Re: [RFC PATCH] text_poke/ftrace/x86: Allow text_poke() to be called in early boot

[Steven Rostedt]

On Mon, 24 Oct 2022 18:02:32 -0700
Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:

> On Mon, Oct 24, 2022 at 5:21 PM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> >
> > It's all about updating read only pages that are executable with a shadow mm.  
> 
> Right. And it doesn't actually need the mm at all, all it wants is the
> kernel page tables. Which is why all the "dup_mmap()" stuff seems so
> wrong.
> 
> I suspect mm_alloc() does everything that VM actually needs.
> 
> IOW, it shouldn't have used the fork() helper, it should have used the
> execve() helper that actually starts out from a clean slate. Because a
> clean slate is exactly what that code wants.
> 
> No?
> 

Something to look into. But I'm guessing that's best for the next merge
window, and not for the -rc releases?

-- Steve