--- arch/x86/mm/init_64.c

+++ arch/x86/mm/init_64.c

@@ -49,6 +49,8 @@

#include <asm/numa.h>

#include <asm/cacheflush.h>

#include <asm/init.h>

+#include <asm/setup.h>

+#include <linux/bootmem.h>

static unsigned long dma_reserve __initdata;

@@ -256,18 +258,18 @@ void __init init_extra_mapping_uc(unsign

* to the compile time generated pmds. This results in invalid pmds up

* to the point where we hit the physaddr 0 mapping.

*

- * We limit the mappings to the region from _text to _end. _end is

- * rounded up to the 2MB boundary. This catches the invalid pmds as

+ * We limit the mappings to the region from _text to _brk_end. _brk_end

+ * is rounded up to the 2MB boundary. This catches the invalid pmds as

* well, as they are located before _text:

*/

void __init cleanup_highmap(void)

{

unsigned long vaddr = __START_KERNEL_map;

- unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;

+ unsigned long vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);

+ unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;

pmd_t *pmd = level2_kernel_pgt;

- pmd_t *last_pmd = pmd + PTRS_PER_PMD;

- for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {

+ for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {

if (pmd_none(*pmd))

continue;

if (vaddr < (unsigned long) _text || vaddr > end)

@@ -615,6 +617,21 @@ void __init paging_init(void)

*/

#ifdef CONFIG_MEMORY_HOTPLUG

/*

+ * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need

+ * updating.

+ */

+static void update_end_of_memory_vars(u64 start, u64 size)

+{

+ unsigned long end_pfn = PFN_UP(start + size);

+

+ if (end_pfn > max_pfn) {

+ max_pfn = end_pfn;

+ max_low_pfn = end_pfn;

+ high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;

+ }

+}

+

+/*

* Memory is added always to NORMAL zone. This means you will never get

* additional DMA/DMA32 memory.

*/

@@ -633,6 +650,9 @@ int arch_add_memory(int nid, u64 start,

ret = __add_pages(nid, zone, start_pfn, nr_pages);

WARN_ON_ONCE(ret);

+ /* update max_pfn, max_low_pfn and high_memory */

+ update_end_of_memory_vars(start, size);

+

return ret;

}

EXPORT_SYMBOL_GPL(arch_add_memory);