[PATCH 5.4 16/37] cryptoloop: add a deprecation warning

From: Greg Kroah-Hartman
Date: Fri Sep 10 2021 - 08:35:53 EST

From: Christoph Hellwig <hch@xxxxxx>

[ Upstream commit 222013f9ac30b9cec44301daa8dbd0aae38abffb ]

Support for cryptoloop has been officially marked broken and deprecated
in favor of dm-crypt (which supports the same broken algorithms if
needed) in Linux 2.6.4 (released in March 2004), and support for it has
been entirely removed from losetup in util-linux 2.23 (released in April
2013). Add a warning and a deprecation schedule.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Link: https://lore.kernel.org/r/20210827163250.255325-1-hch@xxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/block/Kconfig | 4 ++--
drivers/block/cryptoloop.c | 2 ++
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 0fc27ac14f29..9f6782329a23 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -230,7 +230,7 @@ config BLK_DEV_LOOP_MIN_COUNT
dynamically allocated with the /dev/loop-control interface.

- tristate "Cryptoloop Support"
+ tristate "Cryptoloop Support (DEPRECATED)"
select CRYPTO
depends on BLK_DEV_LOOP
@@ -242,7 +242,7 @@ config BLK_DEV_CRYPTOLOOP
WARNING: This device is not safe for journaled file systems like
ext3 or Reiserfs. Please use the Device Mapper crypto module
instead, which can be configured to be on-disk compatible with the
- cryptoloop device.
+ cryptoloop device. cryptoloop support will be removed in Linux 5.16.

source "drivers/block/drbd/Kconfig"

diff --git a/drivers/block/cryptoloop.c b/drivers/block/cryptoloop.c
index 3cabc335ae74..f0a91faa43a8 100644
--- a/drivers/block/cryptoloop.c
+++ b/drivers/block/cryptoloop.c
@@ -189,6 +189,8 @@ init_cryptoloop(void)

if (rc)
printk(KERN_ERR "cryptoloop: loop_register_transfer failed\n");
+ else
+ pr_warn("the cryptoloop driver has been deprecated and will be removed in in Linux 5.16\n");
return rc;