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=-2.3 required=3.0 tests=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 8C1BCC43382 for ; Tue, 25 Sep 2018 08:58:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3AE0920867 for ; Tue, 25 Sep 2018 08:58:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3AE0920867 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.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 S1728636AbeIYPFX (ORCPT ); Tue, 25 Sep 2018 11:05:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58166 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726660AbeIYPFW (ORCPT ); Tue, 25 Sep 2018 11:05:22 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 10AE830842D0; Tue, 25 Sep 2018 08:58:52 +0000 (UTC) Received: from localhost (ovpn-8-17.pek2.redhat.com [10.72.8.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6EFBB1001914; Tue, 25 Sep 2018 08:58:49 +0000 (UTC) Date: Tue, 25 Sep 2018 16:58:46 +0800 From: Baoquan He To: Bjorn Helgaas Cc: Lianbo Jiang , Vivek Goyal , linux-kernel@vger.kernel.org, kexec@lists.infradead.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, akpm@linux-foundation.org, dan.j.williams@intel.com, thomas.lendacky@amd.com, baiyaowei@cmss.chinamobile.com, tiwai@suse.de, bp@suse.de, brijesh.singh@amd.com, dyoung@redhat.com Subject: Re: [PATCH 3/3] resource: Fix find_next_iomem_res() iteration issue Message-ID: <20180925085846.GY2555@MiWiFi-R3L-srv> References: <153782698067.130337.12079523922130875402.stgit@bhelgaas-glaptop.roam.corp.google.com> <153782730364.130337.17794279728329113665.stgit@bhelgaas-glaptop.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <153782730364.130337.17794279728329113665.stgit@bhelgaas-glaptop.roam.corp.google.com> User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Tue, 25 Sep 2018 08:58:52 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Bjorn, On 09/24/18 at 05:15pm, Bjorn Helgaas wrote: > @@ -359,32 +362,31 @@ static int find_next_iomem_res(struct resource *res, unsigned long desc, > read_unlock(&resource_lock); > if (!p) > return -1; > + > /* copy data */ > - if (res->start < p->start) > - res->start = p->start; > - if (res->end > p->end) > - res->end = p->end; > + res->start = max(start, p->start); > + res->end = min(end, p->end); > res->flags = p->flags; I think this fix is good. However, is it OK to keep res->flags always, never touch it in find_next_iomem_res()? We just iterate and update region, its start and end. So just removing that "res->flags = p->flags;" line might involve much less code changes. Thanks Baoquan From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1g4jBj-0000k1-6j for kexec@lists.infradead.org; Tue, 25 Sep 2018 08:59:24 +0000 Date: Tue, 25 Sep 2018 16:58:46 +0800 From: Baoquan He Subject: Re: [PATCH 3/3] resource: Fix find_next_iomem_res() iteration issue Message-ID: <20180925085846.GY2555@MiWiFi-R3L-srv> References: <153782698067.130337.12079523922130875402.stgit@bhelgaas-glaptop.roam.corp.google.com> <153782730364.130337.17794279728329113665.stgit@bhelgaas-glaptop.roam.corp.google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <153782730364.130337.17794279728329113665.stgit@bhelgaas-glaptop.roam.corp.google.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Bjorn Helgaas Cc: dan.j.williams@intel.com, brijesh.singh@amd.com, Lianbo Jiang , thomas.lendacky@amd.com, tiwai@suse.de, x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, baiyaowei@cmss.chinamobile.com, hpa@zytor.com, tglx@linutronix.de, bp@suse.de, dyoung@redhat.com, akpm@linux-foundation.org, Vivek Goyal Hi Bjorn, On 09/24/18 at 05:15pm, Bjorn Helgaas wrote: > @@ -359,32 +362,31 @@ static int find_next_iomem_res(struct resource *res, unsigned long desc, > read_unlock(&resource_lock); > if (!p) > return -1; > + > /* copy data */ > - if (res->start < p->start) > - res->start = p->start; > - if (res->end > p->end) > - res->end = p->end; > + res->start = max(start, p->start); > + res->end = min(end, p->end); > res->flags = p->flags; I think this fix is good. However, is it OK to keep res->flags always, never touch it in find_next_iomem_res()? We just iterate and update region, its start and end. So just removing that "res->flags = p->flags;" line might involve much less code changes. Thanks Baoquan _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec