From nobody Thu May 9 01:42:43 2024 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 A782EC76195 for ; Tue, 28 Mar 2023 03:56:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232842AbjC1Dz7 (ORCPT ); Mon, 27 Mar 2023 23:55:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232676AbjC1Dz1 (ORCPT ); Mon, 27 Mar 2023 23:55:27 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7417930CB; Mon, 27 Mar 2023 20:55:20 -0700 (PDT) Received: from dggpemm500016.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Plwkc2F6ZzKvxd; Tue, 28 Mar 2023 11:52:56 +0800 (CST) Received: from huawei.com (10.67.174.205) by dggpemm500016.china.huawei.com (7.185.36.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Tue, 28 Mar 2023 11:55:18 +0800 From: Chen Jiahao To: , , , , , , , , , , , CC: , , , Subject: [PATCH -next v2 1/2] riscv: kdump: Implement crashkernel=X,[high,low] Date: Tue, 28 Mar 2023 19:51:49 +0800 Message-ID: <20230328115150.2700016-2-chenjiahao16@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230328115150.2700016-1-chenjiahao16@huawei.com> References: <20230328115150.2700016-1-chenjiahao16@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.67.174.205] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500016.china.huawei.com (7.185.36.25) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On riscv, the current crash kernel allocation logic is trying to allocate within 32bit addressible memory region by default, if failed, try to allocate without 4G restriction. In need of saving DMA zone memory while allocating a relatively large crash kernel region, allocating the reserved memory top down in high memory, without overlapping the DMA zone, is a mature solution. Here introduce the parameter option crashkernel=3DX,[high,low]. One can reserve the crash kernel from high memory above DMA zone range by explicitly passing "crashkernel=3DX,high"; or reserve a memory range below 4G with "crashkernel=3DX,low". Signed-off-by: Chen Jiahao --- arch/riscv/kernel/setup.c | 5 ++++ arch/riscv/mm/init.c | 63 ++++++++++++++++++++++++++++++++++++--- 2 files changed, 64 insertions(+), 4 deletions(-) diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index 5d3184cbf518..ea84e5047c23 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -176,6 +176,11 @@ static void __init init_resources(void) if (ret < 0) goto error; } + if (crashk_low_res.start !=3D crashk_low_res.end) { + ret =3D add_resource(&iomem_resource, &crashk_low_res); + if (ret < 0) + goto error; + } #endif =20 #ifdef CONFIG_CRASH_DUMP diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 478d6763a01a..b7708cc467fa 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -1152,6 +1152,28 @@ static inline void setup_vm_final(void) } #endif /* CONFIG_MMU */ =20 +/* Reserve 128M low memory by default for swiotlb buffer */ +#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20) + +static int __init reserve_crashkernel_low(unsigned long long low_size) +{ + unsigned long long low_base; + + low_base =3D memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_= limit); + if (!low_base) { + pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_si= ze); + return -ENOMEM; + } + + pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)= \n", + low_base, low_base + low_size, low_size >> 20); + + crashk_low_res.start =3D low_base; + crashk_low_res.end =3D low_base + low_size - 1; + + return 0; +} + /* * reserve_crashkernel() - reserves memory for crash kernel * @@ -1163,6 +1185,7 @@ static void __init reserve_crashkernel(void) { unsigned long long crash_base =3D 0; unsigned long long crash_size =3D 0; + unsigned long long crash_low_size =3D 0; unsigned long search_start =3D memblock_start_of_DRAM(); unsigned long search_end =3D memblock_end_of_DRAM(); =20 @@ -1182,8 +1205,30 @@ static void __init reserve_crashkernel(void) =20 ret =3D parse_crashkernel(boot_command_line, memblock_phys_mem_size(), &crash_size, &crash_base); - if (ret || !crash_size) + if (ret =3D=3D -ENOENT) { + /* + * crashkernel=3DX,[high,low] can be specified or not, but + * invalid value is not allowed. + */ + ret =3D parse_crashkernel_high(boot_command_line, 0, &crash_size, &crash= _base); + if (ret || !crash_size) + return; + + /* + * crashkernel=3DY,low is valid only when crashkernel=3DX,high + * is passed and high memory is reserved successful. + */ + ret =3D parse_crashkernel_low(boot_command_line, 0, &crash_low_size, &cr= ash_base); + if (ret =3D=3D -ENOENT) + crash_low_size =3D DEFAULT_CRASH_KERNEL_LOW_SIZE; + else if (ret) + return; + + search_start =3D dma32_phys_limit; + } else if (ret || !crash_size) { + /* Invalid argument value specified */ return; + } =20 crash_size =3D PAGE_ALIGN(crash_size); =20 @@ -1201,16 +1246,26 @@ static void __init reserve_crashkernel(void) */ crash_base =3D memblock_phys_alloc_range(crash_size, PMD_SIZE, search_start, - min(search_end, (unsigned long) SZ_4G)); + min(search_end, (unsigned long)dma32_phys_limit)); if (crash_base =3D=3D 0) { - /* Try again without restricting region to 32bit addressible memory */ + /* Try again above the region of 32bit addressible memory */ crash_base =3D memblock_phys_alloc_range(crash_size, PMD_SIZE, - search_start, search_end); + max(search_start, (unsigned long)dma32_phys_limit), + search_end); if (crash_base =3D=3D 0) { pr_warn("crashkernel: couldn't allocate %lldKB\n", crash_size >> 10); return; } + + if (!crash_low_size) + crash_low_size =3D DEFAULT_CRASH_KERNEL_LOW_SIZE; + } + + if ((crash_base > dma32_phys_limit - crash_low_size) && + crash_low_size && reserve_crashkernel_low(crash_low_size)) { + memblock_phys_free(crash_base, crash_size); + return; } =20 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n", --=20 2.31.1 From nobody Thu May 9 01:42:43 2024 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 F114DC77B60 for ; Tue, 28 Mar 2023 03:55:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232777AbjC1Dzx (ORCPT ); Mon, 27 Mar 2023 23:55:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232487AbjC1Dz0 (ORCPT ); Mon, 27 Mar 2023 23:55:26 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E016199A; Mon, 27 Mar 2023 20:55:20 -0700 (PDT) Received: from dggpemm500016.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4Plwmp43LRzKpkX; Tue, 28 Mar 2023 11:54:50 +0800 (CST) Received: from huawei.com (10.67.174.205) by dggpemm500016.china.huawei.com (7.185.36.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Tue, 28 Mar 2023 11:55:18 +0800 From: Chen Jiahao To: , , , , , , , , , , , CC: , , , Subject: [PATCH -next v2 2/2] docs: kdump: Update the crashkernel description for riscv Date: Tue, 28 Mar 2023 19:51:50 +0800 Message-ID: <20230328115150.2700016-3-chenjiahao16@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230328115150.2700016-1-chenjiahao16@huawei.com> References: <20230328115150.2700016-1-chenjiahao16@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.67.174.205] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500016.china.huawei.com (7.185.36.25) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Now "crashkernel=3D" parameter on riscv has been updated to support crashkernel=3DX,[high,low]. Through which we can reserve memory region above/within 32bit addressible DMA zone. Here update the parameter description accordingly. Signed-off-by: Chen Jiahao --- Documentation/admin-guide/kernel-parameters.txt | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index 9bc3813bce8f..a947d3d7c85c 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -866,7 +866,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, X86-64, ARM64] Select a region under 4G first, and + [KNL, X86-64, ARM64, RISCV] 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. @@ -879,14 +879,14 @@ Documentation/admin-guide/kdump/kdump.rst for an example. =20 crashkernel=3Dsize[KMG],high - [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. + [KNL, X86-64, ARM64, RISCV] 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=3DX is specified. crashkernel=3Dsize[KMG],low - [KNL, X86-64, ARM64] range under 4G. When crashkernel=3DX,high + [KNL, X86-64, ARM64, RISCV] range under 4G. When crashkernel=3DX,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 @@ -897,6 +897,7 @@ size is platform dependent. --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB) --> arm64: 128MiB + --> riscv: 128MiB This one lets the user specify own low range under 4G for second kernel instead. 0: to disable low allocation. --=20 2.31.1