On 4/24/17 10:39 AM, Eric Dumazet wrote:
>
> Very nice changelog !
Thanks. Given my aggressive brain cell recycling program, I needed to
write down the analysis.
>> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
>> index 80ce478c4851..93f81d9cd85f 100644
>> --- a/net/ipv6/addrconf.c
>> +++ b/net/ipv6/addrconf.c
>> @@ -3271,14 +3271,25 @@ static void addrconf_gre_config(struct net_device
>> *dev)
>> static int fixup_permanent_addr(struct inet6_dev *idev,
>> struct inet6_ifaddr *ifp)
>> {
>> - if (!ifp->rt) {
>> - struct rt6_info *rt;
>> + /* rt6i_ref == 0 means the host route was removed from the
>> + * FIB, for example, if 'lo' device is taken down. In that
>> + * case regenerate the host route.
>> + */
>> + if (!ifp->rt || !atomic_read(&ifp->rt->rt6i_ref)) {
>> + struct rt6_info *rt, *prev;
>>
>> rt = addrconf_dst_alloc(idev, &ifp->addr, false);
>> if (unlikely(IS_ERR(rt)))
>> return PTR_ERR(rt);
>>
>> + prev = ifp->rt;
>
> I would feel more comfortable if this was moved after the spin_lock() ?
That's what I had in v2; it reads better to me even if it is not
technically required (all changes to ifp->rt happen under rtnl).
Martin you agree?
I'll send a v3 tomorrow -- allow more time for other comments.
