[PATCH v2 0/2] Skip mm selftests instead when kernel features are not present

[PATCH v2 0/2] Skip mm selftests instead when kernel features are not present

[Zi Yan]

Two guard_regions tests on userfaultfd fail when userfaultfd is not
present. Skip them instead.

hugevm test reads kernel config to get page table level information and
fails when neither /proc/config.gz nor /boot/config-* is present. Skip
it instead.

Zi Yan (2):
  selftests/mm: skip guard_regions.uffd tests when uffd is not present.
  selftests/mm: skip hugevm test if kernel config file is not present.

 tools/testing/selftests/mm/guard-regions.c    | 17 ++++++++++--
 .../selftests/mm/va_high_addr_switch.sh       | 26 +++++++------------
 2 files changed, 24 insertions(+), 19 deletions(-)

-- 
2.47.2

[PATCH v2 1/2] selftests/mm: skip guard_regions.uffd tests when uffd is not present.

[Zi Yan]

When userfaultfd is not compiled into kernel, userfaultfd() returns -1,
causing guard_regions.uffd tests to fail. Skip the tests instead.

Signed-off-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
---
 tools/testing/selftests/mm/guard-regions.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/selftests/mm/guard-regions.c
index 0cd9d236649d..93af3d3760f9 100644
--- a/tools/testing/selftests/mm/guard-regions.c
+++ b/tools/testing/selftests/mm/guard-regions.c
@@ -1453,8 +1453,21 @@ TEST_F(guard_regions, uffd)
 
 	/* Set up uffd. */
 	uffd = userfaultfd(0);
-	if (uffd == -1 && errno == EPERM)
-		ksft_exit_skip("No userfaultfd permissions, try running as root.\n");
+	if (uffd == -1) {
+		switch (errno) {
+		case EPERM:
+			SKIP(return, "No userfaultfd permissions, try running as root.");
+			break;
+		case ENOSYS:
+			SKIP(return, "userfaultfd is not supported/not enabled.");
+			break;
+		default:
+			ksft_exit_fail_msg("userfaultfd failed with %s\n",
+					   strerror(errno));
+			break;
+		}
+	}
+
 	ASSERT_NE(uffd, -1);
 
 	ASSERT_EQ(ioctl(uffd, UFFDIO_API, &api), 0);
-- 
2.47.2

[PATCH v2 2/2] selftests/mm: skip hugevm test if kernel config file is not present.

[Zi Yan]

When running hugevm tests in a machine without kernel config present, e.g.,
a VM running a kernel without CONFIG_IKCONFIG_PROC nor /boot/config-*,
skip hugevm tests, which reads kernel config to get page table level
information.

Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
---
 .../selftests/mm/va_high_addr_switch.sh       | 26 +++++++------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/tools/testing/selftests/mm/va_high_addr_switch.sh b/tools/testing/selftests/mm/va_high_addr_switch.sh
index 1f92e8caceac..325de53966b6 100755
--- a/tools/testing/selftests/mm/va_high_addr_switch.sh
+++ b/tools/testing/selftests/mm/va_high_addr_switch.sh
@@ -7,23 +7,20 @@
 # real test to check that the kernel is configured to support at least 5
 # pagetable levels.
 
-# 1 means the test failed
-exitcode=1
-
 # Kselftest framework requirement - SKIP code is 4.
 ksft_skip=4
 
-fail()
+skip()
 {
 	echo "$1"
-	exit $exitcode
+	exit $ksft_skip
 }
 
 check_supported_x86_64()
 {
 	local config="/proc/config.gz"
 	[[ -f "${config}" ]] || config="/boot/config-$(uname -r)"
-	[[ -f "${config}" ]] || fail "Cannot find kernel config in /proc or /boot"
+	[[ -f "${config}" ]] || skip "Cannot find kernel config in /proc or /boot"
 
 	# gzip -dcfq automatically handles both compressed and plaintext input.
 	# See man 1 gzip under '-f'.
@@ -33,11 +30,9 @@ check_supported_x86_64()
 		else {print 1}; exit}' /proc/cpuinfo 2>/dev/null)
 
 	if [[ "${pg_table_levels}" -lt 5 ]]; then
-		echo "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
-		exit $ksft_skip
+		skip "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
 	elif [[ "${cpu_supports_pl5}" -ne 0 ]]; then
-		echo "$0: CPU does not have the necessary la57 flag to support page table level 5"
-		exit $ksft_skip
+		skip "$0: CPU does not have the necessary la57 flag to support page table level 5"
 	fi
 }
 
@@ -45,24 +40,21 @@ check_supported_ppc64()
 {
 	local config="/proc/config.gz"
 	[[ -f "${config}" ]] || config="/boot/config-$(uname -r)"
-	[[ -f "${config}" ]] || fail "Cannot find kernel config in /proc or /boot"
+	[[ -f "${config}" ]] || skip "Cannot find kernel config in /proc or /boot"
 
 	local pg_table_levels=$(gzip -dcfq "${config}" | grep PGTABLE_LEVELS | cut -d'=' -f 2)
 	if [[ "${pg_table_levels}" -lt 5 ]]; then
-		echo "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
-		exit $ksft_skip
+		skip "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
 	fi
 
 	local mmu_support=$(grep -m1 "mmu" /proc/cpuinfo | awk '{print $3}')
 	if [[ "$mmu_support" != "radix" ]]; then
-		echo "$0: System does not use Radix MMU, required for 5-level paging"
-		exit $ksft_skip
+		skip "$0: System does not use Radix MMU, required for 5-level paging"
 	fi
 
 	local hugepages_total=$(awk '/HugePages_Total/ {print $2}' /proc/meminfo)
 	if [[ "${hugepages_total}" -eq 0 ]]; then
-		echo "$0: HugePages are not enabled, required for some tests"
-		exit $ksft_skip
+		skip "$0: HugePages are not enabled, required for some tests"
 	fi
 }
 
-- 
2.47.2