Messages in this thread Patch in this message | | | From | Miaohe Lin <> | Subject | [PATCH v3 2/8] mm/memory-failure.c: catch unexpected -EFAULT from vma_address() | Date | Fri, 18 Feb 2022 17:01:12 +0800 |
| |
It's unexpected to walk the page table when vma_address() return -EFAULT. But dev_pagemap_mapping_shift() is called only when vma associated to the error page is found already in collect_procs_{file,anon}, so vma_address() should not return -EFAULT except with some bug, as Naoya pointed out. We can use VM_BUG_ON_VMA() to catch this bug here.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> --- mm/memory-failure.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b3ff7e99a421..eaa241058401 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -315,6 +315,7 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, pmd_t *pmd; pte_t *pte; + VM_BUG_ON_VMA(address == -EFAULT, vma); pgd = pgd_offset(vma->vm_mm, address); if (!pgd_present(*pgd)) return 0; -- 2.23.0
| |