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From:   Christoph Hellwig <hch@lst.de>
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Subject: Re: [PATCH 08/12] x86: centralize setting SWIOTLB_FORCE when guest
 memory encryption is enabled
Message-ID: <20220301114335.GA2881@lst.de>
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On Tue, Mar 01, 2022 at 11:39:29AM +0000, Andrew Cooper wrote:
> This isn't really "must".  The guest is perfectly capable of sharing
> memory with the hypervisor.
> 
> It's just that for now, bounce buffering is allegedly faster, and the
> simple way of getting it working.

Yeah, I guess you щould just share/unshare on demand.  But given that
this isn't implemented it is a must in the current kernel.  But if
you want a different wording suggest one and I'll put it in.