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From:   Logan Gunthorpe <logang@deltatee.com>
Message-ID: <34dc518d-b566-3e2a-8ad9-65d4f5d08a44@deltatee.com>
Date:   Thu, 1 Mar 2018 16:52:23 -0700
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Subject: Re: [PATCH v2 10/10] nvmet: Optionally use PCI P2P memory
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On 01/03/18 04:49 PM, Keith Busch wrote:
> On Thu, Mar 01, 2018 at 11:00:51PM +0000, Stephen  Bates wrote:
>>
>> P2P is about offloading the memory and PCI subsystem of the host CPU
>> and this is achieved no matter which p2p_dev is used.
> 
> Even within a device, memory attributes for its various regions may not be
> the same. There's a meaningful difference between writing to an NVMe CMB
> vs PMR, and a single device could have both. We don't want to lump these
> all together without knowing which region you're allocating from, right?

Yes, PMRs are a whole other beast. I have no idea what anyone is going 
to actually do with those yet. But no one is proposing to publish them 
as p2pmem with this code.

Logan