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Date: Mon, 28 Nov 2016 15:06:18 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Kyle Huey <me@kylehuey.com>
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Subject: Re: [PATCH v13 6/8] x86/arch_prctl: Add ARCH_[GET|SET]_CPUID
In-Reply-To: <20161128030521.4423-7-khuey@kylehuey.com>
Message-ID: <alpine.DEB.2.20.1611281437130.3512@nanos>
References: <20161128030521.4423-1-khuey@kylehuey.com> <20161128030521.4423-7-khuey@kylehuey.com>
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On Sun, 27 Nov 2016, Kyle Huey wrote:
> +DEFINE_PER_CPU(u64, msr_misc_features_shadow);
> +
> +static void set_cpuid_faulting(bool on)
> +{
> +	u64 msrval;
> +
> +	DEBUG_LOCKS_WARN_ON(!irqs_disabled());

The arch_prctl code path does not have interrupts disabled and there is no
reason why it should have.

Thanks,

	tglx