From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH V2 2/3] perf protect LBR when Intel PT is enabled.
Date: Thu, 3 Jul 2014 17:52:37 +0200
Message-ID: <20140703155237.GQ5714@two.firstfloor.org>
References: <1404324855-15166-1-git-send-email-kan.liang@intel.com>
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 <20140703073321.GU19379@twins.programming.kicks-ass.net>
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Cc: kan.liang@intel.com, linux-kernel@vger.kernel.org,
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To: Peter Zijlstra <peterz@infradead.org>
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> If there's active LBR users out there, we should refuse to enable PT and
> vice versa. 

This doesn't work, e.g. hardware debuggers can take over at any time.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.