From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41673C433FF for ; Thu, 1 Aug 2019 07:41:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11B9620838 for ; Thu, 1 Aug 2019 07:41:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="FIzQTHdY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729266AbfHAHle (ORCPT ); Thu, 1 Aug 2019 03:41:34 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:46831 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729140AbfHAHle (ORCPT ); Thu, 1 Aug 2019 03:41:34 -0400 Received: by mail-pg1-f194.google.com with SMTP id k189so14620940pgk.13 for ; Thu, 01 Aug 2019 00:41:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=stRY7i1GZrfY6D+PTgs0D4UrvfUCsK1idtnpqO9v05A=; b=FIzQTHdYyzbSF4UXVeIZHy3ZAwIm6WNjJ/7SFU/GqKhukmbYUPc5uoLrynWLyUBJVb fRHC5adeqiJFVkCnJcahOseTMZ7e2ZkBrgl6yzcXksAwGWJhQu+I8pPcCuRU+gQJMZrt 6zWlCDe679nJhA/Frtiufn5nm9bM8CDM32JZOhtmzzcvNFyU0tW2INMvtpZKKuJlNGB1 Z05sWFHKHngzHjtuXq+dCNMtQE/y0N5oT7ENpWnZjy2HUF3NgPHY0YsXwrYwcAhAhbfK BwVZloDwEUKpWfOLiuawIFKfuHlNJKEVWD08Fy5DVw55YcQkMA1MTyaNgn+YACVYM24+ I9QA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=stRY7i1GZrfY6D+PTgs0D4UrvfUCsK1idtnpqO9v05A=; b=dCf0pcyIQfrPlPm6vCy9hG2d/fP00ks2/ShVnJzRLUtmNZL0hA359Auw+OVQgZj6W5 gOZI1I25qrCLE/OsbNhbNxkdCX64hAuaBWvSp1bo2PGx/clLBYguFlEu046mEa1Ai6Kk zT9kabZgb2VevWAo/1+K7afc9f2Nw5oi6jDBJbDrOyZQWGHmjnjj8SAHD0w+9O104V/c iH+DEU0qQOi1+3plsNBx3hu+9MA4WtZLiWq+ui4GdM/2ISzxFp414oozVMelopC4iyqQ kGHCl+t7hJo5JxtMSukYAa5joO/AQVvxBhDEBXzmRGLRah9HB1BaRnDyiL+A7Hma/S67 9/OQ== X-Gm-Message-State: APjAAAX8NLPmp8gGctfzex9aQia52SJvxpt7Z1oG61W8LBy9DTUPyjNC vAIdX6jUzPgq7hzNROrz0VRbaQ== X-Google-Smtp-Source: APXvYqyjrB9ZTQXX8An99agwlE3etMrgkqcBgU4z6N9t7CiNe210eVe0fuU/nEZOBJMkJFfzCzTgfw== X-Received: by 2002:a17:90a:228b:: with SMTP id s11mr6888100pjc.23.1564645293756; Thu, 01 Aug 2019 00:41:33 -0700 (PDT) Received: from localhost ([122.172.28.117]) by smtp.gmail.com with ESMTPSA id u97sm4101405pjb.26.2019.08.01.00.41.32 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 01 Aug 2019 00:41:32 -0700 (PDT) Date: Thu, 1 Aug 2019 13:11:31 +0530 From: Viresh Kumar To: Will Deacon Cc: Greg KH , Mark Rutland , Julien Thierry , Marc Zyngier , Catalin Marinas , Will Deacon , stable@vger.kernel.org, mark.brown@arm.com, julien.thierry.kdev@gmail.com, Russell King , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4.4 V2 25/43] arm64: Move BP hardening to check_and_switch_context Message-ID: <20190801074131.526h5d4hwpxutlq2@vireshk-i7> References: <59b252cf-9cb7-128b-4887-c21a8b9b92a9@arm.com> <20190801050940.h65crfawrdifsrgg@vireshk-i7> <86354576-fc54-a8b7-4dc9-bc613d59fb17@arm.com> <20190801063544.ruw444isj5uojjdx@vireshk-i7> <20190801065700.GA17391@kroah.com> <20190801070541.hpmadulgp45txfem@vireshk-i7> <20190801073444.4n45h6kcbmejvzte@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190801073444.4n45h6kcbmejvzte@willie-the-truck> User-Agent: NeoMutt/20180716-391-311a52 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 01-08-19, 08:34, Will Deacon wrote: > On Thu, Aug 01, 2019 at 12:35:41PM +0530, Viresh Kumar wrote: > > On 01-08-19, 08:57, Greg KH wrote: > > > On Thu, Aug 01, 2019 at 12:05:44PM +0530, Viresh Kumar wrote: > > > > On 01-08-19, 07:30, Julien Thierry wrote: > > > > > I must admit I am not familiar with backport/stable process enough. But > > > > > personally I think the your suggestion seems more sensible than > > > > > backporting 4 patches. > > > > > > > > > > Or you can maybe ignore patch 25 and say in patch 24 that among the > > > > > changes made for the 4.4 codebase, the call arm64_apply_bp_hardening() > > > > > was moved from post_ttbr_update_workaround as it doesn't exist and > > > > > placed in check_and_switch_context() as it is its final destination. > > > > > > > > Done that and dropped the other two patches. > > > > > > > > > However, I really don't know what's the best way to proceed according to > > > > > existing practices. So input from someone else would be welcome. > > > > > > > > Lets see if someone comes up and ask me to do something else :) > > > > > > Keeping the same patches that upstream has is almost always the better > > > thing to do in the long-run. > > > > That would require two additional patches to be backported, 22 and 23 > > from this series. From your suggestion it seems that keeping them is > > better here ? > > Yes. Backporting individual patches as they appear upstream is definitely > the preferred method for -stable. It makes the relationship to mainline > crystal clear, as well as any dependencies between patches that have been > backported. Everytime we tweak something unecessarily in a stable backport, > it just creates the potential for confusion and additional conflicts in > future backports, so it's best to follow the shape of upstream as closely as > possible, even if it results in additional patches. > > So I wouldn't worry about total number of patches. I'd worry more about > things like conflicts, deviation from mainline and overall testing coverage. Okay, I won't make these changes then. Thanks. -- viresh