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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 ECA3CC3F2CD for ; Wed, 4 Mar 2020 07:19:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C98F7215A4 for ; Wed, 4 Mar 2020 07:19:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728433AbgCDHTD (ORCPT ); Wed, 4 Mar 2020 02:19:03 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:39196 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725971AbgCDHTD (ORCPT ); Wed, 4 Mar 2020 02:19:03 -0500 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 02479nn2143874; Wed, 4 Mar 2020 02:18:46 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yj3erqu80-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 04 Mar 2020 02:18:45 -0500 Received: from m0098404.ppops.net (m0098404.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 0247Ah4i002626; Wed, 4 Mar 2020 02:18:45 -0500 Received: from ppma03wdc.us.ibm.com (ba.79.3fa9.ip4.static.sl-reverse.com [169.63.121.186]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yj3erqu7j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 04 Mar 2020 02:18:45 -0500 Received: from pps.filterd (ppma03wdc.us.ibm.com [127.0.0.1]) by ppma03wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 0247G3wu030502; Wed, 4 Mar 2020 07:18:44 GMT Received: from b03cxnp08027.gho.boulder.ibm.com (b03cxnp08027.gho.boulder.ibm.com [9.17.130.19]) by ppma03wdc.us.ibm.com with ESMTP id 2yffk711fg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 04 Mar 2020 07:18:44 +0000 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp08027.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0247Ih6456230288 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 4 Mar 2020 07:18:43 GMT Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EDF6FBE051; Wed, 4 Mar 2020 07:18:42 +0000 (GMT) Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 33460BE056; Wed, 4 Mar 2020 07:18:39 +0000 (GMT) Received: from LeoBras (unknown [9.85.177.129]) by b03ledav005.gho.boulder.ibm.com (Postfix) with ESMTP; Wed, 4 Mar 2020 07:18:38 +0000 (GMT) Message-ID: <621dd76a8e0b449db66ba2c3ad20fb2c743a1f1b.camel@linux.ibm.com> Subject: Re: [PATCH 1/1] powerpc/kernel: Enables memory hot-remove after reboot on pseries guests From: Leonardo Bras To: Bharata B Rao Cc: ndfont@gmail.com, "linux-kernel@vger.kernel.org" , arbab@linux.ibm.com, Claudio Carvalho , Michael Roth , Paul Mackerras , Greg Kroah-Hartman , Thomas Gleixner , linuxppc-dev , Hari Bathini Date: Wed, 04 Mar 2020 04:18:32 -0300 In-Reply-To: References: <20200228060439.52749-1-leonardo@linux.ibm.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-sL1rgkZbhhqGAClQPGna" User-Agent: Evolution 3.34.4 (3.34.4-1.fc31) MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-03-03_08:2020-03-03,2020-03-03 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 malwarescore=0 impostorscore=0 mlxscore=0 phishscore=0 spamscore=0 clxscore=1015 suspectscore=0 bulkscore=0 adultscore=0 priorityscore=1501 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003040055 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-sL1rgkZbhhqGAClQPGna Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hello Bharata, thanks for this feedback! On Wed, 2020-03-04 at 10:13 +0530, Bharata B Rao wrote: > Hi, >=20 > I tried this a few years back > (https://patchwork.ozlabs.org/patch/800142/) and didn't pursue it > further because at that time, it was felt that the approach might not > work for PowerVM guests, because all the present memory except RMA > gets marked as hot-pluggable by PowerVM. This discussion is not > present in the above thread, but during my private discussions with > Reza and Nathan, it was noted that making all that memory as MOVABLE > is not preferable for PowerVM guests as we might run out of memory for > kernel allocations. Humm, this makes sense. But with mu change, these pieces of memory only get into ZONE_MOVABLE if the boot parameter 'movable_node' gets passed to guest kernel.=20 So, even if we are unable to sort out some flag combination that work fine for both use-cases, if PowerVM don't pass 'movable_node' as boot parameter to kernel, it will behave just as today. What are your thoughts on that? Best regards, Leonardo Bras --=-sL1rgkZbhhqGAClQPGna Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEMdeUgIzgjf6YmUyOlQYWtz9SttQFAl5fVkgACgkQlQYWtz9S ttTcqw/+KygdoD/4CjbE1qeM/UgE8K0p7R0VEctB20M41BvMj0yC4c+sHA+CPbkW o273+a2KeG6le9K5sp7Gy7ElrSqczN2AuInkYHJ2AezPBw4pDRGTBTp2a91ivGdf DidQrsx856IW6qouXsqo1NOIwDicuuy12/HCGzqvkFGaY6/89FdihM5FbBTtQ8Ps DRKJnOwhz5gr0vcYLHtJdfyzuzPM4VzFDIYmTH3+vLgfYvfQFt0S4RqmoEsI0AXR +u33lx995GzsafkladGDNKbX/v/xt9MRImGdhuHKmH5+ccnR/GankA5W4mOR+hw/ 1caHR2Sn5bXlHwtJjL9OslJmPfWIho8D/v9SmRfJIgfE0Br9hNMrl9ttB4V9LmUV Oe9e3hyyR3F0fVpKLrYvA9KQJ7ocm3I1e2hEwxYphtDiasCVCCFHD/Ue2sHpaNc2 0TcoIsWifC1TBMq2pMWIRVlkdee0B1V6Sj1pmyoRpuH7ZweP41ge2aG4Yw7CDStd TM7jngOQymRfgLrG1jjSnEjtCEG/ZPSXQVw39Ux7NXXUbEyuA07jYhVXON1J/qgl kL2RklPet9fjO0UTBE1TKxDepUdGECZHENUZ4q4Bo7uafSDxWY/V6b7AJm7zFZcA tTL7fYUiZbh9m7DzZZNLyVZXRt6BfMzPlgLjK8nEZXLbvF/n0zQ= =A/1r -----END PGP SIGNATURE----- --=-sL1rgkZbhhqGAClQPGna--