Fix segfault with client/server and minimal output

Fixes: bf2921f02651
Reported-by: Ben England <bengland@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/diskutil.c b/diskutil.c
index 98ae2fe302008bf0c2b10cd55cb80c0a2b7327ae..52d87f6433d85132b2ae2fd3e6bfdc127fc64393 100644 (file)
--- a/diskutil.c
+++ b/diskutil.c
@@ -694,6 +694,9 @@ void show_disk_util(int terse, struct json_object *parent)
        struct flist_head *entry;
        struct disk_util *du;
 
+       if (!disk_util_mutex)
+               return;
+
        fio_mutex_down(disk_util_mutex);
 
        if (flist_empty(&disk_list)) {