From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 3sHkwM64BwzDrJq for ; Mon, 22 Aug 2016 17:00:02 +1000 (AEST) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u7M6wNCr022256 for ; Mon, 22 Aug 2016 03:00:00 -0400 Received: from e28smtp03.in.ibm.com (e28smtp03.in.ibm.com [125.16.236.3]) by mx0a-001b2d01.pphosted.com with ESMTP id 24xy4wbujs-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 22 Aug 2016 03:00:00 -0400 Received: from localhost by e28smtp03.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 22 Aug 2016 12:29:57 +0530 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id 8E01E1258083 for ; Mon, 22 Aug 2016 12:33:09 +0530 (IST) Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay04.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u7M6vnbi24707432 for ; Mon, 22 Aug 2016 12:27:49 +0530 Received: from d28av05.in.ibm.com (localhost [127.0.0.1]) by d28av05.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u7M6uger000317 for ; Mon, 22 Aug 2016 12:29:51 +0530 From: Mukesh Ojha To: hegdevasant@linux.vnet.ibm.com, mahesh@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org Cc: Mukesh Ojha , stable@vger.kernel.org Subject: [PATCH] powerpc/powernv : Drop reference added by kset_find_obj() Date: Mon, 22 Aug 2016 12:17:44 +0530 Message-Id: <1471848464-5735-1-git-send-email-mukesh02@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , In a situation, where Linux kernel gets notified about duplicate error log from OPAL, it is been observed that kernel fails to remove sysfs entries (/sys/firmware/opal/elog/0xXXXXXXXX) of such error logs. This is because, we currently search the error log/dump kobject in the kset list via 'kset_find_obj()' routine. Which eventually increment the reference count by one, once it founds the kobject. So, unless we decrement the reference count by one after it found the kobject, we would not be able to release the kobject properly later. This patch adds the 'kobject_put()' which was missing earlier. Signed-off-by: Mukesh Ojha Cc: stable@vger.kernel.org --- arch/powerpc/platforms/powernv/opal-dump.c | 7 ++++++- arch/powerpc/platforms/powernv/opal-elog.c | 7 ++++++- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/powernv/opal-dump.c b/arch/powerpc/platforms/powernv/opal-dump.c index 2ee9643..4c82782 100644 --- a/arch/powerpc/platforms/powernv/opal-dump.c +++ b/arch/powerpc/platforms/powernv/opal-dump.c @@ -370,6 +370,7 @@ static irqreturn_t process_dump(int irq, void *data) uint32_t dump_id, dump_size, dump_type; struct dump_obj *dump; char name[22]; + struct kobject *kobj; rc = dump_read_info(&dump_id, &dump_size, &dump_type); if (rc != OPAL_SUCCESS) @@ -381,8 +382,12 @@ static irqreturn_t process_dump(int irq, void *data) * that gracefully and not create two conflicting * entries. */ - if (kset_find_obj(dump_kset, name)) + kobj = kset_find_obj(dump_kset, name); + if (kobj) { + /* Drop reference added by kset_find_obj() */ + kobject_put(kobj); return 0; + } dump = create_dump_obj(dump_id, dump_size, dump_type); if (!dump) diff --git a/arch/powerpc/platforms/powernv/opal-elog.c b/arch/powerpc/platforms/powernv/opal-elog.c index 37f959b..f2344cb 100644 --- a/arch/powerpc/platforms/powernv/opal-elog.c +++ b/arch/powerpc/platforms/powernv/opal-elog.c @@ -247,6 +247,7 @@ static irqreturn_t elog_event(int irq, void *data) uint64_t elog_type; int rc; char name[2+16+1]; + struct kobject *kobj; rc = opal_get_elog_size(&id, &size, &type); if (rc != OPAL_SUCCESS) { @@ -269,8 +270,12 @@ static irqreturn_t elog_event(int irq, void *data) * that gracefully and not create two conflicting * entries. */ - if (kset_find_obj(elog_kset, name)) + kobj = kset_find_obj(elog_kset, name); + if (kobj) { + /* Drop reference added by kset_find_obj() */ + kobject_put(kobj); return IRQ_HANDLED; + } create_elog_obj(log_id, elog_size, elog_type); -- 2.7.4