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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 BA816C4360F for ; Wed, 3 Apr 2019 02:54:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94C6B20830 for ; Wed, 3 Apr 2019 02:54:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727020AbfDCCyo (ORCPT ); Tue, 2 Apr 2019 22:54:44 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:5654 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726425AbfDCCyo (ORCPT ); Tue, 2 Apr 2019 22:54:44 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [10.3.19.208]) by Forcepoint Email with ESMTP id 0B3E5907F4EA0FB37403; Wed, 3 Apr 2019 10:54:42 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.408.0; Wed, 3 Apr 2019 10:54:32 +0800 From: Chen Zhou To: , , , , , CC: , , , , , Chen Zhou Subject: [PATCH 1/3] arm64: kdump: support reserving crashkernel above 4G Date: Wed, 3 Apr 2019 11:05:44 +0800 Message-ID: <20190403030546.23718-2-chenzhou10@huawei.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190403030546.23718-1-chenzhou10@huawei.com> References: <20190403030546.23718-1-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] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When crashkernel is reserved above 4G in memory, kernel should reserve some amount of low memory for swiotlb and some DMA buffers. Kernel would try to allocate at least 256M below 4G automatically as x86_64 if crashkernel is above 4G. Meanwhile, support crashkernel=X,[high,low] in arm64. Signed-off-by: Chen Zhou --- arch/arm64/kernel/setup.c | 3 ++ arch/arm64/mm/init.c | 71 +++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 71 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 413d566..82cd9a0 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -243,6 +243,9 @@ static void __init request_standard_resources(void) request_resource(res, &kernel_data); #ifdef CONFIG_KEXEC_CORE /* Userspace will find "Crash kernel" region in /proc/iomem. */ + 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 6bc1350..ceb2a25 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -64,6 +64,57 @@ EXPORT_SYMBOL(memstart_addr); phys_addr_t arm64_dma_phys_limit __ro_after_init; #ifdef CONFIG_KEXEC_CORE +static int __init reserve_crashkernel_low(void) +{ + unsigned long long base, low_base = 0, low_size = 0; + unsigned long total_low_mem; + int ret; + + total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT)); + + /* crashkernel=Y,low */ + ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base); + if (ret) { + /* + * two parts from lib/swiotlb.c: + * -swiotlb size: user-specified with swiotlb= or default. + * + * -swiotlb overflow buffer: now hardcoded to 32k. We round it + * to 8M for other buffers that may need to stay low too. Also + * make sure we allocate enough extra low memory so that we + * don't run out of DMA buffers for 32-bit devices. + */ + low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); + } else { + /* passed with crashkernel=0,low ? */ + if (!low_size) + return 0; + } + + low_base = memblock_find_in_range(0, 1ULL << 32, low_size, SZ_2M); + if (!low_base) { + pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", + (unsigned long)(low_size >> 20)); + return -ENOMEM; + } + + ret = memblock_reserve(low_base, low_size); + if (ret) { + pr_err("%s: Error reserving crashkernel low memblock.\n", __func__); + return ret; + } + + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System RAM: %ldMB)\n", + (unsigned long)(low_size >> 20), + (unsigned long)(low_base >> 20), + (unsigned long)(total_low_mem >> 20)); + + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; + + return 0; +} + /* * reserve_crashkernel() - reserves memory for crash kernel * @@ -74,19 +125,28 @@ phys_addr_t arm64_dma_phys_limit __ro_after_init; static void __init reserve_crashkernel(void) { unsigned long long crash_base, crash_size; + bool high = false; int ret; ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), &crash_size, &crash_base); /* no crashkernel= or invalid value specified */ - if (ret || !crash_size) - return; + if (ret || !crash_size) { + /* crashkernel=X,high */ + ret = parse_crashkernel_high(boot_command_line, memblock_phys_mem_size(), + &crash_size, &crash_base); + if (ret || !crash_size) + return; + high = true; + } 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_base = memblock_find_in_range(0, + high ? memblock_end_of_DRAM() + : ARCH_LOW_ADDRESS_LIMIT, crash_size, SZ_2M); if (crash_base == 0) { pr_warn("cannot allocate crashkernel (size:0x%llx)\n", @@ -112,6 +172,11 @@ static void __init reserve_crashkernel(void) } memblock_reserve(crash_base, crash_size); + if (crash_base >= SZ_4G && reserve_crashkernel_low()) { + memblock_free(crash_base, crash_size); + return; + } + pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", crash_base, crash_base + crash_size, crash_size >> 20); -- 2.7.4