On Tue, Dec 21, 2021 at 06:40:30PM +0100, David Hildenbrand wrote:

2) is certainly the cherry on top. But it just means that R/O pins don't
have to be the weird kid. And yes, achieving 2) would require
FAULT_FLAG_EXCLUSIVE / FAULT_FLAG_UNSHARED, but it would really 99% do
what existing COW logic does, just bypass the "map writable" and
"trigger write fault" semantics.

I still don't agree with this - when you come to patches can you have
this work at the end and under a good cover letter? Maybe it will make
more sense then.

Thanks,
Jason