[PATCH] test: Add XSAVE unit test

[PATCH] test: Add XSAVE unit test

[Sheng Yang]

Only test legal action so far, we can extend it later.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
---
 kvm/test/config-x86-common.mak |    5 +-
 kvm/test/x86/xsave.c           |  173 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 177 insertions(+), 1 deletions(-)
 create mode 100644 kvm/test/x86/xsave.c

diff --git a/kvm/test/config-x86-common.mak b/kvm/test/config-x86-common.mak
index 9084e2d..2110e4e 100644
--- a/kvm/test/config-x86-common.mak
+++ b/kvm/test/config-x86-common.mak
@@ -24,7 +24,8 @@ FLATLIBS = lib/libcflat.a $(libgcc)
 
 tests-common = $(TEST_DIR)/vmexit.flat $(TEST_DIR)/tsc.flat \
                $(TEST_DIR)/smptest.flat  $(TEST_DIR)/port80.flat \
-               $(TEST_DIR)/realmode.flat $(TEST_DIR)/msr.flat
+               $(TEST_DIR)/realmode.flat $(TEST_DIR)/msr.flat \
+               $(TEST_DIR)/xsave.flat
 
 test_cases: $(tests-common) $(tests)
 
@@ -58,6 +59,8 @@ $(TEST_DIR)/realmode.o: bits = 32
 
 $(TEST_DIR)/msr.flat: $(cstart.o) $(TEST_DIR)/msr.o
 
+$(TEST_DIR)/xsave.flat: $(cstart.o) $(TEST_DIR)/xsave.o
+
 arch_clean:
 	$(RM) $(TEST_DIR)/*.o $(TEST_DIR)/*.flat \
 	$(TEST_DIR)/.*.d $(TEST_DIR)/lib/.*.d $(TEST_DIR)/lib/*.o
diff --git a/kvm/test/x86/xsave.c b/kvm/test/x86/xsave.c
new file mode 100644
index 0000000..2d6ea07
--- /dev/null
+++ b/kvm/test/x86/xsave.c
@@ -0,0 +1,173 @@
+#include "libcflat.h"
+
+#ifdef __x86_64__
+#define uint64_t unsigned long
+#else
+#define uint64_t unsigned long long
+#endif
+
+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+				unsigned int *ecx, unsigned int *edx)
+{
+	/* ecx is often an input as well as an output. */
+	asm volatile("cpuid"
+	    : "=a" (*eax),
+	      "=b" (*ebx),
+	      "=c" (*ecx),
+	      "=d" (*edx)
+	    : "0" (*eax), "2" (*ecx));
+}
+
+/*
+ * Generic CPUID function
+ * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
+ * resulting in stale register contents being returned.
+ */
+void cpuid(unsigned int op,
+		 unsigned int *eax, unsigned int *ebx,
+		 unsigned int *ecx, unsigned int *edx)
+{
+	*eax = op;
+	*ecx = 0;
+	__cpuid(eax, ebx, ecx, edx);
+}
+
+/* Some CPUID calls want 'count' to be placed in ecx */
+void cpuid_count(unsigned int op, int count,
+		       unsigned int *eax, unsigned int *ebx,
+		       unsigned int *ecx, unsigned int *edx)
+{
+	*eax = op;
+	*ecx = count;
+	__cpuid(eax, ebx, ecx, edx);
+}
+
+u64 xgetbv(u32 index)
+{
+	u32 eax, edx;
+
+	asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */
+		     : "=a" (eax), "=d" (edx)
+		     : "c" (index));
+	return eax + ((u64)edx << 32);
+}
+
+void xsetbv(u32 index, u64 value)
+{
+	u32 eax = value;
+	u32 edx = value >> 32;
+
+	asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */
+		     : : "a" (eax), "d" (edx), "c" (index));
+}
+
+unsigned long read_cr4(void)
+{
+	unsigned long val;
+	asm volatile("mov %%cr4,%0" : "=r" (val));
+	return val;
+}
+
+void write_cr4(unsigned long val)
+{
+	asm volatile("mov %0,%%cr4": : "r" (val));
+}
+
+#define CPUID_1_ECX_XSAVE	    (1 << 26)
+int check_xsave()
+{
+	unsigned int eax, ebx, ecx, edx;
+	cpuid(1, &eax, &ebx, &ecx, &edx);
+	if (ecx & CPUID_1_ECX_XSAVE)
+		return 1;
+	return 0;
+}
+
+uint64_t get_supported_xcr0()
+{
+	unsigned int eax, ebx, ecx, edx;
+	cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
+	printf("eax %x, ebx %x, ecx %x, edx %x\n",
+		eax, ebx, ecx, edx);
+	return eax + ((u64)edx << 32);
+}
+
+#define X86_CR4_OSXSAVE			0x00040000
+#define XCR_XFEATURE_ENABLED_MASK       0x00000000
+
+#define XSTATE_FP       0x1
+#define XSTATE_SSE      0x2
+#define XSTATE_YMM      0x4
+
+static unsigned int fault_mask;
+
+void pass_if(int condition)
+{
+	if (condition)
+		printf("Pass!\n");
+	else
+		printf("Fail!\n");
+}
+
+void pass_if_no_fault(void)
+{
+	pass_if(!fault_mask);
+	fault_mask = 0;
+}
+
+void pass_if_fault(unsigned int fault_bit)
+{
+	pass_if(fault_mask & fault_bit);
+	fault_mask = 0;
+}
+
+#define UD_VECTOR_MASK	    (1 << 6)
+#define GP_VECTOR_MASK	    (1 << 13)
+
+void test_xsave()
+{
+	unsigned int cr4;
+	uint64_t supported_xcr0;
+	uint64_t test_bits;
+
+	supported_xcr0 = get_supported_xcr0();
+	printf("Supported XCR0 bits: 0x%x\n", supported_xcr0);
+
+	printf("Check minimal XSAVE required bits: ");
+	test_bits = XSTATE_FP | XSTATE_SSE | XSTATE_YMM;
+	pass_if((supported_xcr0 & test_bits) == test_bits);
+
+	printf("Check CR4 OSXSAVE: ");
+	cr4 = read_cr4();
+	write_cr4(cr4 | X86_CR4_OSXSAVE);
+	pass_if_no_fault();
+
+	printf("Check XSETBV for XCR0 bits\n");
+	printf("    Legal tests\n");
+	printf("    XSTATE_FP: ");
+	test_bits = XSTATE_FP;
+	xsetbv(XCR_XFEATURE_ENABLED_MASK, test_bits);
+	pass_if_no_fault();
+	printf("    XSTATE_FP | XSTATE_SSE: ");
+	test_bits = XSTATE_FP | XSTATE_SSE;
+	xsetbv(XCR_XFEATURE_ENABLED_MASK, test_bits);
+	pass_if_no_fault();
+	printf("    XSTATE_FP | XSTATE_SSE | XSTATE_YMM: ");
+	test_bits = XSTATE_FP | XSTATE_SSE | XSTATE_YMM;
+	xsetbv(XCR_XFEATURE_ENABLED_MASK, test_bits);
+	pass_if_no_fault();
+}
+
+int main()
+{
+	int cpuid_has_xsave;
+
+	cpuid_has_xsave = check_xsave();
+	if (cpuid_has_xsave) {
+		printf("CPU has XSAVE feature\n");
+		test_xsave();
+	} else
+		printf("CPU don't has XSAVE feature\n");
+	return 0;
+}
+
-- 
1.7.0.1

Re: [PATCH] test: Add XSAVE unit test

[Avi Kivity]

On 05/31/2010 02:17 PM, Sheng Yang wrote:
> Only test legal action so far, we can extend it later.
>    

The legal actions are tested by guests, so it's more important for unit 
tests to check illegal (and potentially subversive) actions.

> +
> +void test_xsave()
> +{
> +	unsigned int cr4;
> +	uint64_t supported_xcr0;
> +	uint64_t test_bits;
> +
> +	supported_xcr0 = get_supported_xcr0();
> +	printf("Supported XCR0 bits: 0x%x\n", supported_xcr0);
> +
> +	printf("Check minimal XSAVE required bits: ");
> +	test_bits = XSTATE_FP | XSTATE_SSE | XSTATE_YMM;
> +	pass_if((supported_xcr0&  test_bits) == test_bits);
>    

This will fail on a cpu without YMM but with xsave.

> +
> +int main()
> +{
> +	int cpuid_has_xsave;
> +
> +	cpuid_has_xsave = check_xsave();
> +	if (cpuid_has_xsave) {
> +		printf("CPU has XSAVE feature\n");
> +		test_xsave();
> +	} else
> +		printf("CPU don't has XSAVE feature\n");
> +	return 0;
>    

Should return 1 if any failure for autotest integration.

> +}
> +
>    


-- 
error compiling committee.c: too many arguments to function

Re: [PATCH] test: Add XSAVE unit test

[Sheng Yang]

On Tuesday 01 June 2010 16:51:05 Avi Kivity wrote:
> On 05/31/2010 02:17 PM, Sheng Yang wrote:
> > Only test legal action so far, we can extend it later.
> 
> The legal actions are tested by guests, so it's more important for unit
> tests to check illegal (and potentially subversive) actions.

Yes. This is just the first step. I think we need construct IDT and use something 
similar to fixup exception table. That's not a quick work, and we need some base 
for it.
> 
> > +
> > +void test_xsave()
> > +{
> > +	unsigned int cr4;
> > +	uint64_t supported_xcr0;
> > +	uint64_t test_bits;
> > +
> > +	supported_xcr0 = get_supported_xcr0();
> > +	printf("Supported XCR0 bits: 0x%x\n", supported_xcr0);
> > +
> > +	printf("Check minimal XSAVE required bits: ");
> > +	test_bits = XSTATE_FP | XSTATE_SSE | XSTATE_YMM;
> > +	pass_if((supported_xcr0&  test_bits) == test_bits);
> 
> This will fail on a cpu without YMM but with xsave.

Yes, would discard this...
> 
> > +
> > +int main()
> > +{
> > +	int cpuid_has_xsave;
> > +
> > +	cpuid_has_xsave = check_xsave();
> > +	if (cpuid_has_xsave) {
> > +		printf("CPU has XSAVE feature\n");
> > +		test_xsave();
> > +	} else
> > +		printf("CPU don't has XSAVE feature\n");
> > +	return 0;
> 
> Should return 1 if any failure for autotest integration.

OK
> 
> > +}
> > +

--
regards
Yang, Sheng

Re: [PATCH] test: Add XSAVE unit test

[Avi Kivity]

On 06/01/2010 12:00 PM, Sheng Yang wrote:
> On Tuesday 01 June 2010 16:51:05 Avi Kivity wrote:
>    
>> On 05/31/2010 02:17 PM, Sheng Yang wrote:
>>      
>>> Only test legal action so far, we can extend it later.
>>>        
>> The legal actions are tested by guests, so it's more important for unit
>> tests to check illegal (and potentially subversive) actions.
>>      
> Yes. This is just the first step. I think we need construct IDT and use something
> similar to fixup exception table. That's not a quick work, and we need some base
> for it.
>    

Sure, it's fine to proceed in steps.  We do need a framework for 
trapping exceptions.  There's a bit in access.flat (also for running 
code from cpl 3), we could generalize it.

-- 
error compiling committee.c: too many arguments to function