[RFC V2 PATCH 6/8] selftests: kvm: Add KVM_HC_MAP_GPA_RANGE hypercall test

Vishal Annapurve
2022-05-11T00:08:49Z

Add test to exercise explicit memory conversion path using
KVM_HC_MAP_GPA_RANGE hypercall.

Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
tools/testing/selftests/kvm/priv_memfd_test.c | 148 ++++++++++++++++++
1 file changed, 148 insertions(+)

diff --git a/tools/testing/selftests/kvm/priv_memfd_test.c b/tools/testing/selftests/kvm/priv_memfd_test.c
index f6f6b064a101..c2ea8f67337c 100644
--- a/tools/testing/selftests/kvm/priv_memfd_test.c
+++ b/tools/testing/selftests/kvm/priv_memfd_test.c
@@ -574,6 +574,149 @@ static void spat_guest_code(void)
GUEST_DONE();
}

+/* Test to verify guest private, shared, private accesses on memory with
+ * following steps:
+ * 1) Upon entry, guest signals VMM that it has started.
+ * 2) VMM initializes the shared memory with known pattern and continues guest
+ * execution
+ * 3) Guest writes the private memory privately via a known pattern and
+ * signals VMM
+ * 4) VMM reads the shared memory and verifies that it's same as whats written
+ * in step 2 and continues guest execution
+ * 5) Guest reads the private memory privately and verifies that the contents
+ * are same as written in step 3.
+ * 6) Guest invokes KVM_HC_MAP_GPA_RANGE to map the hpa range as shared
+ * and marks the range to be accessed via shared access.
+ * 7) Guest does a shared access to shared memory and verifies that the
+ * contents are same as written in step 2.
+ * 8) Guest writes known pattern to test memory and signals VMM.
+ * 9) VMM verifies the memory contents to be same as written by guest in step
+ * 8
+ * 10) Guest invokes KVM_HC_MAP_GPA_RANGE to map the hpa range as private
+ * and marks the range to be accessed via private access.
+ * 11) Guest writes a known pattern to the test memory and signals VMM.
+ * 12) VMM verifies the memory contents to be same as written by guest in step
+ * 8 and continues guest execution.
+ * 13) Guest verififes the memory pattern to be same as written in step 11.
+ */
+#define PSPAHCT_ID 6
+#define PSPAHCT_DESC "PrivateSharedPrivateAccessHyperCallTest"
+
+#define PSPAHCT_GUEST_STARTED 0ULL
+#define PSPAHCT_GUEST_PRIVATE_MEM_UPDATED 1ULL
+#define PSPAHCT_GUEST_SHARED_MEM_UPDATED 2ULL
+#define PSPAHCT_GUEST_PRIVATE_MEM_UPDATED2 3ULL
+
+static bool pspahct_handle_vm_stage(struct kvm_vm *vm,
+ void *test_info,
+ uint64_t stage)
+{
+ void *shared_mem = ((struct test_run_helper *)test_info)->shared_mem;
+
+ switch (stage) {
+ case PSPAHCT_GUEST_STARTED: {
+ /* Initialize the contents of shared memory */
+ TEST_ASSERT(do_mem_op(SET_PAT, shared_mem,
+ TEST_MEM_DATA_PAT1, TEST_MEM_SIZE),
+ "Shared memory update failed");
+ VM_STAGE_PROCESSED(PSPAHCT_GUEST_STARTED);
+ break;
+ }
+ case PSPAHCT_GUEST_PRIVATE_MEM_UPDATED: {
+ /* verify data to be same as what guest wrote earlier */
+ TEST_ASSERT(do_mem_op(VERIFY_PAT, shared_mem,
+ TEST_MEM_DATA_PAT1, TEST_MEM_SIZE),
+ "Shared memory view mismatch");
+ VM_STAGE_PROCESSED(PSPAHCT_GUEST_PRIVATE_MEM_UPDATED);
+ break;
+ }
+ case PSPAHCT_GUEST_SHARED_MEM_UPDATED: {
+ /* verify data to be same as what guest wrote earlier */
+ TEST_ASSERT(do_mem_op(VERIFY_PAT, shared_mem,
+ TEST_MEM_DATA_PAT2, TEST_MEM_SIZE),
+ "Shared memory view mismatch");
+ VM_STAGE_PROCESSED(PSPAHCT_GUEST_SHARED_MEM_UPDATED);
+ break;
+ }
+ case PSPAHCT_GUEST_PRIVATE_MEM_UPDATED2: {
+ /* verify data to be same as what guest wrote earlier */
+ TEST_ASSERT(do_mem_op(VERIFY_PAT, shared_mem,
+ TEST_MEM_DATA_PAT2, TEST_MEM_SIZE),
+ "Shared memory view mismatch");
+ VM_STAGE_PROCESSED(PSPAHCT_GUEST_PRIVATE_MEM_UPDATED2);
+ break;
+ }
+ default:
+ printf("Unhandled VM stage %ld\n", stage);
+ return false;
+ }
+
+ return true;
+}
+
+static void pspahct_guest_code(void)
+{
+ void *test_mem = (void *)TEST_MEM_GPA;
+ int ret;
+
+ GUEST_SYNC(PSPAHCT_GUEST_STARTED);
+
+ /* Mark the GPA range to be treated as always accessed privately */
+ ret = kvm_hypercall(KVM_HC_MAP_GPA_RANGE, TEST_MEM_GPA,
+ TEST_MEM_SIZE >> MIN_PAGE_SHIFT,
+ KVM_MARK_GPA_RANGE_ENC_ACCESS, 0);
+ GUEST_ASSERT_1(ret == 0, ret);
+ GUEST_ASSERT(do_mem_op(SET_PAT, test_mem,
+ TEST_MEM_DATA_PAT2, TEST_MEM_SIZE));
+
+ GUEST_SYNC(PSPAHCT_GUEST_PRIVATE_MEM_UPDATED);
+ GUEST_ASSERT(do_mem_op(VERIFY_PAT, test_mem,
+ TEST_MEM_DATA_PAT2, TEST_MEM_SIZE));
+
+ /* Map the GPA range to be treated as shared */
+ ret = kvm_hypercall(KVM_HC_MAP_GPA_RANGE, TEST_MEM_GPA,
+ TEST_MEM_SIZE >> MIN_PAGE_SHIFT,
+ KVM_MAP_GPA_RANGE_DECRYPTED | KVM_MAP_GPA_RANGE_PAGE_SZ_4K, 0);
+ GUEST_ASSERT_1(ret == 0, ret);
+
+ /* Mark the GPA range to be treated as always accessed via shared
+ * access
+ */
+ ret = kvm_hypercall(KVM_HC_MAP_GPA_RANGE, 0, 0,
+ KVM_MARK_GPA_RANGE_ENC_ACCESS, 0);
+ GUEST_ASSERT_1(ret == 0, ret);
+
+ GUEST_ASSERT(do_mem_op(VERIFY_PAT, test_mem,
+ TEST_MEM_DATA_PAT1, TEST_MEM_SIZE));
+ GUEST_ASSERT(do_mem_op(SET_PAT, test_mem,
+ TEST_MEM_DATA_PAT2, TEST_MEM_SIZE));
+ GUEST_SYNC(PSPAHCT_GUEST_SHARED_MEM_UPDATED);
+
+ GUEST_ASSERT(do_mem_op(VERIFY_PAT, test_mem,
+ TEST_MEM_DATA_PAT2, TEST_MEM_SIZE));
+
+ /* Map the GPA range to be treated as private */
+ ret = kvm_hypercall(KVM_HC_MAP_GPA_RANGE, TEST_MEM_GPA,
+ TEST_MEM_SIZE >> MIN_PAGE_SHIFT,
+ KVM_MAP_GPA_RANGE_ENCRYPTED | KVM_MAP_GPA_RANGE_PAGE_SZ_4K, 0);
+ GUEST_ASSERT_1(ret == 0, ret);
+
+ /* Mark the GPA range to be treated as always accessed via private
+ * access
+ */
+ ret = kvm_hypercall(KVM_HC_MAP_GPA_RANGE, TEST_MEM_GPA,
+ TEST_MEM_SIZE >> MIN_PAGE_SHIFT,
+ KVM_MARK_GPA_RANGE_ENC_ACCESS, 0);
+ GUEST_ASSERT_1(ret == 0, ret);
+
+ GUEST_ASSERT(do_mem_op(SET_PAT, test_mem,
+ TEST_MEM_DATA_PAT1, TEST_MEM_SIZE));
+ GUEST_SYNC(PSPAHCT_GUEST_PRIVATE_MEM_UPDATED2);
+ GUEST_ASSERT(do_mem_op(VERIFY_PAT, test_mem,
+ TEST_MEM_DATA_PAT1, TEST_MEM_SIZE));
+ GUEST_DONE();
+}
+
static struct test_run_helper priv_memfd_testsuite[] = {
[PMPAT_ID] = {
.test_desc = PMPAT_DESC,
@@ -605,6 +748,11 @@ static struct test_run_helper priv_memfd_testsuite[] = {
.vmst_handler = spat_handle_vm_stage,
.guest_fn = spat_guest_code,
},
+ [PSPAHCT_ID] = {
+ .test_desc = PSPAHCT_DESC,
+ .vmst_handler = pspahct_handle_vm_stage,
+ .guest_fn = pspahct_guest_code,
+ },
};

static void handle_vm_exit_hypercall(struct kvm_run *run,
--
2.36.0.550.gb090851708-goog