From 4a0fbd63c8261b8655b9c0189b55d33da7788a40 Mon Sep 17 00:00:00 2001
From: Li Zefan <lizf@cn.fujitsu.com>
Date: Tue, 18 Nov 2008 14:02:03 +0800
Subject: [PATCH] --- yaml --- r: 119151 b: refs/heads/master c:
 700018e0a77b4113172257fcdaa1c58e27a5074f h: refs/heads/master i:   119149:
 4a4efcdaee2927a743b134c7614affdcc58e789c   119147:
 d3e6bee704fdb8f6741edb5475843b5cfcedd69c   119143:
 120d1859e04a93500b047c82068ee5af582fbeea   119135:
 8fc27e0bda4fda15abc377e2bea04ab4fc0a8aff v: v3

---
 [refs]                |  2 +-
 trunk/kernel/cpuset.c | 12 ++++++++----
 trunk/kernel/sched.c  | 13 +++++++------
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/[refs] b/[refs]
index d2338f56531e..7088ddcb0c27 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ad133ba3dc283300e5b62b5b7211d2f39fbf6ee7
+refs/heads/master: 700018e0a77b4113172257fcdaa1c58e27a5074f
diff --git a/trunk/kernel/cpuset.c b/trunk/kernel/cpuset.c
index 3e00526f52ec..81fc6791a296 100644
--- a/trunk/kernel/cpuset.c
+++ b/trunk/kernel/cpuset.c
@@ -587,7 +587,6 @@ static int generate_sched_domains(cpumask_t **domains,
 	int ndoms;		/* number of sched domains in result */
 	int nslot;		/* next empty doms[] cpumask_t slot */
 
-	ndoms = 0;
 	doms = NULL;
 	dattr = NULL;
 	csa = NULL;
@@ -674,10 +673,8 @@ static int generate_sched_domains(cpumask_t **domains,
 	 * Convert <csn, csa> to <ndoms, doms> and populate cpu masks.
 	 */
 	doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL);
-	if (!doms) {
-		ndoms = 0;
+	if (!doms)
 		goto done;
-	}
 
 	/*
 	 * The rest of the code, including the scheduler, can deal with
@@ -732,6 +729,13 @@ static int generate_sched_domains(cpumask_t **domains,
 done:
 	kfree(csa);
 
+	/*
+	 * Fallback to the default domain if kmalloc() failed.
+	 * See comments in partition_sched_domains().
+	 */
+	if (doms == NULL)
+		ndoms = 1;
+
 	*domains    = doms;
 	*attributes = dattr;
 	return ndoms;
diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
index c94baf2969e7..9b1e79371c20 100644
--- a/trunk/kernel/sched.c
+++ b/trunk/kernel/sched.c
@@ -7789,13 +7789,14 @@ static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
  *
  * The passed in 'doms_new' should be kmalloc'd. This routine takes
  * ownership of it and will kfree it when done with it. If the caller
- * failed the kmalloc call, then it can pass in doms_new == NULL,
- * and partition_sched_domains() will fallback to the single partition
- * 'fallback_doms', it also forces the domains to be rebuilt.
+ * failed the kmalloc call, then it can pass in doms_new == NULL &&
+ * ndoms_new == 1, and partition_sched_domains() will fallback to
+ * the single partition 'fallback_doms', it also forces the domains
+ * to be rebuilt.
  *
- * If doms_new==NULL it will be replaced with cpu_online_map.
- * ndoms_new==0 is a special case for destroying existing domains.
- * It will not create the default domain.
+ * If doms_new == NULL it will be replaced with cpu_online_map.
+ * ndoms_new == 0 is a special case for destroying existing domains,
+ * and it will not create the default domain.
  *
  * Call with hotplug lock held
  */