Re: klp: remove superfluous errors in asm/livepatch.h

From: Jessica Yu
Date: Tue Mar 08 2016 - 16:28:31 EST

+++ Jiri Kosina [06/03/16 22:13 +0100]:
On Fri, 4 Mar 2016, Josh Poimboeuf wrote:

> There is an #error in asm/livepatch.h for both x86 and s390 in
> !CONFIG_LIVEPATCH cases. It does not make much sense as pointed out by
> Michael Ellerman. One can happily include asm/livepatch.h with
> CONFIG_LIVEPATCH. Remove it as useless.
> Suggested-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Signed-off-by: Miroslav Benes <mbenes@xxxxxxx>

Looks fine to me.

Thanks. I consider this to be your Ack then :) (if you disagree, please
shout loudly).

While we're at it, do we even need the '#ifdef CONFIG_LIVEPATCH' in
these files? And in include/linux/livepatch.h?

You are right, this seems indeed completely unnecessary. I'll remove it
for 4.6 as well, if noone has any objections.

Hm, I should've caught this earlier, but the notifier cleanup patch
that removes the livepatch module notifier had kernel/module.c include
livepatch.h for the klp_module_{coming,going} function stubs in the
!CONFIG_LIVEPATCH case. See here:

Looking back, I now don't think it makes sense for module.c to include
all those livepatch definitions in the first place, since all it
needed was the klp_module_{coming,going} declarations. I guess my
question is, since we've removed the #ifdef CONFIG_LIVEPATCH blocks
from livepatch.h, where might be a better place for the
klp_module_{coming,going} stubs? Perhaps they could go in module.h