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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 2A051C4CECC for ; Mon, 16 Sep 2019 09:57:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D2094206A4 for ; Mon, 16 Sep 2019 09:57:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D2094206A4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 422866B0005; Mon, 16 Sep 2019 05:57:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3D3996B0006; Mon, 16 Sep 2019 05:57:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2E9576B0007; Mon, 16 Sep 2019 05:57:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0091.hostedemail.com [216.40.44.91]) by kanga.kvack.org (Postfix) with ESMTP id 0EC7F6B0005 for ; Mon, 16 Sep 2019 05:57:26 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id AC0F0824CA2F for ; Mon, 16 Sep 2019 09:57:25 +0000 (UTC) X-FDA: 75940331250.26.honey23_7af94fe116f55 X-HE-Tag: honey23_7af94fe116f55 X-Filterd-Recvd-Size: 5551 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by imf23.hostedemail.com (Postfix) with ESMTP for ; Mon, 16 Sep 2019 09:57:24 +0000 (UTC) Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8G9qTcD137685 for ; Mon, 16 Sep 2019 05:57:23 -0400 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v0uusm5s7-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 16 Sep 2019 05:57:23 -0400 Received: from localhost by e06smtp02.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 16 Sep 2019 10:57:20 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (9.149.109.195) by e06smtp02.uk.ibm.com (192.168.101.132) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 16 Sep 2019 10:57:18 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8G9vHJW50397298 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 16 Sep 2019 09:57:17 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EC8844C046; Mon, 16 Sep 2019 09:57:16 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E09854C040; Mon, 16 Sep 2019 09:57:14 +0000 (GMT) Received: from pomme.com (unknown [9.145.76.175]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 16 Sep 2019 09:57:14 +0000 (GMT) From: Laurent Dufour To: mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org, aneesh.kumar@linux.ibm.com, npiggin@gmail.com, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 0/2] powerpc/mm: Conditionally call H_BLOCK_REMOVE Date: Mon, 16 Sep 2019 11:55:41 +0200 X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 X-TM-AS-GCONF: 00 x-cbid: 19091609-0008-0000-0000-00000316E1D3 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19091609-0009-0000-0000-00004A355A78 Message-Id: <20190916095543.17496-1-ldufour@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-16_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909160105 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Since the commit ba2dd8a26baa ("powerpc/pseries/mm: call H_BLOCK_REMOVE")= , the call to H_BLOCK_REMOVE is always done if the feature is exhibited. However, the hypervisor may not support all the block size for the hcall H_BLOCK_REMOVE depending on the segment base page size and actual page size. When unsupported block size is used, the hcall H_BLOCK_REMOVE is returnin= g H_PARAM, which is triggering a BUG_ON check leading to a panic like this: The PAPR document specifies the TLB Block Invalidate Characteristics whic= h tells for each couple segment base page size, actual page size, the size = of the block the hcall H_BLOCK_REMOVE is supporting. Supporting various block sizes doesn't seem needed at that time since all systems I was able to play with was supporting an 8 addresses block size, which is the maximum through the hcall, or none at all. Supporting variou= s size would complexify the algorithm in call_block_remove() so unless this is required, this is not done. In the case of block size different from 8, a warning message is displaye= d at boot time and that block size will be ignored checking for the H_BLOCK_REMOVE support. Due to the minimal amount of hardware showing a limited set of H_BLOCK_REMOVE supported page size, I don't think there is a need to push this series to the stable mailing list. The first patch is reading the characteristic through the hcall ibm,get-system-parameter and record the supported block size for each pag= e size. The second patch is changing the check used to detect the H_BLOCK_REMOVE availability to take care of the base page size and page size couple. Changes since V1: - Remove penc initialisation, this is already done in mmu_psize_set_default_penc() - Add details on the TLB Block Invalidate Characteristics's buffer forma= t - Introduce #define instead of using direct numerical values - Function reading the characteristics is now directly called from pSeries_setup_arch() - The characteristics are now stored in a dedciated table static to lpar= .c Laurent Dufour (2): powperc/mm: read TLB Block Invalidate Characteristics powerpc/mm: call H_BLOCK_REMOVE when supported .../include/asm/book3s/64/tlbflush-hash.h | 1 + arch/powerpc/platforms/pseries/lpar.c | 173 +++++++++++++++++- arch/powerpc/platforms/pseries/setup.c | 1 + 3 files changed, 173 insertions(+), 2 deletions(-) --=20 2.23.0