1 files changed, 24 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index b8e6189298f4..174e1e96175e 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -83,11 +83,29 @@ static int __init early_parse_mem(char *p)
 }
 early_param("mem", early_parse_mem);
 
+/*
+ * overlaps_initrd - check for overlap with page aligned extension of
+ * initrd.
+ */
+static inline int overlaps_initrd(unsigned long start, unsigned long size)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+        if (!initrd_start)
+                return 0;
+
+        return  (start + size) > _ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
+                        start <= _ALIGN_UP(initrd_end, PAGE_SIZE);
+#else
+        return 0;
+#endif
+}
+
 /**
  * move_device_tree - move tree to an unused area, if needed.
  *
  * The device tree may be allocated beyond our memory limit, or inside the
- * crash kernel region for kdump. If so, move it out of the way.
+ * crash kernel region for kdump, or within the page aligned range of initrd.
+ * If so, move it out of the way.
  */
 static void __init move_device_tree(void)
 {
@@ -100,7 +118,8 @@ static void __init move_device_tree(void)
         size = be32_to_cpu(initial_boot_params->totalsize);
 
         if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
-                        overlaps_crashkernel(start, size)) {
+                        overlaps_crashkernel(start, size) ||
+                        overlaps_initrd(start, size)) {
                 p = __va(memblock_alloc(size, PAGE_SIZE));
                 memcpy(p, initial_boot_params, size);
                 initial_boot_params = (struct boot_param_header *)p;
@@ -556,7 +575,9 @@ static void __init early_reserve_mem(void)
 #ifdef CONFIG_BLK_DEV_INITRD
         /* then reserve the initrd, if any */
         if (initrd_start && (initrd_end > initrd_start))
-                memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
+                memblock_reserve(_ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
+                        _ALIGN_UP(initrd_end, PAGE_SIZE) -
+                        _ALIGN_DOWN(initrd_start, PAGE_SIZE));
 #endif /* CONFIG_BLK_DEV_INITRD */
 
 #ifdef CONFIG_PPC32