From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: [PATCH] ibmvfc: Fix a locking imbalance Date: Wed, 4 Mar 2015 11:03:10 +0100 Message-ID: <54F6D85E.5060906@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-bn1bon0093.outbound.protection.outlook.com ([157.56.111.93]:61360 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932828AbbCDKDS (ORCPT ); Wed, 4 Mar 2015 05:03:18 -0500 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: Brian King , Nathan Fontenot , Tyrel Datwyler , "linux-scsi@vger.kernel.org" Avoid that the spin_lock() statement after kref_put() triggers a lockup if rport != NULL && get_device() == 0. Detected by sparse. Compile-tested only. Signed-off-by: Bart Van Assche Cc: Brian King Cc: Nathan Fontenot Cc: Tyrel Datwyler --- drivers/scsi/ibmvscsi/ibmvfc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c index 057d277..b46257a 100644 --- a/drivers/scsi/ibmvscsi/ibmvfc.c +++ b/drivers/scsi/ibmvscsi/ibmvfc.c @@ -4722,6 +4722,8 @@ static void ibmvfc_rport_add_thread(struct work_struct *work) tgt_dbg(tgt, "Setting rport roles\n"); fc_remote_port_rolechg(rport, tgt->ids.roles); put_device(&rport->dev); + } else { + spin_unlock_irqrestore(vhost->host->host_lock, flags); } kref_put(&tgt->kref, ibmvfc_release_tgt); -- 2.1.4