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Date: Tue, 13 Oct 2015 15:52:06 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Nikhil Rao <nikhil.rao@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Sudeep Dutt <sudeep.dutt@intel.com>, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org
Subject: [patch] misc: mic/scif: re-take a lock on error path
Message-ID: <20151013125206.GA2524@mwanda>
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The caller expects that we take this lock again before returning
otherwise it you get double unlocks and races.

Fixes: ba612aa8b487 ('misc: mic: SCIF memory registration and unregistration')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/misc/mic/scif/scif_rma.c b/drivers/misc/mic/scif/scif_rma.c
index e288996..980ef13 100644
--- a/drivers/misc/mic/scif/scif_rma.c
+++ b/drivers/misc/mic/scif/scif_rma.c
@@ -680,6 +680,7 @@ int scif_unregister_window(struct scif_window *window)
 			}
 		} else {
 			/* Return ENXIO since unregistration is in progress */
+			mutex_lock(&ep->rma_info.rma_lock);
 			return -ENXIO;
 		}
 retry: