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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1BB6DC77B61 for ; Sat, 8 Apr 2023 02:01:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229865AbjDHCBf (ORCPT ); Fri, 7 Apr 2023 22:01:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229610AbjDHCBc (ORCPT ); Fri, 7 Apr 2023 22:01:32 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 622A2E06C; Fri, 7 Apr 2023 19:01:31 -0700 (PDT) Received: from dggpemm500006.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Ptdfw3sYTznYd8; Sat, 8 Apr 2023 09:58:00 +0800 (CST) Received: from [10.174.178.55] (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 15.1.2507.23; Sat, 8 Apr 2023 10:01:28 +0800 Subject: Re: [PATCH -next v3 2/2] docs: kdump: Update the crashkernel description for riscv To: Chen Jiahao , , , , CC: , , , , , , , , , , References: <20230406220206.3067006-1-chenjiahao16@huawei.com> <20230406220206.3067006-3-chenjiahao16@huawei.com> From: "Leizhen (ThunderTown)" Message-ID: Date: Sat, 8 Apr 2023 10:01:28 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20230406220206.3067006-3-chenjiahao16@huawei.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023/4/7 6:02, Chen Jiahao wrote: > Now "crashkernel=" parameter on riscv has been updated to support > crashkernel=X,[high,low]. Through which we can reserve memory region > above/within 32bit addressible DMA zone. > > Here update the parameter description accordingly. Reviewed-by: Zhen Lei > > 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/Documentation/admin-guide/kernel-parameters.txt > index 54702bd488eb..41865aae9eaa 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. > > crashkernel=size[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=X is specified. > crashkernel=size[KMG],low > - [KNL, X86-64, ARM64] range under 4G. When crashkernel=X,high > + [KNL, X86-64, ARM64, RISCV] 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 > @@ -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. > -- Regards, Zhen Lei