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Date:   Mon, 14 Jun 2021 09:12:23 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Tianyu Lan <ltykernel@gmail.com>
Cc:     Christoph Hellwig <hch@lst.de>, kys@microsoft.com,
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Subject: Re: [RFC PATCH V3 08/11] swiotlb: Add bounce buffer remap address
 setting function
Message-ID: <20210614071223.GA30171@lst.de>
References: <20210530150628.2063957-1-ltykernel@gmail.com> <20210530150628.2063957-9-ltykernel@gmail.com> <20210607064312.GB24478@lst.de> <48516ce3-564c-419e-b355-0ce53794dcb1@gmail.com>
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On Mon, Jun 07, 2021 at 10:56:47PM +0800, Tianyu Lan wrote:
> These addresses in extra address space works as system memory mirror. The 
> shared memory with host in Isolation VM needs to be accessed via extra 
> address space which is above shared gpa boundary.

Why?