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 8CD81C76196 for ; Fri, 7 Apr 2023 12:04:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240574AbjDGMEB (ORCPT ); Fri, 7 Apr 2023 08:04:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240247AbjDGMEA (ORCPT ); Fri, 7 Apr 2023 08:04:00 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 275D683CD; Fri, 7 Apr 2023 05:03:59 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B654760F87; Fri, 7 Apr 2023 12:03:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36B44C4339B; Fri, 7 Apr 2023 12:03:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680869038; bh=hj8WZn4fsaNVXzouph4VuJoSDtm/pAjQ+hGj5NXmwD0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cBXLq4fagWKRTewxo4p5y+yltMfue1gHv9h6Rhkf+kT90l5ObTPyf5Q+HxCMGQAsM 1WP18Sp/Ya3w+QiZ4Uku4/jcrSyIhhTDl6GoeWbpZfrxfYH144zC7BdFXcOmN3Bs8l ixgsTZd59XKKamoXJiCD5OBzTnOMIL4T96AiI38v7Ttj3fY3eZPYH/jj8zcKKxqUjw yZoR54HGahnG32BUoRdGl3XUEBDexCXzAufgslwOsGCS+z+ydlK/+dWroXXTzS6rYo BzhTRRDstfoWaFx2kUjdCg3egxn1cf8mY8FaYa/WqcsUV2RCUa8bxxeEYIVS0jpejz CO8A+lDkofXZw== Date: Fri, 7 Apr 2023 14:03:52 +0200 From: Simon Horman To: Guo Ren Cc: Chen Jiahao , linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, kexec@lists.infradead.org, linux-doc@vger.kernel.org, paul.walmsley@sifive.com, palmer@dabbelt.com, conor.dooley@microchip.com, heiko@sntech.de, bjorn@rivosinc.com, alex@ghiti.fr, akpm@linux-foundation.org, atishp@rivosinc.com, bhe@redhat.com, thunder.leizhen@huawei.com Subject: Re: [PATCH -next v3 1/2] riscv: kdump: Implement crashkernel=X,[high,low] Message-ID: References: <20230406220206.3067006-1-chenjiahao16@huawei.com> <20230406220206.3067006-2-chenjiahao16@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Fri, Apr 07, 2023 at 05:06:24PM +0800, Guo Ren wrote: > On Thu, Apr 6, 2023 at 10:06 PM 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. > > Here introduce 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". > Asked-by: Guo Ren Perhaps 'Acked-by' :)