diff --git a/tests/testlib/s2n_ktls_test_utils.c b/tests/testlib/s2n_ktls_test_utils.c
index 3dc84dbc363..b38966f0ac7 100644
--- a/tests/testlib/s2n_ktls_test_utils.c
+++ b/tests/testlib/s2n_ktls_test_utils.c
@@ -62,6 +62,9 @@ ssize_t s2n_test_ktls_sendmsg_io_stuffer(void *io_context, const struct msghdr *
         size_t len = msg->msg_iov[count].iov_len;
 
         if (s2n_stuffer_write_bytes(data_buffer, buf, len) != S2N_SUCCESS) {
+            fprintf(stderr, "Stuffer write of %li@%li failed with %s / %s\n",
+                    (uintptr_t) buf, len,
+                    s2n_strerror(s2n_errno, NULL), s2n_strerror_debug(s2n_errno, NULL));
             size_t partial_len = MIN(len, s2n_stuffer_space_remaining(data_buffer));
             POSIX_GUARD(s2n_stuffer_write_bytes(data_buffer, buf, partial_len));
             total_len += partial_len;
diff --git a/tests/unit/s2n_ktls_io_test.c b/tests/unit/s2n_ktls_io_test.c
index 7de62ef4e5d..89f0347ff60 100644
--- a/tests/unit/s2n_ktls_io_test.c
+++ b/tests/unit/s2n_ktls_io_test.c
@@ -23,6 +23,8 @@
 #define S2N_TEST_TO_SEND    10
 #define S2N_TEST_MSG_IOVLEN 5
 
+extern s2n_ktls_sendmsg_fn s2n_sendmsg_fn;
+
 S2N_RESULT s2n_ktls_set_control_data(struct msghdr *msg, char *buf, size_t buf_size,
         int cmsg_type, uint8_t record_type);
 S2N_RESULT s2n_ktls_get_control_data(struct msghdr *msg, int cmsg_type, uint8_t *record_type);
@@ -825,6 +827,17 @@ int main(int argc, char **argv)
                 s2n_blocked_status blocked = S2N_NOT_BLOCKED;
                 ssize_t result = s2n_ktls_sendv_with_offset(conn,
                         test_iovecs.iovecs, test_iovecs.iovecs_count, offset, &blocked);
+                fprintf(stderr, "%li result = %li\n", offset, result);
+                fprintf(stderr, "%li sendmsg_fn=%li conn.io_context=%li out=%li\n", offset,
+                        (uintptr_t) s2n_sendmsg_fn, (uintptr_t) conn->send_io_context, (uintptr_t) &out);
+                fprintf(stderr, "%li control.growable=%i data.growable=%i "
+                        "data.allocated=%i data.write_cursor=%i "
+                        "data.read_cursor=%i\n", offset,
+                        out.ancillary_buffer.growable,
+                        out.data_buffer.growable,
+                        out.data_buffer.blob.allocated,
+                        out.data_buffer.write_cursor,
+                        out.data_buffer.read_cursor);
                 EXPECT_EQUAL(result, expected_sent);
 
                 EXPECT_EQUAL(out.sendmsg_invoked_count, 1);