)
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -689,7 +689,7 @@ static ssize_t store_rps_map(struct netdev_rx_queue *queue,
        struct rps_map *old_map, *map;
        cpumask_var_t mask;
        int err, cpu, i;
-       static DEFINE_SPINLOCK(rps_map_lock);
+       static DEFINE_MUTEX(rps_map_mutex);
 
        if (!capable(CAP_NET_ADMIN))
                return -EPERM;
@@ -722,9 +722,9 @@ static ssize_t store_rps_map(struct netdev_rx_queue *queue,
                map = NULL;
        }
 
-       spin_lock(&rps_map_lock);
+       mutex_lock(&rps_map_mutex);
        old_map = rcu_dereference_protected(queue->rps_map,
-                                           lockdep_is_held(&rps_map_lock));
+                                           mutex_is_locked(&rps_map_mutex));
        rcu_assign_pointer(queue->rps_map, map);
 
        if (map)
@@ -732,7 +732,7 @@ static ssize_t store_rps_map(struct netdev_rx_queue *queue,
        if (old_map)
                static_key_slow_dec(&rps_needed);
 
-       spin_unlock(&rps_map_lock);
+       mutex_unlock(&rps_map_mutex);
 
        if (old_map)
                kfree_rcu(old_map, rcu);