On 13/09/19 17:32, Robin Murphy wrote: > Oh, that bit of usbdev_mmap() is already known to be pretty much totally > bogus for various reasons - there have been a few threads about it, of > which I think [1] is both the most recent and the most informative. > There was another patch[2], but that might have stalled (and might need > reworking with additional hcd_uses_dma() checks anyway). Neither is enough, see my reply to Alan. Memory from kmalloc just *cannot* be passed down to remap_pfn_range, dma_mmap_coherent or anything like that. It's a simple alignment issue. Paolo
