mm/hugetlb: fix missing call to restore_reserve_on_error()

When huge_add_to_page_cache() fails, the page is freed directly without
calling restore_reserve_on_error() to restore reserve for newly allocated
pages not in page cache.  Fix this by calling restore_reserve_on_error()
when huge_add_to_page_cache fails.

Link: https://lkml.kernel.org/r/20220816130553.31406-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ff991e5bdf1fab8f8578dc1daf8c417423815849..b69d7808f4579cc7683b139b2a0470bc7dc29426 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5603,6 +5603,7 @@ retry:
                if (vma->vm_flags & VM_MAYSHARE) {
                        int err = huge_add_to_page_cache(page, mapping, idx);
                        if (err) {
+                               restore_reserve_on_error(h, vma, haddr, page);
                                put_page(page);
                                if (err == -EEXIST)
                                        goto retry;