From a898def29e4119bc01ebe7ca97423181f4c0ea2d Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:04:49 -0800 Subject: net: Add checking to rcu_dereference() primitives Update rcu_dereference() primitives to use new lockdep-based checking. The rcu_dereference() in __in6_dev_get() may be protected either by rcu_read_lock() or RTNL, per Eric Dumazet. The rcu_dereference() in __sk_free() is protected by the fact that it is never reached if an update could change it. Check for this by using rcu_dereference_check() to verify that the struct sock's ->sk_wmem_alloc counter is zero. Acked-by: Eric Dumazet Acked-by: David S. Miller Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-5-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- net/decnet/dn_route.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'net/decnet') diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c index a03284061a31..a7bf03ca0a36 100644 --- a/net/decnet/dn_route.c +++ b/net/decnet/dn_route.c @@ -1155,8 +1155,8 @@ static int __dn_route_output_key(struct dst_entry **pprt, const struct flowi *fl if (!(flags & MSG_TRYHARD)) { rcu_read_lock_bh(); - for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt; - rt = rcu_dereference(rt->u.dst.dn_next)) { + for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt; + rt = rcu_dereference_bh(rt->u.dst.dn_next)) { if ((flp->fld_dst == rt->fl.fld_dst) && (flp->fld_src == rt->fl.fld_src) && (flp->mark == rt->fl.mark) && @@ -1618,9 +1618,9 @@ int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb) if (h > s_h) s_idx = 0; rcu_read_lock_bh(); - for(rt = rcu_dereference(dn_rt_hash_table[h].chain), idx = 0; + for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0; rt; - rt = rcu_dereference(rt->u.dst.dn_next), idx++) { + rt = rcu_dereference_bh(rt->u.dst.dn_next), idx++) { if (idx < s_idx) continue; skb_dst_set(skb, dst_clone(&rt->u.dst)); @@ -1654,12 +1654,12 @@ static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq) for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) { rcu_read_lock_bh(); - rt = dn_rt_hash_table[s->bucket].chain; + rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain); if (rt) break; rcu_read_unlock_bh(); } - return rcu_dereference(rt); + return rt; } static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt) @@ -1674,7 +1674,7 @@ static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_rou rcu_read_lock_bh(); rt = dn_rt_hash_table[s->bucket].chain; } - return rcu_dereference(rt); + return rcu_dereference_bh(rt); } static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos) -- cgit v1.2.3-59-g8ed1b