[kvm-unit-tests PATCH v3] s390x: diag308: Only test subcode 2 under QEMU

[Janosch Frank <frankja@linux.ibm.com>]

Other hypervisors might implement it and therefore not send a
specification exception.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 s390x/diag308.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/s390x/diag308.c b/s390x/diag308.c
index c9d6c499..ea41b455 100644
--- a/s390x/diag308.c
+++ b/s390x/diag308.c
@@ -8,6 +8,7 @@
 #include <libcflat.h>
 #include <asm/asm-offsets.h>
 #include <asm/interrupt.h>
+#include <hardware.h>
 
 /* The diagnose calls should be blocked in problem state */
 static void test_priv(void)
@@ -75,7 +76,7 @@ static void test_subcode6(void)
 /* Unsupported subcodes should generate a specification exception */
 static void test_unsupported_subcode(void)
 {
-	int subcodes[] = { 2, 0x101, 0xffff, 0x10001, -1 };
+	int subcodes[] = { 0x101, 0xffff, 0x10001, -1 };
 	int idx;
 
 	for (idx = 0; idx < ARRAY_SIZE(subcodes); idx++) {
@@ -85,6 +86,21 @@ static void test_unsupported_subcode(void)
 		check_pgm_int_code(PGM_INT_CODE_SPECIFICATION);
 		report_prefix_pop();
 	}
+
+	/*
+	 * Subcode 2 is not available under QEMU but might be on other
+	 * hypervisors so we only check for the specification
+	 * exception on QEMU.
+	 */
+	report_prefix_pushf("0x%04x", 2);
+	if (host_is_qemu()) {
+		expect_pgm_int();
+		asm volatile ("diag %0,%1,0x308" :: "d"(0), "d"(2));
+		check_pgm_int_code(PGM_INT_CODE_SPECIFICATION);
+	} else {
+		report_skip("subcode is supported");
+	}
+	report_prefix_pop();
 }
 
 static struct {
-- 
2.32.0