[GIT pull] core/debugobjects for v6.4-rc1

[Thomas Gleixner]

Linus,

please pull the latest core/debugobjects branch from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core-debugobjects-2023-05-06

up to:  0af462f19e63: debugobject: Ensure pool refill (again)


A single fix for debugobjects:

  The recent fix to ensure atomicity of lookup and allocation inadvertently
  broke the pool refill mechanism, so that debugobject OOMs now in certain
  situations. The reason is that the functions which got updated no longer
  invoke debug_objecs_init(), which is now the only place to care about
  refilling the tracking object pool.

  Restore the original behaviour by adding explicit refill opportunities to
  those places.

Thanks,

	tglx

------------------>
Thomas Gleixner (1):
      debugobject: Ensure pool refill (again)


 lib/debugobjects.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index b796799fadb2..003edc5ebd67 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -587,6 +587,16 @@ static struct debug_obj *lookup_object_or_alloc(void *addr, struct debug_bucket
 	return NULL;
 }
 
+static void debug_objects_fill_pool(void)
+{
+	/*
+	 * On RT enabled kernels the pool refill must happen in preemptible
+	 * context:
+	 */
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT) || preemptible())
+		fill_pool();
+}
+
 static void
 __debug_object_init(void *addr, const struct debug_obj_descr *descr, int onstack)
 {
@@ -595,12 +605,7 @@ __debug_object_init(void *addr, const struct debug_obj_descr *descr, int onstack
 	struct debug_obj *obj;
 	unsigned long flags;
 
-	/*
-	 * On RT enabled kernels the pool refill must happen in preemptible
-	 * context:
-	 */
-	if (!IS_ENABLED(CONFIG_PREEMPT_RT) || preemptible())
-		fill_pool();
+	debug_objects_fill_pool();
 
 	db = get_bucket((unsigned long) addr);
 
@@ -685,6 +690,8 @@ int debug_object_activate(void *addr, const struct debug_obj_descr *descr)
 	if (!debug_objects_enabled)
 		return 0;
 
+	debug_objects_fill_pool();
+
 	db = get_bucket((unsigned long) addr);
 
 	raw_spin_lock_irqsave(&db->lock, flags);
@@ -894,6 +901,8 @@ void debug_object_assert_init(void *addr, const struct debug_obj_descr *descr)
 	if (!debug_objects_enabled)
 		return;
 
+	debug_objects_fill_pool();
+
 	db = get_bucket((unsigned long) addr);
 
 	raw_spin_lock_irqsave(&db->lock, flags);