From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@davemloft.net>
Subject: Re: [PATCH] fix iptables on systems with discontiguous processor ids
Date: Mon, 10 Oct 2005 15:06:23 -0700 (PDT)
Message-ID: <20051010.150623.94217913.davem@davemloft.net>
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From: Patrick McHardy <kaber@trash.net>
Date: Mon, 10 Oct 2005 23:52:11 +0200

> I don't know which other architectures are affected by this, but for
> the case Dave mentioned some function
> 
> static inline int cpu_physical_id(void)
> {
> 	return smp_processor_id() >> 1;
> }
> 
> should also solve the problem. Even if not as easily implementable
> as this. it looks like a logical complement to num_possible_cpus().

Stop papering around this issue, please. :-)

The cpu ID space is discontiguous, period.

If you need to allocate per-cpu data there are very straightforward
ways to do this.  Many other subsystems do this in an error free
manner and I think netfilter iptables can do it too. :)