From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933905AbeBLKVb (ORCPT ); Mon, 12 Feb 2018 05:21:31 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:34248 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932868AbeBLKV2 (ORCPT ); Mon, 12 Feb 2018 05:21:28 -0500 From: Shilpasri G Bhat To: rjw@rjwysocki.net Cc: linux-pm@vger.kernel.org, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au, Shilpasri G Bhat Subject: [PATCH] cpufreq: powernv: Check negative value returned by cpufreq_table_find_index_dl() Date: Mon, 12 Feb 2018 15:51:16 +0530 X-Mailer: git-send-email 1.8.3.1 X-TM-AS-GCONF: 00 x-cbid: 18021210-0040-0000-0000-0000040ECC8C X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18021210-0041-0000-0000-000026128AB1 Message-Id: <1518430876-24464-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2018-02-12_05:,, 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=1011 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1802120134 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch fixes the below Coverity warning: *** CID 182816: Memory - illegal accesses (NEGATIVE_RETURNS) /drivers/cpufreq/powernv-cpufreq.c: 1008 in powernv_fast_switch() 1002 unsigned int target_freq) 1003 { 1004 int index; 1005 struct powernv_smp_call_data freq_data; 1006 1007 index = cpufreq_table_find_index_dl(policy, target_freq); >>> CID 182816: Memory - illegal accesses (NEGATIVE_RETURNS) >>> Using variable "index" as an index to array "powernv_freqs". 1008 freq_data.pstate_id = powernv_freqs[index].driver_data; 1009 freq_data.gpstate_id = powernv_freqs[index].driver_data; 1010 set_pstate(&freq_data); 1011 1012 return powernv_freqs[index].frequency; 1013 } Signed-off-by: Shilpasri G Bhat --- drivers/cpufreq/powernv-cpufreq.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 29cdec1..69edfe9 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -1005,6 +1005,9 @@ static unsigned int powernv_fast_switch(struct cpufreq_policy *policy, struct powernv_smp_call_data freq_data; index = cpufreq_table_find_index_dl(policy, target_freq); + if (unlikely(index < 0)) + index = get_nominal_index(); + freq_data.pstate_id = powernv_freqs[index].driver_data; freq_data.gpstate_id = powernv_freqs[index].driver_data; set_pstate(&freq_data); -- 1.8.3.1