From 0b34dca1bfd5eb98e8a2e84aa5ed0d137450562a Mon Sep 17 00:00:00 2001
From: Terry Tritton <terry.tritton@linaro.org>
Date: Mon, 5 Feb 2024 14:50:56 +0000
Subject: [PATCH] selftests/mm: uffd-unit-test check if huge page size is 0

commit 7efa6f2c803366f84c3c362f01e822490669d72b upstream.

If HUGETLBFS is not enabled then the default_huge_page_size function will
return 0 and cause a divide by 0 error. Add a check to see if the huge page
size is 0 and skip the hugetlb tests if it is.

Link: https://lkml.kernel.org/r/20240205145055.3545806-2-terry.tritton@linaro.org
Fixes: 16a45b57cbf2 ("selftests/mm: add framework for uffd-unit-test")
Signed-off-by: Terry Tritton <terry.tritton@linaro.org>
Cc: Peter Griffin <peter.griffin@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 tools/testing/selftests/mm/uffd-unit-tests.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
index 2709a34a39c5..2c68709062da 100644
--- a/tools/testing/selftests/mm/uffd-unit-tests.c
+++ b/tools/testing/selftests/mm/uffd-unit-tests.c
@@ -1309,6 +1309,12 @@ int main(int argc, char *argv[])
 				continue;
 
 			uffd_test_start("%s on %s", test->name, mem_type->name);
+			if ((mem_type->mem_flag == MEM_HUGETLB ||
+			    mem_type->mem_flag == MEM_HUGETLB_PRIVATE) &&
+			    (default_huge_page_size() == 0)) {
+				uffd_test_skip("huge page size is 0, feature missing?");
+				continue;
+			}
 			if (!uffd_feature_supported(test)) {
 				uffd_test_skip("feature missing");
 				continue;