[PATCH v3 09/13] KVM: selftests: Always assert that vmptrld() succeeds

[Sean Christopherson <seanjc@google.com>]

Assert that vmptrld() succeeds instead of forcing all callers to do the
same, and opportunistically provide a macro to print (hopefully) useful
information on VMX instruction failures.

Leave load_vmcs() as-is for the moment to minimize the amount of churn
since the vmptrld() changes aren't completely trivial.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 tools/testing/selftests/kvm/include/x86/vmx.h | 23 +++++++++----------
 tools/testing/selftests/kvm/lib/x86/vmx.c     |  3 +--
 tools/testing/selftests/kvm/x86/state_test.c  |  6 ++---
 3 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86/vmx.h b/tools/testing/selftests/kvm/include/x86/vmx.h
index cf37a03a93b9..8f004b946826 100644
--- a/tools/testing/selftests/kvm/include/x86/vmx.h
+++ b/tools/testing/selftests/kvm/include/x86/vmx.h
@@ -309,6 +309,10 @@ struct vmx_msr_entry {
 
 #include "evmcs.h"
 
+#define GUEST_ASSERT_VMX_INSN_SUCCEEDED(insn, __r, __pa)		\
+	__GUEST_ASSERT(!__r, __stringify(insn) "[0x%lx] hit %s",	\
+		       __pa, __r < 0 ? "VM-Fail" : ex_str(__r))
+
 static inline void vmxon(u64 phys)
 {
 	u8 ret;
@@ -338,18 +342,6 @@ static inline void vmclear(u64 vmcs_pa)
 	__GUEST_ASSERT(!ret, "vmclear [0x%lx] failed\n", vmcs_pa);
 }
 
-static inline int vmptrld(u64 vmcs_pa)
-{
-	u8 ret;
-
-	__asm__ __volatile__ ("vmptrld %[pa]; setna %[ret]"
-		: [ret]"=rm"(ret)
-		: [pa]"m"(vmcs_pa)
-		: "cc", "memory");
-
-	return ret;
-}
-
 static inline int __vmptrld(u64 vmcs_pa)
 {
 	u64 error_code;
@@ -366,6 +358,13 @@ static inline int __vmptrld(u64 vmcs_pa)
 	return vector ? vector : failed ? -EINVAL : 0;
 }
 
+static inline void vmptrld(u64 vmcs_pa)
+{
+	int ret = __vmptrld(vmcs_pa);
+
+	GUEST_ASSERT_VMX_INSN_SUCCEEDED(vmptrld, ret, vmcs_pa);
+}
+
 static inline u64 vmptrst(void)
 {
 	u64 value = 0;
diff --git a/tools/testing/selftests/kvm/lib/x86/vmx.c b/tools/testing/selftests/kvm/lib/x86/vmx.c
index 57a8287de0d2..e65024b9ea0d 100644
--- a/tools/testing/selftests/kvm/lib/x86/vmx.c
+++ b/tools/testing/selftests/kvm/lib/x86/vmx.c
@@ -172,8 +172,7 @@ bool load_vmcs(struct vmx_pages *vmx)
 	*(u32 *)(vmx->vmcs) = vmcs_revision();
 	vmclear(vmx->vmcs_gpa);
 
-	if (vmptrld(vmx->vmcs_gpa))
-		return false;
+	vmptrld(vmx->vmcs_gpa);
 
 	/* Setup shadow VMCS, do not load it yet. */
 	*(u32 *)(vmx->shadow_vmcs) = vmcs_revision() | 0x80000000ul;
diff --git a/tools/testing/selftests/kvm/x86/state_test.c b/tools/testing/selftests/kvm/x86/state_test.c
index 203584fcaf62..a7786f478be0 100644
--- a/tools/testing/selftests/kvm/x86/state_test.c
+++ b/tools/testing/selftests/kvm/x86/state_test.c
@@ -108,7 +108,7 @@ static void vmx_l1_guest_code(struct vmx_pages *vmx_pages)
 	vmwrite(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_SHADOW_VMCS);
 	vmwrite(VMCS_LINK_POINTER, vmx_pages->shadow_vmcs_gpa);
 
-	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
+	vmptrld(vmx_pages->shadow_vmcs_gpa);
 	GUEST_ASSERT(vmlaunch());
 	GUEST_SYNC(8);
 	GUEST_ASSERT(vmlaunch());
@@ -118,11 +118,11 @@ static void vmx_l1_guest_code(struct vmx_pages *vmx_pages)
 	GUEST_SYNC(9);
 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
 
-	GUEST_ASSERT(!vmptrld(vmx_pages->vmcs_gpa));
+	vmptrld(vmx_pages->vmcs_gpa);
 	GUEST_ASSERT(!vmresume());
 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
 
-	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
+	vmptrld(vmx_pages->shadow_vmcs_gpa);
 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
 	GUEST_ASSERT(vmlaunch());
 	GUEST_ASSERT(vmresume());
-- 
2.55.0.887.g758fc8c411-goog