Re: [patch V4 part 3 01/29] x86/traps: Mark fixup_bad_iret() noinstr

Steven Rostedt
2020-05-13T01:51:13Z

On Fri, 8 May 2020 17:39:00 -0700
Andy Lutomirski <luto@kernel.org> wrote:

> On Tue, May 5, 2020 at 7:15 AM Thomas Gleixner <tglx@linutronix.de> wrote:
> >
> > This is called from deep entry ASM in a situation where instrumentation
> > will cause more harm than providing useful information.
> >
>
> Acked-by: Andy Lutomirski <luto@kernel.org>
>
> Maybe add to changelog:
>
> Switch from memmove() to memcpy() because memmove() can't be called
> from noinstr code.

Yes please, because I was about to say that there was changes that
didn't seem to fit the change log.

I would also add a comment in the code saying that we need the temp
variable to use memcpy as memmove can't be used in noinstr code.

-- Steve