From: Isaku Yamahata <isaku.yamahata@intel.com>
Add a test case to exercise KVM_PRE_FAULT_MEMORY and run the guest to access the
pre-populated area. It tests KVM_PRE_FAULT_MEMORY ioctl for KVM_X86_DEFAULT_VM
and KVM_X86_SW_PROTECTED_VM.
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Message-ID: <32427791ef42e5efaafb05d2ac37fa4372715f47.1712785629.git.isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
tools/include/uapi/linux/kvm.h | 8 +
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/pre_fault_memory_test.c | 146 ++++++++++++++++++
3 files changed, 155 insertions(+)
create mode 100644 tools/testing/selftests/kvm/pre_fault_memory_test.c
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index c3308536482b..4d66d8afdcd1 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -2227,4 +2227,12 @@ struct kvm_create_guest_memfd {
__u64 reserved[6];
};
+#define KVM_PRE_FAULT_MEMORY _IOWR(KVMIO, 0xd5, struct kvm_pre_fault_memory)
+
+struct kvm_pre_fault_memory {
+ __u64 gpa;
+ __u64 size;
+ __u64 flags;
+};
+
#endif /* __LINUX_KVM_H */
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 871e2de3eb05..61d581a4bab4 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -144,6 +144,7 @@ TEST_GEN_PROGS_x86_64 += set_memory_region_test
TEST_GEN_PROGS_x86_64 += steal_time
TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
TEST_GEN_PROGS_x86_64 += system_counter_offset_test
+TEST_GEN_PROGS_x86_64 += pre_fault_memory_test
# Compiled outputs used by test targets
TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
diff --git a/tools/testing/selftests/kvm/pre_fault_memory_test.c b/tools/testing/selftests/kvm/pre_fault_memory_test.c
new file mode 100644
index 000000000000..e56eed2c1f05
--- /dev/null
+++ b/tools/testing/selftests/kvm/pre_fault_memory_test.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024, Intel, Inc
+ *
+ * Author:
+ * Isaku Yamahata <isaku.yamahata at gmail.com>
+ */
+#include <linux/sizes.h>
+
+#include <test_util.h>
+#include <kvm_util.h>
+#include <processor.h>
+
+/* Arbitrarily chosen values */
+#define TEST_SIZE (SZ_2M + PAGE_SIZE)
+#define TEST_NPAGES (TEST_SIZE / PAGE_SIZE)
+#define TEST_SLOT 10
+
+static void guest_code(uint64_t base_gpa)
+{
+ volatile uint64_t val __used;
+ int i;
+
+ for (i = 0; i < TEST_NPAGES; i++) {
+ uint64_t *src = (uint64_t *)(base_gpa + i * PAGE_SIZE);
+
+ val = *src;
+ }
+
+ GUEST_DONE();
+}
+
+static void pre_fault_memory(struct kvm_vcpu *vcpu, u64 gpa, u64 size,
+ u64 left)
+{
+ struct kvm_pre_fault_memory range = {
+ .gpa = gpa,
+ .size = size,
+ .flags = 0,
+ };
+ u64 prev;
+ int ret, save_errno;
+
+ do {
+ prev = range.size;
+ ret = __vcpu_ioctl(vcpu, KVM_PRE_FAULT_MEMORY, &range);
+ save_errno = errno;
+ TEST_ASSERT((range.size < prev) ^ (ret < 0),
+ "%sexpecting range.size to change on %s",
+ ret < 0 ? "not " : "",
+ ret < 0 ? "failure" : "success");
+ } while (ret >= 0 ? range.size : save_errno == EINTR);
+
+ TEST_ASSERT(range.size == left,
+ "Completed with %lld bytes left, expected %" PRId64,
+ range.size, left);
+
+ if (left == 0)
+ __TEST_ASSERT_VM_VCPU_IOCTL(!ret, "KVM_PRE_FAULT_MEMORY", ret, vcpu->vm);
+ else
+ /* No memory slot causes RET_PF_EMULATE. it results in -ENOENT. */
+ __TEST_ASSERT_VM_VCPU_IOCTL(ret && save_errno == ENOENT,
+ "KVM_PRE_FAULT_MEMORY", ret, vcpu->vm);
+}
+
+static void __test_pre_fault_memory(unsigned long vm_type, bool private)
+{
+ const struct vm_shape shape = {
+ .mode = VM_MODE_DEFAULT,
+ .type = vm_type,
+ };
+ struct kvm_vcpu *vcpu;
+ struct kvm_run *run;
+ struct kvm_vm *vm;
+ struct ucall uc;
+
+ uint64_t guest_test_phys_mem;
+ uint64_t guest_test_virt_mem;
+ uint64_t alignment, guest_page_size;
+
+ vm = vm_create_shape_with_one_vcpu(shape, &vcpu, guest_code);
+
+ alignment = guest_page_size = vm_guest_mode_params[VM_MODE_DEFAULT].page_size;
+ guest_test_phys_mem = (vm->max_gfn - TEST_NPAGES) * guest_page_size;
+#ifdef __s390x__
+ alignment = max(0x100000UL, guest_page_size);
+#else
+ alignment = SZ_2M;
+#endif
+ guest_test_phys_mem = align_down(guest_test_phys_mem, alignment);
+ guest_test_virt_mem = guest_test_phys_mem;
+
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+ guest_test_phys_mem, TEST_SLOT, TEST_NPAGES,
+ private ? KVM_MEM_GUEST_MEMFD : 0);
+ virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, TEST_NPAGES);
+
+ if (private)
+ vm_mem_set_private(vm, guest_test_phys_mem, TEST_SIZE);
+ pre_fault_memory(vcpu, guest_test_phys_mem, SZ_2M, 0);
+ pre_fault_memory(vcpu, guest_test_phys_mem + SZ_2M, PAGE_SIZE * 2, PAGE_SIZE);
+ pre_fault_memory(vcpu, guest_test_phys_mem + TEST_SIZE, PAGE_SIZE, PAGE_SIZE);
+
+ vcpu_args_set(vcpu, 1, guest_test_virt_mem);
+ vcpu_run(vcpu);
+
+ run = vcpu->run;
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Wanted KVM_EXIT_IO, got exit reason: %u (%s)",
+ run->exit_reason, exit_reason_str(run->exit_reason));
+
+ switch (get_ucall(vcpu, &uc)) {
+ case UCALL_ABORT:
+ REPORT_GUEST_ASSERT(uc);
+ break;
+ case UCALL_DONE:
+ break;
+ default:
+ TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
+ break;
+ }
+
+ kvm_vm_free(vm);
+}
+
+static void test_pre_fault_memory(unsigned long vm_type, bool private)
+{
+ if (vm_type && !(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(vm_type))) {
+ pr_info("Skipping tests for vm_type 0x%lx\n", vm_type);
+ return;
+ }
+
+ __test_pre_fault_memory(vm_type, private);
+}
+
+int main(int argc, char *argv[])
+{
+ TEST_REQUIRE(kvm_check_cap(KVM_CAP_PRE_FAULT_MEMORY));
+
+ test_pre_fault_memory(0, false);
+#ifdef __x86_64__
+ test_pre_fault_memory(KVM_X86_SW_PROTECTED_VM, false);
+ test_pre_fault_memory(KVM_X86_SW_PROTECTED_VM, true);
+#endif
+ return 0;
+}
--
2.43.0On 4/19/2024 4:59 PM, Paolo Bonzini wrote:
...
> +static void __test_pre_fault_memory(unsigned long vm_type, bool private)
> +{
> + const struct vm_shape shape = {
> + .mode = VM_MODE_DEFAULT,
> + .type = vm_type,
> + };
> + struct kvm_vcpu *vcpu;
> + struct kvm_run *run;
> + struct kvm_vm *vm;
> + struct ucall uc;
> +
> + uint64_t guest_test_phys_mem;
> + uint64_t guest_test_virt_mem;
> + uint64_t alignment, guest_page_size;
> +
> + vm = vm_create_shape_with_one_vcpu(shape, &vcpu, guest_code);
> +
> + alignment = guest_page_size = vm_guest_mode_params[VM_MODE_DEFAULT].page_size;
> + guest_test_phys_mem = (vm->max_gfn - TEST_NPAGES) * guest_page_size;
> +#ifdef __s390x__
> + alignment = max(0x100000UL, guest_page_size);
> +#else
> + alignment = SZ_2M;
> +#endif
> + guest_test_phys_mem = align_down(guest_test_phys_mem, alignment);
> + guest_test_virt_mem = guest_test_phys_mem;
guest_test_virt_mem cannot be assigned as guest_test_phys_mem, which
leads to following virt_map() fails with
==== Test Assertion Failure ====
lib/x86_64/processor.c:197: sparsebit_is_set(vm->vpages_valid, (vaddr
>> vm->page_shift))
pid=4773 tid=4773 errno=0 - Success
1 0x000000000040f55c: __virt_pg_map at processor.c:197
2 0x000000000040605e: virt_pg_map at kvm_util_base.h:1065
3 (inlined by) virt_map at kvm_util.c:1571
4 0x0000000000402b75: __test_pre_fault_memory at
pre_fault_memory_test.c:96
5 0x000000000040246e: test_pre_fault_memory at
pre_fault_memory_test.c:133 (discriminator 3)
6 (inlined by) main at pre_fault_memory_test.c:140 (discriminator 3)
7 0x00007fcb68429d8f: ?? ??:0
8 0x00007fcb68429e3f: ?? ??:0
9 0x00000000004024e4: _start at ??:?
Invalid virtual address, vaddr: 0xfffffffc00000
> +
> + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
> + guest_test_phys_mem, TEST_SLOT, TEST_NPAGES,
> + private ? KVM_MEM_GUEST_MEMFD : 0);
> + virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, TEST_NPAGES);
On 4/23/2024 11:18 PM, Xiaoyao Li wrote:
> On 4/19/2024 4:59 PM, Paolo Bonzini wrote:
>
> ...
>
>> +static void __test_pre_fault_memory(unsigned long vm_type, bool private)
>> +{
>> + const struct vm_shape shape = {
>> + .mode = VM_MODE_DEFAULT,
>> + .type = vm_type,
>> + };
>> + struct kvm_vcpu *vcpu;
>> + struct kvm_run *run;
>> + struct kvm_vm *vm;
>> + struct ucall uc;
>> +
>> + uint64_t guest_test_phys_mem;
>> + uint64_t guest_test_virt_mem;
>> + uint64_t alignment, guest_page_size;
>> +
>> + vm = vm_create_shape_with_one_vcpu(shape, &vcpu, guest_code);
>> +
>> + alignment = guest_page_size =
>> vm_guest_mode_params[VM_MODE_DEFAULT].page_size;
>> + guest_test_phys_mem = (vm->max_gfn - TEST_NPAGES) * guest_page_size;
>> +#ifdef __s390x__
>> + alignment = max(0x100000UL, guest_page_size);
>> +#else
>> + alignment = SZ_2M;
>> +#endif
>> + guest_test_phys_mem = align_down(guest_test_phys_mem, alignment);
>> + guest_test_virt_mem = guest_test_phys_mem;
>
> guest_test_virt_mem cannot be assigned as guest_test_phys_mem, which
> leads to following virt_map() fails with
The root cause is that vm->pa_bits is 52 while vm->va_bits is 48. So
vm->max_gfn is beyond the capability of va space
> ==== Test Assertion Failure ====
> lib/x86_64/processor.c:197: sparsebit_is_set(vm->vpages_valid, (vaddr
> >> vm->page_shift))
> pid=4773 tid=4773 errno=0 - Success
> 1 0x000000000040f55c: __virt_pg_map at processor.c:197
> 2 0x000000000040605e: virt_pg_map at kvm_util_base.h:1065
> 3 (inlined by) virt_map at kvm_util.c:1571
> 4 0x0000000000402b75: __test_pre_fault_memory at
> pre_fault_memory_test.c:96
> 5 0x000000000040246e: test_pre_fault_memory at
> pre_fault_memory_test.c:133 (discriminator 3)
> 6 (inlined by) main at pre_fault_memory_test.c:140
> (discriminator 3)
> 7 0x00007fcb68429d8f: ?? ??:0
> 8 0x00007fcb68429e3f: ?? ??:0
> 9 0x00000000004024e4: _start at ??:?
> Invalid virtual address, vaddr: 0xfffffffc00000
>
>> +
>> + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
>> + guest_test_phys_mem, TEST_SLOT, TEST_NPAGES,
>> + private ? KVM_MEM_GUEST_MEMFD : 0);
>> + virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, TEST_NPAGES);
>
>
>
>
>
On Fri, Apr 19, 2024 at 04:59:27AM -0400,
Paolo Bonzini <pbonzini@redhat.com> wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> Add a test case to exercise KVM_PRE_FAULT_MEMORY and run the guest to access the
> pre-populated area. It tests KVM_PRE_FAULT_MEMORY ioctl for KVM_X86_DEFAULT_VM
> and KVM_X86_SW_PROTECTED_VM.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> Message-ID: <32427791ef42e5efaafb05d2ac37fa4372715f47.1712785629.git.isaku.yamahata@intel.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> tools/include/uapi/linux/kvm.h | 8 +
> tools/testing/selftests/kvm/Makefile | 1 +
> .../selftests/kvm/pre_fault_memory_test.c | 146 ++++++++++++++++++
> 3 files changed, 155 insertions(+)
> create mode 100644 tools/testing/selftests/kvm/pre_fault_memory_test.c
>
> diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
> index c3308536482b..4d66d8afdcd1 100644
> --- a/tools/include/uapi/linux/kvm.h
> +++ b/tools/include/uapi/linux/kvm.h
> @@ -2227,4 +2227,12 @@ struct kvm_create_guest_memfd {
> __u64 reserved[6];
> };
>
> +#define KVM_PRE_FAULT_MEMORY _IOWR(KVMIO, 0xd5, struct kvm_pre_fault_memory)
> +
> +struct kvm_pre_fault_memory {
> + __u64 gpa;
> + __u64 size;
> + __u64 flags;
nitpick: catch up for struct update.
+ __u64 padding[5];
> +};
> +
> #endif /* __LINUX_KVM_H */
--
Isaku Yamahata <isaku.yamahata@intel.com>
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