On Wed, Sep 29, 2021 at 12:38:35AM +0000, Tian, Kevin wrote: > /* If set the driver must call iommu_XX as the first action in probe() or > * before it attempts to do DMA > */ > bool suppress_dma_owner:1; It is not "attempts to do DMA" but more "operates the physical device in any away" Not having ownership means another entity could be using user space DMA to manipulate the device state and attack the integrity of the kernel's programming of the device. Jason
