[kvm-unit-tests PATCH v1 2/2] s390x: add cmm migration test

Nico Boehr
2022-05-09T12:08:16Z

When a VM is migrated, we expect the page states to be preserved. Add a test
which checks for that.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
---
s390x/Makefile | 1 +
s390x/cmm-migration.c | 78 +++++++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 4 +++
3 files changed, 83 insertions(+)
create mode 100644 s390x/cmm-migration.c

diff --git a/s390x/Makefile b/s390x/Makefile
index a8e04aa6fe4d..8ac0afdfd994 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -32,6 +32,7 @@ tests += $(TEST_DIR)/epsw.elf
tests += $(TEST_DIR)/adtl-status.elf
tests += $(TEST_DIR)/migration.elf
tests += $(TEST_DIR)/pv-attest.elf
+tests += $(TEST_DIR)/cmm-migration.elf

pv-tests += $(TEST_DIR)/pv-diags.elf

diff --git a/s390x/cmm-migration.c b/s390x/cmm-migration.c
new file mode 100644
index 000000000000..4a7b50e40fc6
--- /dev/null
+++ b/s390x/cmm-migration.c
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * CMM migration tests (ESSA)
+ *
+ * Copyright IBM Corp. 2022
+ *
+ * Authors:
+ * Nico Boehr <nrb@linux.ibm.com>
+ */
+
+#include <libcflat.h>
+#include <asm/asm-offsets.h>
+#include <asm/interrupt.h>
+#include <asm/page.h>
+#include <asm/cmm.h>
+#include <bitops.h>
+
+#define NUM_PAGES 128
+static uint8_t pagebuf[NUM_PAGES][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+
+static void test_migration(void)
+{
+ int i, state_mask, actual_state;
+ /*
+ * Maps ESSA actions to states the page is allowed to be in after the
+ * respective action was executed.
+ */
+ int allowed_essa_state_masks[4] = {
+ BIT(ESSA_USAGE_STABLE), /* ESSA_SET_STABLE */
+ BIT(ESSA_USAGE_UNUSED), /* ESSA_SET_UNUSED */
+ BIT(ESSA_USAGE_VOLATILE), /* ESSA_SET_VOLATILE */
+ BIT(ESSA_USAGE_VOLATILE) | BIT(ESSA_USAGE_POT_VOLATILE) /* ESSA_SET_POT_VOLATILE */
+ };
+
+ for (i = 0; i < NUM_PAGES; i++) {
+ switch(i % 4) {
+ case 0:
+ essa(ESSA_SET_STABLE, (unsigned long)pagebuf[i]);
+ break;
+ case 1:
+ essa(ESSA_SET_UNUSED, (unsigned long)pagebuf[i]);
+ break;
+ case 2:
+ essa(ESSA_SET_VOLATILE, (unsigned long)pagebuf[i]);
+ break;
+ case 3:
+ essa(ESSA_SET_POT_VOLATILE, (unsigned long)pagebuf[i]);
+ break;
+ }
+ }
+
+ puts("Please migrate me, then press return\n");
+ (void)getchar();
+
+ for (i = 0; i < NUM_PAGES; i++) {
+ actual_state = essa(ESSA_GET_STATE, (unsigned long)pagebuf[i]);
+ /* extract the usage state in bits 60 and 61 */
+ actual_state = (actual_state >> 2) & 0x3;
+ state_mask = allowed_essa_state_masks[i % ARRAY_SIZE(allowed_essa_state_masks)];
+ report(BIT(actual_state) & state_mask, "page %d state: expected_mask=0x%x actual_mask=0x%lx", i, state_mask, BIT(actual_state));
+ }
+}
+
+int main(void)
+{
+ bool has_essa = check_essa_available();
+
+ report_prefix_push("cmm-migration");
+ if (!has_essa) {
+ report_skip("ESSA is not available");
+ goto done;
+ }
+
+ test_migration();
+done:
+ report_prefix_pop();
+ return report_summary();
+}
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index b456b2881448..625026d90e52 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -176,3 +176,7 @@ extra_params = -cpu qemu,gs=off,vx=off
file = migration.elf
groups = migration
smp = 2
+
+[cmm-migration]
+file = cmm-migration.elf
+groups = migration
--
2.31.1