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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 A715FC04AB6 for ; Tue, 28 May 2019 23:29:29 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 E9B0720B1F for ; Tue, 28 May 2019 23:29:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E9B0720B1F 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=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45D96G25WmzDqQh for ; Wed, 29 May 2019 09:29:26 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=nathanl@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45D94q2f7zzDqHp for ; Wed, 29 May 2019 09:28:10 +1000 (AEST) Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x4SNMOog143435 for ; Tue, 28 May 2019 19:28:05 -0400 Received: from e32.co.us.ibm.com (e32.co.us.ibm.com [32.97.110.150]) by mx0b-001b2d01.pphosted.com with ESMTP id 2ssdqm9tq5-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 28 May 2019 19:28:05 -0400 Received: from localhost by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Wed, 29 May 2019 00:28:02 +0100 Received: from b03ledav001.gho.boulder.ibm.com (b03ledav001.gho.boulder.ibm.com [9.17.130.232]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x4SNS1w913959676 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Tue, 28 May 2019 23:28:01 GMT Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C7CA16E054 for ; Tue, 28 May 2019 23:28:01 +0000 (GMT) Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AF0DF6E050 for ; Tue, 28 May 2019 23:28:01 +0000 (GMT) Received: from localhost (unknown [9.41.179.236]) by b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTP for ; Tue, 28 May 2019 23:28:01 +0000 (GMT) From: Nathan Lynch To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH] powerpc/pseries: avoid blocking in irq when queuing hotplug events Date: Tue, 28 May 2019 18:28:01 -0500 X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19052823-0004-0000-0000-000015155D19 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00011176; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000286; SDB=6.01210002; UDB=6.00635683; IPR=6.00991031; MB=3.00027092; MTD=3.00000008; XFM=3.00000015; UTC=2019-05-28 23:28:04 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19052823-0005-0000-0000-00008BD7E85E Message-Id: <20190528232801.7413-1-nathanl@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-05-28_11:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 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=8.0.1-1810050000 definitions=main-1905280147 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" A couple of bugs in queue_hotplug_event(): 1. Unchecked kmalloc result which could lead to an oops. 2. Use of GFP_KERNEL allocations in interrupt context (this code's only caller is ras_hotplug_interrupt()). Use kmemdup to avoid open-coding the allocation+copy and check for failure; use GFP_ATOMIC for both allocations. Ultimately it probably would be better to avoid or reduce allocations in this path if possible. Signed-off-by: Nathan Lynch --- Found by inspection, built but not runtime-tested. arch/powerpc/platforms/pseries/dlpar.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c index 17958043e7f7..d70f9b925378 100644 --- a/arch/powerpc/platforms/pseries/dlpar.c +++ b/arch/powerpc/platforms/pseries/dlpar.c @@ -386,11 +386,11 @@ void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog) struct pseries_hp_work *work; struct pseries_hp_errorlog *hp_errlog_copy; - hp_errlog_copy = kmalloc(sizeof(struct pseries_hp_errorlog), - GFP_KERNEL); - memcpy(hp_errlog_copy, hp_errlog, sizeof(struct pseries_hp_errorlog)); + hp_errlog_copy = kmemdup(hp_errlog, sizeof(*hp_errlog), GFP_ATOMIC); + if (!hp_errlog_copy) + return; - work = kmalloc(sizeof(struct pseries_hp_work), GFP_KERNEL); + work = kmalloc(sizeof(struct pseries_hp_work), GFP_ATOMIC); if (work) { INIT_WORK((struct work_struct *)work, pseries_hp_work_fn); work->errlog = hp_errlog_copy; -- 2.20.1