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Date: Wed, 4 Apr 2018 09:38:56 -0700
From: "Luck, Tony" <tony.luck@intel.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Patrick Bellasi <patrick.bellasi@arm.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Ingo Molnar <mingo@kernel.org>, Norbert Manthey <nmanthey@amazon.de>,
        Frederic Weisbecker <frederic@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: v4.16+ seeing many unaligned access in dequeue_task_fair() on
 IA64
Message-ID: <20180404163855.3obxjshmrlppzhdp@agluck-desk>
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On Wed, Apr 04, 2018 at 09:25:13AM +0200, Peter Zijlstra wrote:
> Right, I remember being careful with that. Which again brings me to the
> RANDSTRUCT thing, which will mess that up.

No RANDSTRUCT config options set for my build.

> Does the below cure things? It makes absolutely no difference for my
> x86_64-defconfig build, but it puts more explicit alignment constraints
> on things.

Yes. That fixes it. No unaligned traps with this patch applied.

Tested-by: Tony Luck <tony.luck@intel.com>

Thanks

-Tony