--- arch/x86/xen/mmu.c

+++ arch/x86/xen/mmu.c

@@ -1658,9 +1658,6 @@ static __init void xen_map_identity_earl

for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {

pte_t pte;

- if (pfn > max_pfn_mapped)

- max_pfn_mapped = pfn;

-

if (!pte_none(pte_page[pteidx]))

continue;

@@ -1704,6 +1701,12 @@ __init pgd_t *xen_setup_kernel_pagetable

pud_t *l3;

pmd_t *l2;

+ /* max_pfn_mapped is the last pfn mapped in the initial memory

+ * mappings. Considering that on Xen after the kernel mappings we

+ * have the mappings of some pages that don't exist in pfn space, we

+ * set max_pfn_mapped to the last real pfn mapped. */

+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));

+

/* Zap identity mapping */

init_level4_pgt[0] = __pgd(0);

@@ -1767,9 +1770,7 @@ __init pgd_t *xen_setup_kernel_pagetable

{

pmd_t *kernel_pmd;

- max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) +

- xen_start_info->nr_pt_frames * PAGE_SIZE +

- 512*1024);

+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));

kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);

memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);