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From: Shahaf Shuler <shahafs@mellanox.com>
To: Andrew Theurer <atheurer@redhat.com>, "users@dpdk.org" <users@dpdk.org>
Subject: Re: [dpdk-users] Mellanox mlx5 PMD: is IOMMU used?
Date: Thu, 8 Feb 2018 06:22:02 +0000	[thread overview]
Message-ID: <VI1PR05MB3149213C7B62589A870EB50AC3F30@VI1PR05MB3149.eurprd05.prod.outlook.com> (raw)
In-Reply-To: <CAD5-U7TaOuSW7rmHatNJ9gBeKbhHXEnPurWuNS+eGxnHp8VOdA@mail.gmail.com>

Hi Andrew

Thursday, February 8, 2018 5:03 AM, Andrew Theurer:
> My understanding is that the vfio-pci kernel module cannot be loaded for
> Mellanox adapters, and the mlx5_core must stay loaded in the kernel.  Does
> that mean there is no IOMMU used?

Yes, the chip set IOMMU is not being used. it can be used, but this is not a strict requirement to enforce memory protection. 
Memory protection and isolation are enforced by the kernel driver and the device.

Mellanox devices has translation engine from VA->PA for registered addresses. 
The PMD is working with VA, and registering them to the device through mlx5_core which enforce the protection, pin the memory (If needed) and provide the PA to the device.  

> 
> Thanks,
> 
> -Andrew

      reply	other threads:[~2018-02-08  6:22 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-08  3:03 Andrew Theurer
2018-02-08  6:22 ` Shahaf Shuler [this message]

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