Merge tag 'v3.16-rc4' into drm-intel-next-queued

Due to Dave's vacation drm-next hasn't opened yet for 3.17 so I
couldn't move my drm-intel-next queue forward yet like I usually do.
Just pull in the latest upstream -rc to unblock patch merging - I
don't want to needlessly rebase my current patch pile really and void
all the testing we've done already.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 35 insertions, 29 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7f4f9c2bada..b5e994ad013 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)
@@ -1476,6 +1462,7 @@ static void svm_get_segment(struct kvm_vcpu *vcpu,
 		 */
 		if (var->unusable)
 			var->db = 0;
+		var->dpl = to_svm(vcpu)->vmcb->save.cpl;
 		break;
 	}
 }
@@ -1631,8 +1618,15 @@ 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 +2764,6 @@ 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 +3275,24 @@ 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 +3350,8 @@ 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,
 };