linux-kernel - Re: [PATCH v9 4/5] x86/xsave: Make XSAVE check the base CPUID features before enabling

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Message-ID: <20171013174850.GR5109@tassilo.jf.intel.com>
Date:   Fri, 13 Oct 2017 10:48:50 -0700
From:   Andi Kleen <ak@...ux.intel.com>
To:     Ingo Molnar <mingo@...nel.org>
Cc:     Andi Kleen <andi@...stfloor.org>, x86@...nel.org,
        linux-kernel@...r.kernel.org, Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH v9 4/5] x86/xsave: Make XSAVE check the base CPUID
 features before enabling

> > +	/*
> > +	 * Clear XSAVE features that are disabled in the normal CPUID.
> > +	 */
> > +	for (i = 0; i < ARRAY_SIZE(xsave_cpuid_features); i++) {
> > +		if (!boot_cpu_has(xsave_cpuid_features[i]))
> > +			xfeatures_mask &= ~BIT(i);
> > +	}
> > +
> >  	xfeatures_mask &= fpu__get_supported_xfeatures_mask();
> >  
> >  	/* Enable xstate instructions to be able to continue with initialization: */
> 
> This patch has similar problems to the ones I reported against 2/5.

I'm not clear what I'm supposed to change here. The array cannot be __initdata
because it is used at cpu hotplug. Nothing else seems to apply.

-Andi