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Subject: Re: [BUG] perf and kmemcheck : fatal combination
From: Pekka Enberg <penberg@kernel.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Dumazet <eric.dumazet@gmail.com>, Ingo Molnar <mingo@elte.hu>,
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Date: Tue, 26 Apr 2011 22:13:12 +0300
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On Tue, 2011-04-26 at 14:33 +0200, Peter Zijlstra wrote:
> 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?

No, kmemcheck is only active for memory allocated with slab and the page
allocator .