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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5173AC433DB for ; Sat, 20 Feb 2021 03:27:05 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0085764EE0 for ; Sat, 20 Feb 2021 03:27:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0085764EE0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=N5+a/MK/vHyjguoiq2Xko+5HYrCi50qdtfiOSF/7WNc=; b=02dA0uLRuTGI6P5497eTvnc2H I7dg/eUhW7QASgej7T7qv6v/xxXvllVDz4q7d8wnM7QLL/aOgo3TWK1eLWlhBxOfl1gQs6yHwYyjD b5yK04EZzfxqgnZOeERK35NLRz2QEHoiJnjNl33eyURf1nSABaI6Rad2OAtP98V7YBFMwvJy8wDxE T1bVyvzybRq2V4Mlh6RzGesmq60IiRBWfeGGxI3aGnfZSzur3doankhid9q9xi2JwqplcPDf0p8GM PPR/s5QotSWp/IY7h2Vn9DwUFrjByeLJop7EirEPihzEqWUYHOAKHn1VKtt2j1Nm1g3VE2uNsTbDr CuvB7+BkA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lDIti-0005Ws-Ix; Sat, 20 Feb 2021 03:25:34 +0000 Received: from szxga06-in.huawei.com ([45.249.212.32]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lDIte-0005Vd-8r; Sat, 20 Feb 2021 03:25:32 +0000 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4DjDM00FpZzjP9W; Sat, 20 Feb 2021 11:24:12 +0800 (CST) Received: from [10.174.176.191] (10.174.176.191) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.498.0; Sat, 20 Feb 2021 11:25:20 +0800 Subject: Re: [PATCH v14 11/11] kdump: update Documentation about crashkernel To: Baoquan He References: <20210130071025.65258-1-chenzhou10@huawei.com> <20210130071025.65258-12-chenzhou10@huawei.com> <20210218083822.GL2871@MiWiFi-R3L-srv> From: chenzhou Message-ID: <4fbc4cdc-9888-bf34-1fcc-f5bcb0349042@huawei.com> Date: Sat, 20 Feb 2021 11:25:19 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20210218083822.GL2871@MiWiFi-R3L-srv> X-Originating-IP: [10.174.176.191] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210219_222530_903176_C05BFE32 X-CRM114-Status: GOOD ( 20.29 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: wangkefeng.wang@huawei.com, linux-doc@vger.kernel.org, catalin.marinas@arm.com, huawei.libin@huawei.com, guohanjun@huawei.com, will@kernel.org, corbet@lwn.net, mingo@redhat.com, dyoung@redhat.com, John.P.donnelly@oracle.com, arnd@arndb.de, xiexiuqi@huawei.com, horms@verge.net.au, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, james.morse@arm.com, rppt@kernel.org, prabhakar.pkin@gmail.com, nsaenzjulienne@suse.de Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2021/2/18 16:40, Baoquan He wrote: > On 01/30/21 at 03:10pm, Chen Zhou wrote: >> For arm64, the behavior of crashkernel=X has been changed, which >> 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 high region above >> DMA zone, which also tries to allocate at least 256M low memory in >> DMA zone automatically and "crashkernel=Y,low" can be used to allocate >> specified size low memory. >> >> So update the Documentation. > Nice document adding which also takes care of x86 code implementation, > thanks. By the way, maybe you can remove John's 'Tested-by' since it > doesn't make much sense to test a document patch. I will remove the Tested-by in next version. > > Acked-by: Baoquan He > >> Signed-off-by: Chen Zhou >> Tested-by: John Donnelly >> --- >> Documentation/admin-guide/kdump/kdump.rst | 22 ++++++++++++++++--- >> .../admin-guide/kernel-parameters.txt | 11 ++++++++-- >> 2 files changed, 28 insertions(+), 5 deletions(-) >> >> diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst >> index 75a9dd98e76e..0877c76f8015 100644 >> --- a/Documentation/admin-guide/kdump/kdump.rst >> +++ b/Documentation/admin-guide/kdump/kdump.rst >> @@ -299,7 +299,16 @@ Boot into System Kernel >> "crashkernel=64M@16M" tells the system kernel to reserve 64 MB of memory >> starting at physical address 0x01000000 (16MB) for the dump-capture kernel. >> >> - On x86 and x86_64, use "crashkernel=64M@16M". >> + On x86 use "crashkernel=64M@16M". >> + >> + On x86_64, use "crashkernel=X" to select a region under 4G first, and >> + fall back to reserve region above 4G. And go for high allocation >> + directly if the required size is too large. >> + We can also use "crashkernel=X,high" to select a region above 4G, which >> + also tries to allocate at least 256M below 4G automatically and >> + "crashkernel=Y,low" can be used to allocate specified size low memory. >> + Use "crashkernel=Y@X" if you really have to reserve memory from specified >> + start address X. >> >> On ppc64, use "crashkernel=128M@32M". >> >> @@ -316,8 +325,15 @@ Boot into System Kernel >> kernel will automatically locate the crash kernel image within the >> first 512MB of RAM if X is not given. >> >> - On arm64, use "crashkernel=Y[@X]". Note that the start address of >> - the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). >> + On arm64, use "crashkernel=X" to try low allocation in DMA zone and >> + fall back to high allocation if it fails. >> + We can also use "crashkernel=X,high" to select a high region above >> + DMA zone, which also tries to allocate at least 256M low memory in >> + DMA zone automatically. >> + "crashkernel=Y,low" can be used to allocate specified size low memory. >> + Use "crashkernel=Y@X" if you really have to reserve memory from >> + specified start address X. Note that the start address of the kernel, >> + X if explicitly specified, must be aligned to 2MiB (0x200000). >> >> Load the Dump-capture Kernel >> ============================ >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >> index a10b545c2070..908e5c8b61ba 100644 >> --- a/Documentation/admin-guide/kernel-parameters.txt >> +++ b/Documentation/admin-guide/kernel-parameters.txt >> @@ -738,6 +738,9 @@ >> [KNL, X86-64] Select a region under 4G first, and >> fall back to reserve region above 4G when '@offset' >> hasn't been specified. >> + [KNL, arm64] Try low allocation in DMA zone and fall back >> + to high allocation if it fails when '@offset' hasn't been >> + specified. >> See Documentation/admin-guide/kdump/kdump.rst for further details. >> >> crashkernel=range1:size1[,range2:size2,...][@offset] >> @@ -754,6 +757,8 @@ >> Otherwise memory region will be allocated below 4G, if >> available. >> It will be ignored if crashkernel=X is specified. >> + [KNL, arm64] range in high memory. >> + Allow kernel to allocate physical memory region from top. >> crashkernel=size[KMG],low >> [KNL, X86-64] range under 4G. When crashkernel=X,high >> is passed, kernel could allocate physical memory region >> @@ -762,13 +767,15 @@ >> 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 >> - at least 256M below 4G automatically. >> + least 256M below 4G automatically. >> This one let user to specify own low range under 4G >> for second kernel instead. >> 0: to disable low allocation. >> It will be ignored when crashkernel=X,high is not used >> or memory reserved is below 4G. >> - >> + [KNL, arm64] range in low memory. >> + This one let user to specify a low range in DMA zone for >> + crash dump kernel. >> cryptomgr.notests >> [KNL] Disable crypto self-tests >> >> -- >> 2.20.1 >> > . > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel