Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752119AbcCGDaG (ORCPT ); Sun, 6 Mar 2016 22:30:06 -0500 Received: from ozlabs.org ([103.22.144.67]:45367 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751341AbcCGD36 (ORCPT ); Sun, 6 Mar 2016 22:29:58 -0500 Message-ID: <1457321396.19197.3.camel@ellerman.id.au> Subject: Re: [PATCH][v4] livepatch/ppc: Enable livepatching on powerpc From: Michael Ellerman To: Miroslav Benes Cc: Petr Mladek , linuxppc-dev@ozlabs.org, jeyu@redhat.com, jkosina@suse.cz, linux-kernel@vger.kernel.org, rostedt@goodmis.org, kamalesh@linux.vnet.ibm.com, duwe@lst.de, live-patching@vger.kernel.org, Torsten Duwe Date: Mon, 07 Mar 2016 14:29:56 +1100 In-Reply-To: References: <1457023921-2051-1-git-send-email-pmladek@suse.com> <1457078325.20076.1.camel@ellerman.id.au> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5-1ubuntu3.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1568 Lines: 42 On Fri, 2016-03-04 at 10:31 +0100, Miroslav Benes wrote: > On Fri, 4 Mar 2016, Michael Ellerman wrote: > > On Thu, 2016-03-03 at 17:52 +0100, Petr Mladek wrote: > > > > > 3. Added an error message when including > > > powerpc/include/asm/livepatch.h without HAVE_LIVEPATCH > > > > I don't know why we want to do that, I don't see how it is helpful. It doesn't > > even do what it says: > > > > > +#ifdef CONFIG_LIVEPATCH > > ... > > > +#else /* CONFIG_LIVEPATCH */ > > > +#error Include linux/livepatch.h, not asm/livepatch.h > > > +#endif /* CONFIG_LIVEPATCH */ > > > > If I turn on CONFIG_LIVEPATCH then I can quite happily include asm/livepatch.h > > and not get an error. So the check doesn't do what the message suggests. > > Well, yes. I looked into the archives to find if there was a reason to > even introduce it. It was not. It came up during a review process of the > livepatching patch set somehow and we left it there. I only changed the > error message to the mentioned one because we deemed it was better. Thanks for looking into it. > > And on x86 & s390 it does: > > > > #else > > #error Live patching support is disabled; check CONFIG_LIVEPATCH > > #endif > > This is the old message. See 383bf44d1a8b ("livepatch: change the error > message in asm/livepatch.h header files"). > > Anyway, it really does not mean much. I'll send a patch for s390 and x86 > to remove it completely in a minute. Thanks. I know it's not a big deal, but the kernel is complicated enough without extra code we don't really need :) cheers