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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: dst_release() cleanup
Date: Tue, 08 Dec 2009 20:35:03 -0800 (PST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 07 Dec 2009 20:13:14 +0100

> Ilpo J$(D+#(Brvinen a $(D+1(Bcrit :
> 
>> That's their problem then to fix all relevant places. ...That won't even 
>> compile because of constructs like this:
>> 
>> 	if (WARN_ON(x))
>> 
>> ...To my knowing this perfectly legal way of doing this.
>> 
> 
> Sure, but let be conservative :)

It certainly jumped out at me.

Using side effects in a debugging macro, that's always asking for
trouble.  Every time I see this thing I'm going to do a double
take on it.

We can pull the return value into an 'int' with a descriptive name
such as "orig_dst_refcnt", and also use WARN() to make a descriptive
error message for kerneloops.org to log if it triggers.

Ok Eric?