Commit 2feabb85 authored by Chao Peng's avatar Chao Peng Committed by Paolo Bonzini
Browse files

KVM: selftests: Expand set_memory_region_test to validate guest_memfd() 



Expand set_memory_region_test to exercise various positive and negative
testcases for private memory.

 - Non-guest_memfd() file descriptor for private memory
 - guest_memfd() from different VM
 - Overlapping bindings
 - Unaligned bindings

Signed-off-by: default avatarChao Peng <chao.p.peng@linux.intel.com>
Co-developed-by: default avatarAckerley Tng <ackerleytng@google.com>
Signed-off-by: default avatarAckerley Tng <ackerleytng@google.com>
[sean: trim the testcases to remove duplicate coverage]
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20231027182217.3615211-34-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent e6f4f345

tools/testing/selftests/kvm/include/kvm_util_base.h

+12 −0
Original line number Diff line number Diff line
@@ -819,6 +819,18 @@ static inline struct kvm_vm *vm_create_barebones(void) 
	return ____vm_create(VM_SHAPE_DEFAULT);

}



#ifdef __x86_64__

static inline struct kvm_vm *vm_create_barebones_protected_vm(void)

{

	const struct vm_shape shape = {

		.mode = VM_MODE_DEFAULT,

		.type = KVM_X86_SW_PROTECTED_VM,

	};



	return ____vm_create(shape);

}

#endif



static inline struct kvm_vm *vm_create(uint32_t nr_runnable_vcpus)

{

	return __vm_create(VM_SHAPE_DEFAULT, nr_runnable_vcpus, 0);

tools/testing/selftests/kvm/set_memory_region_test.c

+102 −2
Original line number Diff line number Diff line
@@ -385,13 +385,105 @@ static void test_add_max_memory_regions(void) 
	kvm_vm_free(vm);

}





#ifdef __x86_64__

static void test_invalid_guest_memfd(struct kvm_vm *vm, int memfd,

				     size_t offset, const char *msg)

{

	int r = __vm_set_user_memory_region2(vm, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

					     MEM_REGION_GPA, MEM_REGION_SIZE,

					     0, memfd, offset);

	TEST_ASSERT(r == -1 && errno == EINVAL, "%s", msg);

}



static void test_add_private_memory_region(void)

{

	struct kvm_vm *vm, *vm2;

	int memfd, i;



	pr_info("Testing ADD of KVM_MEM_GUEST_MEMFD memory regions\n");



	vm = vm_create_barebones_protected_vm();



	test_invalid_guest_memfd(vm, vm->kvm_fd, 0, "KVM fd should fail");

	test_invalid_guest_memfd(vm, vm->fd, 0, "VM's fd should fail");



	memfd = kvm_memfd_alloc(MEM_REGION_SIZE, false);

	test_invalid_guest_memfd(vm, memfd, 0, "Regular memfd() should fail");

	close(memfd);



	vm2 = vm_create_barebones_protected_vm();

	memfd = vm_create_guest_memfd(vm2, MEM_REGION_SIZE, 0);

	test_invalid_guest_memfd(vm, memfd, 0, "Other VM's guest_memfd() should fail");



	vm_set_user_memory_region2(vm2, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

				   MEM_REGION_GPA, MEM_REGION_SIZE, 0, memfd, 0);

	close(memfd);

	kvm_vm_free(vm2);



	memfd = vm_create_guest_memfd(vm, MEM_REGION_SIZE, 0);

	for (i = 1; i < PAGE_SIZE; i++)

		test_invalid_guest_memfd(vm, memfd, i, "Unaligned offset should fail");



	vm_set_user_memory_region2(vm, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

				   MEM_REGION_GPA, MEM_REGION_SIZE, 0, memfd, 0);

	close(memfd);



	kvm_vm_free(vm);

}



static void test_add_overlapping_private_memory_regions(void)

{

	struct kvm_vm *vm;

	int memfd;

	int r;



	pr_info("Testing ADD of overlapping KVM_MEM_GUEST_MEMFD memory regions\n");



	vm = vm_create_barebones_protected_vm();



	memfd = vm_create_guest_memfd(vm, MEM_REGION_SIZE * 4, 0);



	vm_set_user_memory_region2(vm, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

				   MEM_REGION_GPA, MEM_REGION_SIZE * 2, 0, memfd, 0);



	vm_set_user_memory_region2(vm, MEM_REGION_SLOT + 1, KVM_MEM_GUEST_MEMFD,

				   MEM_REGION_GPA * 2, MEM_REGION_SIZE * 2,

				   0, memfd, MEM_REGION_SIZE * 2);



	/*

	 * Delete the first memslot, and then attempt to recreate it except

	 * with a "bad" offset that results in overlap in the guest_memfd().

	 */

	vm_set_user_memory_region2(vm, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

				   MEM_REGION_GPA, 0, NULL, -1, 0);



	/* Overlap the front half of the other slot. */

	r = __vm_set_user_memory_region2(vm, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

					 MEM_REGION_GPA * 2 - MEM_REGION_SIZE,

					 MEM_REGION_SIZE * 2,

					 0, memfd, 0);

	TEST_ASSERT(r == -1 && errno == EEXIST, "%s",

		    "Overlapping guest_memfd() bindings should fail with EEXIST");



	/* And now the back half of the other slot. */

	r = __vm_set_user_memory_region2(vm, MEM_REGION_SLOT, KVM_MEM_GUEST_MEMFD,

					 MEM_REGION_GPA * 2 + MEM_REGION_SIZE,

					 MEM_REGION_SIZE * 2,

					 0, memfd, 0);

	TEST_ASSERT(r == -1 && errno == EEXIST, "%s",

		    "Overlapping guest_memfd() bindings should fail with EEXIST");



	close(memfd);

	kvm_vm_free(vm);

}

#endif



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

{

#ifdef __x86_64__

	int i, loops;

#endif



#ifdef __x86_64__

	/*

	 * FIXME: the zero-memslot test fails on aarch64 and s390x because

	 * KVM_RUN fails with ENOEXEC or EFAULT.
@@ -402,6 +494,14 @@ int main(int argc, char *argv[]) 
	test_add_max_memory_regions();



#ifdef __x86_64__

	if (kvm_has_cap(KVM_CAP_GUEST_MEMFD) &&

	    (kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM))) {

		test_add_private_memory_region();

		test_add_overlapping_private_memory_regions();

	} else {

		pr_info("Skipping tests for KVM_MEM_GUEST_MEMFD memory regions\n");

	}



	if (argc > 1)

		loops = atoi_positive("Number of iterations", argv[1]);

	else