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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no 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 81AE0C2D0D0 for ; Mon, 23 Dec 2019 15:27:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 620F020709 for ; Mon, 23 Dec 2019 15:27:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726928AbfLWP1X (ORCPT ); Mon, 23 Dec 2019 10:27:23 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:8165 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726795AbfLWP1W (ORCPT ); Mon, 23 Dec 2019 10:27:22 -0500 Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id D2057C95DE330A81C437; Mon, 23 Dec 2019 23:27:19 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.439.0; Mon, 23 Dec 2019 23:27:11 +0800 From: Chen Zhou To: , , , , , , CC: , , , , , , Subject: [PATCH v7 0/4] support reserving crashkernel above 4G on arm64 kdump Date: Mon, 23 Dec 2019 23:23:45 +0800 Message-ID: <20191223152349.180172-1-chenzhou10@huawei.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.113.25] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch series enable reserving crashkernel above 4G in arm64. 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. Currently, crashkernel=Y@X can be used to reserve crashkernel above 4G, in this case, if swiotlb or DMA buffers are required, crash dump kernel will boot failure because there is no low memory available for allocation. To solve these issues, introduce crashkernel=X,low to reserve specified size low memory. Crashkernel=X tries to reserve memory for the crash dump kernel under 4G. If crashkernel=Y,low is specified simultaneously, reserve spcified size low memory for crash kdump kernel devices firstly and then reserve memory above 4G. When crashkernel is reserved above 4G in memory, that is, crashkernel=X,low is specified simultaneously, kernel should reserve specified size low memory for crash dump kernel devices. So there may be two crash kernel regions, one is below 4G, the other is above 4G. In order to distinct from the high region and make no effect to the use of kexec-tools, rename the low region as "Crash kernel (low)", and add DT property "linux,low-memory-range" to crash dump kernel's dtb to pass the low region. Besides, we need to modify kexec-tools: arm64: kdump: add another DT property to crash dump kernel's dtb(see [1]) The previous changes and discussions can be retrieved from: Changes since [v6] - Fix build errors reported by kbuild test robot. Changes since [v5] - Move reserve_crashkernel_low() into kernel/crash_core.c. - Delete crashkernel=X,high. - Modify crashkernel=X,low. If crashkernel=X,low is specified simultaneously, reserve spcified size low memory for crash kdump kernel devices firstly and then reserve memory above 4G. In addition, rename crashk_low_res as "Crash kernel (low)" for arm64, and then pass to crash dump kernel by DT property "linux,low-memory-range". - Update Documentation/admin-guide/kdump/kdump.rst. Changes since [v4] - Reimplement memblock_cap_memory_ranges for multiple ranges by Mike. Changes since [v3] - Add memblock_cap_memory_ranges back for multiple ranges. - Fix some compiling warnings. Changes since [v2] - Split patch "arm64: kdump: support reserving crashkernel above 4G" as two. Put "move reserve_crashkernel_low() into kexec_core.c" in a separate patch. Changes since [v1]: - Move common reserve_crashkernel_low() code into kernel/kexec_core.c. - Remove memblock_cap_memory_ranges() i added in v1 and implement that in fdt_enforce_memory_region(). There are at most two crash kernel regions, for two crash kernel regions case, we cap the memory range [min(regs[*].start), max(regs[*].end)] and then remove the memory range in the middle. [1]: http://lists.infradead.org/pipermail/kexec/2019-August/023569.html [v1]: https://lkml.org/lkml/2019/4/2/1174 [v2]: https://lkml.org/lkml/2019/4/9/86 [v3]: https://lkml.org/lkml/2019/4/9/306 [v4]: https://lkml.org/lkml/2019/4/15/273 [v5]: https://lkml.org/lkml/2019/5/6/1360 [v6]: https://lkml.org/lkml/2019/8/30/142 Chen Zhou (4): x86: kdump: move reserve_crashkernel_low() into crash_core.c arm64: kdump: reserve crashkenel above 4G for crash dump kernel arm64: kdump: add memory for devices by DT property, low-memory-range kdump: update Documentation about crashkernel on arm64 Documentation/admin-guide/kdump/kdump.rst | 13 +++- Documentation/admin-guide/kernel-parameters.txt | 12 +++- arch/arm64/kernel/setup.c | 8 ++- arch/arm64/mm/init.c | 61 ++++++++++++++++- arch/x86/kernel/setup.c | 62 ++---------------- include/linux/crash_core.h | 3 + include/linux/kexec.h | 2 - kernel/crash_core.c | 87 +++++++++++++++++++++++++ kernel/kexec_core.c | 17 ----- 9 files changed, 183 insertions(+), 82 deletions(-) -- 2.7.4