diff options
| -rw-r--r-- | arch/x86/mm/init_32.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 322ee56ea1fe..19ef9f018012 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -480,9 +480,14 @@ void __init native_pagetable_init(void) /* * Remove any mappings which extend past the end of physical - * memory from the boot time page table: + * memory from the boot time page table. + * In virtual address space, we should have at least two pages + * from VMALLOC_END to pkmap or fixmap according to VMALLOC_END + * definition. And max_low_pfn is set to VMALLOC_END physical + * address. If initial memory mapping is doing right job, we + * should have pte used near max_low_pfn or one pmd is not present. */ - for (pfn = max_low_pfn + 1; pfn < 1<<(32-PAGE_SHIFT); pfn++) { + for (pfn = max_low_pfn; pfn < 1<<(32-PAGE_SHIFT); pfn++) { va = PAGE_OFFSET + (pfn<<PAGE_SHIFT); pgd = base + pgd_index(va); if (!pgd_present(*pgd)) @@ -493,10 +498,19 @@ void __init native_pagetable_init(void) if (!pmd_present(*pmd)) break; + /* should not be large page here */ + if (pmd_large(*pmd)) { + pr_warn("try to clear pte for ram above max_low_pfn: pfn: %lx pmd: %p pmd phys: %lx, but pmd is big page and is not using pte !\n", + pfn, pmd, __pa(pmd)); + BUG_ON(1); + } + pte = pte_offset_kernel(pmd, va); if (!pte_present(*pte)) break; + printk(KERN_DEBUG "clearing pte for ram above max_low_pfn: pfn: %lx pmd: %p pmd phys: %lx pte: %p pte phys: %lx\n", + pfn, pmd, __pa(pmd), pte, __pa(pte)); pte_clear(NULL, va, pte); } paravirt_alloc_pmd(&init_mm, __pa(base) >> PAGE_SHIFT); |
