1 files changed, 37 insertions, 16 deletions

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 508bec1cee27..95b81c18b6bc 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -110,19 +110,25 @@ int __init e820_all_mapped(u64 start, u64 end, unsigned type)
 /*
  * Add a memory region to the kernel e820 map.
  */
-void __init e820_add_region(u64 start, u64 size, int type)
+static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
+                                         int type)
 {
-        int x = e820.nr_map;
+        int x = e820x->nr_map;
 
-        if (x == ARRAY_SIZE(e820.map)) {
+        if (x == ARRAY_SIZE(e820x->map)) {
                 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
                 return;
         }
 
-        e820.map[x].addr = start;
-        e820.map[x].size = size;
-        e820.map[x].type = type;
-        e820.nr_map++;
+        e820x->map[x].addr = start;
+        e820x->map[x].size = size;
+        e820x->map[x].type = type;
+        e820x->nr_map++;
+}
+
+void __init e820_add_region(u64 start, u64 size, int type)
+{
+        __e820_add_region(&e820, start, size, type);
 }
 
 void __init e820_print_map(char *who)
@@ -417,11 +423,11 @@ static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
         return __append_e820_map(biosmap, nr_map);
 }
 
-static u64 __init e820_update_range_map(struct e820map *e820x, u64 start,
+static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
                                         u64 size, unsigned old_type,
                                         unsigned new_type)
 {
-        int i;
+        unsigned int i;
         u64 real_updated_size = 0;
 
         BUG_ON(old_type == new_type);
@@ -429,7 +435,7 @@ static u64 __init e820_update_range_map(struct e820map *e820x, u64 start,
         if (size > (ULLONG_MAX - start))
                 size = ULLONG_MAX - start;
 
-        for (i = 0; i < e820.nr_map; i++) {
+        for (i = 0; i < e820x->nr_map; i++) {
                 struct e820entry *ei = &e820x->map[i];
                 u64 final_start, final_end;
                 if (ei->type != old_type)
@@ -446,10 +452,16 @@ static u64 __init e820_update_range_map(struct e820map *e820x, u64 start,
                 final_end = min(start + size, ei->addr + ei->size);
                 if (final_start >= final_end)
                         continue;
-                e820_add_region(final_start, final_end - final_start,
-                                         new_type);
+
+                __e820_add_region(e820x, final_start, final_end - final_start,
+                                  new_type);
+
                 real_updated_size += final_end - final_start;
 
+                /*
+                 * left range could be head or tail, so need to update
+                 * size at first.
+                 */
                 ei->size -= final_end - final_start;
                 if (ei->addr < final_start)
                         continue;
@@ -461,13 +473,13 @@ static u64 __init e820_update_range_map(struct e820map *e820x, u64 start,
 u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
                              unsigned new_type)
 {
-        return e820_update_range_map(&e820, start, size, old_type, new_type);
+        return __e820_update_range(&e820, start, size, old_type, new_type);
 }
 
 static u64 __init e820_update_range_saved(u64 start, u64 size,
                                           unsigned old_type, unsigned new_type)
 {
-        return e820_update_range_map(&e820_saved, start, size, old_type,
+        return __e820_update_range(&e820_saved, start, size, old_type,
                                      new_type);
 }
 
@@ -1020,8 +1032,8 @@ u64 __init find_e820_area_size(u64 start, u64 *sizep, u64 align)
                         continue;
                 return addr;
         }
-        return -1UL;
 
+        return -1ULL;
 }
 
 /*
@@ -1034,13 +1046,22 @@ u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
         u64 start;
 
         start = startt;
-        while (size < sizet)
+        while (size < sizet && (start + 1))
                 start = find_e820_area_size(start, &size, align);
 
         if (size < sizet)
                 return 0;
 
+#ifdef CONFIG_X86_32
+        if (start >= MAXMEM)
+                return 0;
+        if (start + size > MAXMEM)
+                size = MAXMEM - start;
+#endif
+
         addr = round_down(start + size - sizet, align);
+        if (addr < start)
+                return 0;
         e820_update_range(addr, sizet, E820_RAM, E820_RESERVED);
         e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
         printk(KERN_INFO "update e820 for early_reserve_e820\n");