[RFC v7 03/21] um: move arch/um/os-Linux dir to tools/um/uml

[Johannes Berg]

On Tue, 2020-10-06 at 18:44 +0900, Hajime Tazaki wrote:
> This patch moves underlying OS dependent part under arch/um to tools/um
> directory so that arch/um code does not need to build host build
> facilities (e.g., libc).

Hmm. On the one hand, that build separation seems sensible, but on the
other hand this stuff *does* fundamentally belong to arch/um/, and it's
not a "tool" like basically everything else there that is a pure
userspace application to run *inside* the kernel, not *part of* it.

For that reason, I don't really like this much.


>  tools/um/uml/Build                            | 48 +++++++++++++++++++
>  tools/um/uml/drivers/Build                    | 10 ++++

Also, what's with the names here? What's wrong with "Makefile"?


I'm also not sure I see how this is built at all from the top level
Makefile? Oh. I think Anton said it doesn't ... that alone would be a
reason not to do it I guess.


So why do you think it must be under tools/? Even if you consider "lkl"
a "tool", that doesn't mean it must be there. I also consider a UML
binary ("linux") a "tool" in my simulation environment, etc.


And even LKL, which is the eventual goal here - why would you consider
that a "tool"? I don't think we should.

johannes