[PATCH 3/5] selftests/sgx: Ensure correct secinfo struct alignment in test enclave.

[Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>]

Declare the secinfo struct as volatile to prevent compiler optimizations
from passing an unaligned pointer to ENCLU.

Signed-off-by: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
---
 tools/testing/selftests/sgx/test_encl.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c
index 4e31a6c3d673..aba301abefb8 100644
--- a/tools/testing/selftests/sgx/test_encl.c
+++ b/tools/testing/selftests/sgx/test_encl.c
@@ -18,7 +18,8 @@ enum sgx_enclu_function {
 
 static void do_encl_emodpe(void *_op)
 {
-	struct sgx_secinfo secinfo __aligned(sizeof(struct sgx_secinfo)) = {0};
+	/* declare secinfo volatile to preserve alignment */
+	volatile struct sgx_secinfo secinfo __aligned(sizeof(struct sgx_secinfo)) = {0};
 	struct encl_op_emodpe *op = _op;
 
 	secinfo.flags = op->flags;
@@ -32,7 +33,8 @@ static void do_encl_emodpe(void *_op)
 
 static void do_encl_eaccept(void *_op)
 {
-	struct sgx_secinfo secinfo __aligned(sizeof(struct sgx_secinfo)) = {0};
+	/* declare secinfo volatile to preserve alignment */
+	volatile struct sgx_secinfo secinfo __aligned(sizeof(struct sgx_secinfo)) = {0};
 	struct encl_op_eaccept *op = _op;
 	int rax;
 
-- 
2.34.1