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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 198F7C6FD20 for ; Fri, 24 Mar 2023 17:09:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=KEBCm34Wdd8VRZCkRntQsCYX5q1TK61XbCumPtcYF5w=; b=YDg/oJOdx185Kd zjvz/HoIuN8Ijz6r2cLtucEunom5f6yWY0e/clPPf7OetRmRYXIPAoEoAPDU/DqVrcuw17JNrbEGh hqBQq1gBb89+VOjGTWaqFScO30IvLwPAPCFWNNDiYOH2tNyX0ZQZmNawr5fkNtpAK2AfOsnCPEVVs 86tFxyUqdSuTGSASVtOjA0Y8Jn/80QHqrvFevhnDsS/jgresZ7GDdhooeq/fTgmhLRaJmtODCAjIv 6nD8ZHfmPpl0TLK8ciKKfoie1xrYojwC3TFtQDQrQpNimuizUkiQJ5J3HClNBpr1EXNTybDcukXor xV1/n4QMLbPwWShmfiOQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pfkuA-0053DQ-2f; Fri, 24 Mar 2023 17:08:42 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pfku7-0053CY-1N; Fri, 24 Mar 2023 17:08:40 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E206AB82565; Fri, 24 Mar 2023 17:08:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3361AC433D2; Fri, 24 Mar 2023 17:08:35 +0000 (UTC) Date: Fri, 24 Mar 2023 17:08:32 +0000 From: Catalin Marinas To: Baoquan He Cc: linux-kernel@vger.kernel.org, horms@kernel.org, thunder.leizhen@huawei.com, John.p.donnelly@oracle.com, will@kernel.org, kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4] arm64: kdump: simplify the reservation behaviour of crashkernel=,high Message-ID: References: <20230306084124.300584-1-bhe@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230324_100839_621117_BE46E6A7 X-CRM114-Status: GOOD ( 15.27 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Mar 24, 2023 at 10:08:17PM +0800, Baoquan He wrote: > On 03/23/23 at 05:25pm, Catalin Marinas wrote: > > On Mon, Mar 20, 2023 at 09:12:08PM +0800, Baoquan He wrote: > > > crashkernel=size > > > 1)first attempt: low memory under arm64_dma_phys_limit > > > 2)fallback: finding memory above 4G > > > > (2) should be 'finding memory above arm64_dma_phys_limit' to keep the > > current behaviour for RPi4. > > Then for RPi4, with case 2), it will find memory above > arm64_dma_phys_limit, namely 1G. Then it will get two memory regions, > one could be in [1G, 4G], another is below 4G. I am fine with this, as > long as it won't cause confusion that people may think two low memory > regions you mentioned earlier. Please help confirm if I understand your > suggestioin correctly. I will start making patch with this clarified. Yes, you understood correctly. While it may still be slightly confusing, if the user is not specific about high and low on the cmdline, we just allow the kernel to find the best places. I assume distros will just use ,high and get a consistent behaviour on all platforms. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel