The patch below does not apply to the 4.16-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 1c1a2ee1b53b006754073eefc65d2b2cedb5264b Mon Sep 17 00:00:00 2001
From: Coly Li <colyli@xxxxxxx>
Date: Thu, 17 May 2018 23:33:26 +0800
Subject: [PATCH] bcache: return 0 from bch_debug_init() if CONFIG_DEBUG_FS=n
Commit 539d39eb2708 ("bcache: fix wrong return value in bch_debug_init()")
returns the return value of debugfs_create_dir() to bcache_init(). When
CONFIG_DEBUG_FS=n, bch_debug_init() always returns 1 and makes
bcache_init() failedi.
This patch makes bch_debug_init() always returns 0 if CONFIG_DEBUG_FS=n,
so bcache can continue to work for the kernels which don't have debugfs
enanbled.
Changelog:
v4: Add Acked-by from Kent Overstreet.
v3: Use IS_ENABLED(CONFIG_DEBUG_FS) to replace #ifdef DEBUG_FS.
v2: Remove a warning information
v1: Initial version.
Fixes: Commit 539d39eb2708 ("bcache: fix wrong return value in bch_debug_init()")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Coly Li <colyli@xxxxxxx>
Reported-by: Massimo B. <massimo.b@xxxxxxx>
Reported-by: Kai Krakow <kai@xxxxxxxxxxx>
Tested-by: Kai Krakow <kai@xxxxxxxxxxx>
Acked-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
index 4e63c6f6c04d..d030ce3025a6 100644
--- a/drivers/md/bcache/debug.c
+++ b/drivers/md/bcache/debug.c
@@ -250,7 +250,9 @@ void bch_debug_exit(void)
int __init bch_debug_init(struct kobject *kobj)
{
- bcache_debug = debugfs_create_dir("bcache", NULL);
+ if (!IS_ENABLED(CONFIG_DEBUG_FS))
+ return 0;
+ bcache_debug = debugfs_create_dir("bcache", NULL);
return IS_ERR_OR_NULL(bcache_debug);
}
