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From: Shivapriya  Hiremath <shivpri.b@gmail.com>
Date: Mon, 20 Oct 2014 14:58:54 -0700
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Subject: [dpdk-dev] Why do we need iommu=pt?
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Hi,

My question is that if the Poll mode  driver used the DMA kernel interface
to set up its mappings appropriately, would it still require that iommu=pt
be set?
What is the purpose of setting iommu=pt ?

Thank you.