diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 46 |
1 files changed, 26 insertions, 20 deletions
diff --git a/mm/memory.c b/mm/memory.c index 99e9f928264a..81dca0083fcd 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -563,8 +563,7 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma, } } -int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, - pmd_t *pmd, unsigned long address) +int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address) { spinlock_t *ptl; pgtable_t new = pte_alloc_one(mm, address); @@ -662,9 +661,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, return; } if (nr_unshown) { - printk(KERN_ALERT - "BUG: Bad page map: %lu messages suppressed\n", - nr_unshown); + pr_alert("BUG: Bad page map: %lu messages suppressed\n", + nr_unshown); nr_unshown = 0; } nr_shown = 0; @@ -675,15 +673,13 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, mapping = vma->vm_file ? vma->vm_file->f_mapping : NULL; index = linear_page_index(vma, addr); - printk(KERN_ALERT - "BUG: Bad page map in process %s pte:%08llx pmd:%08llx\n", - current->comm, - (long long)pte_val(pte), (long long)pmd_val(*pmd)); + pr_alert("BUG: Bad page map in process %s pte:%08llx pmd:%08llx\n", + current->comm, + (long long)pte_val(pte), (long long)pmd_val(*pmd)); if (page) dump_page(page, "bad pte"); - printk(KERN_ALERT - "addr:%p vm_flags:%08lx anon_vma:%p mapping:%p index:%lx\n", - (void *)addr, vma->vm_flags, vma->anon_vma, mapping, index); + pr_alert("addr:%p vm_flags:%08lx anon_vma:%p mapping:%p index:%lx\n", + (void *)addr, vma->vm_flags, vma->anon_vma, mapping, index); /* * Choose text because data symbols depend on CONFIG_KALLSYMS_ALL=y */ @@ -1898,7 +1894,9 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr, unsigned long end = addr + size; int err; - BUG_ON(addr >= end); + if (WARN_ON(addr >= end)) + return -EINVAL; + pgd = pgd_offset(mm, addr); do { next = pgd_addr_end(addr, end); @@ -3144,8 +3142,7 @@ static int do_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, pte_t *page_table, pmd_t *pmd, unsigned int flags, pte_t orig_pte) { - pgoff_t pgoff = (((address & PAGE_MASK) - - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; + pgoff_t pgoff = linear_page_index(vma, address); pte_unmap(page_table); /* The VMA was not fully populated on mmap() or missing VM_DONTEXPAND */ @@ -3424,15 +3421,24 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, } /* - * Use __pte_alloc instead of pte_alloc_map, because we can't + * Use pte_alloc() instead of pte_alloc_map, because we can't * run pte_offset_map on the pmd, if an huge pmd could * materialize from under us from a different thread. */ - if (unlikely(pmd_none(*pmd)) && - unlikely(__pte_alloc(mm, vma, pmd, address))) + if (unlikely(pte_alloc(mm, pmd, address))) return VM_FAULT_OOM; - /* if an huge pmd materialized from under us just retry later */ - if (unlikely(pmd_trans_huge(*pmd) || pmd_devmap(*pmd))) + /* + * If a huge pmd materialized under us just retry later. Use + * pmd_trans_unstable() instead of pmd_trans_huge() to ensure the pmd + * didn't become pmd_trans_huge under us and then back to pmd_none, as + * a result of MADV_DONTNEED running immediately after a huge pmd fault + * in a different thread of this mm, in turn leading to a misleading + * pmd_trans_huge() retval. All we have to ensure is that it is a + * regular pmd that we can walk with pte_offset_map() and we can do that + * through an atomic read in C, which is what pmd_trans_unstable() + * provides. + */ + if (unlikely(pmd_trans_unstable(pmd) || pmd_devmap(*pmd))) return 0; /* * A regular pmd is established and it can't morph into a huge pmd |