kvm test: vmexit: enable NX

Marcelo Tosatti
2010-06-08T18:34:57Z

Enable NX to disable MSR autoload/save. This is the common case anyway.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

diff --git a/kvm/test/x86/vmexit.c b/kvm/test/x86/vmexit.c
index c3a01e0..f267a19 100644
--- a/kvm/test/x86/vmexit.c
+++ b/kvm/test/x86/vmexit.c
@@ -45,6 +45,24 @@ static void vmcall(void)
asm volatile ("vmcall" : "+a"(a), "=b"(b), "=c"(c), "=d"(d));
}

+#define MSR_EFER 0xc0000080
+#define EFER_NX_MASK (1ull << 11)
+
+unsigned long long rdmsr(unsigned index)
+{
+ unsigned a, d;
+
+ asm volatile("rdmsr" : "=a"(a), "=d"(d) : "c"(index));
+ return ((unsigned long long)d << 32) | a;
+}
+
+void wrmsr(unsigned index, unsigned long long val)
+{
+ unsigned a = val, d = val >> 32;
+
+ asm volatile("wrmsr" : : "a"(a), "d"(d), "c"(index));
+}
+
static void mov_from_cr8(void)
{
unsigned long cr8;
@@ -151,12 +169,20 @@ static void do_test(struct test *test)

#define ARRAY_SIZE(_x) (sizeof(_x) / sizeof((_x)[0]))

+static void enable_nx(void *junk)
+{
+ wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NX_MASK);
+}
+
int main(void)
{
int i;

smp_init();

+ for (i = cpu_count(); i > 0; i--)
+ on_cpu(i-1, enable_nx, 0);
+
for (i = 0; i < ARRAY_SIZE(tests); ++i)
do_test(&tests[i]);