* [PATCH 1/6] KVM: s390: selftests: Add kvm_exit test for instruction intercepts
2026-11-10 11:16 [PATCH 0/6] KVM: s390: selftests: Add selftests for KVM exits on s390x Aaron M. Brown
@ 2026-11-10 11:16 ` Aaron M. Brown
2026-11-10 11:30 ` sashiko-bot
2026-11-10 11:16 ` [PATCH 2/6] KVM: s390: selftests: Add SIGP and program exception tests Aaron M. Brown
` (4 subsequent siblings)
5 siblings, 1 reply; 13+ messages in thread
From: Aaron M. Brown @ 2026-11-10 11:16 UTC (permalink / raw)
To: kvm
Cc: Janosch Frank, Claudio Imbrenda, Christian Borntraeger,
linux-s390, linux-kselftest, Nitya Khamar
Add a selftest for the exits KVM reports to userspace on s390x, mainly
KVM_EXIT_S390_SIEIC. This patch adds the harness and the instruction
intercept tests:
- DIAG 0x500: inject an external call, check it is pending, resume, and
compare the registers with those synced in kvm_run.
- DIAG 0x501: check the opcode and diagnose code in ipa and ipb.
- DIAG 0x501 with registers set beforehand: check they are intact.
Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
---
tools/testing/selftests/kvm/Makefile.kvm | 1 +
.../kvm/include/s390/kvm_lifecycle.h | 35 +++
tools/testing/selftests/kvm/s390/kvm_exit.c | 212 ++++++++++++++++++
3 files changed, 248 insertions(+)
create mode 100644 tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h
create mode 100644 tools/testing/selftests/kvm/s390/kvm_exit.c
diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm
index 17a4256e9081..a46a75c90e66 100644
--- a/tools/testing/selftests/kvm/Makefile.kvm
+++ b/tools/testing/selftests/kvm/Makefile.kvm
@@ -232,6 +232,7 @@ TEST_GEN_PROGS_s390 += s390/irq_routing
TEST_GEN_PROGS_s390 += mmu_stress_test
TEST_GEN_PROGS_s390 += pre_fault_memory_test
TEST_GEN_PROGS_s390 += s390/irq_injection
+TEST_GEN_PROGS_s390 += s390/kvm_exit
TEST_GEN_PROGS_riscv = $(TEST_GEN_PROGS_COMMON)
TEST_GEN_PROGS_riscv += riscv/sbi_pmu_test
diff --git a/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h b/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h
new file mode 100644
index 000000000000..7dec11a6e214
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Definition of structs for KVM lifecycle tests.
+ *
+ * Copyright IBM Corp. 2026
+ *
+ * Authors:
+ * Nitya Khamar (nkhamar@linux.ibm.com)
+ * Aaron Malik Brown (aaronmbr@linux.ibm.com)
+ */
+#ifndef SELFTEST_KVM_LIFECYCLE_H
+#define SELFTEST_KVM_LIFECYCLE_H
+
+#include "kvm_util.h"
+#include <stdbool.h>
+
+struct kvm_lifecycle_testdef {
+ const char *name;
+ bool (*test)(void);
+};
+
+struct kvm_parameters {
+ struct kvm_vm *vm;
+ struct kvm_vcpu *vcpu;
+ void *guest_code;
+ struct kvm_run *run;
+ unsigned int interrupt_type;
+ struct kvm_s390_irq *irq;
+ struct kvm_s390_irq_state *irq_state;
+ struct {
+ bool immediate_exit_condition;
+ } manual_parameters;
+};
+
+#endif /* SELFTEST_KVM_LIFECYCLE_H */
diff --git a/tools/testing/selftests/kvm/s390/kvm_exit.c b/tools/testing/selftests/kvm/s390/kvm_exit.c
new file mode 100644
index 000000000000..140358357c67
--- /dev/null
+++ b/tools/testing/selftests/kvm/s390/kvm_exit.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Test for KVM Exits to userspace on s390x
+ *
+ * Copyright IBM Corp. 2026
+ *
+ * Authors:
+ * Nitya Khamar <nkhamar@linux.ibm.com>
+ * Aaron Malik Brown <aaronmbr@linux.ibm.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include "test_util.h"
+#include "kvm_util.h"
+#include "kselftest.h"
+#include <errno.h>
+#include "processor.h"
+#include "ucall_common.h"
+#include "sie.h"
+#include "kvm_lifecycle.h"
+
+#define NUM_GPRS 16
+#define DIAG_ASSEMBLY_CODE 0x501
+#define IPA_DIAG 0x83
+
+static struct kvm_parameters create_vm_kvm_exit(struct kvm_parameters parameters)
+{
+ parameters.vm = vm_create_with_one_vcpu(¶meters.vcpu,
+ parameters.guest_code);
+ return parameters;
+}
+
+static void cleanup_kvm(struct kvm_parameters *parameters)
+{
+ kvm_vm_free(parameters->vm);
+}
+
+static void compare_regs(struct kvm_regs *regs, struct kvm_sync_regs *sregs)
+{
+ int register_number;
+
+ for (register_number = 0; register_number < NUM_GPRS; register_number++)
+ TEST_ASSERT_EQ(regs->gprs[register_number], sregs->gprs[register_number]);
+}
+
+static void guestcode_instruction_intercept(void)
+{
+ asm volatile("diag 0,0, 0x500\n" :::);
+ GUEST_DONE();
+}
+
+static bool test_instruction_intercept(void)
+{
+ struct kvm_parameters param = {
+ .guest_code = guestcode_instruction_intercept,
+ .interrupt_type = KVM_S390_INT_EXTERNAL_CALL,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+ struct kvm_s390_irq_state irq_state = {};
+ struct kvm_s390_irq irq = {};
+ struct kvm_regs regs;
+ int interrupts;
+
+ ksft_print_msg("Testing Instruction Intercept Exit\n");
+ param = create_vm_kvm_exit(param);
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ irq.type = param.interrupt_type;
+ irq.u.extcall.code = param.vcpu->id;
+ irq_state.len = sizeof(irq);
+ irq_state.buf = (unsigned long)&irq;
+ param.irq = &irq;
+ param.irq_state = &irq_state;
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_INST,
+ "Failed with Unexpected icptcode of 0x%x\n",
+ param.run->s390_sieic.icptcode);
+ interrupts = __vcpu_ioctl(param.vcpu, KVM_S390_SET_IRQ_STATE,
+ param.irq_state);
+ TEST_ASSERT(interrupts >= 0, "Cannot Inject Interrupt (%d)", errno);
+ irq_state.buf = (unsigned long)&irq;
+ irq_state.len = sizeof(irq);
+ interrupts = __vcpu_ioctl(param.vcpu, KVM_S390_GET_IRQ_STATE,
+ &irq_state);
+ TEST_ASSERT(interrupts > 0,
+ "Expected pending interrupt after injection, got %d", interrupts);
+ TEST_ASSERT_EQ(irq.type, KVM_S390_INT_EXTERNAL_CALL);
+ TEST_ASSERT_EQ(irq.u.extcall.code, param.vcpu->id);
+ vcpu_run(param.vcpu);
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_INST,
+ "Expected ICPT_INST from GUEST_DONE after inject, got 0x%x\n",
+ param.run->s390_sieic.icptcode);
+ vcpu_regs_get(param.vcpu, ®s);
+ compare_regs(®s, ¶m.run->s.regs);
+ cleanup_kvm(¶m);
+ return true;
+}
+
+static void guestcode_diagnose_hypercall(void)
+{
+ asm volatile("diag 0,0, 0x501\n" :::);
+}
+
+static bool test_diagnose_code(void)
+{
+ struct kvm_parameters param = {
+ .guest_code = guestcode_diagnose_hypercall,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+ ksft_print_msg("Testing Diagnosis Hypercall Exit\n");
+ param = create_vm_kvm_exit(param);
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_INST,
+ "Failed with Unexpected Exit Reason of %u and icptcode of 0x%x\n",
+ param.run->exit_reason, param.run->s390_sieic.icptcode);
+ TEST_ASSERT(param.run->s390_sieic.ipa >> 8 == IPA_DIAG,
+ "Failed with Unexpected Opcode of %u\n",
+ param.run->s390_sieic.ipa >> 8);
+ TEST_ASSERT(param.run->s390_sieic.ipb >> 16 == DIAG_ASSEMBLY_CODE,
+ "Failed with Unexpected Diagnose Code of %u\n",
+ param.run->s390_sieic.ipb >> 16);
+ cleanup_kvm(¶m);
+ return true;
+}
+
+static void guestcode_diagnose_conditional(void)
+{
+ asm volatile("lghi %%r3,0x3333\n"
+ "lghi %%r5, 0x555\n"
+ "lghi %%r6, 0x3333\n"
+ "cgrjne %%r6, %%r3, 1f\n"
+ "diag 0,0, 0x501\n"
+ "1:\n"
+ :
+ :
+ : "r3", "r5", "r6"
+ );
+ GUEST_DONE();
+}
+
+static bool test_diagnose_conditional_code(void)
+{
+ struct kvm_parameters param = {
+ .guest_code = guestcode_diagnose_conditional,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+ struct kvm_regs regs;
+
+ ksft_print_msg("Testing Diagnosis Hypercall for Conditional Code Exit\n");
+ param = create_vm_kvm_exit(param);
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_INST,
+ "Failed with Unexpected Exit Reason of %u and icptcode of 0x%x\n",
+ param.run->exit_reason, param.run->s390_sieic.icptcode);
+ TEST_ASSERT(param.run->s390_sieic.ipa >> 8 == IPA_DIAG,
+ "Failed with Unexpected Opcode of %u\n",
+ param.run->s390_sieic.ipa >> 8);
+ TEST_ASSERT(param.run->s390_sieic.ipb >> 16 == DIAG_ASSEMBLY_CODE,
+ "Failed with Unexpected Diagnose Code of %u\n",
+ param.run->s390_sieic.ipb >> 16);
+ vcpu_regs_get(param.vcpu, ®s);
+ TEST_ASSERT_EQ(regs.gprs[3], 0x3333);
+ TEST_ASSERT_EQ(regs.gprs[5], 0x555);
+ TEST_ASSERT_EQ(regs.gprs[6], 0x3333);
+ cleanup_kvm(¶m);
+ return true;
+}
+
+static void test(void)
+{
+ int i;
+ struct kvm_lifecycle_testdef testlist[] = {
+ {
+ .name = "Testing Instruction Intercepts",
+ .test = test_instruction_intercept,
+ },
+ {
+ .name = "Testing DIAG Code",
+ .test = test_diagnose_code,
+ },
+ {
+ .name = "Testing Conditional DIAG Code",
+ .test = test_diagnose_conditional_code,
+ },
+ };
+
+ ksft_print_header();
+ ksft_set_plan(ARRAY_SIZE(testlist));
+
+ for (i = 0; i < ARRAY_SIZE(testlist); i++) {
+ if (testlist[i].test())
+ ksft_test_result_pass("%s\n", testlist[i].name);
+ else
+ ksft_test_result_skip("%s\n", testlist[i].name);
+ }
+}
+
+int main(void)
+{
+ TEST_REQUIRE(kvm_has_cap(KVM_CAP_USER_MEMORY2));
+ TEST_REQUIRE(kvm_has_cap(KVM_CAP_SYNC_REGS));
+ test();
+ ksft_finished();
+}
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH 2/6] KVM: s390: selftests: Add SIGP and program exception tests
2026-11-10 11:16 [PATCH 0/6] KVM: s390: selftests: Add selftests for KVM exits on s390x Aaron M. Brown
2026-11-10 11:16 ` [PATCH 1/6] KVM: s390: selftests: Add kvm_exit test for instruction intercepts Aaron M. Brown
@ 2026-11-10 11:16 ` Aaron M. Brown
2026-11-10 11:24 ` sashiko-bot
2026-11-10 11:16 ` [PATCH 3/6] KVM: s390: selftests: Add wait state and VM lifecycle tests Aaron M. Brown
` (3 subsequent siblings)
5 siblings, 1 reply; 13+ messages in thread
From: Aaron M. Brown @ 2026-11-10 11:16 UTC (permalink / raw)
To: kvm
Cc: Janosch Frank, Claudio Imbrenda, Christian Borntraeger,
linux-s390, linux-kselftest, Nitya Khamar
Add tests for:
- SIGP: a second vCPU stops vCPU 0. Both vCPUs are set to operating
first, as KVM ignores a stop order sent to a stopped vCPU. Check for
ICPT_STOP.
- Addressing exception (DAT off): check for program code 0x05.
- Segment translation exception (DAT on): check for program code 0x10.
The program new PSW is set to a disabled wait so the guest exits
deterministically.
Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
---
tools/testing/selftests/kvm/s390/kvm_exit.c | 146 ++++++++++++++++++++
1 file changed, 146 insertions(+)
diff --git a/tools/testing/selftests/kvm/s390/kvm_exit.c b/tools/testing/selftests/kvm/s390/kvm_exit.c
index 140358357c67..4a6f01ff14ca 100644
--- a/tools/testing/selftests/kvm/s390/kvm_exit.c
+++ b/tools/testing/selftests/kvm/s390/kvm_exit.c
@@ -25,6 +25,12 @@
#define NUM_GPRS 16
#define DIAG_ASSEMBLY_CODE 0x501
#define IPA_DIAG 0x83
+#define PSW_MASK_64BIT_DAT_OFF 0x0000000180000000ULL
+#define PGM_CODE_SEGMENT_TRANSLATION 0x10
+#define PGM_CODE_GPA_ADDRESS 0x8e
+#define PGM_CODE_MASK 0x7f
+#define PGM_NEW_PSW_GPA 0x1d0
+#define PSW_DISABLED_WAIT 0x0002000180000000ULL
static struct kvm_parameters create_vm_kvm_exit(struct kvm_parameters parameters)
{
@@ -174,6 +180,134 @@ static bool test_diagnose_conditional_code(void)
return true;
}
+/*
+ * Make a program interrupt end in a disabled wait, which KVM reports to
+ * userspace as ICPT_WAIT. This does not depend on how KVM handles
+ * repeated operation exceptions.
+ */
+static void set_pgm_new_psw_disabled_wait(struct kvm_vm *vm)
+{
+ uint64_t *new_psw = addr_gpa2hva(vm, PGM_NEW_PSW_GPA);
+
+ new_psw[0] = PSW_DISABLED_WAIT;
+ new_psw[1] = 0;
+}
+
+static void guestcode_sigp(void)
+{
+ asm volatile(
+ "lghi %%r3, 0\n"
+ "sigp %%r1, %%r3, 0x05\n"
+ :
+ :
+ : "r1", "r3"
+ );
+ GUEST_DONE();
+}
+
+static bool test_sigp_signals(void)
+{
+ struct kvm_parameters param = {
+ .guest_code = guestcode_sigp,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+ struct kvm_mp_state mp_state = { .mp_state = KVM_MP_STATE_OPERATING };
+ struct kvm_vcpu *vcpu1;
+ struct kvm_regs regs;
+
+ ksft_print_msg("Testing SIGP KVM Exit\n");
+ param = create_vm_kvm_exit(param);
+ vcpu1 = vm_vcpu_add(param.vm, 1, guestcode_sigp);
+ /* New vCPUs are stopped, and KVM ignores a SIGP STOP sent to one */
+ vcpu_mp_state_set(param.vcpu, &mp_state);
+ vcpu_mp_state_set(vcpu1, &mp_state);
+ vcpu_regs_get(param.vcpu, ®s);
+ regs.gprs[3] = 0x3333;
+ vcpu_regs_set(param.vcpu, ®s);
+ vcpu_run(vcpu1);
+ /* vcpu1 exits after GUEST_DONE() ucall */
+ TEST_ASSERT_KVM_EXIT_REASON(vcpu1, KVM_EXIT_S390_SIEIC);
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT_EQ(param.run->s390_sieic.icptcode, ICPT_STOP);
+ /*
+ * The pending SIGP STOP stops vcpu0 before it runs any guest code
+ * (the guest would clear r3), so r3 keeps the marker value.
+ */
+ TEST_ASSERT_EQ(param.run->s.regs.gprs[3], 0x3333);
+ cleanup_kvm(¶m);
+ return true;
+}
+
+static void guestcode_address_exception(void)
+{
+ asm volatile(
+ "lghi %%r1, 0x1\n"
+ "sllg %%r1, %%r1, 0x28\n"
+ "lg %%r2, 0(%%r1)\n"
+ :
+ :
+ : "r1", "r2"
+ );
+}
+
+static bool test_address_exceptions(void)
+{
+ struct kvm_parameters param = {};
+ uint16_t pgm_code;
+
+ ksft_print_msg("Testing Address Exception Exit\n");
+ param.guest_code = guestcode_address_exception;
+ param = create_vm_kvm_exit(param);
+ set_pgm_new_psw_disabled_wait(param.vm);
+ param.vcpu->run->psw_mask &= PSW_MASK_64BIT_DAT_OFF;
+ /* The guest runs with DAT off, so the entry point must be a GPA */
+ param.vcpu->run->psw_addr = addr_gva2gpa(param.vm, param.vcpu->run->psw_addr);
+ param.vcpu->run->kvm_dirty_regs |= KVM_SYNC_ARCH0;
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT_EQ(param.run->s390_sieic.icptcode, ICPT_WAIT);
+ pgm_code = *(uint16_t *)addr_gpa2hva(param.vm, PGM_CODE_GPA_ADDRESS);
+ TEST_ASSERT((pgm_code & PGM_CODE_MASK) == 0x05,
+ "Expected PGM code 0x05 (addressing), got 0x%x\n", pgm_code);
+ cleanup_kvm(¶m);
+ return true;
+}
+
+static void guestcode_translation_exception(void)
+{
+ asm volatile(
+ "lghi %%r1, 0x1\n"
+ "sllg %%r1, %%r1, 0x14\n"
+ "lg %%r2, 0(%%r1)\n"
+ :
+ :
+ : "r1", "r2"
+ );
+}
+
+static bool test_translation_exceptions(void)
+{
+ struct kvm_parameters param = {};
+ uint16_t pgm_code;
+
+ ksft_print_msg("Testing Translation Exception KVM Exit\n");
+ param.guest_code = guestcode_translation_exception;
+ param = create_vm_kvm_exit(param);
+ set_pgm_new_psw_disabled_wait(param.vm);
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ TEST_ASSERT_KVM_EXIT_REASON(param.vcpu, KVM_EXIT_S390_SIEIC);
+ TEST_ASSERT_EQ(param.run->s390_sieic.icptcode, ICPT_WAIT);
+ pgm_code = *(uint16_t *)addr_gpa2hva(param.vm, PGM_CODE_GPA_ADDRESS);
+ TEST_ASSERT((pgm_code & PGM_CODE_MASK) == PGM_CODE_SEGMENT_TRANSLATION,
+ "Expected PGM code 0x10 (segment translation), got 0x%x\n", pgm_code);
+ cleanup_kvm(¶m);
+ return true;
+}
+
static void test(void)
{
int i;
@@ -190,6 +324,18 @@ static void test(void)
.name = "Testing Conditional DIAG Code",
.test = test_diagnose_conditional_code,
},
+ {
+ .name = "Testing SIGP Exits",
+ .test = test_sigp_signals,
+ },
+ {
+ .name = "Testing Address Exceptions",
+ .test = test_address_exceptions,
+ },
+ {
+ .name = "Testing Translation Exceptions",
+ .test = test_translation_exceptions,
+ },
};
ksft_print_header();
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH 3/6] KVM: s390: selftests: Add wait state and VM lifecycle tests
2026-11-10 11:16 [PATCH 0/6] KVM: s390: selftests: Add selftests for KVM exits on s390x Aaron M. Brown
2026-11-10 11:16 ` [PATCH 1/6] KVM: s390: selftests: Add kvm_exit test for instruction intercepts Aaron M. Brown
2026-11-10 11:16 ` [PATCH 2/6] KVM: s390: selftests: Add SIGP and program exception tests Aaron M. Brown
@ 2026-11-10 11:16 ` Aaron M. Brown
2026-11-10 11:21 ` sashiko-bot
2026-11-10 11:16 ` [PATCH 4/6] KVM: s390: selftests: Add ucontrol helpers and instruction tests Aaron M. Brown
` (2 subsequent siblings)
5 siblings, 1 reply; 13+ messages in thread
From: Aaron M. Brown @ 2026-11-10 11:16 UTC (permalink / raw)
To: kvm
Cc: Janosch Frank, Claudio Imbrenda, Christian Borntraeger,
linux-s390, linux-kselftest, Nitya Khamar
Add two tests:
- Wait state: the guest loads a PSW with the wait bit (bit 14) set and
the I/O, external and machine-check masks (bits 6, 7, 13) clear.
Check for ICPT_WAIT and the wait bit in the PSW.
- VM create and destroy: before the first KVM_RUN, check that
exit_reason is KVM_EXIT_UNKNOWN and immediate_exit is clear.
Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
---
tools/testing/selftests/kvm/s390/kvm_exit.c | 78 +++++++++++++++++++++
1 file changed, 78 insertions(+)
diff --git a/tools/testing/selftests/kvm/s390/kvm_exit.c b/tools/testing/selftests/kvm/s390/kvm_exit.c
index 4a6f01ff14ca..2f73eae1954a 100644
--- a/tools/testing/selftests/kvm/s390/kvm_exit.c
+++ b/tools/testing/selftests/kvm/s390/kvm_exit.c
@@ -27,6 +27,7 @@
#define IPA_DIAG 0x83
#define PSW_MASK_64BIT_DAT_OFF 0x0000000180000000ULL
#define PGM_CODE_SEGMENT_TRANSLATION 0x10
+#define PSW_WAIT_BIT_MASK (1ULL << (63 - 14))
#define PGM_CODE_GPA_ADDRESS 0x8e
#define PGM_CODE_MASK 0x7f
#define PGM_NEW_PSW_GPA 0x1d0
@@ -308,6 +309,75 @@ static bool test_translation_exceptions(void)
return true;
}
+static uint64_t psw_save[2] __aligned(16);
+
+static void guestcode_wait_state(void)
+{
+ register uint64_t *psw_ptr asm("r4") = psw_save;
+
+ asm volatile(
+ "lghi %%r3, 0x3333\n"
+ "lgrl %%r7, 1f\n"
+ "stg %%r7, 0(%%r4)\n"
+ "xgr %%r5, %%r5\n"
+ "stg %%r5, 8(%%r4)\n"
+ "lpswe 0(%%r4)\n"
+ ".align 8\n"
+ "1: .quad 0x0002000180000000\n"
+ :
+ : "d"(psw_ptr)
+ : "r3", "r5", "r7", "memory"
+ );
+}
+
+static bool test_wait_state(void)
+{
+ struct kvm_parameters param = {};
+ struct kvm_regs regs;
+
+ ksft_print_msg("Testing Wait State Exit\n");
+ param.guest_code = guestcode_wait_state;
+ param = create_vm_kvm_exit(param);
+ vcpu_run(param.vcpu);
+ param.run = param.vcpu->run;
+ TEST_ASSERT(param.run->exit_reason == KVM_EXIT_S390_SIEIC,
+ "Expected KVM_EXIT_S390_SIEIC, got %u\n",
+ param.run->exit_reason);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_WAIT,
+ "Failed with Unexpected Exit Reason of %u and icptcode of 0x%x\n",
+ param.run->exit_reason, param.run->s390_sieic.icptcode);
+ vcpu_regs_get(param.vcpu, ®s);
+ TEST_ASSERT(regs.gprs[3] == 0x3333,
+ "Expected 0x3333 but got 0x%llx\n", regs.gprs[3]);
+ /* Check PSW wait bit (bit 14 from MSB = bit 63-14 from LSB) */
+ TEST_ASSERT((param.run->psw_mask & PSW_WAIT_BIT_MASK) != 0,
+ "PSW wait bit not set, PSW Mask = 0x%llx\n",
+ param.run->psw_mask);
+ cleanup_kvm(¶m);
+ return true;
+}
+
+static void guestcode_nop(void)
+{
+ GUEST_DONE();
+}
+
+static bool test_vm_create_and_destroy(void)
+{
+ struct kvm_parameters parameters = {.guest_code = guestcode_nop};
+
+ ksft_print_msg("Testing VM Closure without Running vCPU\n");
+ parameters = create_vm_kvm_exit(parameters);
+ TEST_ASSERT(parameters.vcpu->run->exit_reason == KVM_EXIT_UNKNOWN,
+ "Unexpected Exit Reason Before vCPU Execution: %u\n",
+ parameters.vcpu->run->exit_reason);
+ TEST_ASSERT(parameters.vcpu->run->immediate_exit == 0,
+ "Immediate Exit Unexpected Behavior: %d\n",
+ parameters.vcpu->run->immediate_exit);
+ cleanup_kvm(¶meters);
+ return true;
+}
+
static void test(void)
{
int i;
@@ -336,6 +406,14 @@ static void test(void)
.name = "Testing Translation Exceptions",
.test = test_translation_exceptions,
},
+ {
+ .name = "Testing Wait State",
+ .test = test_wait_state,
+ },
+ {
+ .name = "Testing VM Create and Destroy",
+ .test = test_vm_create_and_destroy,
+ },
};
ksft_print_header();
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH 4/6] KVM: s390: selftests: Add ucontrol helpers and instruction tests
2026-11-10 11:16 [PATCH 0/6] KVM: s390: selftests: Add selftests for KVM exits on s390x Aaron M. Brown
` (2 preceding siblings ...)
2026-11-10 11:16 ` [PATCH 3/6] KVM: s390: selftests: Add wait state and VM lifecycle tests Aaron M. Brown
@ 2026-11-10 11:16 ` Aaron M. Brown
2026-11-10 11:24 ` sashiko-bot
2026-11-10 11:16 ` [PATCH 5/6] KVM: s390: selftests: Add ucontrol storage key and immediate exit tests Aaron M. Brown
2026-11-10 11:16 ` [PATCH 6/6] KVM: s390: selftests: Add clock comparator interrupt test Aaron M. Brown
5 siblings, 1 reply; 13+ messages in thread
From: Aaron M. Brown @ 2026-11-10 11:16 UTC (permalink / raw)
To: kvm
Cc: Janosch Frank, Claudio Imbrenda, Christian Borntraeger,
linux-s390, linux-kselftest, Nitya Khamar
Add helpers to run a guest on a ucontrol VM and use them to test
instruction intercepts handled in userspace.
manual_kvm_creation_execution() creates the VM and vCPU, maps 4 MiB
with KVM_S390_UCAS_MAP, sets the PSW and r15, and runs the vCPU. r15
must be valid because C guest functions adjust it in their prologue.
ucontrol_available() checks KVM_CAP_S390_UCONTROL and CAP_SYS_ADMIN.
Tests that need it are skipped, with a reason from the new skip_reason
field.
Tests added: STSI, TSCH and STSCH. Each must cause ICPT_INST with the
expected opcode.
Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
---
.../kvm/include/s390/kvm_lifecycle.h | 8 +
tools/testing/selftests/kvm/s390/kvm_exit.c | 220 +++++++++++++++++-
2 files changed, 227 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h b/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h
index 7dec11a6e214..8b17eff9cb3e 100644
--- a/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h
+++ b/tools/testing/selftests/kvm/include/s390/kvm_lifecycle.h
@@ -17,6 +17,7 @@
struct kvm_lifecycle_testdef {
const char *name;
bool (*test)(void);
+ const char *skip_reason;
};
struct kvm_parameters {
@@ -28,7 +29,14 @@ struct kvm_parameters {
struct kvm_s390_irq *irq;
struct kvm_s390_irq_state *irq_state;
struct {
+ struct kvm_s390_sie_block *sie_block;
+ struct kvm_s390_ucas_mapping map;
bool immediate_exit_condition;
+ void *vm_mem;
+ int run_size;
+ int vcpu_fd;
+ int kvm_fd;
+ int vm_fd;
} manual_parameters;
};
diff --git a/tools/testing/selftests/kvm/s390/kvm_exit.c b/tools/testing/selftests/kvm/s390/kvm_exit.c
index 2f73eae1954a..d0a3894daf0d 100644
--- a/tools/testing/selftests/kvm/s390/kvm_exit.c
+++ b/tools/testing/selftests/kvm/s390/kvm_exit.c
@@ -13,6 +13,7 @@
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
+#include <linux/capability.h>
#include "test_util.h"
#include "kvm_util.h"
#include "kselftest.h"
@@ -21,12 +22,21 @@
#include "ucall_common.h"
#include "sie.h"
#include "kvm_lifecycle.h"
+#include <linux/sizes.h>
+
+/* capget() is used to check CAP_SYS_ADMIN without a libcap dependency */
+int capget(cap_user_header_t header, cap_user_data_t data);
#define NUM_GPRS 16
#define DIAG_ASSEMBLY_CODE 0x501
#define IPA_DIAG 0x83
#define PSW_MASK_64BIT_DAT_OFF 0x0000000180000000ULL
#define PGM_CODE_SEGMENT_TRANSLATION 0x10
+#define CODE_GPA (3 * SZ_1M)
+#define MEM_SIZE (4 * SZ_1M)
+#define STSI_IPA 0xb27d
+#define TSCH_IPA 0xb235
+#define STSCH_IPA 0xb234
#define PSW_WAIT_BIT_MASK (1ULL << (63 - 14))
#define PGM_CODE_GPA_ADDRESS 0x8e
#define PGM_CODE_MASK 0x7f
@@ -53,6 +63,96 @@ static void compare_regs(struct kvm_regs *regs, struct kvm_sync_regs *sregs)
TEST_ASSERT_EQ(regs->gprs[register_number], sregs->gprs[register_number]);
}
+static struct kvm_parameters manual_kvm_creation_execution(struct kvm_parameters param)
+{
+ int rc;
+
+ param.manual_parameters.kvm_fd = open_kvm_dev_path_or_exit();
+ param.manual_parameters.vm_fd = ioctl(param.manual_parameters.kvm_fd,
+ KVM_CREATE_VM, KVM_VM_S390_UCONTROL);
+
+ TEST_ASSERT(param.manual_parameters.vm_fd >= 0, "KVM_CREATE_VM failed (%d)", errno);
+ param.manual_parameters.vcpu_fd = ioctl(param.manual_parameters.vm_fd, KVM_CREATE_VCPU, 0);
+ TEST_ASSERT(param.manual_parameters.vcpu_fd >= 0, "KVM_CREATE_VCPU failed (%d)", errno);
+
+ param.manual_parameters.vm_mem = aligned_alloc(SZ_1M, MEM_SIZE);
+ TEST_ASSERT(param.manual_parameters.vm_mem, "aligned_alloc failed (%d)", errno);
+
+ param.manual_parameters.map.user_addr = (uintptr_t)param.manual_parameters.vm_mem;
+ param.manual_parameters.map.vcpu_addr = 0;
+ param.manual_parameters.map.length = MEM_SIZE;
+ rc = ioctl(param.manual_parameters.vcpu_fd, KVM_S390_UCAS_MAP,
+ ¶m.manual_parameters.map);
+ TEST_ASSERT(rc == 0, "KVM_S390_UCAS_MAP failed (%d)", errno);
+
+ rc = ioctl(param.manual_parameters.vcpu_fd, KVM_S390_VCPU_FAULT, (void *)0);
+ TEST_ASSERT(rc == 0, "KVM_S390_VCPU_FAULT failed (%d)", errno);
+
+ /* Copy guest code to physical GPA */
+ memcpy((void *)((uintptr_t)param.manual_parameters.vm_mem + CODE_GPA),
+ param.guest_code, PAGE_SIZE);
+
+ /* Map kvm_run */
+ param.manual_parameters.run_size = ioctl(param.manual_parameters.kvm_fd,
+ KVM_GET_VCPU_MMAP_SIZE, NULL);
+ TEST_ASSERT(param.manual_parameters.run_size >= (int)sizeof(struct kvm_run),
+ "KVM_GET_VCPU_MMAP_SIZE returned (%d) expected >= %zu",
+ param.manual_parameters.run_size, sizeof(struct kvm_run));
+ param.run = mmap(NULL, param.manual_parameters.run_size,
+ PROT_READ | PROT_WRITE, MAP_SHARED,
+ param.manual_parameters.vcpu_fd, 0);
+ TEST_ASSERT(param.run != MAP_FAILED, "mmap kvm_run failed (%d)", errno);
+
+ /* Map SIE block and clear STOPPED flag - required for ucontrol VMs */
+ param.manual_parameters.sie_block = mmap(NULL, PAGE_SIZE,
+ PROT_READ | PROT_WRITE, MAP_SHARED,
+ param.manual_parameters.vcpu_fd,
+ KVM_S390_SIE_PAGE_OFFSET << PAGE_SHIFT);
+ TEST_ASSERT(param.manual_parameters.sie_block != MAP_FAILED,
+ "mmap sie_block failed (%d)", errno);
+ param.manual_parameters.sie_block->cpuflags &= ~CPUSTAT_STOPPED;
+
+ /* DAT off + 64-bit mode; PSW address = physical code GPA */
+ param.run->psw_mask = PSW_MASK_64BIT_DAT_OFF;
+ param.run->psw_addr = CODE_GPA;
+ param.run->kvm_dirty_regs |= KVM_SYNC_ARCH0;
+
+ /* Point r15 at a valid guest stack below the code page */
+ param.run->s.regs.gprs[15] = CODE_GPA - 160;
+ param.run->kvm_dirty_regs |= KVM_SYNC_GPRS;
+
+ rc = ioctl(param.manual_parameters.vcpu_fd, KVM_RUN, NULL);
+ TEST_ASSERT(rc == 0, "KVM_RUN failed (%d)", errno);
+
+ return param;
+}
+
+static void manual_cleanup(struct kvm_parameters param)
+{
+ munmap(param.manual_parameters.sie_block, PAGE_SIZE);
+ munmap(param.run, param.manual_parameters.run_size);
+ close(param.manual_parameters.vcpu_fd);
+ close(param.manual_parameters.vm_fd);
+ close(param.manual_parameters.kvm_fd);
+ free(param.manual_parameters.vm_mem);
+}
+
+static bool ucontrol_available(void)
+{
+ struct __user_cap_data_struct data[_LINUX_CAPABILITY_U32S_3];
+ struct __user_cap_header_struct hdr = {
+ .version = _LINUX_CAPABILITY_VERSION_3,
+ };
+ int rc;
+
+ rc = capget(&hdr, data);
+ if (rc < 0)
+ return false;
+ if (!(data->effective & CAP_TO_MASK(CAP_SYS_ADMIN)))
+ return false;
+ return kvm_has_cap(KVM_CAP_S390_UCONTROL);
+}
+
static void guestcode_instruction_intercept(void)
{
asm volatile("diag 0,0, 0x500\n" :::);
@@ -378,6 +478,113 @@ static bool test_vm_create_and_destroy(void)
return true;
}
+/* Tests below require KVM_CAP_S390_UCONTROL and are skipped if absent. */
+
+static void guestcode_system_information_calls(void)
+{
+ static uint8_t stsi_buf[4096] __aligned(4096);
+
+ register uint8_t *ptr asm("r1") = stsi_buf;
+
+ asm volatile(
+ "lghi %%r0, 0x0302\n"
+ "stsi 0(%%r1)\n"
+ :
+ : "d"(ptr)
+ : "r0", "memory"
+ );
+ GUEST_DONE();
+}
+
+static bool test_system_information_calls(void)
+{
+ struct kvm_parameters parameters = {
+ .guest_code = guestcode_system_information_calls,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+
+ if (!ucontrol_available())
+ return false;
+
+ ksft_print_msg("Testing System Information Call Exits\n");
+
+ parameters = manual_kvm_creation_execution(parameters);
+
+ TEST_ASSERT(parameters.run->exit_reason == KVM_EXIT_S390_SIEIC,
+ "Expected KVM_EXIT_S390_SIEIC, got %u\n", parameters.run->exit_reason);
+ TEST_ASSERT(parameters.run->s390_sieic.icptcode == ICPT_INST,
+ "Failed with icptcode of 0x%x\n", parameters.run->s390_sieic.icptcode);
+ TEST_ASSERT(parameters.run->s390_sieic.ipa == STSI_IPA,
+ "Expected STSI opcode 0xb27d, got 0x%x\n", parameters.run->s390_sieic.ipa);
+ manual_cleanup(parameters);
+ return true;
+}
+
+static void guestcode_tsch(void)
+{
+ register uint64_t buf asm("r2") = 0x3000;
+
+ asm volatile(
+ "lgfi %%r1, 0x00010000\n"
+ "tsch 0(%%r2)\n"
+ :
+ : "d"(buf)
+ : "r1"
+ );
+}
+
+static void guestcode_stsch(void)
+{
+ register uint64_t buffer asm("r2") = 0x3000;
+
+ asm volatile(
+ "lgfi %%r1, 0x00010000\n"
+ "stsch 0(%%r2)\n"
+ :
+ : "d"(buffer)
+ : "r1"
+ );
+}
+
+static const struct {
+ void (*guest_code)(void);
+ uint16_t expected_ipa;
+} io_tests[] = {
+ {guestcode_tsch, TSCH_IPA},
+ {guestcode_stsch, STSCH_IPA},
+};
+
+static bool test_io_instruction_code(void)
+{
+ int i;
+
+ if (!ucontrol_available())
+ return false;
+
+ ksft_print_msg("Testing IO Instruction Exit for TSCH and STSCH\n");
+ for (i = 0; i < ARRAY_SIZE(io_tests); i++) {
+ struct kvm_parameters parameter = {
+ .guest_code = io_tests[i].guest_code,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+
+ parameter = manual_kvm_creation_execution(parameter);
+
+ TEST_ASSERT(parameter.run->exit_reason == KVM_EXIT_S390_SIEIC,
+ "Expected KVM_EXIT_S390_SIEIC, got %u\n",
+ parameter.run->exit_reason);
+ TEST_ASSERT(parameter.run->s390_sieic.icptcode == ICPT_INST,
+ "Failed with icptcode of 0x%x\n",
+ parameter.run->s390_sieic.icptcode);
+ TEST_ASSERT(parameter.run->s390_sieic.ipa == io_tests[i].expected_ipa,
+ "Expected opcode 0x%x, got 0x%x\n",
+ io_tests[i].expected_ipa,
+ parameter.run->s390_sieic.ipa);
+ manual_cleanup(parameter);
+ }
+ return true;
+}
+
static void test(void)
{
int i;
@@ -414,6 +621,16 @@ static void test(void)
.name = "Testing VM Create and Destroy",
.test = test_vm_create_and_destroy,
},
+ {
+ .name = "Testing System Information Calls",
+ .test = test_system_information_calls,
+ .skip_reason = "KVM_CAP_S390_UCONTROL unavailable or insufficient privilege"
+ },
+ {
+ .name = "Testing IO Instruction Exits",
+ .test = test_io_instruction_code,
+ .skip_reason = "KVM_CAP_S390_UCONTROL unavailable or insufficient privilege"
+ },
};
ksft_print_header();
@@ -423,7 +640,8 @@ static void test(void)
if (testlist[i].test())
ksft_test_result_pass("%s\n", testlist[i].name);
else
- ksft_test_result_skip("%s\n", testlist[i].name);
+ ksft_test_result_skip("%s (%s)\n", testlist[i].name,
+ testlist[i].skip_reason ?: "unsupported");
}
}
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH 4/6] KVM: s390: selftests: Add ucontrol helpers and instruction tests
2026-11-10 11:16 ` [PATCH 4/6] KVM: s390: selftests: Add ucontrol helpers and instruction tests Aaron M. Brown
@ 2026-11-10 11:24 ` sashiko-bot
0 siblings, 0 replies; 13+ messages in thread
From: sashiko-bot @ 2026-11-10 11:24 UTC (permalink / raw)
To: Aaron M. Brown
Cc: linux-s390, Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger
> Add helpers to run a guest on a ucontrol VM and use them to test
> instruction intercepts handled in userspace.
>
> manual_kvm_creation_execution() creates the VM and vCPU, maps 4 MiB
> with KVM_S390_UCAS_MAP, sets the PSW and r15, and runs the vCPU. r15
> must be valid because C guest functions adjust it in their prologue.
>
> ucontrol_available() checks KVM_CAP_S390_UCONTROL and CAP_SYS_ADMIN.
> Tests that need it are skipped, with a reason from the new skip_reason
> field.
>
> Tests added: STSI, TSCH and STSCH. Each must cause ICPT_INST with the
> expected opcode.
>
> Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
> Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
> Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
Sashiko has reviewed this patch and found no issues.
--
Sashiko AI review · https://sashiko.dev/#/patchset/20261110111619.61760-1-aaronmbr@linux.ibm.com?part=4
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH 5/6] KVM: s390: selftests: Add ucontrol storage key and immediate exit tests
2026-11-10 11:16 [PATCH 0/6] KVM: s390: selftests: Add selftests for KVM exits on s390x Aaron M. Brown
` (3 preceding siblings ...)
2026-11-10 11:16 ` [PATCH 4/6] KVM: s390: selftests: Add ucontrol helpers and instruction tests Aaron M. Brown
@ 2026-11-10 11:16 ` Aaron M. Brown
2026-11-10 11:25 ` sashiko-bot
2026-11-10 11:16 ` [PATCH 6/6] KVM: s390: selftests: Add clock comparator interrupt test Aaron M. Brown
5 siblings, 1 reply; 13+ messages in thread
From: Aaron M. Brown @ 2026-11-10 11:16 UTC (permalink / raw)
To: kvm
Cc: Janosch Frank, Claudio Imbrenda, Christian Borntraeger,
linux-s390, linux-kselftest, Nitya Khamar
Add two more ucontrol tests:
- Storage key: the guest executes SSKE. Check for ICPT_KSS and the key
in the guest register. Skip if CPUSTAT_KSS is not set, as the
intercept is not generated then.
- Immediate exit: set immediate_exit and a marker register before
KVM_RUN. Check for EINTR, exit_reason KVM_EXIT_UNKNOWN, and that the
marker is unchanged.
Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
---
tools/testing/selftests/kvm/s390/kvm_exit.c | 107 ++++++++++++++++++++
1 file changed, 107 insertions(+)
diff --git a/tools/testing/selftests/kvm/s390/kvm_exit.c b/tools/testing/selftests/kvm/s390/kvm_exit.c
index d0a3894daf0d..4b9b30cd4e2a 100644
--- a/tools/testing/selftests/kvm/s390/kvm_exit.c
+++ b/tools/testing/selftests/kvm/s390/kvm_exit.c
@@ -37,6 +37,10 @@ int capget(cap_user_header_t header, cap_user_data_t data);
#define STSI_IPA 0xb27d
#define TSCH_IPA 0xb235
#define STSCH_IPA 0xb234
+#define EXPECTED_STORAGE_KEY 0x20
+#define IPA_SUBOPCODE_MASK_SKEY 0xff
+#define SSKE_SUBOPCODE 0x2b
+#define SSKE_OPCODE 0xb2
#define PSW_WAIT_BIT_MASK (1ULL << (63 - 14))
#define PGM_CODE_GPA_ADDRESS 0x8e
#define PGM_CODE_MASK 0x7f
@@ -121,6 +125,15 @@ static struct kvm_parameters manual_kvm_creation_execution(struct kvm_parameters
param.run->s.regs.gprs[15] = CODE_GPA - 160;
param.run->kvm_dirty_regs |= KVM_SYNC_GPRS;
+ if (param.manual_parameters.immediate_exit_condition) {
+ param.run->immediate_exit = 1;
+ param.run->s.regs.gprs[3] = 0xdead;
+ param.run->kvm_dirty_regs |= KVM_SYNC_GPRS;
+ rc = ioctl(param.manual_parameters.vcpu_fd, KVM_RUN, NULL);
+ TEST_ASSERT(rc == -1 && errno == EINTR, "KVM_RUN failed (%d)", errno);
+ return param;
+ }
+
rc = ioctl(param.manual_parameters.vcpu_fd, KVM_RUN, NULL);
TEST_ASSERT(rc == 0, "KVM_RUN failed (%d)", errno);
@@ -585,6 +598,90 @@ static bool test_io_instruction_code(void)
return true;
}
+static void guestcode_storage_key(void)
+{
+ asm volatile(
+ "lghi %%r3, 0\n"
+ "lghi %%r2, %[skey]\n"
+ "sske %%r2, %%r3\n"
+ :
+ : [skey] "i" (EXPECTED_STORAGE_KEY)
+ : "r3", "r2"
+ );
+}
+
+static bool test_storage_key_interrupt(void)
+{
+ struct kvm_parameters parameters = {
+ .guest_code = guestcode_storage_key,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+
+ if (!ucontrol_available())
+ return false;
+
+ ksft_print_msg("Testing Storage Key Interrupt KVM Exit\n");
+ parameters = manual_kvm_creation_execution(parameters);
+
+ /* Skip on hosts where sclp.has_kss is false. */
+ if (!(parameters.manual_parameters.sie_block->cpuflags & CPUSTAT_KSS)) {
+ manual_cleanup(parameters);
+ return false;
+ }
+
+ TEST_ASSERT(parameters.run->exit_reason == KVM_EXIT_S390_SIEIC,
+ "Expected KVM_EXIT_S390_SIEIC, got %u\n", parameters.run->exit_reason);
+ TEST_ASSERT(parameters.run->s390_sieic.icptcode == ICPT_KSS,
+ "Failed with Unexpected Exit Reason of %u and icptcode of 0x%x\n",
+ parameters.run->exit_reason, parameters.run->s390_sieic.icptcode);
+ TEST_ASSERT((parameters.run->s390_sieic.ipa & IPA_SUBOPCODE_MASK_SKEY) == SSKE_SUBOPCODE,
+ "Expected SSKE Sub Opcode of 0x2B, Result of 0x%x\n",
+ parameters.run->s390_sieic.ipa & IPA_SUBOPCODE_MASK_SKEY);
+ TEST_ASSERT((parameters.run->s390_sieic.ipa >> 8) == SSKE_OPCODE,
+ "Expected SSKE Opcode of 0xb2, Actual of 0x%x\n",
+ parameters.run->s390_sieic.ipa >> 8);
+ TEST_ASSERT(parameters.run->s.regs.gprs[2] == EXPECTED_STORAGE_KEY,
+ "Storage Key not stored correctly, got 0x%llx\n",
+ parameters.run->s.regs.gprs[2]);
+
+ manual_cleanup(parameters);
+ return true;
+}
+
+static void guestcode_immediate_exit(void)
+{
+ asm volatile(
+ "lghi %%r3, 0x3333\n"
+ :
+ :
+ : "r3"
+ );
+}
+
+static bool test_immediate_exit(void)
+{
+ struct kvm_parameters parameters = {
+ .guest_code = guestcode_immediate_exit,
+ .manual_parameters.immediate_exit_condition = true,
+ };
+
+ if (!ucontrol_available())
+ return false;
+
+ ksft_print_msg("Testing KVM Immediate Exit\n");
+ parameters = manual_kvm_creation_execution(parameters);
+
+ TEST_ASSERT(parameters.run->exit_reason == KVM_EXIT_UNKNOWN,
+ "Expected KVM_EXIT_UNKNOWN (0), got %u\n",
+ parameters.run->exit_reason);
+ TEST_ASSERT(parameters.run->s.regs.gprs[3] == 0xdead,
+ "Guest code executed when it should not have: r3=0x%llx\n",
+ parameters.run->s.regs.gprs[3]);
+
+ manual_cleanup(parameters);
+ return true;
+}
+
static void test(void)
{
int i;
@@ -631,6 +728,16 @@ static void test(void)
.test = test_io_instruction_code,
.skip_reason = "KVM_CAP_S390_UCONTROL unavailable or insufficient privilege"
},
+ {
+ .name = "Testing Storage Key Interrupts",
+ .test = test_storage_key_interrupt,
+ .skip_reason = "KVM_CAP_S390_UCONTROL, privilege or KSS unavailable"
+ },
+ {
+ .name = "Testing Immediate Exit",
+ .test = test_immediate_exit,
+ .skip_reason = "KVM_CAP_S390_UCONTROL unavailable or insufficient privilege"
+ },
};
ksft_print_header();
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH 6/6] KVM: s390: selftests: Add clock comparator interrupt test
2026-11-10 11:16 [PATCH 0/6] KVM: s390: selftests: Add selftests for KVM exits on s390x Aaron M. Brown
` (4 preceding siblings ...)
2026-11-10 11:16 ` [PATCH 5/6] KVM: s390: selftests: Add ucontrol storage key and immediate exit tests Aaron M. Brown
@ 2026-11-10 11:16 ` Aaron M. Brown
2026-11-10 11:23 ` sashiko-bot
5 siblings, 1 reply; 13+ messages in thread
From: Aaron M. Brown @ 2026-11-10 11:16 UTC (permalink / raw)
To: kvm
Cc: Janosch Frank, Claudio Imbrenda, Christian Borntraeger,
linux-s390, linux-kselftest, Nitya Khamar
Add a test that injects a clock comparator interrupt into a ucontrol
VM. The guest sets the clock comparator far in the future, sets the
subclass mask, and waits with the external mask set.
The first KVM_RUN exits with ICPT_WAIT. Inject KVM_S390_INT_CLOCK_COMP
and run again. Check for ICPT_EXTREQ.
Co-developed-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Nitya Khamar <nkhamar@linux.ibm.com>
Signed-off-by: Aaron M. Brown <aaronmbr@linux.ibm.com>
---
tools/testing/selftests/kvm/s390/kvm_exit.c | 74 +++++++++++++++++++++
1 file changed, 74 insertions(+)
diff --git a/tools/testing/selftests/kvm/s390/kvm_exit.c b/tools/testing/selftests/kvm/s390/kvm_exit.c
index 4b9b30cd4e2a..0d2fd4f39a9c 100644
--- a/tools/testing/selftests/kvm/s390/kvm_exit.c
+++ b/tools/testing/selftests/kvm/s390/kvm_exit.c
@@ -42,6 +42,8 @@ int capget(cap_user_header_t header, cap_user_data_t data);
#define SSKE_SUBOPCODE 0x2b
#define SSKE_OPCODE 0xb2
#define PSW_WAIT_BIT_MASK (1ULL << (63 - 14))
+#define PSW_CLOCK_WAIT 0x0102000180000000ULL
+#define CLK_COMPARATOR_MASK_BIT (1ULL << 11)
#define PGM_CODE_GPA_ADDRESS 0x8e
#define PGM_CODE_MASK 0x7f
#define PGM_NEW_PSW_GPA 0x1d0
@@ -682,6 +684,73 @@ static bool test_immediate_exit(void)
return true;
}
+static void guestcode_clock_comparator(void)
+{
+ asm volatile(
+ /* Set SCKC to the maximum value so it cannot expire on its own */
+ "lghi %%r7, -1\n"
+ "stg %%r7, 0(%%r15)\n"
+ "sckc 0(%%r15)\n"
+ /* Enable clock comparator interrupt in CR0 (bit 52) */
+ "stctg %%c0, %%c0, 0(%%r15)\n"
+ "oi 6(%%r15), 0x8\n"
+ "lctlg %%c0, %%c0, 0(%%r15)\n"
+ /* Load enabled wait PSW: 64-bit, DAT off, wait bit, external interrupt enabled */
+ "larl %%r8, 1f\n"
+ "lpswe 0(%%r8)\n"
+ ".align 8\n"
+ "1: .quad %[wait_psw], 0\n"
+ :
+ : [wait_psw] "i" (PSW_CLOCK_WAIT)
+ : "r7", "r8", "memory"
+ );
+ GUEST_DONE();
+}
+
+static bool test_clock_comparator_interrupt(void)
+{
+ struct kvm_parameters param = {
+ .guest_code = guestcode_clock_comparator,
+ .manual_parameters.immediate_exit_condition = false,
+ };
+ struct kvm_s390_irq irq = {};
+ int rc;
+
+ if (!ucontrol_available())
+ return false;
+
+ ksft_print_msg("Testing Clock Comparator Interrupt Exit\n");
+ param = manual_kvm_creation_execution(param);
+
+ /* On a ucontrol VM, the guest's enabled wait exits to userspace as ICPT_WAIT. */
+ TEST_ASSERT(param.run->exit_reason == KVM_EXIT_S390_SIEIC,
+ "Expected SIEIC, got %u\n", param.run->exit_reason);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_WAIT,
+ "Expected ICPT_WAIT (0x1c), got 0x%x\n",
+ param.run->s390_sieic.icptcode);
+ TEST_ASSERT((param.run->s.regs.crs[0] & CLK_COMPARATOR_MASK_BIT) != 0,
+ "CR0 clock comparator bit not set, cr0=0x%llx\n",
+ param.run->s.regs.crs[0]);
+
+ /* Inject clock comparator interrupt as a ucontrol VMM would */
+ irq.type = KVM_S390_INT_CLOCK_COMP;
+ rc = ioctl(param.manual_parameters.vcpu_fd, KVM_S390_IRQ, &irq);
+ TEST_ASSERT(rc == 0, "KVM_S390_IRQ (clock comp) failed (%d)", errno);
+
+ /* With the interrupt pending and external interrupts enabled, expect ICPT_EXTREQ. */
+ rc = ioctl(param.manual_parameters.vcpu_fd, KVM_RUN, NULL);
+ TEST_ASSERT(rc == 0, "KVM_RUN (2) failed (%d)", errno);
+ TEST_ASSERT(param.run->exit_reason == KVM_EXIT_S390_SIEIC,
+ "Expected SIEIC on second run, got %u\n",
+ param.run->exit_reason);
+ TEST_ASSERT(param.run->s390_sieic.icptcode == ICPT_EXTREQ,
+ "Expected ICPT_EXTREQ (0x10), got 0x%x\n",
+ param.run->s390_sieic.icptcode);
+
+ manual_cleanup(param);
+ return true;
+}
+
static void test(void)
{
int i;
@@ -738,6 +807,11 @@ static void test(void)
.test = test_immediate_exit,
.skip_reason = "KVM_CAP_S390_UCONTROL unavailable or insufficient privilege"
},
+ {
+ .name = "Testing Clock Comparator External Interrupts",
+ .test = test_clock_comparator_interrupt,
+ .skip_reason = "KVM_CAP_S390_UCONTROL unavailable or insufficient privilege"
+ },
};
ksft_print_header();
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 13+ messages in thread