KVM: Use alignment properties of vcpu to simplify FPU ops

Now we use a kmem cache for allocating vcpus, we can get the 16-byte
alignment required by fxsave & fxrstor instructions, and avoid
manually aligning the buffer.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index 8193651..5277084 100644
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -1557,8 +1557,8 @@
 	}
 
 	if (vcpu->fpu_active) {
-		fx_save(vcpu->host_fx_image);
-		fx_restore(vcpu->guest_fx_image);
+		fx_save(&vcpu->host_fx_image);
+		fx_restore(&vcpu->guest_fx_image);
 	}
 
 	asm volatile (
@@ -1670,8 +1670,8 @@
 	vcpu->guest_mode = 0;
 
 	if (vcpu->fpu_active) {
-		fx_save(vcpu->guest_fx_image);
-		fx_restore(vcpu->host_fx_image);
+		fx_save(&vcpu->guest_fx_image);
+		fx_restore(&vcpu->host_fx_image);
 	}
 
 	if ((svm->vmcb->save.dr7 & 0xff))