Re: ipt_LOG and friends. Question

[Patrick McHardy <kaber@trash.net>]

Joakim Axelsson wrote:
> The default 29-32 chars as a prefix is far too little for me. Needs to
> change to 128. But again i see some code allocating this on the stack. It
> this a problem?

We can't change it due to binary compatibility. In your local tree you
can simply increase both sizes (not on the stack of course).

> The code says that a maximum of 830 chars can be used (ICMP-pcaket with
> one recursion level).

Are you sure? That sounds a bit high.

> 128 char prefix and some more on IN, OUT, PHYSIN/OUT
> and MAC fields will give an overall figure of around 1024 chars a good
> buffer length. Anything above that can probably be cut. It won't happen
> alot.
> 
> Another idea of not allocating on the stack nor using GFP_ATOMIC is to have
> a global buffer per CPU. Is this a good idea with the hot adding and
> removing of CPUs? Are linux kernel guarantied to continue on the same CPU if
> an interupt occurs and so on? 

That seems overkill, one global buffer protected by a lock will do fine.