[kvm-unit-tests PATCH v3 0/1] s390x: add migration test for storage keys

[kvm-unit-tests PATCH v3 0/1] s390x: add migration test for storage keys

[Nico Boehr]

v2->v3:
----
* remove some useless variables, style suggestions, improve commit description
  (thanks Janis)
* reverse christmas tree (thanks Claudio)

v1->v2:
----
* As per discussion with Janis and Claudio, remove the actual access check from
  the test. This also allows us to remove the check_pgm_int_code_xfail() patch.
* Typos/Style suggestions (thanks Janis)

Upon migration, we expect storage keys set by the guest to be preserved,
so add a test for it.

We keep 128 pages and set predictable storage keys. Then, we migrate and check
they can be read back.

Nico Boehr (1):
  s390x: add migration test for storage keys

 s390x/Makefile         |  1 +
 s390x/migration-skey.c | 76 ++++++++++++++++++++++++++++++++++++++++++
 s390x/unittests.cfg    |  4 +++
 3 files changed, 81 insertions(+)
 create mode 100644 s390x/migration-skey.c

-- 
2.36.1

[kvm-unit-tests PATCH v3 1/1] s390x: add migration test for storage keys

[Nico Boehr]

Upon migration, we expect storage keys set by the guest to be preserved, so add
a test for it.

We keep 128 pages and set predictable storage keys. Then, we migrate and check
that they can be read back and match the value originally set.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---
 s390x/Makefile         |  1 +
 s390x/migration-skey.c | 76 ++++++++++++++++++++++++++++++++++++++++++
 s390x/unittests.cfg    |  4 +++
 3 files changed, 81 insertions(+)
 create mode 100644 s390x/migration-skey.c

diff --git a/s390x/Makefile b/s390x/Makefile
index 25802428fa13..94fc5c1a3527 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -33,6 +33,7 @@ tests += $(TEST_DIR)/adtl-status.elf
 tests += $(TEST_DIR)/migration.elf
 tests += $(TEST_DIR)/pv-attest.elf
 tests += $(TEST_DIR)/migration-cmm.elf
+tests += $(TEST_DIR)/migration-skey.elf
 
 pv-tests += $(TEST_DIR)/pv-diags.elf
 
diff --git a/s390x/migration-skey.c b/s390x/migration-skey.c
new file mode 100644
index 000000000000..f846ac435836
--- /dev/null
+++ b/s390x/migration-skey.c
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Storage Key migration tests
+ *
+ * Copyright IBM Corp. 2022
+ *
+ * Authors:
+ *  Nico Boehr <nrb@linux.ibm.com>
+ */
+
+#include <libcflat.h>
+#include <asm/facility.h>
+#include <asm/page.h>
+#include <asm/mem.h>
+#include <asm/interrupt.h>
+#include <hardware.h>
+
+#define NUM_PAGES 128
+static uint8_t pagebuf[NUM_PAGES][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+
+static void test_migration(void)
+{
+	union skey expected_key, actual_key;
+	int i, key_to_set;
+
+	for (i = 0; i < NUM_PAGES; i++) {
+		/*
+		 * Storage keys are 7 bit, lowest bit is always returned as zero
+		 * by iske
+		 */
+		key_to_set = i * 2;
+		set_storage_key(pagebuf[i], key_to_set, 1);
+	}
+
+	puts("Please migrate me, then press return\n");
+	(void)getchar();
+
+	for (i = 0; i < NUM_PAGES; i++) {
+		report_prefix_pushf("page %d", i);
+
+		actual_key.val = get_storage_key(pagebuf[i]);
+		expected_key.val = i * 2;
+
+		/* ignore reference bit */
+		actual_key.str.rf = 0;
+		expected_key.str.rf = 0;
+
+		report(actual_key.val == expected_key.val, "expected_key=0x%x actual_key=0x%x", expected_key.val, actual_key.val);
+
+		report_prefix_pop();
+	}
+}
+
+int main(void)
+{
+	report_prefix_push("migration-skey");
+	if (test_facility(169)) {
+		report_skip("storage key removal facility is active");
+
+		/*
+		 * If we just exit and don't ask migrate_cmd to migrate us, it
+		 * will just hang forever. Hence, also ask for migration when we
+		 * skip this test altogether.
+		 */
+		puts("Please migrate me, then press return\n");
+		(void)getchar();
+
+		goto done;
+	}
+
+	test_migration();
+
+done:
+	report_prefix_pop();
+	return report_summary();
+}
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index 9b97d0471bcf..8e52f560bb1e 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -180,3 +180,7 @@ smp = 2
 [migration-cmm]
 file = migration-cmm.elf
 groups = migration
+
+[migration-skey]
+file = migration-skey.elf
+groups = migration
-- 
2.36.1

Re: [kvm-unit-tests PATCH v3 1/1] s390x: add migration test for storage keys

[Thomas Huth]

On 31/05/2022 10.37, Nico Boehr wrote:
> Upon migration, we expect storage keys set by the guest to be preserved, so add
> a test for it.
> 
> We keep 128 pages and set predictable storage keys. Then, we migrate and check
> that they can be read back and match the value originally set.
> 
> Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> ---
>   s390x/Makefile         |  1 +
>   s390x/migration-skey.c | 76 ++++++++++++++++++++++++++++++++++++++++++
>   s390x/unittests.cfg    |  4 +++
>   3 files changed, 81 insertions(+)
>   create mode 100644 s390x/migration-skey.c
> 
> diff --git a/s390x/Makefile b/s390x/Makefile
> index 25802428fa13..94fc5c1a3527 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -33,6 +33,7 @@ tests += $(TEST_DIR)/adtl-status.elf
>   tests += $(TEST_DIR)/migration.elf
>   tests += $(TEST_DIR)/pv-attest.elf
>   tests += $(TEST_DIR)/migration-cmm.elf
> +tests += $(TEST_DIR)/migration-skey.elf
>   
>   pv-tests += $(TEST_DIR)/pv-diags.elf
>   
> diff --git a/s390x/migration-skey.c b/s390x/migration-skey.c
> new file mode 100644
> index 000000000000..f846ac435836
> --- /dev/null
> +++ b/s390x/migration-skey.c
> @@ -0,0 +1,76 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Storage Key migration tests
> + *
> + * Copyright IBM Corp. 2022
> + *
> + * Authors:
> + *  Nico Boehr <nrb@linux.ibm.com>
> + */
> +
> +#include <libcflat.h>
> +#include <asm/facility.h>
> +#include <asm/page.h>
> +#include <asm/mem.h>
> +#include <asm/interrupt.h>
> +#include <hardware.h>
> +
> +#define NUM_PAGES 128
> +static uint8_t pagebuf[NUM_PAGES][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
> +
> +static void test_migration(void)
> +{
> +	union skey expected_key, actual_key;
> +	int i, key_to_set;
> +
> +	for (i = 0; i < NUM_PAGES; i++) {
> +		/*
> +		 * Storage keys are 7 bit, lowest bit is always returned as zero
> +		 * by iske
> +		 */
> +		key_to_set = i * 2;
> +		set_storage_key(pagebuf[i], key_to_set, 1);
> +	}
> +
> +	puts("Please migrate me, then press return\n");
> +	(void)getchar();
> +
> +	for (i = 0; i < NUM_PAGES; i++) {
> +		report_prefix_pushf("page %d", i);
> +
> +		actual_key.val = get_storage_key(pagebuf[i]);
> +		expected_key.val = i * 2;
> +
> +		/* ignore reference bit */
> +		actual_key.str.rf = 0;
> +		expected_key.str.rf = 0;

If the reference bit gets always ignored, testing 64 pages should be enough? 
OTOH this will complicate the for-loop / creation of the key value, so I 
don't mind too much if we keep it this way.

> +		report(actual_key.val == expected_key.val, "expected_key=0x%x actual_key=0x%x", expected_key.val, actual_key.val);
> +
> +		report_prefix_pop();
> +	}
> +}
> +
> +int main(void)
> +{
> +	report_prefix_push("migration-skey");
> +	if (test_facility(169)) {
> +		report_skip("storage key removal facility is active");
> +
> +		/*
> +		 * If we just exit and don't ask migrate_cmd to migrate us, it
> +		 * will just hang forever. Hence, also ask for migration when we
> +		 * skip this test altogether.
> +		 */
> +		puts("Please migrate me, then press return\n");
> +		(void)getchar();
> +
> +		goto done;
> +	}
> +
> +	test_migration();
> +
> +done:

	} else {
		test_migration();
	}

to get rid of the goto?

> +	report_prefix_pop();
> +	return report_summary();
> +}

Either way:
Reviewed-by: Thomas Huth <thuth@redhat.com>

Re: [kvm-unit-tests PATCH v3 1/1] s390x: add migration test for storage keys

[Nico Boehr]

On Tue, 31 May 2022 10:55:27 +0200
Thomas Huth <thuth@redhat.com> wrote:

> On 31/05/2022 10.37, Nico Boehr wrote:
> > Upon migration, we expect storage keys set by the guest to be
> > preserved, so add a test for it.
> > 
> > We keep 128 pages and set predictable storage keys. Then, we
> > migrate and check that they can be read back and match the value
> > originally set.
> > 
> > Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
> > Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> > ---
> >   s390x/Makefile         |  1 +
> >   s390x/migration-skey.c | 76
> > ++++++++++++++++++++++++++++++++++++++++++ s390x/unittests.cfg    |
> >  4 +++ 3 files changed, 81 insertions(+)
> >   create mode 100644 s390x/migration-skey.c
> > 
> > diff --git a/s390x/Makefile b/s390x/Makefile
> > index 25802428fa13..94fc5c1a3527 100644
> > --- a/s390x/Makefile
> > +++ b/s390x/Makefile
> > @@ -33,6 +33,7 @@ tests += $(TEST_DIR)/adtl-status.elf
> >   tests += $(TEST_DIR)/migration.elf
> >   tests += $(TEST_DIR)/pv-attest.elf
> >   tests += $(TEST_DIR)/migration-cmm.elf
> > +tests += $(TEST_DIR)/migration-skey.elf
> >   
> >   pv-tests += $(TEST_DIR)/pv-diags.elf
> >   
> > diff --git a/s390x/migration-skey.c b/s390x/migration-skey.c
> > new file mode 100644
> > index 000000000000..f846ac435836
> > --- /dev/null
> > +++ b/s390x/migration-skey.c
> > @@ -0,0 +1,76 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Storage Key migration tests
> > + *
> > + * Copyright IBM Corp. 2022
> > + *
> > + * Authors:
> > + *  Nico Boehr <nrb@linux.ibm.com>
> > + */
> > +
> > +#include <libcflat.h>
> > +#include <asm/facility.h>
> > +#include <asm/page.h>
> > +#include <asm/mem.h>
> > +#include <asm/interrupt.h>
> > +#include <hardware.h>
> > +
> > +#define NUM_PAGES 128
> > +static uint8_t pagebuf[NUM_PAGES][PAGE_SIZE]
> > __attribute__((aligned(PAGE_SIZE))); +
> > +static void test_migration(void)
> > +{
> > +	union skey expected_key, actual_key;
> > +	int i, key_to_set;
> > +
> > +	for (i = 0; i < NUM_PAGES; i++) {
> > +		/*
> > +		 * Storage keys are 7 bit, lowest bit is always
> > returned as zero
> > +		 * by iske
> > +		 */
> > +		key_to_set = i * 2;
> > +		set_storage_key(pagebuf[i], key_to_set, 1);
> > +	}
> > +
> > +	puts("Please migrate me, then press return\n");
> > +	(void)getchar();
> > +
> > +	for (i = 0; i < NUM_PAGES; i++) {
> > +		report_prefix_pushf("page %d", i);
> > +
> > +		actual_key.val = get_storage_key(pagebuf[i]);
> > +		expected_key.val = i * 2;
> > +
> > +		/* ignore reference bit */
> > +		actual_key.str.rf = 0;
> > +		expected_key.str.rf = 0;  
> 
> If the reference bit gets always ignored, testing 64 pages should be
> enough? OTOH this will complicate the for-loop / creation of the key
> value, so I don't mind too much if we keep it this way.
> 
> > +		report(actual_key.val == expected_key.val,
> > "expected_key=0x%x actual_key=0x%x", expected_key.val,
> > actual_key.val); +
> > +		report_prefix_pop();
> > +	}
> > +}
> > +
> > +int main(void)
> > +{
> > +	report_prefix_push("migration-skey");
> > +	if (test_facility(169)) {
> > +		report_skip("storage key removal facility is
> > active"); +
> > +		/*
> > +		 * If we just exit and don't ask migrate_cmd to
> > migrate us, it
> > +		 * will just hang forever. Hence, also ask for
> > migration when we
> > +		 * skip this test altogether.
> > +		 */
> > +		puts("Please migrate me, then press return\n");
> > +		(void)getchar();
> > +
> > +		goto done;
> > +	}
> > +
> > +	test_migration();
> > +
> > +done:  
> 
> 	} else {
> 		test_migration();
> 	}
> 
> to get rid of the goto?
> 
> > +	report_prefix_pop();
> > +	return report_summary();
> > +}  
> 
> Either way:
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> 

Re: [kvm-unit-tests PATCH v3 1/1] s390x: add migration test for storage keys

[Nico Boehr]

Ooops, I just realized I accidentally sent an empty message this
morning. Sorry!

On Tue, 31 May 2022 10:55:27 +0200
Thomas Huth <thuth@redhat.com> wrote:

[...]
> > diff --git a/s390x/migration-skey.c b/s390x/migration-skey.c
> > new file mode 100644
> > index 000000000000..f846ac435836
> > --- /dev/null
> > +++ b/s390x/migration-skey.c
[...]
> > +	for (i = 0; i < NUM_PAGES; i++) {
> > +		report_prefix_pushf("page %d", i);
> > +
> > +		actual_key.val = get_storage_key(pagebuf[i]);
> > +		expected_key.val = i * 2;
> > +
> > +		/* ignore reference bit */
> > +		actual_key.str.rf = 0;
> > +		expected_key.str.rf = 0;  
> 
> If the reference bit gets always ignored, testing 64 pages should be
> enough? OTOH this will complicate the for-loop / creation of the key
> value, so I don't mind too much if we keep it this way.

Since it would make this thing more complex, I think I would just leave it as-is, 64 additional pages don't cost much.

[...]
> > +	if (test_facility(169)) {
> > +		report_skip("storage key removal facility is
> > active"); +
> > +		/*
> > +		 * If we just exit and don't ask migrate_cmd to
> > migrate us, it
> > +		 * will just hang forever. Hence, also ask for
> > migration when we
> > +		 * skip this test altogether.
> > +		 */
> > +		puts("Please migrate me, then press return\n");
> > +		(void)getchar();
> > +
> > +		goto done;
> > +	}
> > +
> > +	test_migration();
> > +
> > +done:  
> 
> 	} else {
> 		test_migration();
> 	}
> 
> to get rid of the goto?

Yes, makes sense, thank you.

[...]
> Either way:
> Reviewed-by: Thomas Huth <thuth@redhat.com>

Thanks.