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Date: Fri, 4 Dec 2015 11:56:17 +0100
From: Borislav Petkov <bp@alien8.de>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Amy Wiles <amy.l.wiles@intel.com>,
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        LKML <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] x86/rapl: Do not load in a guest
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On Fri, Dec 04, 2015 at 11:41:03AM +0100, Paolo Bonzini wrote:
> No, please don't.  Why do you need a wrmsr instead of a rdmsr?  If
> there's no RAPL domains, the device doesn't load.  On hypervisors,
> reading random MSRs is generally safe.

Well, we could not do anything, sure, that's an option too. It would
only be the annoying error message. Which is

	pr_err("no valid rapl domains found in package %d\n", rp->id);

I guess we can tone that down as apparently it is not an error to
not have valid rapl domains anymore. Maybe kill it altogether:
rapl_detect_topology() will propagate the error and the driver won't
load...

-- 
Regards/Gruss,
    Boris.

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