Re: [PATCH] ARM: add get_user() support for 8 byte types

Arnd Bergmann
2012-11-15T09:19:42Z

On Tuesday 13 November 2012, Russell King - ARM Linux wrote:
> You're missing something; that is one of the greatest powers of open
> source. The many eyes (and minds) effect. Someone out there probably
> has a solution to whatever problem, the trick is to find that person. :)
>
> I think we have a working solution for this for ARM. It won't be suitable
> for every arch, where they have 8-bit and 16-bit registers able to be
> allocated by the compiler, but for architectures where the minimum register
> size is 32-bit, what we have below should work.

I don't mind at all adding the extension to ARM, and I think it's pretty
cool that you guys actually found a working solution.

The part that worries me is that we are making architecture independent
code depend on a clever hack that may or may not be possible to implement
on a given architecture, and that most architecture maintainers wouldn't
know how to implement correctly even if it's possible.

Arnd