unregister_blkdev(): do WARN_ON on failure

When unregister_blkdev() has failed, something wrong happened.  This patch
adds WARN_ON to notify of such badness.

Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/block/genhd.c b/block/genhd.c
index b321cadd6e65b5d543aed766ccdc09cad0be7eb0..7f71b2c472b836e8df9a6953e4f81058fa800793 100644 (file)
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -120,9 +120,10 @@ int unregister_blkdev(unsigned int major, const char *name)
        for (n = &major_names[index]; *n; n = &(*n)->next)
                if ((*n)->major == major)
                        break;
-       if (!*n || strcmp((*n)->name, name))
+       if (!*n || strcmp((*n)->name, name)) {
+               WARN_ON(1);
                ret = -EINVAL;
-       else {
+       } else {
                p = *n;
                *n = p->next;
        }