xen: update mask_rw_pte after kernel page tables init changes

[pandora-kernel.git] / arch / x86 / xen / mmu.c

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 832765c..21058ad 100644 (file)
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1488,10 +1488,12 @@ static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
        /*
         * If the new pfn is within the range of the newly allocated
         * kernel pagetable, and it isn't being mapped into an
-        * early_ioremap fixmap slot, make sure it is RO.
+        * early_ioremap fixmap slot as a freshly allocated page, make sure
+        * it is RO.
         */
-       if (!is_early_ioremap_ptep(ptep) &&
-           pfn >= e820_table_start && pfn < e820_table_end)
+       if (((!is_early_ioremap_ptep(ptep) &&
+                       pfn >= pgt_buf_start && pfn < pgt_buf_end)) ||
+                       (is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1)))
                pte = pte_wrprotect(pte);
 
        return pte;
@@ -1701,9 +1703,6 @@ static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
                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;
 
@@ -1745,7 +1744,7 @@ static void convert_pfn_mfn(void *v)
 }
 
 /*
- * Set up the inital kernel pagetable.
+ * Set up the initial kernel pagetable.
  *
  * We can construct this by grafting the Xen provided pagetable into
  * head_64.S's preconstructed pagetables.  We copy the Xen L2's into
@@ -1761,6 +1760,12 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
        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);
 
@@ -1865,9 +1870,7 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
        initial_kernel_pmd =
                extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);
 
-       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(initial_kernel_pmd, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);