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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 DA879C31E44 for ; Mon, 17 Jun 2019 08:41:13 +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 12A062080A for ; Mon, 17 Jun 2019 08:41:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 12A062080A 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 45S4S628DjzDqVT for ; Mon, 17 Jun 2019 18:41:10 +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=ravi.bangoria@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 45S4PL0fgdzDqC9 for ; Mon, 17 Jun 2019 18:38:45 +1000 (AEST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x5H8c1h4145600 for ; Mon, 17 Jun 2019 04:38:41 -0400 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0b-001b2d01.pphosted.com with ESMTP id 2t6708s95x-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 17 Jun 2019 04:38:40 -0400 Received: from localhost by e06smtp02.uk.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) Mon, 17 Jun 2019 09:38:35 +0100 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x5H8cY5M49283138 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 17 Jun 2019 08:38:35 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CEA8611C05C; Mon, 17 Jun 2019 08:38:34 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3B95611C04C; Mon, 17 Jun 2019 08:38:33 +0000 (GMT) Received: from [9.124.31.76] (unknown [9.124.31.76]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 17 Jun 2019 08:38:33 +0000 (GMT) Subject: Re: [PATCH v2] perf ioctl: Add check for the sample_period value To: mpe@ellerman.id.au, peterz@infradead.org References: <87h89eq55e.fsf@concordia.ellerman.id.au> <20190604042953.914-1-ravi.bangoria@linux.ibm.com> From: Ravi Bangoria Date: Mon, 17 Jun 2019 14:08:32 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190604042953.914-1-ravi.bangoria@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19061708-0008-0000-0000-000002F463F1 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19061708-0009-0000-0000-000022617484 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-06-17_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=8.0.1-1810050000 definitions=main-1906170081 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: , Cc: Ravi Bangoria , maddy@linux.vnet.ibm.com, jolsa@redhat.com, linux-kernel@vger.kernel.org, acme@kernel.org, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Peter / mpe, Is the v2 looks good? If so, can anyone of you please pick this up. On 6/4/19 9:59 AM, Ravi Bangoria wrote: > perf_event_open() limits the sample_period to 63 bits. See > commit 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period > to 63 bits"). Make ioctl() consistent with it. > > Also on powerpc, negative sample_period could cause a recursive > PMIs leading to a hang (reported when running perf-fuzzer). > > Signed-off-by: Ravi Bangoria > --- > kernel/events/core.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/kernel/events/core.c b/kernel/events/core.c > index abbd4b3b96c2..e44c90378940 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -5005,6 +5005,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) > if (perf_event_check_period(event, value)) > return -EINVAL; > > + if (!event->attr.freq && (value & (1ULL << 63))) > + return -EINVAL; > + > event_function_call(event, __perf_event_period, &value); > > return 0; >