[kvm-unit-tests,2/8] nVMX: Refactor VM-Entry "failure" struct into "result"
diff mbox series

Message ID 20200312232745.884-3-sean.j.christopherson@intel.com
State New
Headers show
Series
  • nVMX: Clean up __enter_guest() and co.
Related show

Commit Message

Sean Christopherson March 12, 2020, 11:27 p.m. UTC
Rename "struct vmentry_failure" to "struct vmentry_result" and add the
full VM-Exit reason to the result.  Implement exit_reason as a union so
that tests can easily pull out the parts of interest, e.g. basic exit
reason, whether VM-Entry failed, etc...

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
 x86/vmx.c       | 128 ++++++++++++++++++++++++++----------------------
 x86/vmx.h       |  39 ++++++++++++---
 x86/vmx_tests.c |  24 ++++-----
 3 files changed, 112 insertions(+), 79 deletions(-)

Comments

Krish Sadhukhan March 18, 2020, 11:40 p.m. UTC | #1
On 3/12/20 4:27 PM, Sean Christopherson wrote:
> Rename "struct vmentry_failure" to "struct vmentry_result" and add the
> full VM-Exit reason to the result.  Implement exit_reason as a union so
> that tests can easily pull out the parts of interest, e.g. basic exit
> reason, whether VM-Entry failed, etc...
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> ---
>   x86/vmx.c       | 128 ++++++++++++++++++++++++++----------------------
>   x86/vmx.h       |  39 ++++++++++++---
>   x86/vmx_tests.c |  24 ++++-----
>   3 files changed, 112 insertions(+), 79 deletions(-)
>
> diff --git a/x86/vmx.c b/x86/vmx.c
> index 99c3791..da17807 100644
> --- a/x86/vmx.c
> +++ b/x86/vmx.c
> @@ -607,11 +607,14 @@ void print_vmexit_info()
>   		regs.r12, regs.r13, regs.r14, regs.r15);
>   }
>   
> -void
> -print_vmentry_failure_info(struct vmentry_failure *failure) {
> -	if (failure->early) {
> -		printf("Early %s failure: ", failure->instr);
> -		switch (failure->flags & VMX_ENTRY_FLAGS) {
> +void print_vmentry_failure_info(struct vmentry_result *result)
> +{
> +	if (result->entered)
> +		return;
> +
> +	if (result->vm_fail) {
> +		printf("VM-Fail on %s: ", result->instr);
> +		switch (result->flags & VMX_ENTRY_FLAGS) {
>   		case X86_EFLAGS_CF:
>   			printf("current-VMCS pointer is not valid.\n");
>   			break;
> @@ -620,16 +623,15 @@ print_vmentry_failure_info(struct vmentry_failure *failure) {
>   			       vmcs_read(VMX_INST_ERROR));
>   			break;
>   		default:
> -			printf("unexpected flags %lx!\n", failure->flags);
> +			printf("unexpected flags %lx!\n", result->flags);
>   		}
>   	} else {
> -		u64 reason = vmcs_read(EXI_REASON);
>   		u64 qual = vmcs_read(EXI_QUALIFICATION);
>   
> -		printf("Non-early %s failure (reason=%#lx, qual=%#lx): ",
> -			failure->instr, reason, qual);
> +		printf("VM-Exit failure on %s (reason=%#x, qual=%#lx): ",
> +			result->instr, result->exit_reason.full, qual);
>   
> -		switch (reason & 0xff) {
> +		switch (result->exit_reason.basic) {
>   		case VMX_FAIL_STATE:
>   			printf("invalid guest state\n");
>   			break;
> @@ -640,14 +642,14 @@ print_vmentry_failure_info(struct vmentry_failure *failure) {
>   			printf("machine-check event\n");
>   			break;
>   		default:
> -			printf("unexpected basic exit reason %ld\n",
> -			       reason & 0xff);
> +			printf("unexpected basic exit reason %u\n",
> +			  result->exit_reason.basic);
>   		}
>   
> -		if (!(reason & VMX_ENTRY_FAILURE))
> +		if (!result->exit_reason.failed_vmentry)
>   			printf("\tVMX_ENTRY_FAILURE BIT NOT SET!\n");
>   
> -		if (reason & 0x7fff0000)
> +		if (result->exit_reason.full & 0x7fff0000)
>   			printf("\tRESERVED BITS SET!\n");
>   	}
>   }
> @@ -1632,12 +1634,12 @@ static int exit_handler(void)
>   }
>   
>   /*
> - * Tries to enter the guest. Returns true if entry succeeded. Otherwise,
> - * populates @failure.
> + * Tries to enter the guest, populates @result with VM-Fail, VM-Exit, entered,
> + * etc...
>    */
> -static void vmx_enter_guest(struct vmentry_failure *failure)
> +static void vmx_enter_guest(struct vmentry_result *result)
>   {
> -	failure->early = 0;
> +	memset(result, 0, sizeof(*result));
>   
>   	in_guest = 1;
>   	asm volatile (
> @@ -1654,35 +1656,35 @@ static void vmx_enter_guest(struct vmentry_failure *failure)
>   		SAVE_GPR_C
>   		"pushf\n\t"
>   		"pop %%rdi\n\t"
> -		"mov %%rdi, %[failure_flags]\n\t"
> -		"movl $1, %[failure_early]\n\t"
> +		"mov %%rdi, %[vm_fail_flags]\n\t"
> +		"movl $1, %[vm_fail]\n\t"
>   		"jmp 3f\n\t"
>   		"vmx_return:\n\t"
>   		SAVE_GPR_C
>   		"3: \n\t"
> -		: [failure_early]"+m"(failure->early),
> -		  [failure_flags]"=m"(failure->flags)
> +		: [vm_fail]"+m"(result->vm_fail),
> +		  [vm_fail_flags]"=m"(result->flags)
>   		: [launched]"m"(launched), [HOST_RSP]"i"(HOST_RSP)
>   		: "rdi", "memory", "cc"
>   	);
>   	in_guest = 0;
>   
> -	failure->vmlaunch = !launched;
> -	failure->instr = launched ? "vmresume" : "vmlaunch";
> +	result->vmlaunch = !launched;
> +	result->instr = launched ? "vmresume" : "vmlaunch";
> +	result->exit_reason.full = result->vm_fail ? 0xdead :
> +						     vmcs_read(EXI_REASON);
> +	result->entered = !result->vm_fail &&
> +			  !result->exit_reason.failed_vmentry;
>   }
>   
>   static int vmx_run(void)
>   {
> +	struct vmentry_result result;
> +	u32 ret;
> +
>   	while (1) {
> -		u32 ret;
> -		bool entered;
> -		struct vmentry_failure failure;
> -
> -		vmx_enter_guest(&failure);
> -		entered = !failure.early &&
> -			  !(vmcs_read(EXI_REASON) & VMX_ENTRY_FAILURE);
> -
> -		if (entered) {
> +		vmx_enter_guest(&result);
> +		if (result.entered) {
>   			/*
>   			 * VMCS isn't in "launched" state if there's been any
>   			 * entry failure (early or otherwise).
> @@ -1690,7 +1692,7 @@ static int vmx_run(void)
>   			launched = 1;
>   			ret = exit_handler();
>   		} else if (current->entry_failure_handler) {
> -			ret = current->entry_failure_handler(failure);
> +			ret = current->entry_failure_handler(&result);
>   		} else {
>   			ret = VMX_TEST_EXIT;
>   		}
> @@ -1705,15 +1707,15 @@ static int vmx_run(void)
>   			break;
>   		default:
>   			printf("ERROR : Invalid %s_handler return val %d.\n",
> -			       entered ? "exit" : "entry_failure",
> +			       result.entered ? "exit" : "entry_failure",
>   			       ret);
>   			break;
>   		}
>   
> -		if (entered)
> +		if (result.entered)
>   			print_vmexit_info();
>   		else
> -			print_vmentry_failure_info(&failure);
> +			print_vmentry_failure_info(&result);
>   		abort();
>   	}
>   }
> @@ -1845,7 +1847,7 @@ static void check_for_guest_termination(void)
>    * Enters the guest (or launches it for the first time). Error to call once the
>    * guest has returned (i.e., run past the end of its guest() function).
>    */
> -static void __enter_guest(u8 abort_flag, struct vmentry_failure *failure)
> +static void __enter_guest(u8 abort_flag, struct vmentry_result *result)
>   {
>   	TEST_ASSERT_MSG(v2_guest_main,
>   			"Never called test_set_guest_func!");
> @@ -1853,24 +1855,32 @@ static void __enter_guest(u8 abort_flag, struct vmentry_failure *failure)
>   	TEST_ASSERT_MSG(!guest_finished,
>   			"Called enter_guest() after guest returned.");
>   
> -	vmx_enter_guest(failure);
> -	if ((abort_flag & ABORT_ON_EARLY_VMENTRY_FAIL && failure->early) ||
> -	    (abort_flag & ABORT_ON_INVALID_GUEST_STATE &&
> -	    vmcs_read(EXI_REASON) & VMX_ENTRY_FAILURE)) {
> +	vmx_enter_guest(result);
>   
> -		print_vmentry_failure_info(failure);
> -		abort();
> +	if (result->vm_fail) {
> +		if (abort_flag & ABORT_ON_EARLY_VMENTRY_FAIL)
> +			goto do_abort;
> +		return;
>   	}
> -
> -	if (!failure->early && !(vmcs_read(EXI_REASON) & VMX_ENTRY_FAILURE)) {
> -		launched = 1;
> -		check_for_guest_termination();
> +	if (result->exit_reason.failed_vmentry) {
> +		if ((abort_flag & ABORT_ON_INVALID_GUEST_STATE) ||
> +		    result->exit_reason.basic != VMX_FAIL_STATE)
> +			goto do_abort;
> +		return;
>   	}
> +
> +	launched = 1;
> +	check_for_guest_termination();
> +	return;
> +
> +do_abort:
> +	print_vmentry_failure_info(result);
> +	abort();
>   }
>   
>   void enter_guest_with_bad_controls(void)
>   {
> -	struct vmentry_failure failure = {0};
> +	struct vmentry_result result;
>   
>   	TEST_ASSERT_MSG(v2_guest_main,
>   			"Never called test_set_guest_func!");
> @@ -1878,10 +1888,10 @@ void enter_guest_with_bad_controls(void)
>   	TEST_ASSERT_MSG(!guest_finished,
>   			"Called enter_guest() after guest returned.");
>   
> -	__enter_guest(ABORT_ON_INVALID_GUEST_STATE, &failure);
> -	report(failure.early, "failure occurred early");
> -	report((failure.flags & VMX_ENTRY_FLAGS) == X86_EFLAGS_ZF,
> -               "FLAGS set correctly");
> +	__enter_guest(ABORT_ON_INVALID_GUEST_STATE, &result);
> +	report(result.vm_fail, "VM-Fail occurred as expected");
> +	report((result.flags & VMX_ENTRY_FLAGS) == X86_EFLAGS_ZF,
> +               "FLAGS set correctly on VM-Fail");
>   	report(vmcs_read(VMX_INST_ERROR) == VMXERR_ENTRY_INVALID_CONTROL_FIELD,
>   	       "VM-Inst Error # is %d (VM entry with invalid control field(s))",
>   	       VMXERR_ENTRY_INVALID_CONTROL_FIELD);
> @@ -1893,23 +1903,23 @@ void enter_guest_with_bad_controls(void)
>   	 * unexpectedly succeed, it's nice to check whether the guest has
>   	 * terminated, to reduce the number of error messages.
>   	 */
> -	if (!failure.early)
> +	if (!result.vm_fail)
>   		check_for_guest_termination();
>   }
>   
>   void enter_guest(void)
>   {
> -	struct vmentry_failure failure = {0};
> +	struct vmentry_result result;
>   
>   	__enter_guest(ABORT_ON_EARLY_VMENTRY_FAIL |
> -		      ABORT_ON_INVALID_GUEST_STATE, &failure);
> +		      ABORT_ON_INVALID_GUEST_STATE, &result);
>   }
>   
>   void enter_guest_with_invalid_guest_state(void)
>   {
> -	struct vmentry_failure failure = {0};
> +	struct vmentry_result result;
>   
> -	__enter_guest(ABORT_ON_EARLY_VMENTRY_FAIL, &failure);
> +	__enter_guest(ABORT_ON_EARLY_VMENTRY_FAIL, &result);
>   }
>   
>   extern struct vmx_test vmx_tests[];
> @@ -1924,6 +1934,8 @@ test_wanted(const char *name, const char *filters[], int filter_count)
>   	char *c;
>   	const char *n;
>   
> +	printf("filter = %s, test = %s\n", filters[0], name);
> +
>   	/* Replace spaces with underscores. */
>   	n = name;
>   	c = &clean_name[0];
> diff --git a/x86/vmx.h b/x86/vmx.h
> index 6adf091..c4a0fb4 100644
> --- a/x86/vmx.h
> +++ b/x86/vmx.h
> @@ -44,13 +44,38 @@ struct regs {
>   	u64 rflags;
>   };
>   
> -struct vmentry_failure {
> -	/* Did a vmlaunch or vmresume fail? */
> -	bool vmlaunch;
> +struct vmentry_result {
>   	/* Instruction mnemonic (for convenience). */
>   	const char *instr;
> -	/* Did the instruction return right away, or did we jump to HOST_RIP? */
> -	bool early;
> +	/* Did the test attempt vmlaunch or vmresume? */
> +	bool vmlaunch;
> +	/* Did the instruction VM-Fail? */
> +	bool vm_fail;


I still like the old name, "failure_early". To me, "vm_fail" and 
"failed_vmentry" sound similar and confusing.

The SDM calls this type of failure as "early failure" which is denoted 
by an (instruction) error number, in order to distinguish it from the 
failure that happens during guest state checking/loading. So, probably a 
better naming is "vm_early_failure" or "vm_fail_early". Or may be, 
"vm_instr_error" ?

> +	/* Did the VM-Entry fully enter the guest? */
> +	bool entered;
> +	/* VM-Exit reason, valid iff !vm_fail */
> +	union {
> +		struct {
> +			u32	basic			: 16;
> +			u32	reserved16		: 1;
> +			u32	reserved17		: 1;
> +			u32	reserved18		: 1;
> +			u32	reserved19		: 1;
> +			u32	reserved20		: 1;
> +			u32	reserved21		: 1;
> +			u32	reserved22		: 1;
> +			u32	reserved23		: 1;
> +			u32	reserved24		: 1;
> +			u32	reserved25		: 1;
> +			u32	reserved26		: 1;
> +			u32	enclave_mode		: 1;
> +			u32	smi_pending_mtf		: 1;
> +			u32	smi_from_vmx_root	: 1;
> +			u32	reserved30		: 1;
> +			u32	failed_vmentry		: 1;
> +		};
> +		u32 full;
> +	} exit_reason;
>   	/* Contents of [re]flags after failed entry. */
>   	unsigned long flags;
>   };
> @@ -62,7 +87,7 @@ struct vmx_test {
>   	int (*exit_handler)(void);
>   	void (*syscall_handler)(u64 syscall_no);
>   	struct regs guest_regs;
> -	int (*entry_failure_handler)(struct vmentry_failure *failure);
> +	int (*entry_failure_handler)(struct vmentry_result *result);
>   	struct vmcs *vmcs;
>   	int exits;
>   	/* Alternative test interface. */
> @@ -800,7 +825,7 @@ void init_vmx(u64 *vmxon_region);
>   
>   const char *exit_reason_description(u64 reason);
>   void print_vmexit_info(void);
> -void print_vmentry_failure_info(struct vmentry_failure *failure);
> +void print_vmentry_failure_info(struct vmentry_result *result);
>   void ept_sync(int type, u64 eptp);
>   void vpid_sync(int type, u16 vpid);
>   void install_ept_entry(unsigned long *pml4, int pte_level,
> diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
> index a7abd63..c4077b1 100644
> --- a/x86/vmx_tests.c
> +++ b/x86/vmx_tests.c
> @@ -1996,24 +1996,22 @@ static int msr_switch_exit_handler(void)
>   	return VMX_TEST_EXIT;
>   }
>   
> -static int msr_switch_entry_failure(struct vmentry_failure *failure)
> +static int msr_switch_entry_failure(struct vmentry_result *result)
>   {
> -	ulong reason;
> -
> -	if (failure->early) {
> -		printf("ERROR %s: early exit\n", __func__);
> +	if (result->vm_fail) {
> +		printf("ERROR %s: VM-Fail on %s\n", __func__, result->instr);
>   		return VMX_TEST_EXIT;
>   	}
>   
> -	reason = vmcs_read(EXI_REASON);
> -	if (reason == (VMX_ENTRY_FAILURE | VMX_FAIL_MSR) &&
> +	if (result->exit_reason.failed_vmentry &&
> +	    result->exit_reason.basic == VMX_FAIL_MSR &&
>   	    vmx_get_test_stage() == 3) {
>   		report(vmcs_read(EXI_QUALIFICATION) == 1,
>   		       "VM entry MSR load: try to load FS_BASE");
>   		return VMX_TEST_VMEXIT;
>   	}
> -	printf("ERROR %s: unexpected stage=%u or reason=%lu\n",
> -		__func__, vmx_get_test_stage(), reason);
> +	printf("ERROR %s: unexpected stage=%u or reason=%x\n",
> +		__func__, vmx_get_test_stage(), result->exit_reason.full);
>   	return VMX_TEST_EXIT;
>   }
>   
> @@ -9428,12 +9426,10 @@ static int invalid_msr_exit_handler(void)
>   	return VMX_TEST_EXIT;
>   }
>   
> -static int invalid_msr_entry_failure(struct vmentry_failure *failure)
> +static int invalid_msr_entry_failure(struct vmentry_result *result)
>   {
> -	ulong reason;
> -
> -	reason = vmcs_read(EXI_REASON);
> -	report(reason == (0x80000000u | VMX_FAIL_MSR), "Invalid MSR load");
> +	report(result->exit_reason.failed_vmentry &&
> +	       result->exit_reason.basic == VMX_FAIL_MSR, "Invalid MSR load");
>   	return VMX_TEST_VMEXIT;
>   }
>
Paolo Bonzini March 19, 2020, 9:56 a.m. UTC | #2
On 19/03/20 00:40, Krish Sadhukhan wrote:
>>
>> +    /* Did the test attempt vmlaunch or vmresume? */
>> +    bool vmlaunch;
>> +    /* Did the instruction VM-Fail? */
>> +    bool vm_fail;
> 
> 
> I still like the old name, "failure_early". To me, "vm_fail" and
> "failed_vmentry" sound similar and confusing.
> 
> The SDM calls this type of failure as "early failure" which is denoted
> by an (instruction) error number, in order to distinguish it from the
> failure that happens during guest state checking/loading. So, probably a
> better naming is "vm_early_failure" or "vm_fail_early". Or may be,
> "vm_instr_error" ?

This is actually what the SDM calls VMfailValid (we should never get to
VMfailInvalid in these tests), so vm_fail is appropriate.

failed_vmentry is what the SDM calls "VM-entry failure".

I agree that the names are similar and confusing, but there's some value
in keeping them close to the SDM.

Paolo

Patch
diff mbox series

diff --git a/x86/vmx.c b/x86/vmx.c
index 99c3791..da17807 100644
--- a/x86/vmx.c
+++ b/x86/vmx.c
@@ -607,11 +607,14 @@  void print_vmexit_info()
 		regs.r12, regs.r13, regs.r14, regs.r15);
 }
 
-void
-print_vmentry_failure_info(struct vmentry_failure *failure) {
-	if (failure->early) {
-		printf("Early %s failure: ", failure->instr);
-		switch (failure->flags & VMX_ENTRY_FLAGS) {
+void print_vmentry_failure_info(struct vmentry_result *result)
+{
+	if (result->entered)
+		return;
+
+	if (result->vm_fail) {
+		printf("VM-Fail on %s: ", result->instr);
+		switch (result->flags & VMX_ENTRY_FLAGS) {
 		case X86_EFLAGS_CF:
 			printf("current-VMCS pointer is not valid.\n");
 			break;
@@ -620,16 +623,15 @@  print_vmentry_failure_info(struct vmentry_failure *failure) {
 			       vmcs_read(VMX_INST_ERROR));
 			break;
 		default:
-			printf("unexpected flags %lx!\n", failure->flags);
+			printf("unexpected flags %lx!\n", result->flags);
 		}
 	} else {
-		u64 reason = vmcs_read(EXI_REASON);
 		u64 qual = vmcs_read(EXI_QUALIFICATION);
 
-		printf("Non-early %s failure (reason=%#lx, qual=%#lx): ",
-			failure->instr, reason, qual);
+		printf("VM-Exit failure on %s (reason=%#x, qual=%#lx): ",
+			result->instr, result->exit_reason.full, qual);
 
-		switch (reason & 0xff) {
+		switch (result->exit_reason.basic) {
 		case VMX_FAIL_STATE:
 			printf("invalid guest state\n");
 			break;
@@ -640,14 +642,14 @@  print_vmentry_failure_info(struct vmentry_failure *failure) {
 			printf("machine-check event\n");
 			break;
 		default:
-			printf("unexpected basic exit reason %ld\n",
-			       reason & 0xff);
+			printf("unexpected basic exit reason %u\n",
+			  result->exit_reason.basic);
 		}
 
-		if (!(reason & VMX_ENTRY_FAILURE))
+		if (!result->exit_reason.failed_vmentry)
 			printf("\tVMX_ENTRY_FAILURE BIT NOT SET!\n");
 
-		if (reason & 0x7fff0000)
+		if (result->exit_reason.full & 0x7fff0000)
 			printf("\tRESERVED BITS SET!\n");
 	}
 }
@@ -1632,12 +1634,12 @@  static int exit_handler(void)
 }
 
 /*
- * Tries to enter the guest. Returns true if entry succeeded. Otherwise,
- * populates @failure.
+ * Tries to enter the guest, populates @result with VM-Fail, VM-Exit, entered,
+ * etc...
  */
-static void vmx_enter_guest(struct vmentry_failure *failure)
+static void vmx_enter_guest(struct vmentry_result *result)
 {
-	failure->early = 0;
+	memset(result, 0, sizeof(*result));
 
 	in_guest = 1;
 	asm volatile (
@@ -1654,35 +1656,35 @@  static void vmx_enter_guest(struct vmentry_failure *failure)
 		SAVE_GPR_C
 		"pushf\n\t"
 		"pop %%rdi\n\t"
-		"mov %%rdi, %[failure_flags]\n\t"
-		"movl $1, %[failure_early]\n\t"
+		"mov %%rdi, %[vm_fail_flags]\n\t"
+		"movl $1, %[vm_fail]\n\t"
 		"jmp 3f\n\t"
 		"vmx_return:\n\t"
 		SAVE_GPR_C
 		"3: \n\t"
-		: [failure_early]"+m"(failure->early),
-		  [failure_flags]"=m"(failure->flags)
+		: [vm_fail]"+m"(result->vm_fail),
+		  [vm_fail_flags]"=m"(result->flags)
 		: [launched]"m"(launched), [HOST_RSP]"i"(HOST_RSP)
 		: "rdi", "memory", "cc"
 	);
 	in_guest = 0;
 
-	failure->vmlaunch = !launched;
-	failure->instr = launched ? "vmresume" : "vmlaunch";
+	result->vmlaunch = !launched;
+	result->instr = launched ? "vmresume" : "vmlaunch";
+	result->exit_reason.full = result->vm_fail ? 0xdead :
+						     vmcs_read(EXI_REASON);
+	result->entered = !result->vm_fail &&
+			  !result->exit_reason.failed_vmentry;
 }
 
 static int vmx_run(void)
 {
+	struct vmentry_result result;
+	u32 ret;
+
 	while (1) {
-		u32 ret;
-		bool entered;
-		struct vmentry_failure failure;
-
-		vmx_enter_guest(&failure);
-		entered = !failure.early &&
-			  !(vmcs_read(EXI_REASON) & VMX_ENTRY_FAILURE);
-
-		if (entered) {
+		vmx_enter_guest(&result);
+		if (result.entered) {
 			/*
 			 * VMCS isn't in "launched" state if there's been any
 			 * entry failure (early or otherwise).
@@ -1690,7 +1692,7 @@  static int vmx_run(void)
 			launched = 1;
 			ret = exit_handler();
 		} else if (current->entry_failure_handler) {
-			ret = current->entry_failure_handler(failure);
+			ret = current->entry_failure_handler(&result);
 		} else {
 			ret = VMX_TEST_EXIT;
 		}
@@ -1705,15 +1707,15 @@  static int vmx_run(void)
 			break;
 		default:
 			printf("ERROR : Invalid %s_handler return val %d.\n",
-			       entered ? "exit" : "entry_failure",
+			       result.entered ? "exit" : "entry_failure",
 			       ret);
 			break;
 		}
 
-		if (entered)
+		if (result.entered)
 			print_vmexit_info();
 		else
-			print_vmentry_failure_info(&failure);
+			print_vmentry_failure_info(&result);
 		abort();
 	}
 }
@@ -1845,7 +1847,7 @@  static void check_for_guest_termination(void)
  * Enters the guest (or launches it for the first time). Error to call once the
  * guest has returned (i.e., run past the end of its guest() function).
  */
-static void __enter_guest(u8 abort_flag, struct vmentry_failure *failure)
+static void __enter_guest(u8 abort_flag, struct vmentry_result *result)
 {
 	TEST_ASSERT_MSG(v2_guest_main,
 			"Never called test_set_guest_func!");
@@ -1853,24 +1855,32 @@  static void __enter_guest(u8 abort_flag, struct vmentry_failure *failure)
 	TEST_ASSERT_MSG(!guest_finished,
 			"Called enter_guest() after guest returned.");
 
-	vmx_enter_guest(failure);
-	if ((abort_flag & ABORT_ON_EARLY_VMENTRY_FAIL && failure->early) ||
-	    (abort_flag & ABORT_ON_INVALID_GUEST_STATE &&
-	    vmcs_read(EXI_REASON) & VMX_ENTRY_FAILURE)) {
+	vmx_enter_guest(result);
 
-		print_vmentry_failure_info(failure);
-		abort();
+	if (result->vm_fail) {
+		if (abort_flag & ABORT_ON_EARLY_VMENTRY_FAIL)
+			goto do_abort;
+		return;
 	}
-
-	if (!failure->early && !(vmcs_read(EXI_REASON) & VMX_ENTRY_FAILURE)) {
-		launched = 1;
-		check_for_guest_termination();
+	if (result->exit_reason.failed_vmentry) {
+		if ((abort_flag & ABORT_ON_INVALID_GUEST_STATE) ||
+		    result->exit_reason.basic != VMX_FAIL_STATE)
+			goto do_abort;
+		return;
 	}
+
+	launched = 1;
+	check_for_guest_termination();
+	return;
+
+do_abort:
+	print_vmentry_failure_info(result);
+	abort();
 }
 
 void enter_guest_with_bad_controls(void)
 {
-	struct vmentry_failure failure = {0};
+	struct vmentry_result result;
 
 	TEST_ASSERT_MSG(v2_guest_main,
 			"Never called test_set_guest_func!");
@@ -1878,10 +1888,10 @@  void enter_guest_with_bad_controls(void)
 	TEST_ASSERT_MSG(!guest_finished,
 			"Called enter_guest() after guest returned.");
 
-	__enter_guest(ABORT_ON_INVALID_GUEST_STATE, &failure);
-	report(failure.early, "failure occurred early");
-	report((failure.flags & VMX_ENTRY_FLAGS) == X86_EFLAGS_ZF,
-               "FLAGS set correctly");
+	__enter_guest(ABORT_ON_INVALID_GUEST_STATE, &result);
+	report(result.vm_fail, "VM-Fail occurred as expected");
+	report((result.flags & VMX_ENTRY_FLAGS) == X86_EFLAGS_ZF,
+               "FLAGS set correctly on VM-Fail");
 	report(vmcs_read(VMX_INST_ERROR) == VMXERR_ENTRY_INVALID_CONTROL_FIELD,
 	       "VM-Inst Error # is %d (VM entry with invalid control field(s))",
 	       VMXERR_ENTRY_INVALID_CONTROL_FIELD);
@@ -1893,23 +1903,23 @@  void enter_guest_with_bad_controls(void)
 	 * unexpectedly succeed, it's nice to check whether the guest has
 	 * terminated, to reduce the number of error messages.
 	 */
-	if (!failure.early)
+	if (!result.vm_fail)
 		check_for_guest_termination();
 }
 
 void enter_guest(void)
 {
-	struct vmentry_failure failure = {0};
+	struct vmentry_result result;
 
 	__enter_guest(ABORT_ON_EARLY_VMENTRY_FAIL |
-		      ABORT_ON_INVALID_GUEST_STATE, &failure);
+		      ABORT_ON_INVALID_GUEST_STATE, &result);
 }
 
 void enter_guest_with_invalid_guest_state(void)
 {
-	struct vmentry_failure failure = {0};
+	struct vmentry_result result;
 
-	__enter_guest(ABORT_ON_EARLY_VMENTRY_FAIL, &failure);
+	__enter_guest(ABORT_ON_EARLY_VMENTRY_FAIL, &result);
 }
 
 extern struct vmx_test vmx_tests[];
@@ -1924,6 +1934,8 @@  test_wanted(const char *name, const char *filters[], int filter_count)
 	char *c;
 	const char *n;
 
+	printf("filter = %s, test = %s\n", filters[0], name);
+
 	/* Replace spaces with underscores. */
 	n = name;
 	c = &clean_name[0];
diff --git a/x86/vmx.h b/x86/vmx.h
index 6adf091..c4a0fb4 100644
--- a/x86/vmx.h
+++ b/x86/vmx.h
@@ -44,13 +44,38 @@  struct regs {
 	u64 rflags;
 };
 
-struct vmentry_failure {
-	/* Did a vmlaunch or vmresume fail? */
-	bool vmlaunch;
+struct vmentry_result {
 	/* Instruction mnemonic (for convenience). */
 	const char *instr;
-	/* Did the instruction return right away, or did we jump to HOST_RIP? */
-	bool early;
+	/* Did the test attempt vmlaunch or vmresume? */
+	bool vmlaunch;
+	/* Did the instruction VM-Fail? */
+	bool vm_fail;
+	/* Did the VM-Entry fully enter the guest? */
+	bool entered;
+	/* VM-Exit reason, valid iff !vm_fail */
+	union {
+		struct {
+			u32	basic			: 16;
+			u32	reserved16		: 1;
+			u32	reserved17		: 1;
+			u32	reserved18		: 1;
+			u32	reserved19		: 1;
+			u32	reserved20		: 1;
+			u32	reserved21		: 1;
+			u32	reserved22		: 1;
+			u32	reserved23		: 1;
+			u32	reserved24		: 1;
+			u32	reserved25		: 1;
+			u32	reserved26		: 1;
+			u32	enclave_mode		: 1;
+			u32	smi_pending_mtf		: 1;
+			u32	smi_from_vmx_root	: 1;
+			u32	reserved30		: 1;
+			u32	failed_vmentry		: 1;
+		};
+		u32 full;
+	} exit_reason;
 	/* Contents of [re]flags after failed entry. */
 	unsigned long flags;
 };
@@ -62,7 +87,7 @@  struct vmx_test {
 	int (*exit_handler)(void);
 	void (*syscall_handler)(u64 syscall_no);
 	struct regs guest_regs;
-	int (*entry_failure_handler)(struct vmentry_failure *failure);
+	int (*entry_failure_handler)(struct vmentry_result *result);
 	struct vmcs *vmcs;
 	int exits;
 	/* Alternative test interface. */
@@ -800,7 +825,7 @@  void init_vmx(u64 *vmxon_region);
 
 const char *exit_reason_description(u64 reason);
 void print_vmexit_info(void);
-void print_vmentry_failure_info(struct vmentry_failure *failure);
+void print_vmentry_failure_info(struct vmentry_result *result);
 void ept_sync(int type, u64 eptp);
 void vpid_sync(int type, u16 vpid);
 void install_ept_entry(unsigned long *pml4, int pte_level,
diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index a7abd63..c4077b1 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -1996,24 +1996,22 @@  static int msr_switch_exit_handler(void)
 	return VMX_TEST_EXIT;
 }
 
-static int msr_switch_entry_failure(struct vmentry_failure *failure)
+static int msr_switch_entry_failure(struct vmentry_result *result)
 {
-	ulong reason;
-
-	if (failure->early) {
-		printf("ERROR %s: early exit\n", __func__);
+	if (result->vm_fail) {
+		printf("ERROR %s: VM-Fail on %s\n", __func__, result->instr);
 		return VMX_TEST_EXIT;
 	}
 
-	reason = vmcs_read(EXI_REASON);
-	if (reason == (VMX_ENTRY_FAILURE | VMX_FAIL_MSR) &&
+	if (result->exit_reason.failed_vmentry &&
+	    result->exit_reason.basic == VMX_FAIL_MSR &&
 	    vmx_get_test_stage() == 3) {
 		report(vmcs_read(EXI_QUALIFICATION) == 1,
 		       "VM entry MSR load: try to load FS_BASE");
 		return VMX_TEST_VMEXIT;
 	}
-	printf("ERROR %s: unexpected stage=%u or reason=%lu\n",
-		__func__, vmx_get_test_stage(), reason);
+	printf("ERROR %s: unexpected stage=%u or reason=%x\n",
+		__func__, vmx_get_test_stage(), result->exit_reason.full);
 	return VMX_TEST_EXIT;
 }
 
@@ -9428,12 +9426,10 @@  static int invalid_msr_exit_handler(void)
 	return VMX_TEST_EXIT;
 }
 
-static int invalid_msr_entry_failure(struct vmentry_failure *failure)
+static int invalid_msr_entry_failure(struct vmentry_result *result)
 {
-	ulong reason;
-
-	reason = vmcs_read(EXI_REASON);
-	report(reason == (0x80000000u | VMX_FAIL_MSR), "Invalid MSR load");
+	report(result->exit_reason.failed_vmentry &&
+	       result->exit_reason.basic == VMX_FAIL_MSR, "Invalid MSR load");
 	return VMX_TEST_VMEXIT;
 }