From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] iommu/vt-d: Remove unnecassary qi clflushes
Date: Mon, 27 Jun 2016 13:30:15 +0200
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To: Nadav Amit <namit-pghWNbHTmq7QT0dZR+AlfA@public.gmane.org>
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On Fri, Jun 24, 2016 at 06:13:14AM -0700, Nadav Amit wrote:
> According to the manual: "Hardware access to ...  invalidation queue ...
> are always coherent."
> 
> Remove unnecassary clflushes accordingly.

It is one thing what the spec says and another how hardware really
behaves. Have you tested this on (potentially really old) VT-d machines
to make sure the spec is _always_ right here?


	Joerg