Add vmx test to verify the functionality introduced by KVM commit:
4b9852f4f389 ("KVM: x86: Fix INIT signal handling in various CPU states").
The test verifies the following functionality:
1) An INIT signal received when CPU is in VMX operation
is blocked until it exits VMX operation.
2) If there is an INIT signal pending when CPU is in
VMX non-root mode, it result in VMExit with (reason == 3).
3) Exit from VMX non-root mode on VMExit do not clear
pending INIT signal in LAPIC.
4) When CPU exits VMX operation, pending INIT signal in
LAPIC is processed.
Note: The test is excluded from the "vmx" test-suite as
it ruins the execution environment of CPU1 because
during the test it process an INIT signal.
Reviewed-by: Nikita Leshenko <nikita.leshchenko@xxxxxxxxxx>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
Signed-off-by: Liran Alon <liran.alon@xxxxxxxxxx>
---
x86/unittests.cfg | 10 +++-
x86/vmx_tests.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 154 insertions(+), 1 deletion(-)
diff --git a/x86/unittests.cfg b/x86/unittests.cfg
index 694ee3d42f3a..8156256146c3 100644
--- a/x86/unittests.cfg
+++ b/x86/unittests.cfg
@@ -227,7 +227,7 @@ extra_params = -cpu qemu64,+umip
[vmx]
file = vmx.flat
-extra_params = -cpu host,+vmx -append "-exit_monitor_from_l2_test -ept_access* -vmx_smp* -vmx_vmcs_shadow_test"
+extra_params = -cpu host,+vmx -append "-exit_monitor_from_l2_test -ept_access* -vmx_smp* -vmx_vmcs_shadow_test -vmx_init_signal_test"
arch = x86_64
groups = vmx
@@ -265,6 +265,14 @@ extra_params = -cpu host,+vmx -m 2048 -append vmx_apic_passthrough_thread_test
arch = x86_64
groups = vmx
+[vmx_init_signal_test]
+file = vmx.flat
+smp = 2
+extra_params = -cpu host,+vmx -m 2048 -append vmx_init_signal_test
+arch = x86_64
+groups = vmx
+timeout = 10
+
[vmx_vmcs_shadow_test]
file = vmx.flat
extra_params = -cpu host,+vmx -append vmx_vmcs_shadow_test
diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index 096640a56891..962990e30d33 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -8219,6 +8219,150 @@ static void vmx_apic_passthrough_thread_test(void)
vmx_apic_passthrough(true);
}
+static u64 init_signal_test_exit_reason;
+static bool init_signal_test_thread_continued;
+
+static void init_signal_test_thread(void *data)
+{
+ struct vmcs *test_vmcs = data;
+
+ /* Enter VMX operation (i.e. exec VMXON) */
+ u64 *ap_vmxon_region = alloc_page();
+ enable_vmx();
+ init_vmx(ap_vmxon_region);
+ _vmx_on(ap_vmxon_region);
+
+ /* Signal CPU have entered VMX operation */
+ vmx_set_test_stage(1);
+
+ /* Wait for BSP CPU to send INIT signal */
+ while (vmx_get_test_stage() != 2)
+ ;
+
+ /*
+ * Signal that we continue as usual as INIT signal
+ * should be blocked while CPU is in VMX operation
+ */
+ vmx_set_test_stage(3);
+
+ /* Wait for signal to enter VMX non-root mode */
+ while (vmx_get_test_stage() != 4)
+ ;
+
+ /* Enter VMX non-root mode */
+ test_set_guest(v2_null_test_guest);
+ make_vmcs_current(test_vmcs);
+ enter_guest();
+ /* Save exit reason for BSP CPU to compare to expected result */
+ init_signal_test_exit_reason = vmcs_read(EXI_REASON);
+ /* VMCLEAR test-vmcs so it could be loaded by BSP CPU */
+ vmcs_clear(test_vmcs);
+ launched = false;
+ /* Signal that CPU exited to VMX root mode */
+ vmx_set_test_stage(5);
+
+ /* Wait for signal to exit VMX operation */
+ while (vmx_get_test_stage() != 6)
+ ;
+
+ /* Exit VMX operation (i.e. exec VMXOFF) */
+ vmx_off();
+
+ /*
+ * Exiting VMX operation should result in latched
+ * INIT signal being processed. Therefore, we should
+ * never reach the below code. Thus, signal to BSP
+ * CPU if we have reached here so it is able to
+ * report an issue if it happens.
+ */
+ init_signal_test_thread_continued = true;
+}
+
+#define INIT_SIGNAL_TEST_DELAY 100000000ULL
+
+static void vmx_init_signal_test(void)
+{
+ struct vmcs *test_vmcs;
+
+ if (cpu_count() < 2) {
+ report_skip(__func__);
+ return;
+ }
+
+ /* VMCLEAR test-vmcs so it could be loaded by other CPU */
+ vmcs_save(&test_vmcs);
+ vmcs_clear(test_vmcs);
+
+ vmx_set_test_stage(0);
+ on_cpu_async(1, init_signal_test_thread, test_vmcs);
+
+ /* Wait for other CPU to enter VMX operation */
+ while (vmx_get_test_stage() != 1)
+ ;
+
+ /* Send INIT signal to other CPU */
+ apic_icr_write(APIC_DEST_PHYSICAL | APIC_DM_INIT | APIC_INT_ASSERT,
+ id_map[1]);
+ /* Signal other CPU we have sent INIT signal */
+ vmx_set_test_stage(2);
+
+ /*
+ * Wait reasonable amount of time for INIT signal to
+ * be received on other CPU and verify that other CPU
+ * have proceed as usual to next test stage as INIT
+ * signal should be blocked while other CPU in
+ * VMX operation
+ */
+ delay(INIT_SIGNAL_TEST_DELAY);
+ report("INIT signal blocked when CPU in VMX operation",
+ vmx_get_test_stage() == 3);
+ /* No point to continue if we failed at this point */
+ if (vmx_get_test_stage() != 3)
+ return;
+
+ /* Signal other CPU to enter VMX non-root mode */
+ init_signal_test_exit_reason = -1ull;
+ vmx_set_test_stage(4);
+ /*
+ * Wait reasonable amont of time for other CPU
+ * to exit to VMX root mode
+ */
+ delay(INIT_SIGNAL_TEST_DELAY);
+ if (vmx_get_test_stage() != 5) {
+ report("Pending INIT signal haven't resulted in VMX exit", false);
+ return;
+ }
+ report("INIT signal during VMX non-root mode result in exit-reason %s (%lu)",
+ init_signal_test_exit_reason == VMX_INIT,
+ exit_reason_description(init_signal_test_exit_reason),
+ init_signal_test_exit_reason);
+
+ /* Run guest to completion */
+ make_vmcs_current(test_vmcs);
+ enter_guest();
+
+ /* Signal other CPU to exit VMX operation */
+ init_signal_test_thread_continued = false;
+ vmx_set_test_stage(6);
+
+ /*
+ * Wait reasonable amount of time for other CPU
+ * to run after INIT signal was processed
+ */
+ delay(INIT_SIGNAL_TEST_DELAY);
+ report("INIT signal processed after exit VMX operation",
+ !init_signal_test_thread_continued);
+
+ /*
+ * TODO: Send SIPI to other CPU to sipi_entry (See x86/cstart64.S)
+ * to re-init it to kvm-unit-tests standard environment.
+ * Somehow (?) verify that SIPI was indeed received.
+ */
+
+ /* Report success */
+ report(__func__, 1);
+}
+
enum vmcs_access {
ACCESS_VMREAD,
ACCESS_VMWRITE,
@@ -8629,6 +8773,7 @@ struct vmx_test vmx_tests[] = {
/* APIC pass-through tests */
TEST(vmx_apic_passthrough_test),
TEST(vmx_apic_passthrough_thread_test),
+ TEST(vmx_init_signal_test),
/* VMCS Shadowing tests */
TEST(vmx_vmcs_shadow_test),
/* Regression tests */
--
2.20.1
