s390x: cmm: test no-translate bit after reset
KVM did not properly reset the no-translate bit after reset, see
https://lore.kernel.org/kvm/20231109123624.37314-1-imbrenda@linux.ibm.com/
Add a test which performs a load normal reset (includes a subsystem
reset) and verify that this clears the no-translate bit.
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20240423103529.313782-2-nrb@linux.ibm.com
Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
diff --git a/s390x/cmm.c b/s390x/cmm.c
index af85283..536f2bf 100644
--- a/s390x/cmm.c
+++ b/s390x/cmm.c
@@ -9,13 +9,17 @@
*/
#include <libcflat.h>
+#include <bitops.h>
#include <asm/asm-offsets.h>
#include <asm/interrupt.h>
#include <asm/page.h>
#include <asm/cmm.h>
+#include <asm/facility.h>
static uint8_t pagebuf[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+extern int diag308_load_reset(u64);
+
static void test_params(void)
{
report_prefix_push("invalid ORC 8");
@@ -35,6 +39,35 @@
report_prefix_pop();
}
+static void test_reset_no_translate(void)
+{
+ const uint64_t mask_no_translate = BIT(63 - 58);
+ unsigned long state;
+
+ if (!test_facility(147)) {
+ report_prefix_push("no-translate unavailable");
+ expect_pgm_int();
+ essa(ESSA_SET_STABLE_NODAT, (unsigned long)pagebuf);
+ check_pgm_int_code(PGM_INT_CODE_SPECIFICATION);
+ report_prefix_pop();
+ return;
+ }
+
+ report_prefix_push("reset no-translate");
+ essa(ESSA_SET_STABLE_NODAT, (unsigned long)pagebuf);
+
+ state = essa(ESSA_GET_STATE, (unsigned long)pagebuf);
+ report(state & mask_no_translate, "no-translate bit set before reset");
+
+ /* Load normal reset - includes subsystem reset */
+ diag308_load_reset(1);
+
+ state = essa(ESSA_GET_STATE, (unsigned long)pagebuf);
+ report(!(state & mask_no_translate), "no-translate bit unset after reset");
+
+ report_prefix_pop();
+}
+
int main(void)
{
bool has_essa = check_essa_available();
@@ -47,6 +80,7 @@
test_priv();
test_params();
+ test_reset_no_translate();
done:
report_prefix_pop();
return report_summary();
