Re: [RFC PATCH 4/4] powerpc: mm/slb: blacklist symbols from kprobe

["Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>]

On 2016/11/18 08:36PM, Michael Ellerman wrote:
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:
> 
> > We can't really take a trap at this point. So, blacklist these symbols.
> >
> > Reported-by: Anton Blanchard <anton@samba.org>
> > Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> > ---
> >  arch/powerpc/mm/slb_low.S | 10 +++++-----
> >  1 file changed, 5 insertions(+), 5 deletions(-)
> >
> > diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
> > index c1c7456..c2bae92 100644
> > --- a/arch/powerpc/mm/slb_low.S
> > +++ b/arch/powerpc/mm/slb_low.S
> > @@ -30,7 +30,7 @@
> >   *	r9, r10, r11 are clobbered by this function
> >   * No other registers are examined or changed.
> >   */
> > -_GLOBAL(slb_allocate_realmode)
> > +_GLOBAL_NOKPROBE(slb_allocate_realmode)
> 
> I think I'd prefer we just leave these as is, and add somewhere nearby:
> 
> _ASM_NOKPROBE_SYMBOL(slb_allocate_realmode)
> 
> 
> It means someone reading the code doesn't need to worry about the
> nokprobe part, just to understand the function. It also means we need
> fewer macros :)

:)
Ok.

- Naveen