[PATCH/RFC] KVM: selftests: introduce P44V64 for z196 and EC12

[Christian Borntraeger <borntraeger@de.ibm.com>]

Older machines likes z196 and zEC12 do only support 44 bits of physical
addresses. Make this the default and check via IBC if we are on a later
machine. We then add P47V64 as an additional model.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Fixes: 1bc603af73dd ("KVM: selftests: introduce P47V64 for s390x")
---
 tools/testing/selftests/kvm/include/kvm_util.h |  3 ++-
 tools/testing/selftests/kvm/lib/guest_modes.c  | 16 ++++++++++++++++
 tools/testing/selftests/kvm/lib/kvm_util.c     |  5 +++++
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 35739567189e..74d73532fce9 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -44,6 +44,7 @@ enum vm_guest_mode {
 	VM_MODE_P40V48_64K,
 	VM_MODE_PXXV48_4K,	/* For 48bits VA but ANY bits PA */
 	VM_MODE_P47V64_4K,
+	VM_MODE_P44V64_4K,
 	NUM_VM_MODES,
 };
 
@@ -61,7 +62,7 @@ enum vm_guest_mode {
 
 #elif defined(__s390x__)
 
-#define VM_MODE_DEFAULT			VM_MODE_P47V64_4K
+#define VM_MODE_DEFAULT			VM_MODE_P44V64_4K
 #define MIN_PAGE_SHIFT			12U
 #define ptes_per_page(page_size)	((page_size) / 16)
 
diff --git a/tools/testing/selftests/kvm/lib/guest_modes.c b/tools/testing/selftests/kvm/lib/guest_modes.c
index 25bff307c71f..c330f414ef96 100644
--- a/tools/testing/selftests/kvm/lib/guest_modes.c
+++ b/tools/testing/selftests/kvm/lib/guest_modes.c
@@ -22,6 +22,22 @@ void guest_modes_append_default(void)
 		}
 	}
 #endif
+#ifdef __s390x__
+	{
+		int kvm_fd, vm_fd;
+		struct kvm_s390_vm_cpu_processor info;
+
+		kvm_fd = open_kvm_dev_path_or_exit();
+		vm_fd = ioctl(kvm_fd, KVM_CREATE_VM, 0);
+		kvm_device_access(vm_fd, KVM_S390_VM_CPU_MODEL,
+				  KVM_S390_VM_CPU_PROCESSOR, &info, false);
+		close(vm_fd);
+		close(kvm_fd);
+		/* Starting with z13 we have 47bits of physical address */
+		if (info.ibc >= 0x30)
+			guest_mode_append(VM_MODE_P47V64_4K, true, true);
+	}
+#endif
 }
 
 void for_each_guest_mode(void (*func)(enum vm_guest_mode, void *), void *arg)
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index a2b732cf96ea..8606000c439e 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -176,6 +176,7 @@ const char *vm_guest_mode_string(uint32_t i)
 		[VM_MODE_P40V48_64K]	= "PA-bits:40,  VA-bits:48, 64K pages",
 		[VM_MODE_PXXV48_4K]	= "PA-bits:ANY, VA-bits:48,  4K pages",
 		[VM_MODE_P47V64_4K]	= "PA-bits:47,  VA-bits:64,  4K pages",
+		[VM_MODE_P44V64_4K]	= "PA-bits:44,  VA-bits:64,  4K pages",
 	};
 	_Static_assert(sizeof(strings)/sizeof(char *) == NUM_VM_MODES,
 		       "Missing new mode strings?");
@@ -194,6 +195,7 @@ const struct vm_guest_mode_params vm_guest_mode_params[] = {
 	{ 40, 48, 0x10000, 16 },
 	{  0,  0,  0x1000, 12 },
 	{ 47, 64,  0x1000, 12 },
+	{ 44, 64,  0x1000, 12 },
 };
 _Static_assert(sizeof(vm_guest_mode_params)/sizeof(struct vm_guest_mode_params) == NUM_VM_MODES,
 	       "Missing new mode params?");
@@ -282,6 +284,9 @@ struct kvm_vm *vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
 	case VM_MODE_P47V64_4K:
 		vm->pgtable_levels = 5;
 		break;
+	case VM_MODE_P44V64_4K:
+		vm->pgtable_levels = 5;
+		break;
 	default:
 		TEST_FAIL("Unknown guest mode, mode: 0x%x", mode);
 	}
-- 
2.31.1