net: openvswitch: silence suspicious RCU usage warning (5845589e) · Commits · 戴 / test

ovs_flow_tbl_destroy always is called from RCU callback or error path. It is no need to check if rcu_read_lock or lockdep_ovsl_is_held was held. ovs_dp_cmd_fill_info always is called with ovs_mutex, So use the rcu_dereference_ovsl instead of rcu_dereference in ovs_flow_tbl_masks_cache_size. Fixes: ("net: openvswitch: make masks cache size configurable") Cc: Eelco Chaudron <echaudro@redhat.com> Reported-by:

<syzbot+c0eb9e7cdde04e4eb4be@syzkaller.appspotmail.com> Reported-by:

<syzbot+f612c02823acb02ff9bc@syzkaller.appspotmail.com> Signed-off-by:

Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by:

Paolo Abeni <pabeni@redhat.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/openvswitch/flow_table.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -518,8 +518,8 @@ void ovs_flow_tbl_destroy(struct flow_table *table)
		{
		struct table_instance *ti = rcu_dereference_raw(table->ti);
		struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti);
		struct mask_cache *mc = rcu_dereference(table->mask_cache);
		struct mask_array *ma = rcu_dereference_ovsl(table->mask_array);
		struct mask_cache *mc = rcu_dereference_raw(table->mask_cache);
		struct mask_array *ma = rcu_dereference_raw(table->mask_array);

		call_rcu(&mc->rcu, mask_cache_rcu_cb);
		call_rcu(&ma->rcu, mask_array_rcu_cb);
		@@ -937,7 +937,7 @@ int ovs_flow_tbl_num_masks(const struct flow_table *table)

		u32 ovs_flow_tbl_masks_cache_size(const struct flow_table *table)
		{
		struct mask_cache *mc = rcu_dereference(table->mask_cache);
		struct mask_cache *mc = rcu_dereference_ovsl(table->mask_cache);

		return READ_ONCE(mc->cache_size);
		}

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