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Date: Mon, 21 Apr 2008 17:55:34 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Roland McGrath <roland@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Jan Beulich <jbeulich@novell.com>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: prevent unconditional writes to DebugCtl MSR
Message-ID: <20080421155534.GA1284@elte.hu>
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* Roland McGrath <roland@redhat.com> wrote:

> If TIF_DEBUGCTLMSR is ever set on a machine without the support, that 
> is a bug we should diagnose earlier.  If you want some paranoia, then 
> keep update_debugctlmsr but make it do:
> 
> 	BUG_ON(boot_cpu_data.x86 < 6);
> 
> instead.

agreed. Jan, wanna send a fix for this?

	Ingo