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Date: Thu, 8 Jun 2017 00:58:29 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Tom Lendacky <thomas.lendacky@amd.com>
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Subject: Re: [PATCH v6 25/34] swiotlb: Add warnings for use of bounce buffers
 with SME
Message-ID: <20170608075829.GA2446@infradead.org>
References: <20170607191309.28645.15241.stgit@tlendack-t1.amdoffice.net>
 <20170607191732.28645.42876.stgit@tlendack-t1.amdoffice.net>
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On Wed, Jun 07, 2017 at 02:17:32PM -0500, Tom Lendacky wrote:
> Add warnings to let the user know when bounce buffers are being used for
> DMA when SME is active.  Since the bounce buffers are not in encrypted
> memory, these notifications are to allow the user to determine some
> appropriate action - if necessary.

And what would the action be?  Do we need a boot or other option to
disallow this fallback for people who care deeply?