17 Dec
2021
17 Dec
'21
9:50 p.m.
On Fri, Dec 17, 2021 at 1:47 PM David Hildenbrand david@redhat.com wrote:
For now I have not heard a compelling argument why the mapcount is dubious, I repeat:
- mapcount can only increase due to fork()
- mapcount can decrease due to unmap / zap
We can protect from the transtition == 1 -> >1 using the mmap_lock.
For COW the mapcount is the only thing that matters *if we take GUP* out of the equation. And that's exactly what we
What do you have against just doing what we already do in other parts, that a/b thing?
Which avoids the whole mmap_sem issue. That was a big issue for the rdma people, afaik.
Linus