[PATCH] mm/hugetlbfs: fix for_each_hstate() loop in init_hugetlbfs_fs()

From: Jan Stancek
Date: Fri Jan 03 2020 - 12:37:42 EST


LTP memfd_create04 started failing for some huge page sizes
after v5.4-10135-gc3bfc5dd73c6.

Problem is check introduced to for_each_hstate() loop that should
skip default_hstate_idx. Since it doesn't update 'i' counter, all
subsequent huge page sizes are skipped as well.

Fixes: 8fc312b32b25 ("mm/hugetlbfs: fix error handling when setting up mounts")
Signed-off-by: Jan Stancek <jstancek@xxxxxxxxxx>
---
fs/hugetlbfs/inode.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index d5c2a3158610..a66e425884d1 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1498,8 +1498,10 @@ static int __init init_hugetlbfs_fs(void)
/* other hstates are optional */
i = 0;
for_each_hstate(h) {
- if (i == default_hstate_idx)
+ if (i == default_hstate_idx) {
+ i++;
continue;
+ }

mnt = mount_one_hugetlbfs(h);
if (IS_ERR(mnt))
--
1.8.3.1