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Date: Tue, 22 Oct 2019 18:33:21 -0700
From: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Subject: [MODERATED] Re: [PATCH v7 04/10] TAAv7 4
Message-ID: <20191023013321.GC30440@guptapadev.amr>
References: <cover.1571688957.git.pawan.kumar.gupta@linux.intel.com>
 <20191022165112.GK31458@zn.tnic>
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To: speck@linutronix.de
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On Tue, Oct 22, 2019 at 06:51:12PM +0200, speck for Borislav Petkov wrote:
> > +static void __init taa_select_mitigation(void)
> > +{
> > +	u64 ia32_cap = x86_read_arch_cap_msr();
> 
> Do that MSR access...
> 
> > +
> > +	if (!boot_cpu_has_bug(X86_BUG_TAA)) {
> > +		taa_mitigation = TAA_MITIGATION_OFF;
> > +		return;
> > +	}
> 
> ... here.
> 

Is it okay to move x86_read_arch_cap_msr() further down just before its needed?

+       ia32_cap = x86_read_arch_cap_msr();
+
	if ((ia32_cap & ARCH_CAP_MDS_NO) &&
			!(ia32_cap & ARCH_CAP_TSX_CTRL_MSR))
		taa_mitigation = TAA_MITIGATION_UCODE_NEEDED;

Thanks,
Pawan