1 files changed, 27 insertions, 2 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 3231bf332878..e583f770dfee 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1118,6 +1118,32 @@ void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t pro
 EXPORT_SYMBOL(vm_map_ram);
 
 /**
+ * vm_area_add_early - add vmap area early during boot
+ * @vm: vm_struct to add
+ *
+ * This function is used to add fixed kernel vm area to vmlist before
+ * vmalloc_init() is called.  @vm->addr, @vm->size, and @vm->flags
+ * should contain proper values and the other fields should be zero.
+ *
+ * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
+ */
+void __init vm_area_add_early(struct vm_struct *vm)
+{
+        struct vm_struct *tmp, **p;
+
+        BUG_ON(vmap_initialized);
+        for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
+                if (tmp->addr >= vm->addr) {
+                        BUG_ON(tmp->addr < vm->addr + vm->size);
+                        break;
+                } else
+                        BUG_ON(tmp->addr + tmp->size > vm->addr);
+        }
+        vm->next = *p;
+        *p = vm;
+}
+
+/**
  * vm_area_register_early - register vmap area early during boot
  * @vm: vm_struct to register
  * @align: requested alignment
@@ -1139,8 +1165,7 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align)
 
         vm->addr = (void *)addr;
 
-        vm->next = vmlist;
-        vmlist = vm;
+        vm_area_add_early(vm);
 }
 
 void __init vmalloc_init(void)