Re: [PATCH] x86: Allow user accesses to the base of the guard page

[Linus Torvalds]

On Sat, 23 Nov 2024 at 14:36, David Laight <David.Laight@xxxxxxxxxx> wrote:
>
> The problem is that it is valid to pass a buffer that ends right
> at the end of valid user memory.

There's a difference between "valid" and "we care".

This is way past that case. The only possible reason for that
zero-byte thing at the end of the address space is somebody actively
looking for some edge case, not a real use.

               Linus