> I know I won't be able to convince you but I want to say that I think > your arguments for full userspace open source are not really > technical.
There is more to keeping a kernel going than technical argument unfortunately. I guess the question for Greg, Olof etc, is do we care about Linux the kernel, or Linux the open source ecosystem, if the former, these sort of accelerator shim drivers are fine, useless to anyone who doesn't have all the magic hidden userspace, and impossible to support for anyone else, if the latter, we should leave the cost of maintenance to the company benefiting from it and leave maintaining it out of tree. Simple question like If I plug your accelerator into Power or ARM64, where do I get the port of your userspace to use it? I'm not the final arbiter on this sort of thing, but I'm definitely going to make sure that anyone who lands this code is explicit in ignoring any experience we've had in this area and in the future will gladly accept "I told you so" :-) Dave.