[kvm-unit-test,2/2] nVMX x86: "virtualize APIC accesses" must be unset if "virtualize x2APIC" is set

Commit Message

Krish Sadhukhan June 29, 2018, 7:07 p.m. UTC

According to section "Checks on VMX Controls" in Intel SDM vol 3C,

the following check needs to be enforced on vmentry of L2 guests:

     If the "virtualize x2APIC mode" VM-execution control is 1, the
     "virtualize APIC accesses" VM-execution control must be 0.

This unit-test validates the above vmentry check.

Signed-off-by: Krish Sadhukhan <[e-mail]>
Reviewed-by: Jim Mattson <[e-mail]>
Reviewed-by: Karl Heubaum <[e-mail]>
---
  x86/vmx_tests.c | 40 ++++++++++++++++++++++++++++++++++++++++
  1 file changed, 40 insertions(+)

Patch

diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index 64be48f..e549362 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -3586,6 +3586,11 @@  static void test_apic_access_addr(void)
   * 	- virtualize x2APIC mode
   *	- APIC-register virtualization
   *	- virtual-interrupt delivery
+ *    [Intel SDM]
+ *
+ * 2. If the "virtualize x2APIC mode" VM-execution control is 1, the
+ *    "virtualize APIC accesses" VM-execution control must be 0.
+ *    [Intel SDM]
   */
  static void test_apic_virtual_ctls(void)
  {
@@ -3597,6 +3602,9 @@  static void test_apic_virtual_ctls(void)
  	bool cpu_has_apic_reg_virt = 0;
  	bool cpu_has_vintd = 0;
  
+	/*
+	 * First test
+	 */
  	if (!((ctrl_cpu_rev[0].clr & (CPU_SECONDARY | CPU_TPR_SHADOW)) ==
  	    (CPU_SECONDARY | CPU_TPR_SHADOW)))
  		return;
@@ -3674,6 +3682,38 @@  static void test_apic_virtual_ctls(void)
  		report_prefix_pop();
  	}
  
+	/*
+	 * Second test
+	 */
+	u32 apic_virt_ctls = (CPU_VIRT_X2APIC | CPU_VIRT_APIC_ACCESSES);
+
+	primary = saved_primary;
+	secondary = saved_secondary;
+	if (!((ctrl_cpu_rev[1].clr & apic_virt_ctls) == apic_virt_ctls))
+		return;
+
+	vmcs_write(CPU_EXEC_CTRL0, primary | CPU_SECONDARY);
+	secondary &= ~CPU_VIRT_APIC_ACCESSES;
+	vmcs_write(CPU_EXEC_CTRL1, secondary & ~CPU_VIRT_X2APIC);
+	report_prefix_pushf("Virtualize x2APIC mode disabled; virtualize APIC access disabled");
+	test_vmx_controls(true, false);
+	report_prefix_pop();
+
+	vmcs_write(CPU_EXEC_CTRL1, secondary | CPU_VIRT_APIC_ACCESSES);
+	report_prefix_pushf("Virtualize x2APIC mode disabled; virtualize APIC access enabled");
+	test_vmx_controls(true, false);
+	report_prefix_pop();
+
+	vmcs_write(CPU_EXEC_CTRL1, secondary | CPU_VIRT_X2APIC);
+	report_prefix_pushf("Virtualize x2APIC mode enabled; virtualize APIC access enabled");
+	test_vmx_controls(false, false);
+	report_prefix_pop();
+
+	vmcs_write(CPU_EXEC_CTRL1, secondary & ~CPU_VIRT_APIC_ACCESSES);
+	report_prefix_pushf("Virtualize x2APIC mode enabled; virtualize APIC access disabled");
+	test_vmx_controls(true, false);
+	report_prefix_pop();
+
  	vmcs_write(CPU_EXEC_CTRL0, saved_primary);
  	vmcs_write(CPU_EXEC_CTRL1, saved_secondary);
  }