watchdog: Fix race condition in registration code

[karo-tx-linux.git] / drivers / watchdog / watchdog_dev.c

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 08b48bbf9f4b2d3c65cf18045ff90c1465c9787f..faf4e189fe423179cb0261e77a3519a2a2b1c03e 100644 (file)
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -523,6 +523,7 @@ int watchdog_dev_register(struct watchdog_device *watchdog)
        int err, devno;
 
        if (watchdog->id == 0) {
+               old_wdd = watchdog;
                watchdog_miscdev.parent = watchdog->parent;
                err = misc_register(&watchdog_miscdev);
                if (err != 0) {
@@ -531,9 +532,9 @@ int watchdog_dev_register(struct watchdog_device *watchdog)
                        if (err == -EBUSY)
                                pr_err("%s: a legacy watchdog module is probably present.\n",
                                        watchdog->info->identity);
+                       old_wdd = NULL;
                        return err;
                }
-               old_wdd = watchdog;
        }
 
        /* Fill in the data structures */