From: Chaitanya Kulkarni <kch@nvidia.com>
Date: Tue, 15 Feb 2022 03:59:51 -0800
Subject: [PATCH] null_blk: fix return value from null_add_dev()
Git-commit: a75110c3b36959d04d3a586ba43510ddf9b410b5
Patch-mainline: v5.18-rc1
References: jsc#PED-1183

The function nullb_device_power_store() returns -ENOMEM when
null_add_dev() fails. null_add_dev() can fail with return value
other than -ENOMEM such as -EINVAL when Zoned Block Device option
is used, see :

nullb_device_power_store()
 null_add_dev()
  null_init_zoned_dev()
	return -EINVAL;

When trying to load the module having -ENOMEM value returned on the
command line creates confusion when pleanty of memory is free on the
machine.

Instead of hardcoding -ENOMEM return the value of null_add_dev()
function.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220215115951.15945-1-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/block/null_blk/main.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 13004beb48ca..90b6bd2a114b 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -431,9 +431,10 @@ static ssize_t nullb_device_power_store(struct config_item *item,
 	if (!dev->power && newp) {
 		if (test_and_set_bit(NULLB_DEV_FL_UP, &dev->flags))
 			return count;
-		if (null_add_dev(dev)) {
+		ret = null_add_dev(dev);
+		if (ret) {
 			clear_bit(NULLB_DEV_FL_UP, &dev->flags);
-			return -ENOMEM;
+			return ret;
 		}
 
 		set_bit(NULLB_DEV_FL_CONFIGURED, &dev->flags);
-- 
2.35.3