From patchwork Mon Apr 10 13:05:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Jiahao X-Patchwork-Id: 13206359 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 77403C77B61 for ; Mon, 10 Apr 2023 13:06:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ATVaosuyIXc/YqwPYQJYVLR/EYq+dE/EPd8Y7hEZkAA=; b=ioyv6D/vaZPmX5 rqk6DHQrNSOXmTTiNsnPAtUMh3IxeRP9yBLzvTiC8JR3wks+snOC3oO4PLpQb+t0A5kkN0j+yk4wv L9S2W0luTnsHE2Mxe9+YUV9v+mHPsIUzEXvnJ0rhgI3vk9Suwgh80E8MMxN29RyDSs+i5yrpoYG0J HmF0LKxdes1z9Tjh5vUvlkyz2zEd5khG84+VkRzJez24WTXHkIKl2FGn8aSfFFA2E9zVH0QM7MExF wuGmh51eQLvFOaeEGovG7qcQC6Wt7eCGoM6qP7sADEmpdWt1RQvYuA9Jvy581sqT1hONzCAMGcTMA Cfs6EY316ATscBJCynig==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1plrDs-00FGI3-22; Mon, 10 Apr 2023 13:06:16 +0000 Received: from szxga08-in.huawei.com ([45.249.212.255]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1plrDn-00FGEt-2C; Mon, 10 Apr 2023 13:06:13 +0000 Received: from dggpemm500016.china.huawei.com (unknown [172.30.72.54]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Pw8Jl2BrNz17RwY; Mon, 10 Apr 2023 21:02:31 +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 15.1.2507.23; Mon, 10 Apr 2023 21:06:02 +0800 From: Chen Jiahao To: , , , CC: , , , , , , , , , , , Subject: [PATCH -next v4 2/2] docs: kdump: Update the crashkernel description for riscv Date: Mon, 10 Apr 2023 21:05:53 +0800 Message-ID: <20230410130553.3226347-3-chenjiahao16@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230410130553.3226347-1-chenjiahao16@huawei.com> References: <20230410130553.3226347-1-chenjiahao16@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.67.174.205] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500016.china.huawei.com (7.185.36.25) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230410_060612_072524_70D1A675 X-CRM114-Status: GOOD ( 10.31 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org 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. Signed-off-by: Chen Jiahao Reviewed-by: Guo Ren Reviewed-by: Simon Horman Reviewed-by: Zhen Lei --- 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.