Subject: Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP)
From: Peter Zijlstra <peterz@infradead.org>
To: Avi Kivity <avi@redhat.com>
Cc: ananth@in.ibm.com, Jim Keniston <jkenisto@us.ibm.com>,
       Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
       Ingo Molnar <mingo@elte.hu>,
       Arnaldo Carvalho de Melo <acme@infradead.org>,
       utrace-devel <utrace-devel@redhat.com>,
       Frederic Weisbecker <fweisbec@gmail.com>,
       Masami Hiramatsu <mhiramat@redhat.com>,
       Maneesh Soni <maneesh@in.ibm.com>, Mark Wielaard <mjw@redhat.com>,
       LKML <linux-kernel@vger.kernel.org>
In-Reply-To: <4B543F93.3060509@redhat.com>
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Date: Mon, 18 Jan 2010 12:45:40 +0100
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On Mon, 2010-01-18 at 13:01 +0200, Avi Kivity wrote:
> If we reserve some address space, you don't add any heisenbugs (at 
> least, not any additional ones over emulation).  Even if we don't, 
> address space layout randomization means we're not keeping the address 
> space layout constant between runs anyway. 

Well, it still limits the number of probes to the reserved area. If you
want more you need to grow the area.. which then changes the state.

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