From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out1-smtp.messagingengine.com ([66.111.4.25]:47087 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S937015AbdDSPS2 (ORCPT ); Wed, 19 Apr 2017 11:18:28 -0400 Date: Wed, 19 Apr 2017 17:18:18 +0200 From: Greg KH To: Kees Cook Cc: Arjan van de Ven , Ben Hutchings , stable , Thomas Gleixner , John Stultz Subject: Re: [stable] Removing or restricting timer_stats Message-ID: <20170419151818.GA27487@kroah.com> References: <1492482305.2409.135.camel@decadent.org.uk> <20170419115018.GH27378@kroah.com> <20170419145709.GA19812@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: On Wed, Apr 19, 2017 at 08:01:18AM -0700, Kees Cook wrote: > On Wed, Apr 19, 2017 at 7:57 AM, Greg KH wrote: > > On Wed, Apr 19, 2017 at 07:54:34AM -0700, Kees Cook wrote: > >> On Wed, Apr 19, 2017 at 4:50 AM, Greg KH wrote: > >> > On Tue, Apr 18, 2017 at 03:25:05AM +0100, Ben Hutchings wrote: > >> >> The timer_stats feature was removed upstream by: > >> >> > >> >> commit dfb4357da6ddbdf57d583ba64361c9d792b0e0b1 > >> >> Author: Kees Cook > >> >> Date: Wed Feb 8 11:26:59 2017 -0800 > >> >> > >> >> time: Remove CONFIG_TIMER_STATS > >> >> > >> >> I'm hesitant to propose removing a feature in stable, even if it is > >> >> redundant. What I've done for Debian stable is to restrict it to the > >> >> initial pid namespace (see attached). Would that be a reasonable > >> >> alternative change for stable branches? > >> > > >> > I don't mind removing things in stable as that's what happened in > >> > Linus's tree, and it was removed for a reason. We've done it before, > >> > and I'm more hesitant to apply something that works a bit > >> > "differently". > >> > > >> > Kees, any objection for me just taking the "full" patch in the stable > >> > kernels? > >> > >> Arjan said it would break powertop, IIRC. > > > > So we broke it in 4.11? That doesn't seem to sound reasonable, how are > > you getting away with that? :) > > tglx seemed to think that the same information was available elsewhere? > > Thread was here: https://patchwork.kernel.org/patch/9561519/ Getting the same info elsewhere is fine, breaking working tools is not. I'm running powertop on 4.11-rc6 here and there doesn't seem to be anything "broken". And, as this is removed there, I don't see why backporting it should matter. Either it breaks someone, or it doesn't, the kernel version shouldn't matter... thanks, greg k-h