[RFC PATCH v1.1 01/11] mm/damon/sysfs: kobject_del() target (normal), context and kdamond dirs

[SeongJae Park <sj@kernel.org>]

On CONFIG_DEBUG_KOBJECT_RELEASE enabled kernel, lack of kobject_del()
could cause directories creation failures due to the name conflicts. Fix
those issues for normal creation paths of target, context and kdamond
directories, and error paths of context and kdamond directories by
adding kobject_del() calls.

Note that this fix for target directories is not complete since it has a
similar issue in the damon_sysfs_targets_add_dirs() error path.  Because
the normal path issue and the error path issue are introduced by
different commits, this commit is fixing only the normal path issue.  A
commit for the error path will be added next.

Fixes: c951cd3b8901 ("mm/damon: implement a minimal stub for sysfs-based DAMON interface")
Cc: <stable@vger.kernel.org> # 5.18.x
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 2e95e3bac774d..dba1c67fc188f 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -333,6 +333,7 @@ static void damon_sysfs_targets_rm_dirs(struct damon_sysfs_targets *targets)
 
 	for (i = 0; i < targets->nr; i++) {
 		damon_sysfs_target_rm_dirs(targets_arr[i]);
+		kobject_del(&targets_arr[i]->kobj);
 		kobject_put(&targets_arr[i]->kobj);
 	}
 	targets->nr = 0;
@@ -1642,6 +1643,7 @@ static void damon_sysfs_contexts_rm_dirs(struct damon_sysfs_contexts *contexts)
 
 	for (i = 0; i < contexts->nr; i++) {
 		damon_sysfs_context_rm_dirs(contexts_arr[i]);
+		kobject_del(&contexts_arr[i]->kobj);
 		kobject_put(&contexts_arr[i]->kobj);
 	}
 	contexts->nr = 0;
@@ -1680,13 +1682,15 @@ static int damon_sysfs_contexts_add_dirs(struct damon_sysfs_contexts *contexts,
 
 		err = damon_sysfs_context_add_dirs(context);
 		if (err)
-			goto out;
+			goto del_out;
 
 		contexts_arr[i] = context;
 		contexts->nr++;
 	}
 	return 0;
 
+del_out:
+	kobject_del(&context->kobj);
 out:
 	damon_sysfs_contexts_rm_dirs(contexts);
 	kobject_put(&context->kobj);
@@ -2501,6 +2505,7 @@ static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds)
 
 	for (i = 0; i < kdamonds->nr; i++) {
 		damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]);
+		kobject_del(&kdamonds_arr[i]->kobj);
 		kobject_put(&kdamonds_arr[i]->kobj);
 	}
 	kdamonds->nr = 0;
@@ -2555,13 +2560,15 @@ static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds,
 
 		err = damon_sysfs_kdamond_add_dirs(kdamond);
 		if (err)
-			goto out;
+			goto del_out;
 
 		kdamonds_arr[i] = kdamond;
 		kdamonds->nr++;
 	}
 	return 0;
 
+del_out:
+	kobject_del(&kdamond->kobj);
 out:
 	damon_sysfs_kdamonds_rm_dirs(kdamonds);
 	kobject_put(&kdamond->kobj);
-- 
2.47.3