1 files changed, 25 insertions, 8 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3e00526f52ec..96c0ba13b8cd 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -36,6 +36,7 @@
 #include <linux/list.h>
 #include <linux/mempolicy.h>
 #include <linux/mm.h>
+#include <linux/memory.h>
 #include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
@@ -584,10 +585,9 @@ static int generate_sched_domains(cpumask_t **domains,
         int i, j, k;            /* indices for partition finding loops */
         cpumask_t *doms;        /* resulting partition; i.e. sched domains */
         struct sched_domain_attr *dattr;  /* attributes for custom domains */
-        int ndoms;              /* number of sched domains in result */
+        int ndoms = 0;          /* number of sched domains in result */
         int nslot;              /* next empty doms[] cpumask_t slot */
 
-        ndoms = 0;
         doms = NULL;
         dattr = NULL;
         csa = NULL;
@@ -674,10 +674,8 @@ restart:
          * 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 +730,13 @@ restart:
 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;
@@ -2011,12 +2016,23 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb,
  * Call this routine anytime after node_states[N_HIGH_MEMORY] changes.
  * See also the previous routine cpuset_track_online_cpus().
  */
-void cpuset_track_online_nodes(void)
+static int cpuset_track_online_nodes(struct notifier_block *self,
+                                unsigned long action, void *arg)
 {
         cgroup_lock();
-        top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
-        scan_for_empty_cpusets(&top_cpuset);
+        switch (action) {
+        case MEM_ONLINE:
+                top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+                break;
+        case MEM_OFFLINE:
+                top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+                scan_for_empty_cpusets(&top_cpuset);
+                break;
+        default:
+                break;
+        }
         cgroup_unlock();
+        return NOTIFY_OK;
 }
 #endif
 
@@ -2032,6 +2048,7 @@ void __init cpuset_init_smp(void)
         top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
 
         hotcpu_notifier(cpuset_track_online_cpus, 0);
+        hotplug_memory_notifier(cpuset_track_online_nodes, 10);
 }
 
 /**