[LTP] [PATCH v1] shmget02: check if CONFIG_HUGETLBFS enabled in kernel

[Bogdan Lezhepekov]

Two tests call shmget with a flag SHM_HUGETLB, trying to
allocate the segment using "huge" pages. The hugetlbpage
support needs to be enabled in kernel (CONFIG_HUGETLBFS),
otherwise shmget returns EINVAL.

Signed-off-by: Bogdan Lezhepekov <bogdan.lezhepekov@suse.com>
---
 .../kernel/syscalls/ipc/shmget/shmget02.c     | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/testcases/kernel/syscalls/ipc/shmget/shmget02.c b/testcases/kernel/syscalls/ipc/shmget/shmget02.c
index 66a4b94ee..4d515fb81 100644
--- a/testcases/kernel/syscalls/ipc/shmget/shmget02.c
+++ b/testcases/kernel/syscalls/ipc/shmget/shmget02.c
@@ -32,10 +32,13 @@
 #include <sys/shm.h>
 #include <grp.h>
 #include "tst_safe_sysv_ipc.h"
+#include "tst_kconfig.h"
 #include "tst_test.h"
 #include "libnewipc.h"
 #include "lapi/shm.h"
 
+#define CONFIG_HUGETLBFS "CONFIG_HUGETLBFS"
+
 static int shm_id = -1;
 static key_t shmkey, shmkey1;
 static struct passwd *pw;
@@ -60,11 +63,29 @@ static struct tcase {
 	{&shmkey1, SHM_SIZE, IPC_CREAT | SHM_HUGETLB, 0, 0, ENOMEM}
 };
 
+inline static int hugetlbfs_enabled()
+{
+	struct tst_kconfig_var kconfig = {
+		.id = CONFIG_HUGETLBFS,
+		.id_len = sizeof(CONFIG_HUGETLBFS)-1,
+	};
+
+	tst_kconfig_read(&kconfig, 1);
+	return kconfig.choice == 'y';
+}
+
 static void do_test(unsigned int n)
 {
 	struct tcase *tc = &tcases[n];
 	pid_t pid;
 
+	if (((tc->flags & SHM_HUGETLB) == SHM_HUGETLB) && ! hugetlbfs_enabled())
+	{
+		tst_brk(TCONF,
+			"Unsuitable kernel config: CONFIG_HUGETLBFS missing");
+		return;
+	}
+
 	if (tc->exp_user == 0 && tc->exp_group == 0) {
 		TST_EXP_FAIL2(shmget(*tc->shmkey, tc->size, tc->flags), tc->exp_err,
 			"shmget(%i, %lu, %i)", *tc->shmkey, tc->size, tc->flags);
-- 
2.32.0