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To: Marta Rybczynska <mrybczyn@kalray.eu>
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From: Logan Gunthorpe <logang@deltatee.com>
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Date: Tue, 25 Apr 2017 10:58:40 -0600
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Subject: Re: [RFC 1/8] Introduce Peer-to-Peer memory (p2pmem) device
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On 25/04/17 05:58 AM, Marta Rybczynska wrote:
> I would add one issue that doesn't seem to be addressed: in my experience
> P2P doesn't work when IOMMU activated. It works best with deactivation at
> the BIOS level, even the kernel options are not enough in some cases.

Well this would likely be addressed by 'arch_p2p_cross_segment' as
proposed by Jason.

Logan