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.
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/hugetlb.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index d46dfe5ba62c..8e62da153c64 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5576,7 +5576,6 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
if (idx >= size)
goto out;
-retry:
new_page = false;
page = find_lock_page(mapping, idx);
if (!page) {
@@ -5616,9 +5615,15 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
if (vma->vm_flags & VM_MAYSHARE) {
int err = huge_add_to_page_cache(page, mapping, idx);
if (err) {
+ /*
+ * err can't be -EEXIST which implies someone
+ * else consumed the reservation since hugetlb
+ * fault mutex is held when add a hugetlb page
+ * to the page cache. So it's safe to call
+ * restore_reserve_on_error() here.
+ */
+ restore_reserve_on_error(h, vma, haddr, page);
put_page(page);
- if (err == -EEXIST)
- goto retry;
goto out;
}
new_pagecache_page = true;
--
2.23.0
