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Date: Wed, 15 Feb 2017 09:56:21 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
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        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Borislav Petkov <bp@suse.de>, Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 2/2] perf/x86/intel/pt: Fail event creation if VMX
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On Wed, Feb 15, 2017 at 10:34:58AM +0200, Alexander Shishkin wrote:

> Well, we can't make the limitation go away. You'll still have to stop
> kvms to get any 'meaningful' PT data.

Why would you need to stop all VMs in order to get your !VM data? Sure,
you get black holes where the VM runs, but we should be able to see
everything else.