On 2020-06-12 17:02, Robert Crowston wrote: > What is the physical address to which the xhci controller is performing DMA? It needs to be in the lower 3 GB of the physical address space. The XHCI doesn't set any limits on the DMA location, but it easily can. We have a quirk for 32-bits: set hw.usb.xhci.dma32=1 From the loader. --HPS