Merge tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-block

[sfrench/cifs-2.6.git] / kernel / trace / blktrace.c

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 2a24a59e99c569bebca133151fb66a4922dabd86..2868d85f1fb1d3286984c4727f0519957ac069a9 100644 (file)
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -1829,6 +1829,10 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
        mutex_lock(&q->blk_trace_mutex);
 
        if (attr == &dev_attr_enable) {
+               if (!!value == !!q->blk_trace) {
+                       ret = 0;
+                       goto out_unlock_bdev;
+               }
                if (value)
                        ret = blk_trace_setup_queue(q, bdev);
                else