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=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no 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 4162DC6379D for ; Thu, 19 Nov 2020 20:55:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB66A2224A for ; Thu, 19 Nov 2020 20:54:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="lJgJ0exM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726335AbgKSUy7 (ORCPT ); Thu, 19 Nov 2020 15:54:59 -0500 Received: from aserp2130.oracle.com ([141.146.126.79]:52242 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725907AbgKSUy6 (ORCPT ); Thu, 19 Nov 2020 15:54:58 -0500 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0AJKsL7g122414; Thu, 19 Nov 2020 20:54:21 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=content-type : mime-version : subject : from : in-reply-to : date : cc : content-transfer-encoding : message-id : references : to; s=corp-2020-01-29; bh=jUdxTuSHtsuS3WsA4fd2+z7O66RBMlImwnbK4D6tItg=; b=lJgJ0exMOfKGfTU9qWgUxdSdYpQ7NX5JU5l4WBWJenUkHxDJaa3j2YYohjmeLEOYdezl qxAAEJlDVNSTe45OQ9YCpmse4BssJrkQEjgi8DX3EeMVH6vZIzLDeP7rBo11d7AGWaqK Vqzsc0iqyPKC71ssR9QcY3jJpZ/vcus6xBma3KGXUfHRaL5HumWoF7gkwS4V/QEhY4W5 4VSglFI4FtI9HPmrdOX6VXsxrX6su1gDEqPGxTC4OnJ5g/NARWHeyaV6SrlWCGNUwvfj ue32zhNoTBN3XjboQUS7Q2x1OKtA6qaNwi12imQfb+dNYsh5KhRxi5H/x8kN9aRY1lTa lA== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2130.oracle.com with ESMTP id 34t4rb7s1m-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 19 Nov 2020 20:54:21 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0AJKnjGO117244; Thu, 19 Nov 2020 20:52:15 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 34uspwp9ru-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 19 Nov 2020 20:52:15 +0000 Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 0AJKqDZq028770; Thu, 19 Nov 2020 20:52:13 GMT Received: from dhcp-10-159-251-58.vpn.oracle.com (/10.159.251.58) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 19 Nov 2020 12:52:13 -0800 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\)) Subject: Re: [PATCH 1/1] kernel/crash_core.c - Add crashkernel=auto for x86 and ARM From: Saeed Mirzamohammadi In-Reply-To: Date: Thu, 19 Nov 2020 12:52:10 -0800 Cc: John Donnelly , stable@vger.kernel.org, Dave Young , Baoquan He , Vivek Goyal , Jonathan Corbet , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , the arch/x86 maintainers , "H. Peter Anvin" , Bjorn Andersson , Shawn Guo , Li Yang , Vinod Koul , Arnd Bergmann , Anson Huang , Geert Uytterhoeven , Michael Walle , Krzysztof Kozlowski , Olof Johansson , "Martin K. Petersen" , =?utf-8?Q?Diego_Elio_Petten=C3=B2?= , Miguel Ojeda , Randy Dunlap , kexec@lists.infradead.org, linux-doc@vger.kernel.org, Linux Kernel Mailing List , linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: quoted-printable Message-Id: <8F545EB3-9AA4-45AE-84D2-7C0B5CF43FF6@oracle.com> References: <20201118232431.21832-1-saeed.mirzamohammadi@oracle.com> To: Kairui Song X-Mailer: Apple Mail (2.3608.120.23.2.4) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9810 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 malwarescore=0 mlxscore=0 bulkscore=0 suspectscore=3 adultscore=0 spamscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011190142 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9810 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 clxscore=1015 malwarescore=0 impostorscore=0 lowpriorityscore=0 priorityscore=1501 mlxlogscore=999 adultscore=0 phishscore=0 suspectscore=3 spamscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011190143 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, [I=E2=80=99m resending this email as it failed to be sent to certain = emails.] > And I think crashkernel=3Dauto could be used as an indicator that user > want the kernel to control the crashkernel size, so some further work > could be done to adjust the crashkernel more accordingly. eg. when > memory encryption is enabled, increase the crashkernel value for the > auto estimation, as it's known to consume more crashkernel memory. >=20 Thanks for the suggestion! I tried to keep it simple and leave it to the = user to change Kconfig in case a different range is needed. Based on = experience, these ranges work well for most of the regular cases. >=20 > But why not make it arch-independent? This crashkernel=3Dauto idea > should simply work with every arch. Thanks! I=E2=80=99ll be making it arch-independent in the v2 patch. >=20 > I think this rounding may be better moved to the arch specified part > where parse_crashkernel is called? Thanks for the suggestion. Could you please elaborate why do we need to = do that? Thanks, Saeed