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 83C01C433F5 for ; Fri, 10 Dec 2021 07:16:38 +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-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:CC:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=4xEJBps3F8ARhevQgAlimRaJ4uEdbNip7OYB3SmQ74o=; b=zq5R0Q5g4+Jmec KF930brUDXNXQ4MaTz2DK/NBSHzNxHDmzQcA9CPJxzQOOPU6zbKINrqC5eZDNs3uiE5x4WJIt4s33 EFlypNMlQzYo/aoTY2va7URL/U4v19RUiLA9zDCSQ2fLRcffo9PsP0r+637+zj2GmtYwX2PsFAdW0 jMJ0VAJZNhI9lPC1T1jTTgLZ2FnKoJOjUkivWNrDgtqdaGTbFVFL+4KVWTA5S4iBEYCfkRS4QoMTG t0a7ZtsGgJG1uqIGklLofUvhY8lJC/R2SWKGQoFk4eypoIdTj+PLUK//4EpRaBy810IBErub3a6Jv YmQo6xuYngXxv3Kif4qA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mva7c-00128p-BR; Fri, 10 Dec 2021 07:15:12 +0000 Received: from szxga03-in.huawei.com ([45.249.212.189]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mva7W-00126V-GE; Fri, 10 Dec 2021 07:15:08 +0000 Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.54]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4J9MYf5c15z8vnk; Fri, 10 Dec 2021 15:12:54 +0800 (CST) Received: from dggpemm500001.china.huawei.com (7.185.36.107) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Fri, 10 Dec 2021 15:15:02 +0800 Received: from [10.174.177.243] (10.174.177.243) by dggpemm500001.china.huawei.com (7.185.36.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2308.20; Fri, 10 Dec 2021 15:15:01 +0800 Message-ID: Date: Fri, 10 Dec 2021 15:15:00 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [PATCH v17 00/10] support reserving crashkernel above 4G on arm64 kdump Content-Language: en-US To: Zhen Lei , Thomas Gleixner , Ingo Molnar , Borislav Petkov , , "H . Peter Anvin" , , Dave Young , Baoquan He , Vivek Goyal , Eric Biederman , , Catalin Marinas , Will Deacon , , Rob Herring , Frank Rowand , , "Jonathan Corbet" , CC: Randy Dunlap , Feng Zhou , Chen Zhou References: <20211210065533.2023-1-thunder.leizhen@huawei.com> From: Kefeng Wang In-Reply-To: <20211210065533.2023-1-thunder.leizhen@huawei.com> X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggeme710-chm.china.huawei.com (10.1.199.106) To dggpemm500001.china.huawei.com (7.185.36.107) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211209_231506_912063_B8D280E1 X-CRM114-Status: GOOD ( 18.05 ) 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-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2021/12/10 14:55, Zhen Lei wrote: > There are following issues in arm64 kdump: > 1. We use crashkernel=X to reserve crashkernel below 4G, which > will fail when there is no enough low memory. > 2. If reserving crashkernel above 4G, in this case, crash dump > kernel will boot failure because there is no low memory available > for allocation. > > To solve these issues, change the behavior of crashkernel=X. > crashkernel=X tries low allocation in DMA zone and fall back to high > allocation if it fails. > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > When reserving crashkernel in high memory, some low memory is reserved > for crash dump kernel devices. So there may be two regions reserved for > crash dump kernel. > In order to distinct from the high region and make no effect to the use > of existing kexec-tools, rename the low region as "Crash kernel (low)", > and pass the low region by reusing DT property > "linux,usable-memory-range". We made the low memory region as the last > range of "linux,usable-memory-range" to keep compatibility with existing > user-space and older kdump kernels. > > Besides, we need to modify kexec-tools: > arm64: support more than one crash kernel regions(see [1]) > > Another update is document about DT property 'linux,usable-memory-range': > schemas: update 'linux,usable-memory-range' node schema(see [2]) > > This patchset contains the following 10 patches: > > 0001-0004 are some x86 cleanups which prepares for making functionsreserve_crashkernel[_low]() generic. > 0005 makes functions reserve_crashkernel[_low]() generic. > 0006-0007 reimplements arm64 crashkernel=X. > 0008-0009 adds memory for devices by DT property linux,usable-memory-range. > 0010 updates the doc. > > Changes since [v16] > - Because no functional changes in this version, so add > "Tested-by: Dave Kleikamp " for patch 1-9 > - Add "Reviewed-by: Rob Herring " for patch 8 > - Update patch 9 based on the review comments of Rob Herring > - As Catalin Marinas's suggestion, merge the implementation of > ARCH_WANT_RESERVE_CRASH_KERNEL into patch 5. Ensure that the > contents of X86 and ARM64 do not overlap, and reduce unnecessary > temporary differences. An Internal review has been done, so for this series, Reviewed-by: Kefeng Wang _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel