On Fri, Sep 20, 2024 at 07:35:28PM +0530, Srujana Challa wrote: > This patchset introduces support for an UNSAFE, no-IOMMU mode in the > vhost-vdpa driver. When enabled, this mode provides no device isolation, > no DMA translation, no host kernel protection, and cannot be used for > device assignment to virtual machines. It requires RAWIO permissions > and will taint the kernel. > > This mode requires enabling the "enable_vhost_vdpa_unsafe_noiommu_mode" > option on the vhost-vdpa driver and also negotiate the feature flag > VHOST_BACKEND_F_NOIOMMU. This mode would be useful to get > better performance on specifice low end machines and can be leveraged > by embedded platforms where applications run in controlled environment.
... and is completely broken and dangerous.
