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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 15094C3A5A3 for ; Fri, 30 Aug 2019 07:09:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E418C22CE3 for ; Fri, 30 Aug 2019 07:09:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728152AbfH3HJE (ORCPT ); Fri, 30 Aug 2019 03:09:04 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:39958 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727963AbfH3HJC (ORCPT ); Fri, 30 Aug 2019 03:09:02 -0400 Received: from DGGEMS401-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 2998F6AC2362E99A6B72; Fri, 30 Aug 2019 15:09:01 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by DGGEMS401-HUB.china.huawei.com (10.3.19.201) with Microsoft SMTP Server id 14.3.439.0; Fri, 30 Aug 2019 15:08:51 +0800 From: Chen Zhou To: , , , , , , CC: , , , , , Chen Zhou Subject: [PATCH v6 2/4] arm64: kdump: reserve crashkenel above 4G for crash dump kernel Date: Fri, 30 Aug 2019 15:11:58 +0800 Message-ID: <20190830071200.56169-3-chenzhou10@huawei.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190830071200.56169-1-chenzhou10@huawei.com> References: <20190830071200.56169-1-chenzhou10@huawei.com> 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 Crashkernel=X tries to reserve memory for the crash dump kernel under 4G. If crashkernel=X,low is specified simultaneously, reserve spcified size low memory for crash kdump kernel devices firstly and then reserve memory above 4G. Signed-off-by: Chen Zhou --- arch/arm64/include/asm/kexec.h | 3 +++ arch/arm64/kernel/setup.c | 8 +++++++- arch/arm64/mm/init.c | 31 +++++++++++++++++++++++++++++-- 3 files changed, 39 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index 12a561a..88279a9 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -25,6 +25,9 @@ #define KEXEC_ARCH KEXEC_ARCH_AARCH64 +/* 2M alignment for crash kernel regions */ +#define CRASH_ALIGN SZ_2M + #ifndef __ASSEMBLY__ /** diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 9c4bad7..2ead608 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -231,7 +231,13 @@ static void __init request_standard_resources(void) kernel_data.end <= res->end) request_resource(res, &kernel_data); #ifdef CONFIG_KEXEC_CORE - /* Userspace will find "Crash kernel" region in /proc/iomem. */ + /* + * Userspace will find "Crash kernel" region in /proc/iomem. + * Note: the low region is renamed as Crash kernel (low). + */ + if (crashk_low_res.end && crashk_low_res.start >= res->start && + crashk_low_res.end <= res->end) + request_resource(res, &crashk_low_res); if (crashk_res.end && crashk_res.start >= res->start && crashk_res.end <= res->end) request_resource(res, &crashk_res); diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index f3c7952..c99f845 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -64,6 +64,7 @@ static void __init reserve_crashkernel(void) { unsigned long long crash_base, crash_size; int ret; + phys_addr_t crash_max = ARCH_LOW_ADDRESS_LIMIT; ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), &crash_size, &crash_base); @@ -71,12 +72,38 @@ static void __init reserve_crashkernel(void) if (ret || !crash_size) return; + ret = reserve_crashkernel_low(); + if (!ret && crashk_low_res.end) { + /* + * If crashkernel=X,low specified, there may be two regions, + * we need to make some changes as follows: + * + * 1. rename the low region as "Crash kernel (low)" + * 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)". + * + * 2. change the upper bound for crash memory + * Set MEMBLOCK_ALLOC_ACCESSIBLE upper bound for crash memory. + * + * 3. mark the low region as "nomap" + * The low region is intended to be used for crash dump kernel + * devices, just mark the low region as "nomap" simply. + */ + const char *rename = "Crash kernel (low)"; + + crashk_low_res.name = rename; + crash_max = MEMBLOCK_ALLOC_ACCESSIBLE; + memblock_mark_nomap(crashk_low_res.start, + resource_size(&crashk_low_res)); + } + crash_size = PAGE_ALIGN(crash_size); if (crash_base == 0) { /* Current arm64 boot protocol requires 2MB alignment */ - crash_base = memblock_find_in_range(0, ARCH_LOW_ADDRESS_LIMIT, - crash_size, SZ_2M); + crash_base = memblock_find_in_range(0, crash_max, crash_size, + SZ_2M); if (crash_base == 0) { pr_warn("cannot allocate crashkernel (size:0x%llx)\n", crash_size); -- 2.7.4