From mboxrd@z Thu Jan  1 00:00:00 1970
From: Veaceslav Falico <vfalico@redhat.com>
Subject: Re: [PATCH v3 net-next 2/3] bonding: fix __get_first_agg RCU usage
Date: Fri, 10 Jan 2014 11:53:34 +0100
Message-ID: <20140110105334.GA4132@redhat.com>
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Cc: netdev@vger.kernel.org, Jay Vosburgh <fubar@us.ibm.com>,
	Andy Gospodarek <andy@greyhouse.net>
To: Ding Tianhong <dingtianhong@huawei.com>
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On Fri, Jan 10, 2014 at 06:43:41PM +0800, Ding Tianhong wrote:
>On 2014/1/10 17:18, Veaceslav Falico wrote:
>> -	rcu_read_lock();
>>  	first_slave = bond_first_slave_rcu(bond);
>> -	rcu_read_unlock();
>>
>I am afraid the lockdep check will calling some warming:
>bond_3ad_unbind_slave -> __get_first_agg -> bond_first_slave_rcu -> netdev_lower_get_first_private_rcu -> list_first_or_null_rcu
>
>but the bond_3ad_unbind_slave is not in RCU.

Yep, right, I'm always colliding with my next patchset which removes it
completely, so it doesn't whine.

Will resend.

>
>Regards
>Ding
>>  	return first_slave ? &(SLAVE_AD_INFO(first_slave).aggregator) : NULL;
>>  }
>>
>
>