Subject: Re: [PATCH] ipv6: Fix problem with expired dst cache

From: Gao feng <[email-masked]>
Date: Fri, 24 Feb 2012 15:10:27 +0800

于 2012年02月24日 14:47, David Miller 写道:
> From: Gao feng <[email-masked]>
> Date: Fri, 24 Feb 2012 14:20:04 +0800
> 
>> diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
>> index b26bb81..3da4d58c 100644
>> --- a/include/net/ip6_fib.h
>> +++ b/include/net/ip6_fib.h
>> @@ -106,6 +106,7 @@ struct rt6_info {
>>  	u32				rt6i_metric;
>>  	u32				rt6i_peer_genid;
>>  
>> +	struct rt6_info			*rt6i_copy;
>>  	struct inet6_dev		*rt6i_idev;
>>  	struct inet_peer		*rt6i_peer;
> 
> This bloats up every route and cached entry in the machine, find
> another way.

Another way is set dst cache's RTF_EXPIRES flag and expires in ip6_rt_copy
and when receive RA packet,update all the related dst cache's expires.
I don't think this is a good idea.

> 
>> +	if ((rt->rt6i_flags & RTF_EXPIRES) &&
>> +		time_after(jiffies, rt->dst.expires))
> 
> Poorly formatted, correct way is:
> 
> 	if ((rt->rt6i_flags & RTF_EXPIRES) &&
> 	    time_after(jiffies, rt->dst.expires))
> 
>> +	if (rt->rt6i_copy && (rt->rt6i_copy->rt6i_flags & RTF_EXPIRES) &&
>> +		time_after(jiffies, rt->rt6i_copy->dst.expires))
> 
> Same problem.
>