Date: Fri, 5 Jul 2013 23:22:35 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Alex Shi <alex.shi@intel.com>,
        hpa@linux.intel.com, tim.c.chen@linux.intel.com,
        linux-kernel@vger.kernel.org, andi.kleen@intel.com, mingo@elte.hu
Subject: Re: [URGENT rfc patch 0/3] tsc clocksource bug fix
Message-ID: <20130705212235.GU23916@twins.programming.kicks-ass.net>
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 <20130705143833.GT23916@twins.programming.kicks-ass.net>
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On Fri, Jul 05, 2013 at 05:24:09PM +0200, Thomas Gleixner wrote:
> See arch/x86/kernel/tsc.c
> 
> We disable the watchdog for the TSC when tsc_clocksource_reliable is
> set.
> 
> tsc_clocksource_reliable is set when:
> 
>  - you add tsc=reliable to the kernel command line

Ah, I didn't know about that one, useful.

>  - boot_cpu_has(X86_FEATURE_TSC_RELIABLE)
>  
>    X86_FEATURE_TSC_RELIABLE is a software flag, set by vmware and
>    moorsetown. So all other machines keep the watchdog enabled.

Right.. I knew it was enabled on my machines even though they normally
have usable TSC.
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