Merge branch 'akpm' (more incoming from Andrew)

Merge second patch-bomb from Andrew Morton:

 - A little DM fix

 - the MM queue

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (154 commits)
  ksm: allocate roots when needed
  mm: cleanup "swapcache" in do_swap_page
  mm,ksm: swapoff might need to copy
  mm,ksm: FOLL_MIGRATION do migration_entry_wait
  ksm: shrink 32-bit rmap_item back to 32 bytes
  ksm: treat unstable nid like in stable tree
  ksm: add some comments
  tmpfs: fix mempolicy object leaks
  tmpfs: fix use-after-free of mempolicy object
  mm/fadvise.c: drain all pagevecs if POSIX_FADV_DONTNEED fails to discard all pages
  mm: export mmu notifier invalidates
  mm: accelerate mm_populate() treatment of THP pages
  mm: use long type for page counts in mm_populate() and get_user_pages()
  mm: accurately document nr_free_*_pages functions with code comments
  HWPOISON: change order of error_states[]'s elements
  HWPOISON: fix misjudgement of page_action() for errors on mlocked pages
  memcg: stop warning on memcg_propagate_kmem
  net: change type of virtio_chan->p9_max_pages
  vmscan: change type of vm_total_pages to unsigned long
  fs/nfsd: change type of max_delegations, nfsd_drc_max_mem and nfsd_drc_mem_used
  ...

1 files changed, 19 insertions, 9 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 3a673a3b0c6b..053dfd7692d1 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1132,18 +1132,28 @@ EXPORT_SYMBOL_GPL(kick_process);
  */
 static int select_fallback_rq(int cpu, struct task_struct *p)
 {
-        const struct cpumask *nodemask = cpumask_of_node(cpu_to_node(cpu));
+        int nid = cpu_to_node(cpu);
+        const struct cpumask *nodemask = NULL;
         enum { cpuset, possible, fail } state = cpuset;
         int dest_cpu;
 
-        /* Look for allowed, online CPU in same node. */
-        for_each_cpu(dest_cpu, nodemask) {
-                if (!cpu_online(dest_cpu))
-                        continue;
-                if (!cpu_active(dest_cpu))
-                        continue;
-                if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
-                        return dest_cpu;
+        /*
+         * If the node that the cpu is on has been offlined, cpu_to_node()
+         * will return -1. There is no cpu on the node, and we should
+         * select the cpu on the other node.
+         */
+        if (nid != -1) {
+                nodemask = cpumask_of_node(nid);
+
+                /* Look for allowed, online CPU in same node. */
+                for_each_cpu(dest_cpu, nodemask) {
+                        if (!cpu_online(dest_cpu))
+                                continue;
+                        if (!cpu_active(dest_cpu))
+                                continue;
+                        if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+                                return dest_cpu;
+                }
         }
 
         for (;;) {