This patch test the issue fixed by KVM commit "KVM: nVMX: Fix loss of
pending event before entering L2". The test aim to verify that a pending
interrupt while interrupts are disabled is dispatched when we enter into
VMX guest instead of being lost.
The test configures VMCS to intercept external-interrupts and then
queue an interrupt by disabling interrupts and issue a self-IPI.
At this point, we enter guest and we expect CPU to immediately exit
guest on external-interrupt. To complete the test, we then re-enable
interrupts, verify interrupt is dispatched and re-enter guest to verify
it completes execution.
Reviewed-by: Nikita Leshchenko <nikita.leshchenko@xxxxxxxxxx>
Reviewed-by: Darren Kenny <darren.kenny@xxxxxxxxxx>
Signed-off-by: Liran Alon <liran.alon@xxxxxxxxxx>
---
x86/unittests.cfg | 6 ++++++
x86/vmx_tests.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 54 insertions(+)
diff --git a/x86/unittests.cfg b/x86/unittests.cfg
index 9d3931921440..8d1c7db1cf6f 100644
--- a/x86/unittests.cfg
+++ b/x86/unittests.cfg
@@ -554,6 +554,12 @@ extra_params = -cpu host,+vmx -m 2560 -append vmx_cr_load_test
arch = x86_64
groups = vmx
+[vmx_pending_event_test]
+file = vmx.flat
+extra_params = -cpu host,+vmx -m 2560 -append vmx_pending_event_test
+arch = x86_64
+groups = vmx
+
[vmx_eoi_bitmap_ioapic_scan]
file = vmx.flat
smp = 2
diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index 7a41732d058a..21b474db012b 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -4457,6 +4457,53 @@ static void vmx_cr_load_test(void)
TEST_ASSERT(!write_cr4_checking(cr4 & ~X86_CR4_PCIDE));
}
+bool vmx_pending_event_ipi_fired;
+static void vmx_pending_event_ipi_isr(isr_regs_t *regs)
+{
+ vmx_pending_event_ipi_fired = true;
+ eoi();
+}
+
+bool vmx_pending_event_guest_run;
+static void vmx_pending_event_guest(void)
+{
+ vmx_pending_event_guest_run = true;
+}
+
+static void vmx_pending_event_test(void)
+{
+ int ipi_vector = 0xf1;
+
+ vmx_pending_event_ipi_fired = false;
+ handle_irq(ipi_vector, vmx_pending_event_ipi_isr);
+
+ vmx_pending_event_guest_run = false;
+ test_set_guest(vmx_pending_event_guest);
+
+ vmcs_set_bits(PIN_CONTROLS, PIN_EXTINT);
+
+ irq_disable();
+ apic_icr_write(APIC_DEST_SELF | APIC_DEST_PHYSICAL |
+ APIC_DM_FIXED | ipi_vector,
+ 0);
+
+ enter_guest();
+
+ assert_exit_reason(VMX_EXTINT);
+ report("Guest did not run before host received IPI",
+ !vmx_pending_event_guest_run);
+
+ irq_enable();
+ asm volatile ("nop");
+ irq_disable();
+ report("Got pending interrupt after IRQ enabled",
+ vmx_pending_event_ipi_fired);
+
+ enter_guest();
+ report("Guest finished running when no interrupt",
+ vmx_pending_event_guest_run);
+}
+
static bool cpu_has_apicv(void)
{
return ((ctrl_cpu_rev[1].clr & CPU_APIC_REG_VIRT) &&
@@ -5016,6 +5063,7 @@ struct vmx_test vmx_tests[] = {
TEST(vmx_vmcs_shadow_test),
/* Regression tests */
TEST(vmx_cr_load_test),
+ TEST(vmx_pending_event_test),
/* EPT access tests. */
TEST(ept_access_test_not_present),
TEST(ept_access_test_read_only),
--
2.16.1
