diff --git a/[refs] b/[refs]
index 06f8ef7faeab..e0d5d5157f6a 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 975b365895b638a62da55f9fb180b0a71d05874d
+refs/heads/master: f86c9747fe1cd72b2c5c6bdf72d17aeb2a3c6cb0
diff --git a/trunk/arch/powerpc/mm/mmu_context_64.c b/trunk/arch/powerpc/mm/mmu_context_64.c
index 65d18dca266f..e2051efa09c5 100644
--- a/trunk/arch/powerpc/mm/mmu_context_64.c
+++ b/trunk/arch/powerpc/mm/mmu_context_64.c
@@ -44,7 +44,9 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
 		return err;
 
 	if (index > MAX_CONTEXT) {
+		spin_lock(&mmu_context_lock);
 		idr_remove(&mmu_context_idr, index);
+		spin_unlock(&mmu_context_lock);
 		return -ENOMEM;
 	}