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 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 C0337C77B61 for ; Tue, 25 Apr 2023 13:21:19 +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-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:References:CC:To:From:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=aNK3/4YH0/nMmzvdJmFf/ltanh1ENIJyla3BWhVNqbs=; b=1YjWO8lKxwszYb gk9FHv5cFxn2qEigivR0eZpGnNKZR23Eqr+5RDlqAaCQ15BMRcLqQkIgvv0wsKc4cTI8RrxvYWe9x 0MEUsm3iX6o7DMxmvj/lf8Cayja0HJntb0p6VBaROPGwxix5yshcY0wR7Dno+vlIGExfsAkX10rD+ M4wID86mb7X7CXlFNljULF+FKNrppUE38L7sUiaOXl5MVbPMSFLeV5htMFX8YwNKf/hg94oQXcEqD ix9hJ+P0Q6mgJyc3zfGq0N6rWPGmCzHGwFGMUMftvoTXIdX1kpjeUcxbD0PvX3hyO+24TMyjKovpO mrwbZ864g8RL7lo9j63g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1prIbb-001CVs-1h; Tue, 25 Apr 2023 13:21:15 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1prIbX-001COm-3D; Tue, 25 Apr 2023 13:21:14 +0000 Received: from dggpemm500016.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Q5MwY6SF8zpT8Q; Tue, 25 Apr 2023 21:17:01 +0800 (CST) Received: from [10.67.108.26] (10.67.108.26) 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; Tue, 25 Apr 2023 21:20:53 +0800 Message-ID: Date: Tue, 25 Apr 2023 21:20:53 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH -next v4 0/2] support allocating crashkernel above 4G explicitly on riscv Content-Language: en-US From: "chenjiahao (C)" To: , , , CC: , , , , , , , , , , , References: <20230410130553.3226347-1-chenjiahao16@huawei.com> In-Reply-To: <20230410130553.3226347-1-chenjiahao16@huawei.com> X-Originating-IP: [10.67.108.26] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) 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-20230425_062112_442597_6298EDD6 X-CRM114-Status: GOOD ( 16.79 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 2023/4/10 21:05, Chen Jiahao wrote: > 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. > Hence this patchset introduces the parameter option crashkernel=X,[high,low]. > > One can reserve the crash kernel from high memory above DMA zone range > by explicitly passing "crashkernel=X,high"; or reserve a memory range > below 4G with "crashkernel=X,low". Besides, there are few rules need > to take notice: > 1. "crashkernel=X,[high,low]" will be ignored if "crashkernel=size" > is specified. > 2. "crashkernel=X,low" is valid only when "crashkernel=X,high" is passed > and there is enough memory to be allocated under 4G. > 3. When allocating crashkernel above 4G and no "crashkernel=X,low" is > specified, a 128M low memory will be allocated automatically for > swiotlb bounce buffer. > See Documentation/admin-guide/kernel-parameters.txt for more information. > > To verify loading the crashkernel, adapted kexec-tools is attached below: > https://github.com/chenjh005/kexec-tools/tree/build-test-riscv-v2 > > Following test cases have been performed as expected: > 1) crashkernel=256M //low=256M > 2) crashkernel=1G //low=1G > 3) crashkernel=4G //high=4G, low=128M(default) > 4) crashkernel=4G crashkernel=256M,high //high=4G, low=128M(default), high is ignored > 5) crashkernel=4G crashkernel=256M,low //high=4G, low=128M(default), low is ignored > 6) crashkernel=4G,high //high=4G, low=128M(default) > 7) crashkernel=256M,low //low=0M, invalid > 8) crashkernel=4G,high crashkernel=256M,low //high=4G, low=256M > 9) crashkernel=4G,high crashkernel=4G,low //high=0M, low=0M, invalid > 10) crashkernel=512M@0xd0000000 //low=512M > 11) crashkernel=1G@0xe0000000 //high=0M, low=0M, no enough low memory, failed > > Changes since [v4]: > 1. Update some imprecise code comments for cmdline parsing. > > Changes since [v3]: > 1. Update to print warning and return explicitly on failure when > crashkernel=size@offset is specified. Not changing the result > in this case but making the logic more straightforward. > 2. Some minor cleanup. > > Changes since [v2]: > 1. Update the allocation logic to ensure the high crashkernel > region is reserved strictly above dma32_phys_limit. > 2. Clean up some minor format problems. > > Chen Jiahao (2): > riscv: kdump: Implement crashkernel=X,[high,low] > docs: kdump: Update the crashkernel description for riscv > > .../admin-guide/kernel-parameters.txt | 15 ++-- > arch/riscv/kernel/setup.c | 5 ++ > arch/riscv/mm/init.c | 71 +++++++++++++++++-- > 3 files changed, 79 insertions(+), 12 deletions(-) Hi folks, The current version has fix all problems up-to-date, please let me know if there is any other bug, or somewhere not quiet correct. Thanks for looking into this. Best Regards, Jiahao _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec