Re: [PATCH v5 2/5] powerpc: kretprobes: override default function entry offset

From: Naveen N. Rao
Date: Wed Mar 08 2017 - 11:00:11 EST

Hi Michael,

On 2017/03/08 09:43PM, Michael Ellerman wrote:
> "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxxxxxxx> writes:
> > With ABIv2, we offset 8 bytes into a function to get at the local entry
> > point.
> >
> > Acked-by: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxxxxxxxxxx>
> > Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> > Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
> > ---
> > arch/powerpc/kernel/kprobes.c | 9 +++++++++
> > 1 file changed, 9 insertions(+)
> I'm OK with this change, and I'm happy for it to go with the rest of the
> series via acme's tree:
> Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> But, you've also sent a series to do KPROBES_ON_FTRACE, and that also
> touches this function, see the 2nd to last hunk at:
> If this goes via acme's tree it will be awkward for me to merge the
> series above via the powerpc tree.

Ah yes, indeed.

> So we could do topic branches and so on, or we could just drop this
> patch from this series, and I'll merge it as part of the other series.
> It won't do anything useful until it's merged with a tree that also has
> the rest of this series. Or something else I haven't thought of.

The arch-independent change that this depends on has been picked up by
Arnaldo and pushed to Ingo:

I'm guessing this will go into v4.11? In which case, this powerpc patch
should also go in. Otherwise kretprobes will be broken on powerpc64le.

I wasn't sure if you were planning on picking up KPROBES_ON_FTRACE for
v4.11. If so, it would be good to take this patch through the powerpc
tree. Otherwise, this can go via Ingo's tree.