[PATCH -next] nullb: fix error return code in null_init()

[Wei Yongjun]

Fix to return error code -ENOMEM from the null_alloc_dev() error
handling case instead of 0, as done elsewhere in this function.

Fixes: 2984c8684f96 ("nullb: factor disk parameters")
Signed-off-by: Wei Yongjun <weiyongj...@huawei.com>
---
 drivers/block/null_blk.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index bf2c8ca..50c83c4 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -1991,8 +1991,10 @@ static int __init null_init(void)
 
        for (i = 0; i < nr_devices; i++) {
                dev = null_alloc_dev();
-               if (!dev)
+               if (!dev) {
+                       ret = -ENOMEM;
                        goto err_dev;
+               }
                ret = null_add_dev(dev);
                if (ret) {
                        null_free_dev(dev);