The patch below was submitted to be applied to the 4.18-stable tree.
I fail to see how this patch meets the stable kernel rules as found at
Documentation/process/stable-kernel-rules.rst.
I could be totally wrong, and if so, please respond to
<stable@xxxxxxxxxxxxxxx> and let me know why this patch should be
applied. Otherwise, it is now dropped from my patch queues, never to be
seen again.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 78ac2107176baa0daf65b0fb8e561d2ed14c83ca Mon Sep 17 00:00:00 2001
From: Coly Li <colyli@xxxxxxx>
Date: Thu, 9 Aug 2018 15:48:42 +0800
Subject: [PATCH] bcache: do not check return value of debugfs_create_dir()
Greg KH suggests that normal code should not care about debugfs. Therefore
no matter successful or failed of debugfs_create_dir() execution, it is
unncessary to check its return value.
There are two functions called debugfs_create_dir() and check the return
value, which are bch_debug_init() and closure_debug_init(). This patch
changes these two functions from int to void type, and ignore return values
of debugfs_create_dir().
This patch does not fix exact bug, just makes things work as they should.
Signed-off-by: Coly Li <colyli@xxxxxxx>
Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: Kai Krakow <kai@xxxxxxxxxxx>
Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 872ef4d67711..0a3e82b0876d 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -1001,7 +1001,7 @@ void bch_open_buckets_free(struct cache_set *);
int bch_cache_allocator_start(struct cache *ca);
void bch_debug_exit(void);
-int bch_debug_init(struct kobject *);
+void bch_debug_init(struct kobject *kobj);
void bch_request_exit(void);
int bch_request_init(void);
diff --git a/drivers/md/bcache/closure.c b/drivers/md/bcache/closure.c
index 0e14969182c6..618253683d40 100644
--- a/drivers/md/bcache/closure.c
+++ b/drivers/md/bcache/closure.c
@@ -199,11 +199,16 @@ static const struct file_operations debug_ops = {
.release = single_release
};
-int __init closure_debug_init(void)
+void __init closure_debug_init(void)
{
- closure_debug = debugfs_create_file("closures",
- 0400, bcache_debug, NULL, &debug_ops);
- return IS_ERR_OR_NULL(closure_debug);
+ if (!IS_ERR_OR_NULL(bcache_debug))
+ /*
+ * it is unnecessary to check return value of
+ * debugfs_create_file(), we should not care
+ * about this.
+ */
+ closure_debug = debugfs_create_file(
+ "closures", 0400, bcache_debug, NULL, &debug_ops);
}
#endif
diff --git a/drivers/md/bcache/closure.h b/drivers/md/bcache/closure.h
index 71427eb5fdae..7c2c5bc7c88b 100644
--- a/drivers/md/bcache/closure.h
+++ b/drivers/md/bcache/closure.h
@@ -186,13 +186,13 @@ static inline void closure_sync(struct closure *cl)
#ifdef CONFIG_BCACHE_CLOSURES_DEBUG
-int closure_debug_init(void);
+void closure_debug_init(void);
void closure_debug_create(struct closure *cl);
void closure_debug_destroy(struct closure *cl);
#else
-static inline int closure_debug_init(void) { return 0; }
+static inline void closure_debug_init(void) {}
static inline void closure_debug_create(struct closure *cl) {}
static inline void closure_debug_destroy(struct closure *cl) {}
diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
index 04d146711950..12034c07257b 100644
--- a/drivers/md/bcache/debug.c
+++ b/drivers/md/bcache/debug.c
@@ -252,11 +252,12 @@ void bch_debug_exit(void)
debugfs_remove_recursive(bcache_debug);
}
-int __init bch_debug_init(struct kobject *kobj)
+void __init bch_debug_init(struct kobject *kobj)
{
- if (!IS_ENABLED(CONFIG_DEBUG_FS))
- return 0;
-
+ /*
+ * it is unnecessary to check return value of
+ * debugfs_create_file(), we should not care
+ * about this.
+ */
bcache_debug = debugfs_create_dir("bcache", NULL);
- return IS_ERR_OR_NULL(bcache_debug);
}
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index e0a92104ca23..c7ffa6ef3f82 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -2345,10 +2345,12 @@ static int __init bcache_init(void)
goto err;
if (bch_request_init() ||
- bch_debug_init(bcache_kobj) || closure_debug_init() ||
sysfs_create_files(bcache_kobj, files))
goto err;
+ bch_debug_init(bcache_kobj);
+ closure_debug_init();
+
return 0;
err:
bcache_exit();
