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Subject: Re: [BUG] perf and kmemcheck : fatal combination
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Pekka Enberg <penberg@kernel.org>, Ingo Molnar <mingo@elte.hu>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
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Date: Tue, 26 Apr 2011 14:33:08 +0200
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On Tue, 2011-04-26 at 14:27 +0200, Eric Dumazet wrote:
> Thats far from trivial, maybe because we dont have NOTRACK api for
> percpu allocations ? 

We can't use per-cpu allocations from NMI context because of the same
problem, per-cpu uses vmalloc and vmalloc needs faults. Hence that
shouldn't be a problem.

It looks like you covered most of it though, the buffer and the
callchain stuff, aside from that it should only use some static data.

Pekka, what does kmemcheck do for .data and .bss things?