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=-8.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 50118C388F2 for ; Tue, 3 Nov 2020 11:11:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFDDF223BD for ; Tue, 3 Nov 2020 11:11:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=axis.com header.i=@axis.com header.b="QFgfz7uD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728247AbgKCLLO (ORCPT ); Tue, 3 Nov 2020 06:11:14 -0500 Received: from smtp2.axis.com ([195.60.68.18]:33746 "EHLO smtp2.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725988AbgKCLLN (ORCPT ); Tue, 3 Nov 2020 06:11:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; l=1649; q=dns/txt; s=axis-central1; t=1604401873; x=1635937873; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=i5CSmu9+LpfEutwG2UOnvj25IvZpi4qmAuz9g3NC5Qc=; b=QFgfz7uDqIPpnMqxFKPA6erjXBfr1uzssxifgvYtz8DNI2XKx6WoTdeW MGVqyFBkAY/+D6iFstGAU2J0lIpfCgARwdz9Dghd3AZwbKwOWYVFEEeZ0 RTxFCkUwhKLHjEx/Fe3CspVKW9ijNL+JCWWZ2zvwLWVTyKEiD8G6KTJWj QAZPFkD37IClSzrh5xZ0j0w7IMZ3x4m7m3D0iyRkOsE2U1Sdp+NGl3ngM lgBPlqO5EiA9kyFcBXbDDSpaLY8NY4MRITwpkeooqI4JFLIlDASna8nHO zHbyGr4p9n7CV+quHK5qnrhJa/11rBw7ALRDgi/EGrcTf5v6jtKB9cwhR w==; IronPort-SDR: 1Zd6dDNif6MAndOHT4gj7Z10l+3bhqzM3EjvXKyX742M+LLPkrr5GQ14ax3hbHMxn+H1LA8MF3 SeetxIMiFXCYQbHhhCJa1CX3fRewO8MD4mjsuO36MTlRM1Z2h/1aQZ/bm4mlN1H0J6b2rx+7Az mi4KnKHoAl9Zax199xMetASEabUFcBYLl7wqcFOcOJIDecm2QOr4qYNvHE1sqTqDTEiILQ8TGf Ct2Sr8zTLaCglNSZ3vpnccNhQlIcXuaX5fH9onGy9LuF769bZFu5T+CDPaqRXsni8kJ2AIJyHE epY= X-IronPort-AV: E=Sophos;i="5.77,447,1596492000"; d="scan'208";a="14167250" Date: Tue, 3 Nov 2020 12:11:10 +0100 From: Vincent Whitchurch To: Sasha Levin CC: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Rob Herring , "devicetree@vger.kernel.org" Subject: Re: [PATCH AUTOSEL 4.4 3/5] of: Fix reserved-memory overlap detection Message-ID: <20201103111110.lvapcdf4nndunsie@axis.com> References: <20201103012119.184049-1-sashal@kernel.org> <20201103012119.184049-3-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20201103012119.184049-3-sashal@kernel.org> User-Agent: NeoMutt/20170113 (1.7.2) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 03, 2020 at 02:21:16AM +0100, Sasha Levin wrote: > From: Vincent Whitchurch > > [ Upstream commit ca05f33316559a04867295dd49f85aeedbfd6bfd ] > > The reserved-memory overlap detection code fails to detect overlaps if > either of the regions starts at address 0x0. The code explicitly checks > for and ignores such regions, apparently in order to ignore dynamically > allocated regions which have an address of 0x0 at this point. These > dynamically allocated regions also have a size of 0x0 at this point, so > fix this by removing the check and sorting the dynamically allocated > regions ahead of any static regions at address 0x0. > > For example, there are two overlaps in this case but they are not > currently reported: > > foo@0 { > reg = <0x0 0x2000>; > }; > > bar@0 { > reg = <0x0 0x1000>; > }; > > baz@1000 { > reg = <0x1000 0x1000>; > }; > > quux { > size = <0x1000>; > }; > > but they are after this patch: > > OF: reserved mem: OVERLAP DETECTED! > bar@0 (0x00000000--0x00001000) overlaps with foo@0 (0x00000000--0x00002000) > OF: reserved mem: OVERLAP DETECTED! > foo@0 (0x00000000--0x00002000) overlaps with baz@1000 (0x00001000--0x00002000) > > Signed-off-by: Vincent Whitchurch > Link: https://lore.kernel.org/r/ded6fd6b47b58741aabdcc6967f73eca6a3f311e.1603273666.git-series.vincent.whitchurch@axis.com > Signed-off-by: Rob Herring > Signed-off-by: Sasha Levin I'm not sure if this really needs to be backported. It's only fixing what is essentially a minor debugging feature.