---

yaml
---
r: 310639
b: refs/heads/master
c: c3decf0
h: refs/heads/master
i:
  310637: 532d71f
  310635: a3836f8
  310631: 0677786
  310623: 29e8975
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c1174876874dcf8986806e4dad3d7d07af20b439
+refs/heads/master: c3decf0dfbc95736b7c0ab68fa4e5854c4734da9

trunk/kernel/sched/core.c

@@ -5604,7 +5604,12 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
 			break;
 		}
 
-		if (!group->sgp->power) {
+		/*
+		 * Even though we initialize ->power to something semi-sane,
+		 * we leave power_orig unset. This allows us to detect if
+		 * domain iteration is still funny without causing /0 traps.
+		 */
+		if (!group->sgp->power_orig) {
 			printk(KERN_CONT "\n");
 			printk(KERN_ERR "ERROR: domain->cpu_power not "
 					"set\n");
@@ -6075,6 +6080,12 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
 		if (atomic_inc_return(&sg->sgp->ref) == 1)
 			build_group_mask(sd, sg);
 
+		/*
+		 * Initialize sgp->power such that even if we mess up the
+		 * domains and no possible iteration will get us here, we won't
+		 * die on a /0 trap.
+		 */
+		sg->sgp->power = SCHED_POWER_SCALE * cpumask_weight(sg_span);
 
 		/*
 		 * Make sure the first group of this domain contains the

trunk/kernel/sched/fair.c

@@ -3602,7 +3602,7 @@ void update_group_power(struct sched_domain *sd, int cpu)
 		} while (group != child->groups);
 	}
 
-	sdg->sgp->power = power;
+	sdg->sgp->power_orig = sdg->sgp->power = power;
 }
 
 /*