1 files changed, 12 insertions, 8 deletions

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index a8ef4c4b94be..ba2f5e710af1 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -312,6 +312,7 @@ static ssize_t store_enabled(struct netconsole_target *nt,
                              const char *buf,
                              size_t count)
 {
+        unsigned long flags;
         int enabled;
         int err;
 
@@ -326,9 +327,7 @@ static ssize_t store_enabled(struct netconsole_target *nt,
                 return -EINVAL;
         }
 
-        mutex_lock(&nt->mutex);
         if (enabled) {  /* 1 */
-
                 /*
                  * Skip netpoll_parse_options() -- all the attributes are
                  * already configured via configfs. Just print them out.
@@ -336,19 +335,22 @@ static ssize_t store_enabled(struct netconsole_target *nt,
                 netpoll_print_options(&nt->np);
 
                 err = netpoll_setup(&nt->np);
-                if (err) {
-                        mutex_unlock(&nt->mutex);
+                if (err)
                         return err;
-                }
-
-                pr_info("network logging started\n");
 
+                pr_info("netconsole: network logging started\n");
         } else {        /* 0 */
+                /* We need to disable the netconsole before cleaning it up
+                 * otherwise we might end up in write_msg() with
+                 * nt->np.dev == NULL and nt->enabled == 1
+                 */
+                spin_lock_irqsave(&target_list_lock, flags);
+                nt->enabled = 0;
+                spin_unlock_irqrestore(&target_list_lock, flags);
                 netpoll_cleanup(&nt->np);
         }
 
         nt->enabled = enabled;
-        mutex_unlock(&nt->mutex);
 
         return strnlen(buf, count);
 }
@@ -559,8 +561,10 @@ static ssize_t netconsole_target_attr_store(struct config_item *item,
         struct netconsole_target_attr *na =
                 container_of(attr, struct netconsole_target_attr, attr);
 
+        mutex_lock(&nt->mutex);
         if (na->store)
                 ret = na->store(nt, buf, count);
+        mutex_unlock(&nt->mutex);
 
         return ret;
 }