[kvm-unit-tests PATCH] x86: VMX: test MTF VM-exit event injection

[Oliver Upton <oupton@google.com>]

SDM 26.6.2 describes how the VM-entry interruption-information field
may be configured to inject an MTF VM-exit upon VM-entry. Ensure that an
MTF VM-exit occurs when the VM-entry interruption-information field is
configured appropriately by the host.

Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
---
 Parent commit: b16df9e ("arch-run: Add reserved variables to the default environ")
 x86/vmx_tests.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index 1f97fe3..a91715f 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -4964,6 +4964,7 @@ static void test_vmx_preemption_timer(void)
 extern unsigned char test_mtf1;
 extern unsigned char test_mtf2;
 extern unsigned char test_mtf3;
+extern unsigned char test_mtf4;
 
 static void test_mtf_guest(void)
 {
@@ -4992,7 +4993,10 @@ static void test_mtf_guest(void)
 	      * documented, don't rely on assemblers enumerating the
 	      * instruction. Resort to hand assembly.
 	      */
-	     ".byte 0xf1;\n\t");
+	     ".byte 0xf1;\n\t"
+	     "vmcall;\n\t"
+	     "test_mtf4:\n\t"
+	     "mov $0, %eax;\n\t");
 }
 
 static void test_mtf_gp_handler(struct ex_regs *regs)
@@ -5037,7 +5041,7 @@ static void report_mtf(const char *insn_name, unsigned long exp_rip)
 	unsigned long rip = vmcs_read(GUEST_RIP);
 
 	assert_exit_reason(VMX_MTF);
-	report(rip == exp_rip, "MTF VM-exit after %s instruction. RIP: 0x%lx (expected 0x%lx)",
+	report(rip == exp_rip, "MTF VM-exit after %s. RIP: 0x%lx (expected 0x%lx)",
 	       insn_name, rip, exp_rip);
 }
 
@@ -5114,7 +5118,12 @@ static void vmx_mtf_test(void)
 	disable_mtf();
 
 	enter_guest();
+	skip_exit_vmcall();
 	handle_exception(DB_VECTOR, old_db);
+	vmcs_write(ENT_INTR_INFO, INTR_INFO_VALID_MASK | INTR_TYPE_OTHER_EVENT);
+	enter_guest();
+	report_mtf("injected MTF", (unsigned long) &test_mtf4);
+	enter_guest();
 }
 
 /*
-- 
2.26.0.110.g2183baf09c-goog