Re: [EXTERNAL] Re: [PATCH v2 0/2] vhost-vdpa: Add support for NO-IOMMU mode

Christoph Hellwig
2024-10-17T06:19:21Z

On Wed, Oct 16, 2024 at 05:28:27PM +0000, Srujana Challa wrote:
> When using the DPDK virtio user PMD, we’ve noticed a significant 70%
> performance improvement when IOMMU is disabled on specific low-end
> x86 machines. This performance improvement can be particularly
> advantageous for embedded platforms where applications operate in
> controlled environments. Therefore, we believe supporting the intel_iommu=off
> mode is beneficial.

While making the system completely unsafe to use. Maybe you should
fix your stack to use the iommu more itelligently instead?