From patchwork Sun Feb 27 03:07:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhen Lei X-Patchwork-Id: 546858 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD822C4332F for ; Sun, 27 Feb 2022 03:07:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229763AbiB0DI2 (ORCPT ); Sat, 26 Feb 2022 22:08:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229746AbiB0DI1 (ORCPT ); Sat, 26 Feb 2022 22:08:27 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 10A9720645C; Sat, 26 Feb 2022 19:07:48 -0800 (PST) Received: from dggpemm500020.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4K5pH26tY4z1FD3D; Sun, 27 Feb 2022 11:03:10 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500020.china.huawei.com (7.185.36.49) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:46 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:45 +0800 From: Zhen Lei To: 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: Zhen Lei , Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou , "John Donnelly" , Dave Kleikamp Subject: [PATCH v21 1/5] kdump: return -ENOENT if required cmdline option does not exist Date: Sun, 27 Feb 2022 11:07:13 +0800 Message-ID: <20220227030717.1464-2-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20220227030717.1464-1-thunder.leizhen@huawei.com> References: <20220227030717.1464-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The crashkernel=Y,low is an optional command-line option. When it doesn't exist, kernel will try to allocate minimum required memory below 4G automatically. Give it a unique error code to distinguish it from other error scenarios. Signed-off-by: Zhen Lei --- kernel/crash_core.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 256cf6db573cd09..4d57c03714f4e13 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -243,9 +243,8 @@ static int __init __parse_crashkernel(char *cmdline, *crash_base = 0; ck_cmdline = get_last_crashkernel(cmdline, name, suffix); - if (!ck_cmdline) - return -EINVAL; + return -ENOENT; ck_cmdline += strlen(name); From patchwork Sun Feb 27 03:07:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhen Lei X-Patchwork-Id: 546510 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1DD9DC4321E for ; Sun, 27 Feb 2022 03:07:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229773AbiB0DI2 (ORCPT ); Sat, 26 Feb 2022 22:08:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59880 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229747AbiB0DI1 (ORCPT ); Sat, 26 Feb 2022 22:08:27 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C11320645F; Sat, 26 Feb 2022 19:07:49 -0800 (PST) Received: from dggpemm500022.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4K5pLx0ksPzdZZq; Sun, 27 Feb 2022 11:06:33 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500022.china.huawei.com (7.185.36.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:47 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:46 +0800 From: Zhen Lei To: 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: Zhen Lei , Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou , "John Donnelly" , Dave Kleikamp Subject: [PATCH v21 2/5] arm64: Use insert_resource() to simplify code Date: Sun, 27 Feb 2022 11:07:14 +0800 Message-ID: <20220227030717.1464-3-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20220227030717.1464-1-thunder.leizhen@huawei.com> References: <20220227030717.1464-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org insert_resource() traverses the subtree layer by layer from the root node until a proper location is found. Compared with request_resource(), the parent node does not need to be determined in advance. In addition, move the insertion of node 'crashk_res' into function reserve_crashkernel() to make the associated code close together. Signed-off-by: Zhen Lei Acked-by: John Donnelly Acked-by: Baoquan He --- arch/arm64/kernel/setup.c | 17 +++-------------- arch/arm64/mm/init.c | 1 + 2 files changed, 4 insertions(+), 14 deletions(-) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index f70573928f1bff0..a81efcc359e4e78 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -225,6 +225,8 @@ static void __init request_standard_resources(void) kernel_code.end = __pa_symbol(__init_begin - 1); kernel_data.start = __pa_symbol(_sdata); kernel_data.end = __pa_symbol(_end - 1); + insert_resource(&iomem_resource, &kernel_code); + insert_resource(&iomem_resource, &kernel_data); num_standard_resources = memblock.memory.cnt; res_size = num_standard_resources * sizeof(*standard_resources); @@ -246,20 +248,7 @@ static void __init request_standard_resources(void) res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1; } - request_resource(&iomem_resource, res); - - if (kernel_code.start >= res->start && - kernel_code.end <= res->end) - request_resource(res, &kernel_code); - if (kernel_data.start >= res->start && - kernel_data.end <= res->end) - request_resource(res, &kernel_data); -#ifdef CONFIG_KEXEC_CORE - /* Userspace will find "Crash kernel" region in /proc/iomem. */ - if (crashk_res.end && crashk_res.start >= res->start && - crashk_res.end <= res->end) - request_resource(res, &crashk_res); -#endif + insert_resource(&iomem_resource, res); } } diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index db63cc885771a52..90f276d46b93bc6 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -109,6 +109,7 @@ static void __init reserve_crashkernel(void) kmemleak_ignore_phys(crash_base); crashk_res.start = crash_base; crashk_res.end = crash_base + crash_size - 1; + insert_resource(&iomem_resource, &crashk_res); } #else static void __init reserve_crashkernel(void) From patchwork Sun Feb 27 03:07:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhen Lei X-Patchwork-Id: 546856 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4E7BC41535 for ; Sun, 27 Feb 2022 03:07:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229780AbiB0DI3 (ORCPT ); Sat, 26 Feb 2022 22:08:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229750AbiB0DI1 (ORCPT ); Sat, 26 Feb 2022 22:08:27 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E1A5206465; Sat, 26 Feb 2022 19:07:50 -0800 (PST) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4K5pH503J8z1FCsp; Sun, 27 Feb 2022 11:03:13 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:48 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:47 +0800 From: Zhen Lei To: 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: Zhen Lei , Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou , "John Donnelly" , Dave Kleikamp Subject: [PATCH v21 3/5] arm64: kdump: reimplement crashkernel=X Date: Sun, 27 Feb 2022 11:07:15 +0800 Message-ID: <20220227030717.1464-4-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20220227030717.1464-1-thunder.leizhen@huawei.com> References: <20220227030717.1464-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Chen Zhou 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 and introduce crashkernel=X,[high,low]. 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 region above DMA zone, which also tries to allocate at least 256M in DMA zone automatically. "crashkernel=Y,low" can be used to allocate specified size low memory. Signed-off-by: Chen Zhou Co-developed-by: Zhen Lei Signed-off-by: Zhen Lei --- arch/arm64/kernel/machine_kexec.c | 9 ++- arch/arm64/kernel/machine_kexec_file.c | 12 ++- arch/arm64/mm/init.c | 106 +++++++++++++++++++++++-- 3 files changed, 115 insertions(+), 12 deletions(-) diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index e16b248699d5c3c..19c2d487cb08feb 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -329,8 +329,13 @@ bool crash_is_nosave(unsigned long pfn) /* in reserved memory? */ addr = __pfn_to_phys(pfn); - if ((addr < crashk_res.start) || (crashk_res.end < addr)) - return false; + if ((addr < crashk_res.start) || (crashk_res.end < addr)) { + if (!crashk_low_res.end) + return false; + + if ((addr < crashk_low_res.start) || (crashk_low_res.end < addr)) + return false; + } if (!kexec_crash_image) return true; diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c index 59c648d51848886..889951291cc0f9c 100644 --- a/arch/arm64/kernel/machine_kexec_file.c +++ b/arch/arm64/kernel/machine_kexec_file.c @@ -65,10 +65,18 @@ static int prepare_elf_headers(void **addr, unsigned long *sz) /* Exclude crashkernel region */ ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); + if (ret) + goto out; + + if (crashk_low_res.end) { + ret = crash_exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end); + if (ret) + goto out; + } - if (!ret) - ret = crash_prepare_elf64_headers(cmem, true, addr, sz); + ret = crash_prepare_elf64_headers(cmem, true, addr, sz); +out: kfree(cmem); return ret; } diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 90f276d46b93bc6..30ae6638ff54c47 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -65,6 +65,44 @@ EXPORT_SYMBOL(memstart_addr); phys_addr_t arm64_dma_phys_limit __ro_after_init; #ifdef CONFIG_KEXEC_CORE +/* Current arm64 boot protocol requires 2MB alignment */ +#define CRASH_ALIGN SZ_2M + +#define CRASH_ADDR_LOW_MAX arm64_dma_phys_limit +#define CRASH_ADDR_HIGH_MAX memblock.current_limit + +/* + * This is an empirical value in x86_64 and taken here directly. Please + * refer to the code comment in reserve_crashkernel_low() of x86_64 for more + * details. + */ +#define DEFAULT_CRASH_KERNEL_LOW_SIZE \ + max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20) + +static int __init reserve_crashkernel_low(unsigned long long low_size) +{ + unsigned long long low_base; + + /* passed with crashkernel=0,low ? */ + if (!low_size) + return 0; + + low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX); + if (!low_base) { + pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size); + return -ENOMEM; + } + + pr_info("crashkernel low memory reserved: 0x%08llx - 0x%08llx (%lld MB)\n", + low_base, low_base + low_size, low_size >> 20); + + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; + insert_resource(&iomem_resource, &crashk_low_res); + + return 0; +} + /* * reserve_crashkernel() - reserves memory for crash kernel * @@ -75,30 +113,79 @@ phys_addr_t arm64_dma_phys_limit __ro_after_init; static void __init reserve_crashkernel(void) { unsigned long long crash_base, crash_size; - unsigned long long crash_max = arm64_dma_phys_limit; + unsigned long long crash_low_size; + unsigned long long crash_max = CRASH_ADDR_LOW_MAX; int ret; + bool fixed_base, high = false; + char *cmdline = boot_command_line; - ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), + /* crashkernel=X[@offset] */ + ret = parse_crashkernel(cmdline, 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(cmdline, 0, &crash_size, &crash_base); + if (ret || !crash_size) + return; + + /* crashkernel=Y,low */ + ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base); + if (ret == -ENOENT) + /* + * crashkernel=Y,low is not specified explicitly, use + * default size automatically. + */ + crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; + else if (ret) + /* crashkernel=Y,low is specified but Y is invalid */ + return; + + /* Mark crashkernel=X,high is specified */ + high = true; + crash_max = CRASH_ADDR_HIGH_MAX; + } + fixed_base = !!crash_base; crash_size = PAGE_ALIGN(crash_size); /* User specifies base address explicitly. */ - if (crash_base) + if (fixed_base) crash_max = crash_base + crash_size; - /* Current arm64 boot protocol requires 2MB alignment */ - crash_base = memblock_phys_alloc_range(crash_size, SZ_2M, +retry: + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, crash_base, crash_max); if (!crash_base) { + /* + * Attempt to fully allocate low memory failed, fall back + * to high memory, the minimum required low memory will be + * reserved later. + */ + if (!fixed_base && (crash_max == CRASH_ADDR_LOW_MAX)) { + crash_max = CRASH_ADDR_HIGH_MAX; + goto retry; + } + pr_warn("cannot allocate crashkernel (size:0x%llx)\n", crash_size); return; } + if (crash_base >= SZ_4G) { + /* + * For case crashkernel=X, low memory is not enough and fall + * back to reserve specified size of memory above 4G, try to + * allocate minimum required memory below 4G again. + */ + if (!high) + crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; + + if (reserve_crashkernel_low(crash_low_size)) { + memblock_phys_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); @@ -107,6 +194,9 @@ static void __init reserve_crashkernel(void) * map. Inform kmemleak so that it won't try to access it. */ kmemleak_ignore_phys(crash_base); + if (crashk_low_res.end) + kmemleak_ignore_phys(crashk_low_res.start); + crashk_res.start = crash_base; crashk_res.end = crash_base + crash_size - 1; insert_resource(&iomem_resource, &crashk_res); From patchwork Sun Feb 27 03:07:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhen Lei X-Patchwork-Id: 546857 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FE4AC4167B for ; Sun, 27 Feb 2022 03:07:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229779AbiB0DI3 (ORCPT ); Sat, 26 Feb 2022 22:08:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229749AbiB0DI1 (ORCPT ); Sat, 26 Feb 2022 22:08:27 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 443D4206473; Sat, 26 Feb 2022 19:07:51 -0800 (PST) Received: from dggpemm500024.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4K5pH602MXz1FDPl; Sun, 27 Feb 2022 11:03:14 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500024.china.huawei.com (7.185.36.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:49 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:48 +0800 From: Zhen Lei To: 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: Zhen Lei , Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou , "John Donnelly" , Dave Kleikamp Subject: [PATCH v21 4/5] of: fdt: Add memory for devices by DT property "linux,usable-memory-range" Date: Sun, 27 Feb 2022 11:07:16 +0800 Message-ID: <20220227030717.1464-5-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20220227030717.1464-1-thunder.leizhen@huawei.com> References: <20220227030717.1464-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Chen Zhou When reserving crashkernel in high memory, some low memory is reserved for crash dump kernel devices and never mapped by the first kernel. This memory range is advertised to crash dump kernel via DT property under /chosen, linux,usable-memory-range = We reused the DT property linux,usable-memory-range and made the low memory region as the second range "BASE2 SIZE2", which keeps compatibility with existing user-space and older kdump kernels. Crash dump kernel reads this property at boot time and call memblock_add() to add the low memory region after memblock_cap_memory_range() has been called. Signed-off-by: Chen Zhou Co-developed-by: Zhen Lei Signed-off-by: Zhen Lei Reviewed-by: Rob Herring Tested-by: Dave Kleikamp --- drivers/of/fdt.c | 33 +++++++++++++++++++++++---------- 1 file changed, 23 insertions(+), 10 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index ec315b060cd50d2..2f248d0acc04830 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -973,16 +973,24 @@ static void __init early_init_dt_check_for_elfcorehdr(unsigned long node) static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND; +/* + * The main usage of linux,usable-memory-range is for crash dump kernel. + * Originally, the number of usable-memory regions is one. Now there may + * be two regions, low region and high region. + * To make compatibility with existing user-space and older kdump, the low + * region is always the last range of linux,usable-memory-range if exist. + */ +#define MAX_USABLE_RANGES 2 + /** * early_init_dt_check_for_usable_mem_range - Decode usable memory range * location from flat tree */ void __init early_init_dt_check_for_usable_mem_range(void) { - const __be32 *prop; - int len; - phys_addr_t cap_mem_addr; - phys_addr_t cap_mem_size; + struct memblock_region rgn[MAX_USABLE_RANGES] = {0}; + const __be32 *prop, *endp; + int len, i; unsigned long node = chosen_node_offset; if ((long)node < 0) @@ -991,16 +999,21 @@ void __init early_init_dt_check_for_usable_mem_range(void) pr_debug("Looking for usable-memory-range property... "); prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len); - if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells))) + if (!prop || (len % (dt_root_addr_cells + dt_root_size_cells))) return; - cap_mem_addr = dt_mem_next_cell(dt_root_addr_cells, &prop); - cap_mem_size = dt_mem_next_cell(dt_root_size_cells, &prop); + endp = prop + (len / sizeof(__be32)); + for (i = 0; i < MAX_USABLE_RANGES && prop < endp; i++) { + rgn[i].base = dt_mem_next_cell(dt_root_addr_cells, &prop); + rgn[i].size = dt_mem_next_cell(dt_root_size_cells, &prop); - pr_debug("cap_mem_start=%pa cap_mem_size=%pa\n", &cap_mem_addr, - &cap_mem_size); + pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n", + i, &rgn[i].base, &rgn[i].size); + } - memblock_cap_memory_range(cap_mem_addr, cap_mem_size); + memblock_cap_memory_range(rgn[0].base, rgn[0].size); + for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++) + memblock_add(rgn[i].base, rgn[i].size); } #ifdef CONFIG_SERIAL_EARLYCON From patchwork Sun Feb 27 03:07:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhen Lei X-Patchwork-Id: 546509 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02D6BC433EF for ; Sun, 27 Feb 2022 03:07:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229788AbiB0DIa (ORCPT ); Sat, 26 Feb 2022 22:08:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229767AbiB0DI2 (ORCPT ); Sat, 26 Feb 2022 22:08:28 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B6D720647E; Sat, 26 Feb 2022 19:07:52 -0800 (PST) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.55]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4K5pH70Q57z1FD6g; Sun, 27 Feb 2022 11:03:15 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) 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 15.1.2308.21; Sun, 27 Feb 2022 11:07:50 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 27 Feb 2022 11:07:49 +0800 From: Zhen Lei To: 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: Zhen Lei , Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou , "John Donnelly" , Dave Kleikamp Subject: [PATCH v21 5/5] docs: kdump: Update the crashkernel description for arm64 Date: Sun, 27 Feb 2022 11:07:17 +0800 Message-ID: <20220227030717.1464-6-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20220227030717.1464-1-thunder.leizhen@huawei.com> References: <20220227030717.1464-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Now arm64 has added support for "crashkernel=X,high" and "crashkernel=Y,low", and implements "crashkernel=X[@offset]" in the same way as x86. So update the Documentation. Signed-off-by: Zhen Lei --- Documentation/admin-guide/kernel-parameters.txt | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index f5a27f067db9ed9..63098786c93828c 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -789,7 +789,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, X86-64] Select a region under 4G first, and + [KNL, X86-64, ARM64] Select a region under 4G first, and fall back to reserve region above 4G when '@offset' hasn't been specified. See Documentation/admin-guide/kdump/kdump.rst for further details. @@ -802,20 +802,20 @@ Documentation/admin-guide/kdump/kdump.rst for an example. crashkernel=size[KMG],high - [KNL, X86-64] range could be above 4G. Allow kernel + [KNL, X86-64, ARM64] range could be above 4G. Allow kernel to allocate physical memory region from top, so could be above 4G if system have more than 4G ram installed. Otherwise memory region will be allocated below 4G, if available. It will be ignored if crashkernel=X is specified. crashkernel=size[KMG],low - [KNL, X86-64] range under 4G. When crashkernel=X,high + [KNL, X86-64, ARM64] range under 4G. When crashkernel=X,high is passed, kernel could allocate physical memory region above 4G, that cause second kernel crash on system that require some amount of low memory, e.g. swiotlb requires at least 64M+32K low memory, also enough extra low memory is needed to make sure DMA buffers for 32-bit - devices won't run out. Kernel would try to allocate at + devices won't run out. Kernel would try to allocate at least 256M below 4G automatically. This one let user to specify own low range under 4G for second kernel instead.