selftests: kvm: Check whether SIDA memop fails for normal guests

Commit 2c212e1b ("KVM: s390: Return error on SIDA memop on normal
guest") fixed the behavior of the SIDA memops for normal guests. It
would be nice to have a way to test whether the current kernel has
the fix applied or not. Thus add a check to the KVM selftests for
these two memops.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220215074824.188440-1-thuth@redhat.comSigned-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

tools/testing/selftests/kvm/s390x/memop.c

@@ -160,6 +160,21 @@ int main(int argc, char *argv[])
 	run->psw_mask &= ~(3UL << (63 - 17));   /* Disable AR mode */
 	vcpu_run(vm, VCPU_ID);                  /* Run to sync new state */
 
+	/* Check that the SIDA calls are rejected for non-protected guests */
+	ksmo.gaddr = 0;
+	ksmo.flags = 0;
+	ksmo.size = 8;
+	ksmo.op = KVM_S390_MEMOP_SIDA_READ;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.sida_offset = 0x1c0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == EINVAL,
+		    "ioctl does not reject SIDA_READ in non-protected mode");
+	ksmo.op = KVM_S390_MEMOP_SIDA_WRITE;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == EINVAL,
+		    "ioctl does not reject SIDA_WRITE in non-protected mode");
+
 	kvm_vm_free(vm);
 
 	return 0;