| Message ID | 20210429132648.305447-6-linmiaohe@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Cleanup and fixup for huge_memory | expand |
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index af30338ac49c..87b0241394f4 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1607,7 +1607,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, * If other processes are mapping this page, we couldn't discard * the page unless they all do MADV_FREE so let's skip the page. */ - if (page_mapcount(page) != 1) + if (total_mapcount(page) != 1) goto out; if (!trylock_page(page))
If other processes are mapping any other subpages of the hugepage, i.e. in pte-mapped thp case, page_mapcount() will return 1 incorrectly. Then we would discard the page while other processes are still mapping it. Fix it by using total_mapcount() which can tell whether other processes are still mapping it. Fixes: b8d3c4c3009d ("mm/huge_memory.c: don't split THP page when MADV_FREE syscall is called") Reviewed-by: Yang Shi <shy828301@gmail.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> --- mm/huge_memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)