summaryrefslogtreecommitdiff
path: root/arch/x86/kvm/svm.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/svm.c')
-rw-r--r--arch/x86/kvm/svm.c63
1 files changed, 34 insertions, 29 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7f4f9c2badae..ec8366c5cfea 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1338,21 +1338,6 @@ static void svm_vcpu_put(struct kvm_vcpu *vcpu)
wrmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]);
}
-static void svm_update_cpl(struct kvm_vcpu *vcpu)
-{
- struct vcpu_svm *svm = to_svm(vcpu);
- int cpl;
-
- if (!is_protmode(vcpu))
- cpl = 0;
- else if (svm->vmcb->save.rflags & X86_EFLAGS_VM)
- cpl = 3;
- else
- cpl = svm->vmcb->save.cs.selector & 0x3;
-
- svm->vmcb->save.cpl = cpl;
-}
-
static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu)
{
return to_svm(vcpu)->vmcb->save.rflags;
@@ -1360,11 +1345,12 @@ static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu)
static void svm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
{
- unsigned long old_rflags = to_svm(vcpu)->vmcb->save.rflags;
-
+ /*
+ * Any change of EFLAGS.VM is accompained by a reload of SS
+ * (caused by either a task switch or an inter-privilege IRET),
+ * so we do not need to update the CPL here.
+ */
to_svm(vcpu)->vmcb->save.rflags = rflags;
- if ((old_rflags ^ rflags) & X86_EFLAGS_VM)
- svm_update_cpl(vcpu);
}
static void svm_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
@@ -1631,8 +1617,15 @@ static void svm_set_segment(struct kvm_vcpu *vcpu,
s->attrib |= (var->db & 1) << SVM_SELECTOR_DB_SHIFT;
s->attrib |= (var->g & 1) << SVM_SELECTOR_G_SHIFT;
}
- if (seg == VCPU_SREG_CS)
- svm_update_cpl(vcpu);
+
+ /*
+ * This is always accurate, except if SYSRET returned to a segment
+ * with SS.DPL != 3. Intel does not have this quirk, and always
+ * forces SS.DPL to 3 on sysret, so we ignore that case; fixing it
+ * would entail passing the CPL to userspace and back.
+ */
+ if (seg == VCPU_SREG_SS)
+ svm->vmcb->save.cpl = (s->attrib >> SVM_SELECTOR_DPL_SHIFT) & 3;
mark_dirty(svm->vmcb, VMCB_SEG);
}
@@ -2770,12 +2763,6 @@ static int xsetbv_interception(struct vcpu_svm *svm)
return 1;
}
-static int invalid_op_interception(struct vcpu_svm *svm)
-{
- kvm_queue_exception(&svm->vcpu, UD_VECTOR);
- return 1;
-}
-
static int task_switch_interception(struct vcpu_svm *svm)
{
u16 tss_selector;
@@ -3287,6 +3274,24 @@ static int pause_interception(struct vcpu_svm *svm)
return 1;
}
+static int nop_interception(struct vcpu_svm *svm)
+{
+ skip_emulated_instruction(&(svm->vcpu));
+ return 1;
+}
+
+static int monitor_interception(struct vcpu_svm *svm)
+{
+ printk_once(KERN_WARNING "kvm: MONITOR instruction emulated as NOP!\n");
+ return nop_interception(svm);
+}
+
+static int mwait_interception(struct vcpu_svm *svm)
+{
+ printk_once(KERN_WARNING "kvm: MWAIT instruction emulated as NOP!\n");
+ return nop_interception(svm);
+}
+
static int (*const svm_exit_handlers[])(struct vcpu_svm *svm) = {
[SVM_EXIT_READ_CR0] = cr_interception,
[SVM_EXIT_READ_CR3] = cr_interception,
@@ -3344,8 +3349,8 @@ static int (*const svm_exit_handlers[])(struct vcpu_svm *svm) = {
[SVM_EXIT_CLGI] = clgi_interception,
[SVM_EXIT_SKINIT] = skinit_interception,
[SVM_EXIT_WBINVD] = emulate_on_interception,
- [SVM_EXIT_MONITOR] = invalid_op_interception,
- [SVM_EXIT_MWAIT] = invalid_op_interception,
+ [SVM_EXIT_MONITOR] = monitor_interception,
+ [SVM_EXIT_MWAIT] = mwait_interception,
[SVM_EXIT_XSETBV] = xsetbv_interception,
[SVM_EXIT_NPF] = pf_interception,
};