Date: Sat, 6 Jan 2018 09:57:29 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Dave Hansen <dave.hansen@intel.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andi Kleen <ak@linux.intel.com>,
        Arjan Van De Ven <arjan.van.de.ven@intel.com>,
        David Woodhouse <dwmw@amazon.co.uk>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 8/8] x86: Use IBRS for firmware update path
Message-ID: <20180106085729.GC4380@kroah.com>
References: <cover.1515204614.git.tim.c.chen@linux.intel.com>
 <cda39b693d0fec41bd65aa17e7d7ea6bcbf48cc0.1515204614.git.tim.c.chen@linux.intel.com>
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On Fri, Jan 05, 2018 at 06:12:23PM -0800, Tim Chen wrote:
> +void unprotected_firmware_begin(void)
> +{
> +	if (firmware_ibrs) {
> +		__disable_indirect_speculation();
> +	} else {
> +		/*
> +		 * rmb prevent unwanted speculation when we
> +		 * are setting IBRS
> +		 */
> +		rmb();
> +	}
> +}
> +EXPORT_SYMBOL_GPL(unprotected_firmware_begin);

What modules need these functions?

And again, if they are needed, we need a better naming scheme for them.
Prefix them all with "firmware_" perhaps to make it a bit nicer?

thanks,

greg k-h