Re: [PATCH 11/18] maccess: remove strncpy_from_unsafe

[Linus Torvalds]

On Wed, May 13, 2020 at 4:21 PM Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
>
>
> For trace_kprobe.c current order (kernel -> user fallback) is preferred
> because it has another function dedicated for user memory.

Well, then it should just use the "strict" kernel-only one for the
non-user memory.

But yes, if there are legacy interfaces, then we might want to say
"these continue to work for the legacy case on platforms where we can
tell which kind of pointer it is from the bit pattern".

But we should likely at least disallow it entirely on platforms where
we really can't - or pick one hardcoded choice. On sparc, you really
_have_ to specify one or the other.

                  Linus