2019-08-29 12:15:51

by Thomas Huth

[permalink] [raw]
Subject: [PATCH v2] KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl

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 <[email protected]>
---
v2: Check the ioctl also with "size" set to 0

tools/testing/selftests/kvm/Makefile | 1 +
tools/testing/selftests/kvm/s390x/memop.c | 165 ++++++++++++++++++++++
2 files changed, 166 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..e6a65f9e48ca
--- /dev/null
+++ b/tools/testing/selftests/kvm/s390x/memop.c
@@ -0,0 +1,165 @@
+// 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");
+
+ /* Zero size: */
+ ksmo.gaddr = (uintptr_t)mem1;
+ ksmo.flags = 0;
+ ksmo.size = 0;
+ 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, "ioctl allows 0 as size");
+
+ /* 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;
+}
--
2.18.1


2019-08-29 12:22:50

by Janosch Frank

[permalink] [raw]
Subject: Re: [PATCH v2] KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl

On 8/29/19 2:14 PM, 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 <[email protected]>
> ---
> v2: Check the ioctl also with "size" set to 0
>
[...]
> +
> + /* Zero size: */
> + ksmo.gaddr = (uintptr_t)mem1;
> + ksmo.flags = 0;
> + ksmo.size = 0;
> + 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, "ioctl allows 0 as size");

Test for errno == -EINVAL?

> +
> + /* 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?");

Wrong report string





Attachments:
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2019-08-29 12:30:24

by Thomas Huth

[permalink] [raw]
Subject: Re: [PATCH v2] KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl

On 29/08/2019 14.21, Janosch Frank wrote:
> On 8/29/19 2:14 PM, 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 <[email protected]>
>> ---
>> v2: Check the ioctl also with "size" set to 0
>>
> [...]
>> +
>> + /* Zero size: */
>> + ksmo.gaddr = (uintptr_t)mem1;
>> + ksmo.flags = 0;
>> + ksmo.size = 0;
>> + 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, "ioctl allows 0 as size");
>
> Test for errno == -EINVAL?

Assuming that my "Test for bad access register and size at the start
of S390_MEM_OP" goes in first, yes, I can add that check.

Otherwise, the current kernel still returns ENOMEM.

>> +
>> + /* 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?");
>
> Wrong report string
Oops, stupid copy-n-paste bug ... I'll fix it in v3...

Thanks,
Thomas


Attachments:
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2019-08-30 09:46:27

by David Hildenbrand

[permalink] [raw]
Subject: Re: [PATCH v2] KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl

On 29.08.19 14:14, 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 <[email protected]>
> ---
> v2: Check the ioctl also with "size" set to 0
>
> tools/testing/selftests/kvm/Makefile | 1 +
> tools/testing/selftests/kvm/s390x/memop.c | 165 ++++++++++++++++++++++
> 2 files changed, 166 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..e6a65f9e48ca
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/s390x/memop.c
> @@ -0,0 +1,165 @@
> +// 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");
> +
> + /* Zero size: */
> + ksmo.gaddr = (uintptr_t)mem1;
> + ksmo.flags = 0;
> + ksmo.size = 0;
> + 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, "ioctl allows 0 as size");
> +
> + /* 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;
> +}
>

Had a quick glimpse and besides the two things Janosch mentioned,
nothing jumped at me.

--

Thanks,

David / dhildenb