Ultimately, this test will be expanded to cover all of the "Checks on
VMX Controls" described in the Intel SDM, volume 3, section
26.2.1. For now, it just checks I/O bitmap and MSR bitmap settings.
Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
---
x86/unittests.cfg | 6 +++
x86/vmx_tests.c | 154 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 160 insertions(+)
diff --git a/x86/unittests.cfg b/x86/unittests.cfg
index c9858159c657..419b135ca9d4 100644
--- a/x86/unittests.cfg
+++ b/x86/unittests.cfg
@@ -500,6 +500,12 @@ extra_params = -cpu host,+vmx -m 2048 -append invvpid_test_v2
arch = x86_64
groups = vmx
+[vmx_controls]
+file = vmx.flat
+extra_params = -cpu host,+vmx -m 2048 -append vmx_controls_test
+arch = x86_64
+groups = vmx
+
[debug]
file = debug.flat
arch = x86_64
diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index ffc913573fb4..9c806f00ec85 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -3133,6 +3133,158 @@ static void invvpid_test_v2(void)
invvpid_test_not_in_vmx_operation();
}
+/*
+ * Test for early VMLAUNCH failure. Returns true if VMLAUNCH makes it
+ * at least as far as the guest-state checks. Returns false if the
+ * VMLAUNCH fails early and execution falls through to the next
+ * instruction.
+ */
+static bool vmlaunch_succeeds(void)
+{
+ register uintptr_t rsp __asm__("%rsp");
+
+ /*
+ * Indirectly set VMX_INST_ERR to 12 ("VMREAD/VMWRITE from/to
+ * unsupported VMCS component"). The caller can then check
+ * to see if a failed VM-entry sets VMX_INST_ERR as expected.
+ */
+ vmcs_write(~0u, 0);
+
+ vmcs_write(HOST_RIP, (uintptr_t)&&success);
+ vmcs_write(HOST_RSP, rsp);
+ __asm__ __volatile__ goto ("vmlaunch" : : : "cc", "memory" : success);
+ return false;
+success:
+ TEST_ASSERT(vmcs_read(EXI_REASON) ==
+ (VMX_FAIL_STATE | VMX_ENTRY_FAILURE));
+ return true;
+}
+
+/*
+ * Try to launch the current VMCS.
+ */
+static void test_vmx_controls(bool controls_valid)
+{
+ bool success = vmlaunch_succeeds();
+ u32 vmx_inst_err;
+
+ report("vmlaunch %s", success == controls_valid,
+ controls_valid ? "succeeds" : "fails");
+ if (!controls_valid) {
+ vmx_inst_err = vmcs_read(VMX_INST_ERROR);
+ report("VMX inst error is %d (actual %d)",
+ vmx_inst_err == VMXERR_ENTRY_INVALID_CONTROL_FIELD,
+ VMXERR_ENTRY_INVALID_CONTROL_FIELD, vmx_inst_err);
+ }
+}
+
+/*
+ * Test a particular address setting for a physical page reference in
+ * the VMCS.
+ */
+static void test_vmcs_page_addr(const char *name,
+ enum Encoding encoding,
+ bool ignored,
+ u64 addr)
+{
+ report_prefix_pushf("%s = %lx", name, addr);
+ vmcs_write(encoding, addr);
+ test_vmx_controls(ignored || (IS_ALIGNED(addr, PAGE_SIZE) &&
+ addr < (1ul << cpuid_maxphyaddr())));
+ report_prefix_pop();
+}
+
+/*
+ * Test interesting values for a physical page reference in the VMCS.
+ */
+static void test_vmcs_page_values(const char *name,
+ enum Encoding encoding,
+ bool ignored)
+{
+ unsigned i;
+ u64 orig_val = vmcs_read(encoding);
+
+ for (i = 0; i < 64; i++)
+ test_vmcs_page_addr(name, encoding, ignored, 1ul << i);
+
+ test_vmcs_page_addr(name, encoding, ignored, PAGE_SIZE - 1);
+ test_vmcs_page_addr(name, encoding, ignored, PAGE_SIZE);
+ test_vmcs_page_addr(name, encoding, ignored,
+ (1ul << cpuid_maxphyaddr()) - PAGE_SIZE);
+ test_vmcs_page_addr(name, encoding, ignored, -1ul);
+
+ vmcs_write(encoding, orig_val);
+}
+
+/*
+ * Test a physical page reference in the VMCS, when the corresponding
+ * feature is enabled and when the corresponding feature is disabled.
+ */
+static void test_vmcs_page_reference(u32 control_bit, enum Encoding field,
+ const char *field_name,
+ const char *control_name)
+{
+ u32 primary = vmcs_read(CPU_EXEC_CTRL0);
+ u64 page_addr;
+
+ if (!(ctrl_cpu_rev[0].clr & control_bit))
+ return;
+
+ page_addr = vmcs_read(field);
+
+ report_prefix_pushf("%s enabled", control_name);
+ vmcs_write(CPU_EXEC_CTRL0, primary | control_bit);
+ test_vmcs_page_values(field_name, field, false);
+ report_prefix_pop();
+
+ report_prefix_pushf("%s disabled", control_name);
+ vmcs_write(CPU_EXEC_CTRL0, primary & ~control_bit);
+ test_vmcs_page_values(field_name, field, true);
+ report_prefix_pop();
+
+ vmcs_write(field, page_addr);
+ vmcs_write(CPU_EXEC_CTRL0, primary);
+}
+
+/*
+ * If the "use I/O bitmaps" VM-execution control is 1, bits 11:0 of
+ * each I/O-bitmap address must be 0. Neither address should set any
+ * bits beyond the processor's physical-address width.
+ * [Intel SDM]
+ */
+static void test_io_bitmaps(void)
+{
+ test_vmcs_page_reference(CPU_IO_BITMAP, IO_BITMAP_A,
+ "I/O bitmap A", "Use I/O bitmaps");
+ test_vmcs_page_reference(CPU_IO_BITMAP, IO_BITMAP_B,
+ "I/O bitmap B", "Use I/O bitmaps");
+}
+
+/*
+ * If the "use MSR bitmaps" VM-execution control is 1, bits 11:0 of
+ * the MSR-bitmap address must be 0. The address should not set any
+ * bits beyond the processor's physical-address width.
+ * [Intel SDM]
+ */
+static void test_msr_bitmap(void)
+{
+ test_vmcs_page_reference(CPU_MSR_BITMAP, MSR_BITMAP,
+ "MSR bitmap", "Use MSR bitmaps");
+}
+
+static void vmx_controls_test(void)
+{
+ /*
+ * Bit 1 of the guest's RFLAGS must be 1, or VM-entry will
+ * fail due to invalid guest state, should we make it that
+ * far.
+ */
+ vmcs_write(GUEST_RFLAGS, 0);
+
+ test_io_bitmaps();
+ test_msr_bitmap();
+}
+
#define TEST(name) { #name, .v2 = name }
/* name/init/guest_main/exit_handler/syscall_handler/guest_regs */
@@ -3196,5 +3348,7 @@ struct vmx_test vmx_tests[] = {
TEST(ept_access_test_force_2m_page),
/* Opcode tests. */
TEST(invvpid_test_v2),
+ /* VM-entry tests */
+ TEST(vmx_controls_test),
{ NULL, NULL, NULL, NULL, NULL, {0} },
};
--
2.13.2.725.g09c95d1e9-goog
