[PATCH 2/6] hugetlbfs: fix cannot migrate the fallocated HugeTLB page

From: Muchun Song
Date: Mon Jan 04 2021 - 02:02:22 EST


Because we only can isolate a active page via isolate_huge_page()
and hugetlbfs_fallocate() forget to mark it as active, we cannot
isolate and migrate those pages.

Fixes: 70c3547e36f5 (hugetlbfs: add hugetlbfs_fallocate())
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
fs/hugetlbfs/inode.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index b5c109703daa..2aceb085d202 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -737,10 +737,11 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,

/*
* unlock_page because locked by add_to_page_cache()
- * page_put due to reference from alloc_huge_page()
+ * put_page() (which is in the putback_active_hugepage())
+ * due to reference from alloc_huge_page()
*/
unlock_page(page);
- put_page(page);
+ putback_active_hugepage(page);
}

if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > inode->i_size)
--
2.11.0