From 1146edcbef3789228454c4aa42c08ddc2c275990 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 9 Jun 2014 08:24:17 -0700 Subject: [PATCH] rcu: Loosen __call_rcu()'s rcu_head alignment constraint The m68k architecture aligns only to 16-bit boundaries, which can cause the align-to-32-bits check in __call_rcu() to trigger. Because there is currently no known potential need for more than one low-order bit, this commit loosens the check to 16-bit boundaries. Reported-by: Greg Ungerer Signed-off-by: Paul E. McKenney Reviewed-by: Lai Jiangshan --- kernel/rcu/tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 6bf7daebcc6b..bcd635e42841 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2662,7 +2662,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), unsigned long flags; struct rcu_data *rdp; - WARN_ON_ONCE((unsigned long)head & 0x3); /* Misaligned rcu_head! */ + WARN_ON_ONCE((unsigned long)head & 0x1); /* Misaligned rcu_head! */ if (debug_rcu_head_queue(head)) { /* Probable double call_rcu(), so leak the callback. */ ACCESS_ONCE(head->func) = rcu_leak_callback;