hugetlb: fix an error code in hugetlb_reserve_pages()

stable inclusion
from stable-5.10.4
commit 9b52a37fb348a9fadfe922652d0e627d53cb087f
bugzilla: 46903

--------------------------------

[ Upstream commit 7fc2513a ]

Preserve the error code from region_add() instead of returning success.

Link: https://lkml.kernel.org/r/X9NGZWnZl5/Mt99R@mwanda
Fixes: 0db9d74e ("hugetlb: disable region_add file_region coalescing")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NMike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

mm/hugetlb.c

@@ -5115,6 +5115,7 @@ int hugetlb_reserve_pages(struct inode *inode,
 
 		if (unlikely(add < 0)) {
 			hugetlb_acct_memory(h, -gbl_reserve);
+			ret = add;
 			goto out_put_pages;
 		} else if (unlikely(chg > add)) {
 			/*