Code that does lockless emptiness testing of non-RCU lists is relying on INIT_LIST_HEAD() to write the list head's ->next pointer atomically, particularly when INIT_LIST_HEAD() is invoked from list_del_init(). This commit therefore adds WRITE_ONCE() to this function's pointer stores that could affect the head's ->next pointer.
Reported-by: Andrey Konovalov <[email protected]> Signed-off-by: Paul E. McKenney <[email protected]> --- include/linux/list.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/list.h b/include/linux/list.h index 06c2d887a918..5356f4d661a7 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -24,7 +24,7 @@ static inline void INIT_LIST_HEAD(struct list_head *list) { - list->next = list; + WRITE_ONCE(list->next, list); list->prev = list; } -- 2.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
