Re: [PATCH] KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl

On 29.08.19 12:20, Thomas Huth wrote:

Check that we can write and read the guest memory with this s390x ioctl, and that some error cases are handled correctly.

Signed-off-by: Thomas Huth thuth@redhat.com

This test uses the ucall() interface, so this patch needs to be applied on top of my "Implement ucall() for s390x" patch (which is not merged to master yet)

Looks good and tested. Will apply to kvms390/next after some more testing.

tools/testing/selftests/kvm/Makefile | 1 + tools/testing/selftests/kvm/s390x/memop.c | 155 ++++++++++++++++++++++ 2 files changed, 156 insertions(+) create mode 100644 tools/testing/selftests/kvm/s390x/memop.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 1b48a94b4350..62c591f87dab 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -32,6 +32,7 @@ TEST_GEN_PROGS_aarch64 += clear_dirty_log_test TEST_GEN_PROGS_aarch64 += dirty_log_test TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus +TEST_GEN_PROGS_s390x = s390x/memop TEST_GEN_PROGS_s390x += s390x/sync_regs_test TEST_GEN_PROGS_s390x += dirty_log_test TEST_GEN_PROGS_s390x += kvm_create_max_vcpus diff --git a/tools/testing/selftests/kvm/s390x/memop.c b/tools/testing/selftests/kvm/s390x/memop.c new file mode 100644 index 000000000000..25b100d9fdda --- /dev/null +++ b/tools/testing/selftests/kvm/s390x/memop.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/*

• • Test for s390x KVM_S390_MEM_OP
• • Copyright (C) 2019, Red Hat, Inc.
• */

+#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h>

+#include "test_util.h" +#include "kvm_util.h"

+#define VCPU_ID 1

+static uint8_t mem1[65536]; +static uint8_t mem2[65536];

+static void guest_code(void) +{

• int i;
• for (;;) {

• for (i = 0; i < sizeof(mem2); i++)
  

• 	mem2[i] = mem1[i];
  

• GUEST_SYNC(0);
  

• }

+}

+int main(int argc, char *argv[]) +{

• struct kvm_vm *vm;
• struct kvm_run *run;
• struct kvm_s390_mem_op ksmo;
• int rv, i, maxsize;
• setbuf(stdout, NULL); /* Tell stdout not to buffer its content */
• maxsize = kvm_check_cap(KVM_CAP_S390_MEM_OP);
• if (!maxsize) {

• fprintf(stderr, "CAP_S390_MEM_OP not supported -> skip test\n");
  

• exit(KSFT_SKIP);
  

• }
• if (maxsize > sizeof(mem1))

• maxsize = sizeof(mem1);
  

• /* Create VM */
• vm = vm_create_default(VCPU_ID, 0, guest_code);
• run = vcpu_state(vm, VCPU_ID);
• for (i = 0; i < sizeof(mem1); i++)

• mem1[i] = i * i + i;
  

• /* Set the first array */
• ksmo.gaddr = addr_gva2gpa(vm, (uintptr_t)mem1);
• ksmo.flags = 0;
• ksmo.size = maxsize;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
• ksmo.buf = (uintptr_t)mem1;
• ksmo.ar = 0;
• vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• /* Let the guest code copy the first array to the second */
• vcpu_run(vm, VCPU_ID);
• TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,

•     "Unexpected exit reason: %u (%s)\n",
  

•     run->exit_reason,
  

•     exit_reason_str(run->exit_reason));
  

• memset(mem2, 0xaa, sizeof(mem2));
• /* Get the second array */
• ksmo.gaddr = (uintptr_t)mem2;
• ksmo.flags = 0;
• ksmo.size = maxsize;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_READ;
• ksmo.buf = (uintptr_t)mem2;
• ksmo.ar = 0;
• vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(!memcmp(mem1, mem2, maxsize),

•     "Memory contents do not match!");
  

• /* Check error conditions - first bad size: */
• ksmo.gaddr = (uintptr_t)mem1;
• ksmo.flags = 0;
• ksmo.size = -1;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
• ksmo.buf = (uintptr_t)mem1;
• ksmo.ar = 0;
• rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(rv == -1 && errno == E2BIG, "ioctl allows insane sizes");
• /* Bad flags: */
• ksmo.gaddr = (uintptr_t)mem1;
• ksmo.flags = -1;
• ksmo.size = maxsize;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
• ksmo.buf = (uintptr_t)mem1;
• ksmo.ar = 0;
• rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows all flags?");
• /* Bad operation: */
• ksmo.gaddr = (uintptr_t)mem1;
• ksmo.flags = 0;
• ksmo.size = maxsize;
• ksmo.op = -1;
• ksmo.buf = (uintptr_t)mem1;
• ksmo.ar = 0;
• rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows all flags?");
• /* Bad guest address: */
• ksmo.gaddr = ~0xfffUL;
• ksmo.flags = KVM_S390_MEMOP_F_CHECK_ONLY;
• ksmo.size = maxsize;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
• ksmo.buf = (uintptr_t)mem1;
• ksmo.ar = 0;
• rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(rv > 0, "ioctl does not report bad guest memory access");
• /* Bad host address: */
• ksmo.gaddr = (uintptr_t)mem1;
• ksmo.flags = 0;
• ksmo.size = maxsize;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
• ksmo.buf = 0;
• ksmo.ar = 0;
• rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(rv == -1 && errno == EFAULT,

•     "ioctl does not report bad host memory address");
  

• /* Bad access register: */
• run->psw_mask &= ~(3UL << (63 - 17));
• run->psw_mask |= 1UL << (63 - 17); /* Enable AR mode */
• vcpu_run(vm, VCPU_ID); /* To sync new state to SIE block */
• ksmo.gaddr = (uintptr_t)mem1;
• ksmo.flags = 0;
• ksmo.size = maxsize;
• ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
• ksmo.buf = (uintptr_t)mem1;
• ksmo.ar = 17;
• rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
• TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows ARs > 15");
• run->psw_mask &= ~(3UL << (63 - 17)); /* Disable AR mode */
• vcpu_run(vm, VCPU_ID); /* Run to sync new state */
• kvm_vm_free(vm);
• return 0;

+}