diff --git a/mm/memblock.c b/mm/memblock.c
index 5d2a991..7949841 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -19,6 +19,8 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/memblock.h>
+#include <linux/preempt.h>
+#include <linux/seqlock.h>
 
 #include <asm/sections.h>
 #include <linux/io.h>
@@ -31,6 +33,7 @@
 static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS] __initdata_memblock;
 #endif
 
+static seqcount_t memblock_seq;
 struct memblock memblock __initdata_memblock = {
 	.memory.regions		= memblock_memory_init_regions,
 	.memory.cnt		= 1,	/* empty dummy entry */
@@ -1541,7 +1544,8 @@
 			      (phys_addr_t)ULLONG_MAX);
 }
 
-static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
+static int __init_memblock __memblock_search(struct memblock_type *type,
+					     phys_addr_t addr)
 {
 	unsigned int left = 0, right = type->cnt;
 
@@ -1559,6 +1563,20 @@
 	return -1;
 }
 
+static int __init_memblock memblock_search(struct memblock_type *type,
+					   phys_addr_t addr)
+{
+	int ret;
+	unsigned long seq;
+
+	do {
+		seq = raw_read_seqcount_begin(&memblock_seq);
+		ret = __memblock_search(type, addr);
+	} while (unlikely(read_seqcount_retry(&memblock_seq, seq)));
+
+	return ret;
+}
+
 bool __init memblock_is_reserved(phys_addr_t addr)
 {
 	return memblock_search(&memblock.reserved, addr) != -1;
@@ -1716,6 +1734,32 @@
 	memblock_can_resize = 1;
 }
 
+static void __init_memblock memblock_resize_late(int begin)
+{
+	static int memblock_can_resize_old;
+
+	if (begin) {
+		preempt_disable();
+		memblock_can_resize_old = memblock_can_resize;
+		memblock_can_resize = 0;
+		raw_write_seqcount_begin(&memblock_seq);
+	} else {
+		raw_write_seqcount_end(&memblock_seq);
+		memblock_can_resize = memblock_can_resize_old;
+		preempt_enable();
+	}
+}
+
+void __init_memblock memblock_region_resize_late_begin(void)
+{
+	memblock_resize_late(1);
+}
+
+void __init_memblock memblock_region_resize_late_end(void)
+{
+	memblock_resize_late(0);
+}
+
 static int __init early_memblock(char *p)
 {
 	if (p && strstr(p, "debug"))