From 8d7e5dee972f1cde2ba96c621f1541fa36e7d4f4 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Mon, 13 Jan 2020 22:39:23 +0100 Subject: [PATCH] netns: don't disable BHs when locking "nsid_lock" When peernet2id() had to lock "nsid_lock" before iterating through the nsid table, we had to disable BHs, because VXLAN can call peernet2id() from the xmit path: vxlan_xmit() -> vxlan_fdb_miss() -> vxlan_fdb_notify() -> __vxlan_fdb_notify() -> vxlan_fdb_info() -> peernet2id(). Now that peernet2id() uses RCU protection, "nsid_lock" isn't used in BH context anymore. Therefore, we can safely use plain spin_lock()/spin_unlock() and let BHs run when holding "nsid_lock". Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller --- net/core/net_namespace.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index e7a5ff4966c9..6412c1fbfcb5 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -237,10 +237,10 @@ int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp) if (refcount_read(&net->count) == 0) return NETNSA_NSID_NOT_ASSIGNED; - spin_lock_bh(&net->nsid_lock); + spin_lock(&net->nsid_lock); id = __peernet2id(net, peer); if (id >= 0) { - spin_unlock_bh(&net->nsid_lock); + spin_unlock(&net->nsid_lock); return id; } @@ -250,12 +250,12 @@ int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp) * just been idr_remove()'d from there in cleanup_net(). */ if (!maybe_get_net(peer)) { - spin_unlock_bh(&net->nsid_lock); + spin_unlock(&net->nsid_lock); return NETNSA_NSID_NOT_ASSIGNED; } id = alloc_netid(net, peer, -1); - spin_unlock_bh(&net->nsid_lock); + spin_unlock(&net->nsid_lock); put_net(peer); if (id < 0) @@ -520,20 +520,20 @@ static void unhash_nsid(struct net *net, struct net *last) for_each_net(tmp) { int id; - spin_lock_bh(&tmp->nsid_lock); + spin_lock(&tmp->nsid_lock); id = __peernet2id(tmp, net); if (id >= 0) idr_remove(&tmp->netns_ids, id); - spin_unlock_bh(&tmp->nsid_lock); + spin_unlock(&tmp->nsid_lock); if (id >= 0) rtnl_net_notifyid(tmp, RTM_DELNSID, id, 0, NULL, GFP_KERNEL); if (tmp == last) break; } - spin_lock_bh(&net->nsid_lock); + spin_lock(&net->nsid_lock); idr_destroy(&net->netns_ids); - spin_unlock_bh(&net->nsid_lock); + spin_unlock(&net->nsid_lock); } static LLIST_HEAD(cleanup_list); @@ -746,9 +746,9 @@ static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh, return PTR_ERR(peer); } - spin_lock_bh(&net->nsid_lock); + spin_lock(&net->nsid_lock); if (__peernet2id(net, peer) >= 0) { - spin_unlock_bh(&net->nsid_lock); + spin_unlock(&net->nsid_lock); err = -EEXIST; NL_SET_BAD_ATTR(extack, nla); NL_SET_ERR_MSG(extack, @@ -757,7 +757,7 @@ static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh, } err = alloc_netid(net, peer, nsid); - spin_unlock_bh(&net->nsid_lock); + spin_unlock(&net->nsid_lock); if (err >= 0) { rtnl_net_notifyid(net, RTM_NEWNSID, err, NETLINK_CB(skb).portid, nlh, GFP_KERNEL); -- 2.30.2