From:   George Prekas <george@enfabrica.net>
To:     linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        "Liam R. Howlett" <Liam.Howlett@Oracle.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Andrei Vagin <avagin@gmail.com>,
        George Prekas <george@enfabrica.net>
Subject: [PATCH 2/9] Revert "mm/kmemleak: make create_object return void"
Date:   Mon, 23 Jan 2023 11:04:12 -0600
Message-Id: <20230123170419.7292-3-george@enfabrica.net>
In-Reply-To: <20230123170419.7292-1-george@enfabrica.net>
References: <20230123170419.7292-1-george@enfabrica.net>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

This reverts commit b955aa70a3ac9f1dd5e26d4c7673ec3c28a8c2af.

The function delete_object_part can use the return value of
create_object to propagate flags from the old object to the new objects.

Signed-off-by: George Prekas <george@enfabrica.net>
---
 mm/kmemleak.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index b40735539abd..2b9c9ad68806 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -616,8 +616,9 @@ static noinline depot_stack_handle_t set_track_prepare(void)
  * memory block and add it to the object_list and object_tree_root (or
  * object_phys_tree_root).
  */
-static void __create_object(unsigned long ptr, size_t size,
-			    int min_count, gfp_t gfp, bool is_phys)
+static struct kmemleak_object *__create_object(unsigned long ptr, size_t size,
+					     int min_count, gfp_t gfp,
+					     bool is_phys)
 {
 	unsigned long flags;
 	struct kmemleak_object *object, *parent;
@@ -629,7 +630,7 @@ static void __create_object(unsigned long ptr, size_t size,
 	if (!object) {
 		pr_warn("Cannot allocate a kmemleak_object structure\n");
 		kmemleak_disable();
-		return;
+		return NULL;
 	}
 
 	INIT_LIST_HEAD(&object->object_list);
@@ -698,6 +699,7 @@ static void __create_object(unsigned long ptr, size_t size,
 			 */
 			dump_object_info(parent);
 			kmem_cache_free(object_cache, object);
+			object = NULL;
 			goto out;
 		}
 	}
@@ -707,20 +709,21 @@ static void __create_object(unsigned long ptr, size_t size,
 	list_add_tail_rcu(&object->object_list, &object_list);
 out:
 	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
+	return object;
 }
 
 /* Create kmemleak object which allocated with virtual address. */
-static void create_object(unsigned long ptr, size_t size,
-			  int min_count, gfp_t gfp)
+static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
+					     int min_count, gfp_t gfp)
 {
-	__create_object(ptr, size, min_count, gfp, false);
+	return __create_object(ptr, size, min_count, gfp, false);
 }
 
 /* Create kmemleak object which allocated with physical address. */
-static void create_object_phys(unsigned long ptr, size_t size,
-			       int min_count, gfp_t gfp)
+static struct kmemleak_object *create_object_phys(unsigned long ptr, size_t size,
+					     int min_count, gfp_t gfp)
 {
-	__create_object(ptr, size, min_count, gfp, true);
+	return __create_object(ptr, size, min_count, gfp, true);
 }
 
 /*
-- 
2.37.1