Merge tag 'kvm-s390-next-6.19-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

- SCA rework
- VIRT_XFER_TO_GUEST_WORK support
- Operation exception forwarding support
- Cleanups

2 files changed, 141 insertions, 0 deletions

diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm
index 1f92cc28d58b..ba5c2b643efa 100644
--- a/tools/testing/selftests/kvm/Makefile.kvm
+++ b/tools/testing/selftests/kvm/Makefile.kvm
@@ -198,6 +198,7 @@ TEST_GEN_PROGS_s390 += s390/debug_test
 TEST_GEN_PROGS_s390 += s390/cpumodel_subfuncs_test
 TEST_GEN_PROGS_s390 += s390/shared_zeropage_test
 TEST_GEN_PROGS_s390 += s390/ucontrol_test
+TEST_GEN_PROGS_s390 += s390/user_operexec
 TEST_GEN_PROGS_s390 += rseq_test
 
 TEST_GEN_PROGS_riscv = $(TEST_GEN_PROGS_COMMON)
diff --git a/tools/testing/selftests/kvm/s390/user_operexec.c b/tools/testing/selftests/kvm/s390/user_operexec.c
new file mode 100644
index 000000000000..714906c1d12a
--- /dev/null
+++ b/tools/testing/selftests/kvm/s390/user_operexec.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Test operation exception forwarding.
+ *
+ * Copyright IBM Corp. 2025
+ *
+ * Authors:
+ *  Janosch Frank <frankja@linux.ibm.com>
+ */
+#include "kselftest.h"
+#include "kvm_util.h"
+#include "test_util.h"
+#include "sie.h"
+
+#include <linux/kvm.h>
+
+static void guest_code_instr0(void)
+{
+	asm(".word 0x0000");
+}
+
+static void test_user_instr0(void)
+{
+	struct kvm_vcpu *vcpu;
+	struct kvm_vm *vm;
+	int rc;
+
+	vm = vm_create_with_one_vcpu(&vcpu, guest_code_instr0);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_INSTR0, 0);
+	TEST_ASSERT_EQ(0, rc);
+
+	vcpu_run(vcpu);
+	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_OPEREXC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0);
+
+	kvm_vm_free(vm);
+}
+
+static void guest_code_user_operexec(void)
+{
+	asm(".word 0x0807");
+}
+
+static void test_user_operexec(void)
+{
+	struct kvm_vcpu *vcpu;
+	struct kvm_vm *vm;
+	int rc;
+
+	vm = vm_create_with_one_vcpu(&vcpu, guest_code_user_operexec);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_OPEREXEC, 0);
+	TEST_ASSERT_EQ(0, rc);
+
+	vcpu_run(vcpu);
+	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_OPEREXC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0x0807);
+
+	kvm_vm_free(vm);
+
+	/*
+	 * Since user_operexec is the superset it can be used for the
+	 * 0 instruction.
+	 */
+	vm = vm_create_with_one_vcpu(&vcpu, guest_code_instr0);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_OPEREXEC, 0);
+	TEST_ASSERT_EQ(0, rc);
+
+	vcpu_run(vcpu);
+	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_OPEREXC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0);
+
+	kvm_vm_free(vm);
+}
+
+/* combine user_instr0 and user_operexec */
+static void test_user_operexec_combined(void)
+{
+	struct kvm_vcpu *vcpu;
+	struct kvm_vm *vm;
+	int rc;
+
+	vm = vm_create_with_one_vcpu(&vcpu, guest_code_user_operexec);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_INSTR0, 0);
+	TEST_ASSERT_EQ(0, rc);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_OPEREXEC, 0);
+	TEST_ASSERT_EQ(0, rc);
+
+	vcpu_run(vcpu);
+	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_OPEREXC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0x0807);
+
+	kvm_vm_free(vm);
+
+	/* Reverse enablement order */
+	vm = vm_create_with_one_vcpu(&vcpu, guest_code_user_operexec);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_OPEREXEC, 0);
+	TEST_ASSERT_EQ(0, rc);
+	rc = __vm_enable_cap(vm, KVM_CAP_S390_USER_INSTR0, 0);
+	TEST_ASSERT_EQ(0, rc);
+
+	vcpu_run(vcpu);
+	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_OPEREXC);
+	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0x0807);
+
+	kvm_vm_free(vm);
+}
+
+/*
+ * Run all tests above.
+ *
+ * Enablement after VCPU has been added is automatically tested since
+ * we enable the capability after VCPU creation.
+ */
+static struct testdef {
+	const char *name;
+	void (*test)(void);
+} testlist[] = {
+	{ "instr0", test_user_instr0 },
+	{ "operexec", test_user_operexec },
+	{ "operexec_combined", test_user_operexec_combined},
+};
+
+int main(int argc, char *argv[])
+{
+	int idx;
+
+	TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_USER_INSTR0));
+
+	ksft_print_header();
+	ksft_set_plan(ARRAY_SIZE(testlist));
+	for (idx = 0; idx < ARRAY_SIZE(testlist); idx++) {
+		testlist[idx].test();
+		ksft_test_result_pass("%s\n", testlist[idx].name);
+	}
+	ksft_finished();
+}