When the pgtable is NULL in the set_huge_zero_page(), we should not increment the count of PTE page table pages by calling mm_inc_nr_ptes(). Otherwise we may receive the following warning when the mm exits: BUG: non-zero pgtables_bytes on freeing mm Now we can't observe the above warning since only do_huge_pmd_anonymous_page() invokes set_huge_zero_page() and the pgtable can not be NULL. Therefore, instead of moving mm_inc_nr_ptes() to the non-NULL branch of pgtable, it is better to remove the redundant pgtable check directly. Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> --- mm/huge_memory.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 83c47a989260..655da0b4fea0 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -770,8 +770,7 @@ static void set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm, return; entry = mk_pmd(zero_page, vma->vm_page_prot); entry = pmd_mkhuge(entry); - if (pgtable) - pgtable_trans_huge_deposit(mm, pmd, pgtable); + pgtable_trans_huge_deposit(mm, pmd, pgtable); set_pmd_at(mm, haddr, pmd, entry); mm_inc_nr_ptes(mm); } -- 2.20.1
