On Tue, Apr 30, 2019 at 12:27:02PM +0100, Robin Murphy wrote: > > Hmm, I don't think we need the DMA mask for the MSI mapping, this > > should probably always use a 64-bit mask. > > If that were true then we wouldn't need DMA masks for regular mappings > either. If we have to map the MSI doorbell at all, then we certainly have to > place it at an IOVA that the relevant device is actually capable of > addressing. Well, as shown by the patch below we don't even look at the DMA mask for the MSI page - we just allocate from bottom to top.