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_PASS, USER_AGENT_MUTT autolearn=ham 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 E4383C04ABB for ; Thu, 13 Sep 2018 12:19:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C2AD20882 for ; Thu, 13 Sep 2018 12:19:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kroah.com header.i=@kroah.com header.b="VDSJajtj"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="fPiKBIXE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C2AD20882 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kroah.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728024AbeIMR3H (ORCPT ); Thu, 13 Sep 2018 13:29:07 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:33829 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727007AbeIMR3H (ORCPT ); Thu, 13 Sep 2018 13:29:07 -0400 Received: from compute6.internal (compute6.nyi.internal [10.202.2.46]) by mailout.nyi.internal (Postfix) with ESMTP id 22C9421F23; Thu, 13 Sep 2018 08:19:53 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute6.internal (MEProxy); Thu, 13 Sep 2018 08:19:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=N1vRXIfx5xBcMNQSxmKp7q3aIrXLEe95WD5P7vEuMGc=; b=VDSJajtj RNsxJ+HZD8PzEOhlqHwGTe3K9pvlNq/A0QfhVz2rkkGjGPVUnfxMPcSAc6/+s3mZ xQu5BO4g7mSz8Smm95NPxA/Pkf0SHjS1nd8MEDPyP7U7H0RUeCVRfbihFovNS/jg ZXS+/W0Yd8HLmf8EdEUv+KC8XGPJY730NjwBx079698G3l8J8lfcYOA3pE37Q5Kj ziyCjWvEEQIlSFpsFsVzHRuadMkG4nK73JswUUzZJ48mUXH8h5ktVlssRLA6Kg81 UxDsWBjyFxbCAuKaJvzhAISRJA3nCVaQ7uxOOHwyUoxMxnXsb3vQrVsjA5bdoi/F II3qjcj8sgYfqg== 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-sender :x-me-sender:x-sasl-enc; s=fm3; bh=N1vRXIfx5xBcMNQSxmKp7q3aIrXLE e95WD5P7vEuMGc=; b=fPiKBIXEk/796/k5ppB9k33TeAGv4CgXybJEy1B52rTwK OfvrHg3iP6RFo46kTJuBXTodh6Buaq1+dCIFvd2XimL8hG4dUJEJId2P4BF8IT27 Goz0ktjECA3zfR2l/d1lpnFwRHbZ1opHeIjJZLcnJp36kpF4xPQM4i5N2oGRa8ic 4PWE34sR9lBcfJ/FdZjqPXbBfLvQ/LAh+mBR0b0LO5wIBqTodZZW8yWlXspDGoFg iPd646eooKE/eQhJ9sp9lL36ddjwfVqExy6sXgu5kFWW/I1cpJ0OUo4l4dU4DUDn fxdcyesA5m9myZLgSvaZesYZrklckajuxXFGLU+bw== X-ME-Proxy: X-ME-Sender: Received: from localhost (ip-213-127-77-73.ip.prioritytelecom.net [213.127.77.73]) by mail.messagingengine.com (Postfix) with ESMTPA id 401C0102D6; Thu, 13 Sep 2018 08:19:52 -0400 (EDT) Date: Thu, 13 Sep 2018 14:19:51 +0200 From: Greg KH To: Suzuki K Poulose Cc: stable@vger.kernel.org, will.deacon@arm.com, mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, catalin.marinas@arm.com Subject: Re: [stable PATCH 1/2] arm64: Fix mismatched cache line size detection Message-ID: <20180913121951.GE2268@kroah.com> References: <1536052210-11625-1-git-send-email-suzuki.poulose@arm.com> <20180912193816.GF21563@kroah.com> <4b8db4d5-20d7-5597-7977-b8df1072ecc7@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4b8db4d5-20d7-5597-7977-b8df1072ecc7@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 13, 2018 at 10:54:06AM +0100, Suzuki K Poulose wrote: > Hi Greg, > > On 12/09/18 20:38, Greg KH wrote: > > On Tue, Sep 04, 2018 at 10:10:09AM +0100, Suzuki K Poulose wrote: > > > commit 4c4a39dd5fe2d13e2d2fa5fceb8ef95d19fc389a upstream > > > > > > If there is a mismatch in the I/D min line size, we must > > > always use the system wide safe value both in applications > > > and in the kernel, while performing cache operations. However, > > > we have been checking more bits than just the min line sizes, > > > which triggers false negatives. We may need to trap the user > > > accesses in such cases, but not necessarily patch the kernel. > > > > > > This patch fixes the check to do the right thing as advertised. > > > A new capability will be added to check mismatches in other > > > fields and ensure we trap the CTR accesses. > > > > > > Fixes: be68a8aaf925 ("arm64: cpufeature: Fix CTR_EL0 field definitions") > > > Cc: # v4.9 > > > > Why 4.9? be68a8aaf925 only showed up in 4.16 and was backported only to > > 4.14-stable. Not to 4.9-stable from what I can tell. > > Now when you asked this, I realise that the Fixes tags were not sufficient. > > Actually this series fixes a bit more than the commit: be68a8aaf925 ("arm64: cpufeature: > Fix CTR_EL0 field definitions"). I think these patches should have : > > Fixes: commit 116c81f427ff6c5 ("arm64: Work around systems with mismatched cache line sizes") > > and > > Enable trapping on mismatched bits in CTR for IDC/DIC, which were > added to v8.3 onwards. > > Essentially these patches makes sure that we trap accesses to > CTR_EL0 when some of the fields are mismatched across CPUs, so > that the CPUs get a consistent view of the cache properties > throughout the system. It also makes sure that we put out > correct information about why we trap accesses to the CTR_EL0 > accesses from the userspace. > > Hope this helps. The same applies for the next patch. Yes, it does help. But these patches do not apply to the 4.14.y series, which I also need to apply them to (you don't want to move from 4.9.y to 4.14.y and get a regression.) So can you provide backports for both of these patches for 4.14.y? Then I would be glad to queue these all up. thanks, greg k-h