x86: fix init_memory_mapping over boundary v3

some ram-end boundary only has page alignment, instead of 2M alignment.

v2: make init_memory_mapping more solid: start could be any value other than 0
v3: fix NON PAE by handling left over in kernel_physical_mapping

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index b9cf7f70530207c844917c403f098a37073f9079..90ca67be965b03416db7ada47b665cd3f5619d6e 100644 (file)
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -195,7 +195,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
        unsigned pages_2m = 0, pages_4k = 0;
        unsigned limit_pfn = end >> PAGE_SHIFT;
 
-       pgd_idx = pgd_index(PAGE_OFFSET);
+       pgd_idx = pgd_index(start + PAGE_OFFSET);
        pgd = pgd_base + pgd_idx;
        pfn = start >> PAGE_SHIFT;
 
@@ -218,7 +218,8 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
                         * and overlapping MTRRs into large pages can cause
                         * slowdowns.
                         */
-                       if (cpu_has_pse && !(pgd_idx == 0 && pmd_idx == 0)) {
+                       if (cpu_has_pse && !(pgd_idx == 0 && pmd_idx == 0) &&
+                               (pfn + PTRS_PER_PTE) <= limit_pfn) {
                                unsigned int addr2;
                                pgprot_t prot = PAGE_KERNEL_LARGE;
 
@@ -233,13 +234,12 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
                                set_pmd(pmd, pfn_pmd(pfn, prot));
 
                                pfn += PTRS_PER_PTE;
-                               max_pfn_mapped = pfn;
                                continue;
                        }
                        pte = one_page_table_init(pmd);
 
                        for (pte_ofs = 0;
-                            pte_ofs < PTRS_PER_PTE && pfn < max_low_pfn;
+                            pte_ofs < PTRS_PER_PTE && pfn < limit_pfn;
                             pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) {
                                pgprot_t prot = PAGE_KERNEL;
 
@@ -249,7 +249,6 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
                                pages_4k++;
                                set_pte(pte, pfn_pte(pfn, prot));
                        }
-                       max_pfn_mapped = pfn;
                }
        }
        update_page_count(PG_LEVEL_2M, pages_2m);
@@ -729,7 +728,7 @@ void __init setup_bootmem_allocator(void)
 
 static void __init find_early_table_space(unsigned long end)
 {
-       unsigned long puds, pmds, tables, start;
+       unsigned long puds, pmds, ptes, tables, start;
 
        puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
        tables = PAGE_ALIGN(puds * sizeof(pud_t));
@@ -737,10 +736,15 @@ static void __init find_early_table_space(unsigned long end)
        pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
        tables += PAGE_ALIGN(pmds * sizeof(pmd_t));
 
-       if (!cpu_has_pse) {
-               int ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
-               tables += PAGE_ALIGN(ptes * sizeof(pte_t));
-       }
+       if (cpu_has_pse) {
+               unsigned long extra;
+               extra = end - ((end>>21) << 21);
+               extra += (2UL<<20);
+               ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
+       } else
+               ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+       tables += PAGE_ALIGN(ptes * sizeof(pte_t));
 
        /*
         * RED-PEN putting page tables only on node 0 could