On Friday, July 14th, 2023 at 12:31, Simon Ser <contact@xxxxxxxxxxx> wrote: > Before this patch, 0..63 are for primary, 64..127 are for control (never > exposed by the kernel), 128..191 are for render, 2048..2112 are for accel. > After this patch, 0..127 are for primary, 64..191 are for control (never > exposed by the kernel), 128..255 are for render, 2048..2176 are for accel. Correction: reading the code, accel is handled separately. Additional find: the kernel creates sysfs control nodes because old user-space reads them to figure out whether a device is DRIVER_MODESET.