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Date:   Fri, 4 May 2018 12:45:39 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Luwei Kang <luwei.kang@intel.com>, kvm@vger.kernel.org,
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        x86@kernel.org, rkrcmar@redhat.com, linux-kernel@vger.kernel.org,
        joro@8bytes.org, chao.p.peng@linux.intel.com
Subject: Re: [PATCH v7 06/13] KVM: x86: Add Intel Processor Trace
 virtualization mode
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On Thu, May 03, 2018 at 04:38:23PM +0300, Alexander Shishkin wrote:
> On Thu, May 03, 2018 at 02:50:12PM +0200, Paolo Bonzini wrote:

> > And you still need the module parameter to decide
> > whether the host is _allowed_ to cause incomplete traces in the guest.
> 
> Or rather a parameter to decide who wins in case both host and guest want
> to trace the guest. That's arguably better than having different versions of
> PT in the guest depending on a module parameter setting.

Yes, that sounds like a much better approach.