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Date: Thu, 10 Jan 2008 13:40:41 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Harvey Harrison <harvey.harrison@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86: Remove ifdef from step.c
Message-ID: <20080110124041.GA15156@elte.hu>
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* Harvey Harrison <harvey.harrison@gmail.com> wrote:

> @@ -148,11 +148,7 @@ static void write_debugctlmsr(struct task_struct *child, unsigned long val)
>  	if (child != current)
>  		return;
>  
> -#ifdef CONFIG_X86_64
> -	wrmsrl(MSR_IA32_DEBUGCTLMSR, val);
> -#else
>  	wrmsr(MSR_IA32_DEBUGCTLMSR, val, 0);
> -#endif

doesnt this break 64-bit? 'val' is 64-bit, but wrmsr truncates it to 
32-bit? [while wrmsrl() kept the full 64 bits]

	Ingo