1 files changed, 18 insertions, 6 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1521100f1e63..3222193c46c6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6383,7 +6383,7 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
         free_area_init_core(pgdat);
 }
 
-#ifdef CONFIG_HAVE_MEMBLOCK
+#if defined(CONFIG_HAVE_MEMBLOCK) && !defined(CONFIG_FLAT_NODE_MEM_MAP)
 /*
  * Only struct pages that are backed by physical memory are zeroed and
  * initialized by going through __init_single_page(). But, there are some
@@ -6421,7 +6421,7 @@ void __paginginit zero_resv_unavail(void)
         if (pgcnt)
                 pr_info("Reserved but unavailable: %lld pages", pgcnt);
 }
-#endif /* CONFIG_HAVE_MEMBLOCK */
+#endif /* CONFIG_HAVE_MEMBLOCK && !CONFIG_FLAT_NODE_MEM_MAP */
 
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 
@@ -6847,6 +6847,7 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
         /* Initialise every node */
         mminit_verify_pageflags_layout();
         setup_nr_node_ids();
+        zero_resv_unavail();
         for_each_online_node(nid) {
                 pg_data_t *pgdat = NODE_DATA(nid);
                 free_area_init_node(nid, NULL,
@@ -6857,7 +6858,6 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
                         node_set_state(nid, N_MEMORY);
                 check_for_memory(pgdat, nid);
         }
-        zero_resv_unavail();
 }
 
 static int __init cmdline_parse_core(char *p, unsigned long *core,
@@ -6939,9 +6939,21 @@ unsigned long free_reserved_area(void *start, void *end, int poison, char *s)
         start = (void *)PAGE_ALIGN((unsigned long)start);
         end = (void *)((unsigned long)end & PAGE_MASK);
         for (pos = start; pos < end; pos += PAGE_SIZE, pages++) {
+                struct page *page = virt_to_page(pos);
+                void *direct_map_addr;
+
+                /*
+                 * 'direct_map_addr' might be different from 'pos'
+                 * because some architectures' virt_to_page()
+                 * work with aliases.  Getting the direct map
+                 * address ensures that we get a _writeable_
+                 * alias for the memset().
+                 */
+                direct_map_addr = page_address(page);
                 if ((unsigned int)poison <= 0xFF)
-                        memset(pos, poison, PAGE_SIZE);
-                free_reserved_page(virt_to_page(pos));
+                        memset(direct_map_addr, poison, PAGE_SIZE);
+
+                free_reserved_page(page);
         }
 
         if (pages && s)
@@ -7033,9 +7045,9 @@ void __init set_dma_reserve(unsigned long new_dma_reserve)
 
 void __init free_area_init(unsigned long *zones_size)
 {
+        zero_resv_unavail();
         free_area_init_node(0, zones_size,
                         __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
-        zero_resv_unavail();
 }
 
 static int page_alloc_cpu_dead(unsigned int cpu)