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 15BFBC433FF for ; Thu, 1 Aug 2019 08:44:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DBD89206A3 for ; Thu, 1 Aug 2019 08:44:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kroah.com header.i=@kroah.com header.b="JJwGdkRI"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="hcxj3NJM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729021AbfHAIoB (ORCPT ); Thu, 1 Aug 2019 04:44:01 -0400 Received: from new4-smtp.messagingengine.com ([66.111.4.230]:53939 "EHLO new4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728922AbfHAIoB (ORCPT ); Thu, 1 Aug 2019 04:44:01 -0400 Received: from compute6.internal (compute6.nyi.internal [10.202.2.46]) by mailnew.nyi.internal (Postfix) with ESMTP id 4A0D12B22; Thu, 1 Aug 2019 04:44:00 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute6.internal (MEProxy); Thu, 01 Aug 2019 04:44:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm1; bh=6WafO7cI6r8VaJJsdXC/ys704rY XUFHR38NTVXOrVBI=; b=JJwGdkRI9foxSc48bXUp94Bx81Ro7lRFO9/F/+73h10 gUO01O36cL23W8Vqv/IbKQ2vxscypeeUpyQMgZnRvqHBHteUSvaQE+DuRDI5rQro 0cNmuvsDDCjySzqVgmP0B+kPxf+IeH7TTWg70h3KIwV1aob0yU9WiK8Kt2jQ2dfq gCfUYevOeA+xPkOLY9WA/Aw/tRLY2PbwYeZ2ywfwi4NOPpxBvKf5LYAZn7u+d+kS OXOcUWCT1jY9oxkZEQIPDRTrxFlW6vuX0SDuCIW+rD1ky6ojcsQr3JNX9fG2T22o b/4z0cCV+OWPkbab0sJYgXwvDyrFuukPm/6UntcXjng== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=6WafO7 cI6r8VaJJsdXC/ys704rYXUFHR38NTVXOrVBI=; b=hcxj3NJM2t2lvrpzzqmqhm rhDP/nC3yP7CZv4ZSMp8b/KYE/XULqB4Xo7o1+u3UNE81tqyRRQDYjF5aDBINKoJ D7RkmgONAZ9EJ+tM9Klz20nfIjr+jwwZ1kVNKxRuYUekkRaSM/YGzU+N3TubUy/R BJqupysIFdohrrhUe1HBioqMb5rewfEdqpqh6JuUZOKAgJc6lZ45xJiVaJjs+Pwz N+kadhJDfbVKV2KRh0qLvR+3Wd4cBb6NSC6D8p5leWJDu44y6Y+7zSCSGzb/Mw9s Q+4pX555L30fHgwPt+/SkmfrsdNHqGwsCMtAlzwg+5z3C4YxWYcX3DGD8zyO9IDQ == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduvddrleejgddtiecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujggfsehttdertddtredvnecuhfhrohhmpefirhgvghcu mffjuceoghhrvghgsehkrhhorghhrdgtohhmqeenucfkphepvddufedruddvjedrvdehud drvdduieenucfrrghrrghmpehmrghilhhfrhhomhepghhrvghgsehkrhhorghhrdgtohhm necuvehluhhsthgvrhfuihiivgeptd X-ME-Proxy: Received: from localhost (ip-213-127-251-216.ip.prioritytelecom.net [213.127.251.216]) by mail.messagingengine.com (Postfix) with ESMTPA id 922928005A; Thu, 1 Aug 2019 04:43:58 -0400 (EDT) Date: Thu, 1 Aug 2019 10:43:54 +0200 From: Greg KH To: Will Deacon Cc: Viresh Kumar , 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: <20190801084354.GA1085@kroah.com> 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: Mutt/1.12.1 (2019-06-15) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Thu, Aug 01, 2019 at 08:34:45AM +0100, 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. That is exactly correct, thanks for saying it better than I could :) greg k-h