]> git.ipfire.org Git - thirdparty/kernel/stable.git/commitdiff
KVM: s390: selftests: Add selftest for the KVM_S390_KEYOP ioctl
authorClaudio Imbrenda <imbrenda@linux.ibm.com>
Wed, 4 Feb 2026 15:02:58 +0000 (16:02 +0100)
committerClaudio Imbrenda <imbrenda@linux.ibm.com>
Wed, 4 Feb 2026 16:00:10 +0000 (17:00 +0100)
This test allows to test the various storage key handling functions.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
tools/testing/selftests/kvm/Makefile.kvm
tools/testing/selftests/kvm/s390/keyop.c [new file with mode: 0644]

index ba5c2b643efaa263f90185b72fe59ecb0fcd6dbc..2e4774666723093dbe296fc9060ea19ce1d68a17 100644 (file)
@@ -199,6 +199,7 @@ 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 += s390/keyop
 TEST_GEN_PROGS_s390 += rseq_test
 
 TEST_GEN_PROGS_riscv = $(TEST_GEN_PROGS_COMMON)
diff --git a/tools/testing/selftests/kvm/s390/keyop.c b/tools/testing/selftests/kvm/s390/keyop.c
new file mode 100644 (file)
index 0000000..c7805e8
--- /dev/null
@@ -0,0 +1,299 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Test for s390x KVM_S390_KEYOP
+ *
+ * Copyright IBM Corp. 2026
+ *
+ * Authors:
+ *  Claudio Imbrenda <imbrenda@linux.ibm.com>
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include <linux/bits.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "kselftest.h"
+#include "processor.h"
+
+#define BUF_PAGES 128UL
+#define GUEST_PAGES 256UL
+
+#define BUF_START_GFN  (GUEST_PAGES - BUF_PAGES)
+#define BUF_START_ADDR (BUF_START_GFN << PAGE_SHIFT)
+
+#define KEY_BITS_ACC   0xf0
+#define KEY_BIT_F      0x08
+#define KEY_BIT_R      0x04
+#define KEY_BIT_C      0x02
+
+#define KEY_BITS_RC    (KEY_BIT_R | KEY_BIT_C)
+#define KEY_BITS_ALL   (KEY_BITS_ACC | KEY_BIT_F | KEY_BITS_RC)
+
+static unsigned char tmp[BUF_PAGES];
+static unsigned char old[BUF_PAGES];
+static unsigned char expected[BUF_PAGES];
+
+static int _get_skeys(struct kvm_vcpu *vcpu, unsigned char skeys[])
+{
+       struct kvm_s390_skeys skeys_ioctl = {
+               .start_gfn = BUF_START_GFN,
+               .count = BUF_PAGES,
+               .skeydata_addr = (unsigned long)skeys,
+       };
+
+       return __vm_ioctl(vcpu->vm, KVM_S390_GET_SKEYS, &skeys_ioctl);
+}
+
+static void get_skeys(struct kvm_vcpu *vcpu, unsigned char skeys[])
+{
+       int r = _get_skeys(vcpu, skeys);
+
+       TEST_ASSERT(!r, "Failed to get storage keys, r=%d", r);
+}
+
+static void set_skeys(struct kvm_vcpu *vcpu, unsigned char skeys[])
+{
+       struct kvm_s390_skeys skeys_ioctl = {
+               .start_gfn = BUF_START_GFN,
+               .count = BUF_PAGES,
+               .skeydata_addr = (unsigned long)skeys,
+       };
+       int r;
+
+       r = __vm_ioctl(vcpu->vm, KVM_S390_SET_SKEYS, &skeys_ioctl);
+       TEST_ASSERT(!r, "Failed to set storage keys, r=%d", r);
+}
+
+static int do_keyop(struct kvm_vcpu *vcpu, int op, unsigned long page_idx, unsigned char skey)
+{
+       struct kvm_s390_keyop keyop = {
+               .guest_addr = BUF_START_ADDR + page_idx * PAGE_SIZE,
+               .key = skey,
+               .operation = op,
+       };
+       int r;
+
+       r = __vm_ioctl(vcpu->vm, KVM_S390_KEYOP, &keyop);
+       TEST_ASSERT(!r, "Failed to perform keyop, r=%d", r);
+       TEST_ASSERT((keyop.key & 1) == 0,
+                   "Last bit of key is 1, should be 0! page %lu, new key=%#x, old key=%#x",
+                   page_idx, skey, keyop.key);
+
+       return keyop.key;
+}
+
+static void fault_in_buffer(struct kvm_vcpu *vcpu, int where, int cur_loc)
+{
+       unsigned long i;
+       int r;
+
+       if (where != cur_loc)
+               return;
+
+       for (i = 0; i < BUF_PAGES; i++) {
+               r = ioctl(vcpu->fd, KVM_S390_VCPU_FAULT, BUF_START_ADDR + i * PAGE_SIZE);
+               TEST_ASSERT(!r, "Faulting in buffer page %lu, r=%d", i, r);
+       }
+}
+
+static inline void set_pattern(unsigned char skeys[])
+{
+       int i;
+
+       for (i = 0; i < BUF_PAGES; i++)
+               skeys[i] = i << 1;
+}
+
+static void dump_sk(const unsigned char skeys[], const char *descr)
+{
+       int i, j;
+
+       fprintf(stderr, "# %s:\n", descr);
+       for (i = 0; i < BUF_PAGES; i += 32) {
+               fprintf(stderr, "# %3d: ", i);
+               for (j = 0; j < 32; j++)
+                       fprintf(stderr, "%02x ", skeys[i + j]);
+               fprintf(stderr, "\n");
+       }
+}
+
+static inline void compare(const unsigned char what[], const unsigned char expected[],
+                          const char *descr, int fault_in_loc)
+{
+       int i;
+
+       for (i = 0; i < BUF_PAGES; i++) {
+               if (expected[i] != what[i]) {
+                       dump_sk(expected, "Expected");
+                       dump_sk(what, "Got");
+               }
+               TEST_ASSERT(expected[i] == what[i],
+                           "%s! fault-in location %d, page %d, expected %#x, got %#x",
+                           descr, fault_in_loc, i, expected[i], what[i]);
+       }
+}
+
+static inline void clear_all(void)
+{
+       memset(tmp, 0, BUF_PAGES);
+       memset(old, 0, BUF_PAGES);
+       memset(expected, 0, BUF_PAGES);
+}
+
+static void test_init(struct kvm_vcpu *vcpu, int fault_in)
+{
+       /* Set all storage keys to zero */
+       fault_in_buffer(vcpu, fault_in, 1);
+       set_skeys(vcpu, expected);
+
+       fault_in_buffer(vcpu, fault_in, 2);
+       get_skeys(vcpu, tmp);
+       compare(tmp, expected, "Setting keys not zero", fault_in);
+
+       /* Set storage keys to a sequential pattern */
+       fault_in_buffer(vcpu, fault_in, 3);
+       set_pattern(expected);
+       set_skeys(vcpu, expected);
+
+       fault_in_buffer(vcpu, fault_in, 4);
+       get_skeys(vcpu, tmp);
+       compare(tmp, expected, "Setting storage keys failed", fault_in);
+}
+
+static void test_rrbe(struct kvm_vcpu *vcpu, int fault_in)
+{
+       unsigned char k;
+       int i;
+
+       /* Set storage keys to a sequential pattern */
+       fault_in_buffer(vcpu, fault_in, 1);
+       set_pattern(expected);
+       set_skeys(vcpu, expected);
+
+       /* Call the RRBE KEYOP ioctl on each page and verify the result */
+       fault_in_buffer(vcpu, fault_in, 2);
+       for (i = 0; i < BUF_PAGES; i++) {
+               k = do_keyop(vcpu, KVM_S390_KEYOP_RRBE, i, 0xff);
+               TEST_ASSERT((expected[i] & KEY_BITS_RC) == k,
+                           "Old R or C value mismatch! expected: %#x, got %#x",
+                           expected[i] & KEY_BITS_RC, k);
+               if (i == BUF_PAGES / 2)
+                       fault_in_buffer(vcpu, fault_in, 3);
+       }
+
+       for (i = 0; i < BUF_PAGES; i++)
+               expected[i] &= ~KEY_BIT_R;
+
+       /* Verify that only the R bit has been cleared */
+       fault_in_buffer(vcpu, fault_in, 4);
+       get_skeys(vcpu, tmp);
+       compare(tmp, expected, "New value mismatch", fault_in);
+}
+
+static void test_iske(struct kvm_vcpu *vcpu, int fault_in)
+{
+       int i;
+
+       /* Set storage keys to a sequential pattern */
+       fault_in_buffer(vcpu, fault_in, 1);
+       set_pattern(expected);
+       set_skeys(vcpu, expected);
+
+       /* Call the ISKE KEYOP ioctl on each page and verify the result */
+       fault_in_buffer(vcpu, fault_in, 2);
+       for (i = 0; i < BUF_PAGES; i++) {
+               tmp[i] = do_keyop(vcpu, KVM_S390_KEYOP_ISKE, i, 0xff);
+               if (i == BUF_PAGES / 2)
+                       fault_in_buffer(vcpu, fault_in, 3);
+       }
+       compare(tmp, expected, "Old value mismatch", fault_in);
+
+       /* Check storage keys have not changed */
+       fault_in_buffer(vcpu, fault_in, 4);
+       get_skeys(vcpu, tmp);
+       compare(tmp, expected, "Storage keys values changed", fault_in);
+}
+
+static void test_sske(struct kvm_vcpu *vcpu, int fault_in)
+{
+       int i;
+
+       /* Set storage keys to a sequential pattern */
+       fault_in_buffer(vcpu, fault_in, 1);
+       set_pattern(tmp);
+       set_skeys(vcpu, tmp);
+
+       /* Call the SSKE KEYOP ioctl on each page and verify the result */
+       fault_in_buffer(vcpu, fault_in, 2);
+       for (i = 0; i < BUF_PAGES; i++) {
+               expected[i] = ~tmp[i] & KEY_BITS_ALL;
+               /* Set the new storage keys to be the bit-inversion of the previous ones */
+               old[i] = do_keyop(vcpu, KVM_S390_KEYOP_SSKE, i, expected[i] | 1);
+               if (i == BUF_PAGES / 2)
+                       fault_in_buffer(vcpu, fault_in, 3);
+       }
+       compare(old, tmp, "Old value mismatch", fault_in);
+
+       /* Verify that the storage keys have been set correctly */
+       fault_in_buffer(vcpu, fault_in, 4);
+       get_skeys(vcpu, tmp);
+       compare(tmp, expected, "New value mismatch", fault_in);
+}
+
+static struct testdef {
+       const char *name;
+       void (*test)(struct kvm_vcpu *vcpu, int fault_in_location);
+       int n_fault_in_locations;
+} testplan[] = {
+       { "Initialization", test_init, 5 },
+       { "RRBE", test_rrbe, 5 },
+       { "ISKE", test_iske, 5 },
+       { "SSKE", test_sske, 5 },
+};
+
+static void run_test(void (*the_test)(struct kvm_vcpu *, int), int fault_in_location)
+{
+       struct kvm_vcpu *vcpu;
+       struct kvm_vm *vm;
+       int r;
+
+       vm = vm_create_barebones();
+       vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, GUEST_PAGES, 0);
+       vcpu = __vm_vcpu_add(vm, 0);
+
+       r = _get_skeys(vcpu, tmp);
+       TEST_ASSERT(r == KVM_S390_GET_SKEYS_NONE,
+                   "Storage keys are not disabled initially, r=%d", r);
+
+       clear_all();
+
+       the_test(vcpu, fault_in_location);
+
+       kvm_vm_free(vm);
+}
+
+int main(int argc, char *argv[])
+{
+       int i, f;
+
+       TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_KEYOP));
+       TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_UCONTROL));
+
+       ksft_print_header();
+       for (i = 0, f = 0; i < ARRAY_SIZE(testplan); i++)
+               f += testplan[i].n_fault_in_locations;
+       ksft_set_plan(f);
+
+       for (i = 0; i < ARRAY_SIZE(testplan); i++) {
+               for (f = 0; f < testplan[i].n_fault_in_locations; f++) {
+                       run_test(testplan[i].test, f);
+                       ksft_test_result_pass("%s (fault-in location %d)\n", testplan[i].name, f);
+               }
+       }
+
+       ksft_finished();        /* Print results and exit() accordingly */
+}