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Date:   Fri, 22 Jun 2018 00:11:14 +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
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On Thu, Jun 21, 2018 at 03:00:03PM -0700, Fenghua Yu wrote:
> The control knob for user is to choose killing the process (default) or
> re-executing the faulting instruction without blocking the process.
> Re-executing the instruction maybe be useful in platforms that run
> well controlled apps with less split locks.

Just fix the applications. I doubt there will be many, many other
platforms will already SIGBUS on unaligned access, atomic or not.