If I write a few kernel modules, and in all of them specify they should be the first (or last) netfilter hook called, in what order will they actually be called?

netfilter_ops_out.hook     = hook_func_out;
netfilter_ops_out.pf       = PF_INET;
netfilter_ops_out.hooknum  = NF_IP_LOCAL_OUT;
netfilter_ops_out.priority = NF_IP_PRI_FIRST;

ret = nf_register_hook(&netfilter_ops_out);
if (0 > ret) {
    printk("Error registering netfilter hook: %d\n", ret);
    return ret;
}    

netfilter_ops_in.hook      = hook_func_in;
netfilter_ops_in.pf        = PF_INET;
netfilter_ops_in.hooknum   = NF_IP_LOCAL_IN;
netfilter_ops_in.priority  = NF_IP_PRI_LAST;

ret = nf_register_hook(&netfilter_ops_in);
if (0 > ret) {
    printk("Error registering netfilter hook: %d\n", ret);
    return ret;
}

Experimentally, I made two modules, insmoded them in the two different orders - but they gave the same result, implying there's some suborder that's not just 'first come first serve'. (It's also not alphabetical...)

linux linux-kernel netfilter
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