From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steffen Klassert <steffen.klassert@secunet.com>
Subject: Re: [PATCH net] net/flow: fix fc->percpu NULL pointer dereference
Date: Fri, 9 Jun 2017 10:32:55 +0200
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Cc: David Miller <davem@davemloft.net>,
        Xin Long <lucien.xin@gmail.com>,
        network dev <netdev@vger.kernel.org>
To: Hangbin Liu <liuhangbin@gmail.com>
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On Fri, Jun 09, 2017 at 04:23:01PM +0800, Hangbin Liu wrote:
> Hi Steffen,
> 
> BTW, If we put the check in xfrm_policy_flush(), we can prevent it earlier.
> But If we put the check in flow_cache_percpu_empty(), we can prevent
> other functions set fc->percpu to NULL, although not much possible : )
> 
> So I'm not quite sure whether we should put the check in
> flow_cache_percpu_empty() or in xfrm_policy_flush().

Can't we just call xfrm_policy_fini() first and then flow_cache_fini()?