x86: overmapped fix when 4K pages on tail, 64-bit

fix phys_pmd_init to make sure not to return bigger value than end.

also print out range split:1G/2M/4K in init_memory_mapping().

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 51f69b3..48548ef 100644 (file)
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -302,11 +302,13 @@ static __meminit void unmap_low_page(void *adr)
        early_iounmap(adr, PAGE_SIZE);
 }
 
-static void __meminit
+static unsigned long __meminit
 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end)
 {
        unsigned pages = 0;
+       unsigned long last_map_addr = end;
        int i;
+
        pte_t *pte = pte_page + pte_index(addr);
 
        for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
@@ -326,17 +328,20 @@ phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end)
                        printk("   pte=%p addr=%lx pte=%016lx\n",
                               pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
                set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL));
+               last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
                pages++;
        }
        update_page_count(PG_LEVEL_4K, pages);
+
+       return last_map_addr;
 }
 
-static void __meminit
+static unsigned long __meminit
 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end)
 {
        pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
 
-       phys_pte_init(pte, address, end);
+       return phys_pte_init(pte, address, end);
 }
 
 static unsigned long __meminit
@@ -344,6 +349,7 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
                         unsigned long page_size_mask)
 {
        unsigned long pages = 0;
+       unsigned long last_map_addr = end;
 
        int i = pmd_index(address);
 
@@ -362,7 +368,8 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
 
                if (pmd_val(*pmd)) {
                        if (!pmd_large(*pmd))
-                               phys_pte_update(pmd, address, end);
+                               last_map_addr = phys_pte_update(pmd, address,
+                                                                end);
                        continue;
                }
 
@@ -370,17 +377,18 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
                        pages++;
                        set_pte((pte_t *)pmd,
                                pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
+                       last_map_addr = (address & PMD_MASK) + PMD_SIZE;
                        continue;
                }
 
                pte = alloc_low_page(&pte_phys);
-               phys_pte_init(pte, address, end);
+               last_map_addr = phys_pte_init(pte, address, end);
                unmap_low_page(pte);
 
                pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
        }
        update_page_count(PG_LEVEL_2M, pages);
-       return address;
+       return last_map_addr;
 }
 
 static unsigned long __meminit
@@ -659,6 +667,32 @@ static unsigned long __init kernel_physical_mapping_init(unsigned long start,
 
        return last_map_addr;
 }
+
+struct map_range {
+       unsigned long start;
+       unsigned long end;
+       unsigned page_size_mask;
+};
+
+#define NR_RANGE_MR 5
+
+static int save_mr(struct map_range *mr, int nr_range,
+                  unsigned long start_pfn, unsigned long end_pfn,
+                  unsigned long page_size_mask)
+{
+
+       if (start_pfn < end_pfn) {
+               if (nr_range >= NR_RANGE_MR)
+                       panic("run out of range for init_memory_mapping\n");
+               mr[nr_range].start = start_pfn<<PAGE_SHIFT;
+               mr[nr_range].end   = end_pfn<<PAGE_SHIFT;
+               mr[nr_range].page_size_mask = page_size_mask;
+               nr_range++;
+       }
+
+       return nr_range;
+}
+
 /*
  * Setup the direct mapping of the physical memory at PAGE_OFFSET.
  * This runs before bootmem is initialized and gets pages directly from
@@ -667,10 +701,13 @@ static unsigned long __init kernel_physical_mapping_init(unsigned long start,
 unsigned long __init_refok init_memory_mapping(unsigned long start,
                                               unsigned long end)
 {
-       unsigned long last_map_addr = end;
+       unsigned long last_map_addr = 0;
        unsigned long page_size_mask = 0;
        unsigned long start_pfn, end_pfn;
 
+       struct map_range mr[NR_RANGE_MR];
+       int nr_range, i;
+
        printk(KERN_INFO "init_memory_mapping\n");
 
        /*
@@ -680,24 +717,22 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
         * memory mapped. Unfortunately this is done currently before the
         * nodes are discovered.
         */
-       if (!after_bootmem) {
+       if (!after_bootmem)
                init_gbpages();
-               find_early_table_space(end);
-       }
 
        if (direct_gbpages)
                page_size_mask |= 1 << PG_LEVEL_1G;
        if (cpu_has_pse)
                page_size_mask |= 1 << PG_LEVEL_2M;
 
-       /* head if not big page aligment ?*/
+       memset(mr, 0, sizeof(mr));
+       nr_range = 0;
+
+       /* head if not big page alignment ?*/
        start_pfn = start >> PAGE_SHIFT;
        end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
                        << (PMD_SHIFT - PAGE_SHIFT);
-       if (start_pfn < end_pfn)
-               last_map_addr = kernel_physical_mapping_init(
-                                       start_pfn<<PAGE_SHIFT,
-                                       end_pfn<<PAGE_SHIFT, 0);
+       nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
 
        /* big page (2M) range*/
        start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
@@ -706,37 +741,40 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
                         << (PUD_SHIFT - PAGE_SHIFT);
        if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
                end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
-       if (start_pfn < end_pfn)
-               last_map_addr = kernel_physical_mapping_init(
-                                            start_pfn<<PAGE_SHIFT,
-                                            end_pfn<<PAGE_SHIFT,
-                                            page_size_mask & (1<<PG_LEVEL_2M));
+       nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+                       page_size_mask & (1<<PG_LEVEL_2M));
 
        /* big page (1G) range */
        start_pfn = end_pfn;
        end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
-       if (start_pfn < end_pfn)
-               last_map_addr = kernel_physical_mapping_init(
-                                            start_pfn<<PAGE_SHIFT,
-                                            end_pfn<<PAGE_SHIFT,
-                                            page_size_mask & ((1<<PG_LEVEL_2M)
-                                                        | (1<<PG_LEVEL_1G)));
+       nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+                               page_size_mask &
+                                ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
 
        /* tail is not big page (1G) alignment */
        start_pfn = end_pfn;
        end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
-       if (start_pfn < end_pfn)
-               last_map_addr = kernel_physical_mapping_init(
-                                            start_pfn<<PAGE_SHIFT,
-                                            end_pfn<<PAGE_SHIFT,
-                                            page_size_mask & (1<<PG_LEVEL_2M));
+       nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+                       page_size_mask & (1<<PG_LEVEL_2M));
+
        /* tail is not big page (2M) alignment */
        start_pfn = end_pfn;
        end_pfn = end>>PAGE_SHIFT;
-       if (start_pfn < end_pfn)
+       nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
+
+       for (i = 0; i < nr_range; i++)
+               printk(KERN_DEBUG " %010lx - %010lx page %s\n",
+                               mr[i].start, mr[i].end,
+                       (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
+                        (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
+
+       if (!after_bootmem)
+               find_early_table_space(end);
+
+       for (i = 0; i < nr_range; i++)
                last_map_addr = kernel_physical_mapping_init(
-                                            start_pfn<<PAGE_SHIFT,
-                                            end_pfn<<PAGE_SHIFT, 0);
+                                       mr[i].start, mr[i].end,
+                                       mr[i].page_size_mask);
 
        if (!after_bootmem)
                mmu_cr4_features = read_cr4();