<div dir="ltr">When working with dumb buffers, DRM_IOCTL_MODE_MAP_DUMB and mmap works fine on Intel, but the mmap call fails on Radeon, Nouveau, and VMWGFX. I you look at the source for the xorg moderating driver, it only uses the dumb buffer IOCTL (i.e. it’s not using LibKMS), and if you look at the kernel source code for the dumb buffer IOCTLs for each of the Radeon, Nouveau, and VMWGFX drivers, they all implement the functions. Furthermore all of the IOCTLs succeed without error. Its only when you attempt to map the memory, that you get an error of “Invalid Argument”. Here is my map call: mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, map_arg.offset) Is this a bug, or is there a different way to map the dumb buffers for these drivers other than LibKMS. Thanks, - Rian </div>