From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 1A11A486 for ; Thu, 14 Jul 2016 09:54:48 +0000 (UTC) Received: from mail-io0-f182.google.com (mail-io0-f182.google.com [209.85.223.182]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 7F81BCB for ; Thu, 14 Jul 2016 09:54:47 +0000 (UTC) Received: by mail-io0-f182.google.com with SMTP id m101so70663877ioi.2 for ; Thu, 14 Jul 2016 02:54:47 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <57875FF1.7020206@linaro.org> References: <1468058721.2557.9.camel@HansenPartnership.com> <0ED98206-0A66-48A4-B5A4-A0BC53FDBF05@primarydata.com> <1468114447.2333.12.camel@HansenPartnership.com> <1468115770.2333.15.camel@HansenPartnership.com> <718BE1FD-6169-4205-A905-53F997D5943A@primarydata.com> <5785C80F.4030707@linaro.org> <20160713090739.GA18037@kroah.com> <578635F6.9040601@linaro.org> <20160714011905.GA20986@kroah.com> <57875FF1.7020206@linaro.org> From: Ard Biesheuvel Date: Thu, 14 Jul 2016 11:54:46 +0200 Message-ID: To: Alex Shi Content-Type: text/plain; charset=UTF-8 Cc: James Bottomley , "ksummit-discuss@lists.linuxfoundation.org" , Trond Myklebust Subject: Re: [Ksummit-discuss] [CORE TOPIC] kernel unit testing List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 14 July 2016 at 11:48, Alex Shi wrote: > > > On 07/14/2016 10:19 AM, Greg KH wrote: >> >> On Wed, Jul 13, 2016 at 09:37:10PM +0900, Alex Shi wrote: >>> >>> >>> On 07/13/2016 06:07 PM, Greg KH wrote: >>>> >>>> On Wed, Jul 13, 2016 at 01:48:15PM +0900, Alex Shi wrote: >>>>> >>>>> I am thinking if it's possible to share an basic tree which include >>>>> some >>>>> widely wanted backporting features. That could share the testing and >>>>> review, >>>>> then will reduce bugs much more. >>>> >>>> Like LTSI already does today? :) >>> >>> It looks we share some basic ideas on backporting part. But industry need >>> much more backporting features. and new features which out of upstream >>> aren't started from here, since it's a upstream quality without more eyes >>> in >>> community. >> >> I have no idea what you mean by this. Please give specific examples of >> what you have problems with. > > > The industry need much more features on LTS kernel for their product. > Like on linaro stable kernel 4.1, we backported PCIe of arm64, opp v2, > writeback cgroup... 11 features on that. All of them are come from arm, > hisilicon, QC, zte etc. > > And in fact, hosting new features which target on upstream kernel isn't a > good idea, since no much upstream guys like to look into this tree or do > testing on this tree. > > So looks like to share more backporting instead of upstream target feature > could fit more industry needs. Alex, I think Linaro's interpretation of a stable kernel is not very relevant for this discussion. arm64 support in the Linux kernel is not nearly as mature as support for the x86 architecture and other features and/or subsystems, and this is why we have the LSK, which consists of an otherwise stable kernel tree combined with more recent changes specific to the arm64 architecture and various SoCs and platforms that implement it. I think this discussion is more about regressions in production systems running stable kernels. -- Ard.