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Date: Thu, 1 Mar 2018 16:49:30 -0700
From: Keith Busch <keith.busch@intel.com>
To: Stephen Bates <sbates@raithlin.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>, Logan Gunthorpe <logang@deltatee.com>,
        Sagi Grimberg <sagi@grimberg.me>,
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Subject: Re: [PATCH v2 10/10] nvmet: Optionally use PCI P2P memory
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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?