rcu_deference

["jingle2422" <jingle2422@xxxxxxx>]

Hi all:

        I encounter one problem in

"int dev_queue_xmit(struct sk_buff *skb)"function.

"q = rcu_dereference(dev->qdisc);"

 

"rcu_dereference(dev->qdisc)" will return a non aligned pointer, so it will crash my system,

so why this happend???Can you give some advice to avoid this.

 

 

 

q = rcu_dereference(dev->qdisc);
#ifdef CONFIG_NET_CLS_ACT
    skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS);
#endif
    if (q->enqueue) {
        /* Grab device queue */
        spin_lock(&dev->queue_lock);
        q = dev->qdisc;
        if (q->enqueue) {
            rc = q->enqueue(skb, q);
            qdisc_run(dev);
            spin_unlock(&dev->queue_lock);

            rc = rc == NET_XMIT_BYPASS ? NET_XMIT_SUCCESS : rc;
            goto out;
        }
        spin_unlock(&dev->queue_lock);
    }