From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758934AbdEWEsz (ORCPT ); Tue, 23 May 2017 00:48:55 -0400 Received: from verein.lst.de ([213.95.11.211]:51757 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751771AbdEWEsx (ORCPT ); Tue, 23 May 2017 00:48:53 -0400 Date: Tue, 23 May 2017 06:48:51 +0200 From: Christoph Hellwig To: Thomas Gleixner Cc: Christoph Hellwig , linux-kernel@vger.kernel.org Subject: Re: [PATCH] kernel: mark all struct k_clock instances const Message-ID: <20170523044851.GA15761@lst.de> References: <20170515203213.25080-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 23, 2017 at 12:17:31AM +0200, Thomas Gleixner wrote: > On Mon, 15 May 2017, Christoph Hellwig wrote: > > > And keep a pointer to it instead of a copy in the posix_clocks array. > > > > Based on similar changes in the Grsecurity patchset, but redone from > > scratch including a few tweaks. > > Hmm, that adds another level of indirection, but yes, we can do it. > > > diff --git a/drivers/char/mmtimer.c b/drivers/char/mmtimer.c > > index 0e7fcb04f01e..e501403dd860 100644 > > --- a/drivers/char/mmtimer.c > > +++ b/drivers/char/mmtimer.c > > @@ -53,7 +53,7 @@ MODULE_LICENSE("GPL"); > > > > #define RTC_BITS 55 /* 55 bits for this implementation */ > > > > -static struct k_clock sgi_clock; > > +static const struct k_clock sgi_clock; > > Bah. This mmtimer which is used by 3 people in the world requires that we > keep the register_clock() function around after init and even export it. We can require the driver to be built into the kernel, which seems pretty reasonable for a timer. It's only selectable on IA64 anyway.