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-rw-r--r--kernel/exit.c31
1 files changed, 15 insertions, 16 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 20a406471525..f2b321bae440 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -561,29 +561,28 @@ void exit_files(struct task_struct *tsk)
#ifdef CONFIG_MM_OWNER
/*
- * Task p is exiting and it owned mm, lets find a new owner for it
+ * A task is exiting. If it owned this mm, find a new owner for the mm.
*/
-static inline int
-mm_need_new_owner(struct mm_struct *mm, struct task_struct *p)
-{
- /*
- * If there are other users of the mm and the owner (us) is exiting
- * we need to find a new owner to take on the responsibility.
- */
- if (atomic_read(&mm->mm_users) <= 1)
- return 0;
- if (mm->owner != p)
- return 0;
- return 1;
-}
-
void mm_update_next_owner(struct mm_struct *mm)
{
struct task_struct *c, *g, *p = current;
retry:
- if (!mm_need_new_owner(mm, p))
+ /*
+ * If the exiting or execing task is not the owner, it's
+ * someone else's problem.
+ */
+ if (mm->owner != p)
return;
+ /*
+ * The current owner is exiting/execing and there are no other
+ * candidates. Do not leave the mm pointing to a possibly
+ * freed task structure.
+ */
+ if (atomic_read(&mm->mm_users) <= 1) {
+ mm->owner = NULL;
+ return;
+ }
read_lock(&tasklist_lock);
/*
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