From mboxrd@z Thu Jan 1 00:00:00 1970 From: Uma Krishnan Subject: [PATCH 2/3] cxlflash: Avoid double mutex unlock Date: Fri, 25 Aug 2017 17:18:03 -0500 Message-ID: <1503699483-61541-1-git-send-email-ukrishn@linux.vnet.ibm.com> References: <1503699440-61464-1-git-send-email-ukrishn@linux.vnet.ibm.com> Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:52033 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933883AbdHYWSL (ORCPT ); Fri, 25 Aug 2017 18:18:11 -0400 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7PMGufw046966 for ; Fri, 25 Aug 2017 18:18:11 -0400 Received: from e14.ny.us.ibm.com (e14.ny.us.ibm.com [129.33.205.204]) by mx0a-001b2d01.pphosted.com with ESMTP id 2cjsrsqsxy-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 25 Aug 2017 18:18:11 -0400 Received: from localhost by e14.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 25 Aug 2017 18:18:10 -0400 In-Reply-To: <1503699440-61464-1-git-send-email-ukrishn@linux.vnet.ibm.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org, James Bottomley , "Martin K. Petersen" , "Matthew R. Ochs" , "Manoj N. Kumar" Cc: linuxppc-dev@lists.ozlabs.org, Andrew Donnellan , Frederic Barrat , Christophe Lombard From: "Matthew R. Ochs" The AFU recovery routine uses an interruptible mutex to control the flow of in-flight recoveries. Upon receiving an interruptible signal the code branches to a common exit path which wrongly assumes the mutex is held. Add a local variable to track when the mutex should be unlocked. Signed-off-by: Matthew R. Ochs Signed-off-by: Uma Krishnan --- drivers/scsi/cxlflash/superpipe.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c index ad0f996..e9ee1d9 100644 --- a/drivers/scsi/cxlflash/superpipe.c +++ b/drivers/scsi/cxlflash/superpipe.c @@ -1650,6 +1650,7 @@ static int cxlflash_afu_recover(struct scsi_device *sdev, u64 ctxid = DECODE_CTXID(recover->context_id), rctxid = recover->context_id; long reg; + bool locked = true; int lretry = 20; /* up to 2 seconds */ int new_adap_fd = -1; int rc = 0; @@ -1658,8 +1659,11 @@ static int cxlflash_afu_recover(struct scsi_device *sdev, up_read(&cfg->ioctl_rwsem); rc = mutex_lock_interruptible(mutex); down_read(&cfg->ioctl_rwsem); - if (rc) + if (rc) { + locked = false; goto out; + } + rc = check_state(cfg); if (rc) { dev_err(dev, "%s: Failed state rc=%d\n", __func__, rc); @@ -1693,8 +1697,10 @@ static int cxlflash_afu_recover(struct scsi_device *sdev, mutex_unlock(mutex); msleep(100); rc = mutex_lock_interruptible(mutex); - if (rc) + if (rc) { + locked = false; goto out; + } goto retry_recover; } @@ -1738,7 +1744,8 @@ static int cxlflash_afu_recover(struct scsi_device *sdev, out: if (likely(ctxi)) put_context(ctxi); - mutex_unlock(mutex); + if (locked) + mutex_unlock(mutex); atomic_dec_if_positive(&cfg->recovery_threads); return rc; } -- 2.1.0