1 files changed, 18 insertions, 5 deletions

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 15739a95552a..d1e26610977d 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -231,6 +231,9 @@ phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
 static void __init arm_initrd_init(void)
 {
 #ifdef CONFIG_BLK_DEV_INITRD
+        phys_addr_t start;
+        unsigned long size;
+
         /* FDT scan will populate initrd_start */
         if (initrd_start && !phys_initrd_size) {
                 phys_initrd_start = __virt_to_phys(initrd_start);
@@ -242,19 +245,29 @@ static void __init arm_initrd_init(void)
         if (!phys_initrd_size)
                 return;
 
-        if (!memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
+        /*
+         * Round the memory region to page boundaries as per free_initrd_mem()
+         * This allows us to detect whether the pages overlapping the initrd
+         * are in use, but more importantly, reserves the entire set of pages
+         * as we don't want these pages allocated for other purposes.
+         */
+        start = round_down(phys_initrd_start, PAGE_SIZE);
+        size = phys_initrd_size + (phys_initrd_start - start);
+        size = round_up(size, PAGE_SIZE);
+
+        if (!memblock_is_region_memory(start, size)) {
                 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
-                       (u64)phys_initrd_start, phys_initrd_size);
+                       (u64)start, size);
                 return;
         }
 
-        if (memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
+        if (memblock_is_region_reserved(start, size)) {
                 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
-                       (u64)phys_initrd_start, phys_initrd_size);
+                       (u64)start, size);
                 return;
         }
 
-        memblock_reserve(phys_initrd_start, phys_initrd_size);
+        memblock_reserve(start, size);
 
         /* Now convert initrd to virtual addresses */
         initrd_start = __phys_to_virt(phys_initrd_start);