From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Borntraeger Subject: Re: Is THREAD_INFO_IN_TASK appropriate for -mm for 4.8? Date: Tue, 19 Jul 2016 10:25:42 +0200 Message-ID: <578DE406.9060902@de.ibm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:49606 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752596AbcGSIZv (ORCPT ); Tue, 19 Jul 2016 04:25:51 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u6J8NuMO060113 for ; Tue, 19 Jul 2016 04:25:49 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0b-001b2d01.pphosted.com with ESMTP id 2495r89dy0-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 19 Jul 2016 04:25:49 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 19 Jul 2016 09:25:47 +0100 In-Reply-To: Sender: linux-arch-owner@vger.kernel.org List-ID: To: Andy Lutomirski , Andrew Morton , x86 , "linux-kernel@vger.kernel.org" , Borislav Petkov , Linux Arch Mailing List , Oleg Nesterov , "linux-s390@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" On 07/19/2016 01:47 AM, Andy Lutomirski wrote: > Hi all- > > There are four core patches needed for the THREAD_INFO_IN_TASK thing, > and they apply cleanly to -mm now. The x86 patch to flip the feature > on does not apply cleanly anywhere because it depends on changes in > -tip *and* in -mm. I'd like to get all of this as well as the rest of > the vmap-stacks stuff in by 4.9, but I'm wondering if it might make > sense to get the core THREAD_INFO_IN_TASK stuff into -mm for 4.8 > instead. > > Pros: > - It reduces the amount of core code that -tip will have to carry until 4.9. > - It may benefit other architectures. Christian Borntraeger > expressed an interest in enabling the feature for s390, but it'll be > awkward for him until the core bit landed. Similarly, arm64 seems to > be interested. I have not yet talked to Martin/Heiko about this, so not sure yet if and when s390 is going to use this - so no pressure from our side yet.