From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@o2.pl>
Subject: Re: BUG: soft lockup detected on CPU#0! (2.6.18.2 plus hacks)
Date: Mon, 8 Jan 2007 07:53:46 +0100
Message-ID: <20070108065346.GA1665@ff.dom.local>
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Cc: David Miller <davem@davemloft.net>, herbert@gondor.apana.org.au,
	dlstevens@us.ibm.com, netdev@vger.kernel.org
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To: Ben Greear <greearb@candelatech.com>
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On Fri, Jan 05, 2007 at 12:33:43PM -0800, Ben Greear wrote:
...
> So, I do believe this was the problem we were hitting, and it seems fixed.

Congratulations!

But I can see one strange thing in vlan.c:

/* Must be invoked with RCU read lock (no preempt) */
static struct vlan_group *__vlan_find_group(int real_dev_ifindex)
...
 * Must be invoked with RCU read lock (no preempt)
 */
struct net_device *__find_vlan_dev(struct net_device *real_dev,
...

But later in this file no sign of disabling preemption
for these calls and for hlist_add_head_rcu and hlist_del_rcu.

I can't imagine how this works?

Jarek P.