KVM: VMX: Properly shadow the CR0 register in the vcpu struct

Set all of the host mask bits for CR0 so that we can maintain a proper
shadow of CR0.  This exposes CR0.TS, paving the way for lazy fpu handling.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index d28c848138ce..09608114e29a 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -810,11 +810,8 @@ static void exit_lmode(struct kvm_vcpu *vcpu)
 
 #endif
 
-static void vmx_decache_cr0_cr4_guest_bits(struct kvm_vcpu *vcpu)
+static void vmx_decache_cr4_guest_bits(struct kvm_vcpu *vcpu)
 {
-        vcpu->cr0 &= KVM_GUEST_CR0_MASK;
-        vcpu->cr0 |= vmcs_readl(GUEST_CR0) & ~KVM_GUEST_CR0_MASK;
-
         vcpu->cr4 &= KVM_GUEST_CR4_MASK;
         vcpu->cr4 |= vmcs_readl(GUEST_CR4) & ~KVM_GUEST_CR4_MASK;
 }
@@ -1205,7 +1202,7 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu)
         vmcs_writel(TPR_THRESHOLD, 0);
 #endif
 
-        vmcs_writel(CR0_GUEST_HOST_MASK, KVM_GUEST_CR0_MASK);
+        vmcs_writel(CR0_GUEST_HOST_MASK, ~0UL);
         vmcs_writel(CR4_GUEST_HOST_MASK, KVM_GUEST_CR4_MASK);
 
         vcpu->cr0 = 0x60000010;
@@ -1557,6 +1554,11 @@ static int handle_cr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                         return 1;
                 };
                 break;
+        case 2: /* clts */
+                vcpu_load_rsp_rip(vcpu);
+                set_cr0(vcpu, vcpu->cr0 & ~CR0_TS_MASK);
+                skip_emulated_instruction(vcpu);
+                return 1;
         case 1: /*mov from cr*/
                 switch (cr) {
                 case 3:
@@ -2112,7 +2114,7 @@ static struct kvm_arch_ops vmx_arch_ops = {
         .get_segment = vmx_get_segment,
         .set_segment = vmx_set_segment,
         .get_cs_db_l_bits = vmx_get_cs_db_l_bits,
-        .decache_cr0_cr4_guest_bits = vmx_decache_cr0_cr4_guest_bits,
+        .decache_cr4_guest_bits = vmx_decache_cr4_guest_bits,
         .set_cr0 = vmx_set_cr0,
         .set_cr3 = vmx_set_cr3,
         .set_cr4 = vmx_set_cr4,