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Date:   Fri, 22 Jun 2018 00:10:06 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Fenghua Yu <fenghua.yu@intel.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
        Ashok Raj <ashok.raj@intel.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Rafael Wysocki <rafael.j.wysocki@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Alan Cox <alan@linux.intel.com>,
        Ravi V Shankar <ravi.v.shankar@intel.com>,
        Arjan van de Ven <arjan@infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>, x86 <x86@kernel.org>
Subject: Re: [RFC PATCH 00/16] x86/split_lock: Enable #AC exception for split
 locked accesses
Message-ID: <20180621221006.GC2494@hirez.programming.kicks-ass.net>
References: <1527435965-202085-1-git-send-email-fenghua.yu@intel.com>
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On Thu, Jun 21, 2018 at 03:00:03PM -0700, Fenghua Yu wrote:
> The control knob for firmware is to choose continuing firmware execution
> by disabling #AC split lock (default) or stopping firmware execution
> by enabling #AC for split lock. Stopping firmware execution may be useful
> in hard real time system to identify any split lock issue on the platform.

Having the option only allows broken firmware to continue to exist.
Limiting people in how they can use their machines.