Re: [PATCH 2/4] x86: get rid of KERNEL_STACK_OFFSET

Ingo Molnar
2015-02-26T11:43:00Z

* Andy Lutomirski <luto@amacapital.net> wrote:

> >> I added that in and applied this patch.
> >
> > So this is not just slightly buggy, it's fundamentally
> > wrong as well as it removes the possibility of an RSP
> > value optimization from the 64-bit path, see my
> > previous mail.
>
> This is just trying to check that the function is
> executing on the per-thread stack. It was correct (and
> fairly heavily tested by Tony) wither KERNEL_STACK_OFFSET
> being nonzero, but we're checking the wrong page if
> KERNEL_STACK_OFFSET becomes zero.
>
> I don't think I understand your objection to this bit.

I object to the KERNEL_STACK_OFFSET removal patch you fixed
here, not to the add-on fix in particular (which is correct
in the context of that patch).

Thanks,

Ingo