1 files changed, 36 insertions, 25 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 887f3b0c2b60..c6a91b044d8d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1855,8 +1855,7 @@ void kvm_set_pfn_dirty(kvm_pfn_t pfn)
 	if (!kvm_is_reserved_pfn(pfn)) {
 		struct page *page = pfn_to_page(pfn);
 
-		if (!PageReserved(page))
-			SetPageDirty(page);
+		SetPageDirty(page);
 	}
 }
 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
@@ -2477,6 +2476,29 @@ static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
 #endif
 }
 
+/*
+ * Unlike kvm_arch_vcpu_runnable, this function is called outside
+ * a vcpu_load/vcpu_put pair.  However, for most architectures
+ * kvm_arch_vcpu_runnable does not require vcpu_load.
+ */
+bool __weak kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
+{
+	return kvm_arch_vcpu_runnable(vcpu);
+}
+
+static bool vcpu_dy_runnable(struct kvm_vcpu *vcpu)
+{
+	if (kvm_arch_dy_runnable(vcpu))
+		return true;
+
+#ifdef CONFIG_KVM_ASYNC_PF
+	if (!list_empty_careful(&vcpu->async_pf.done))
+		return true;
+#endif
+
+	return false;
+}
+
 void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode)
 {
 	struct kvm *kvm = me->kvm;
@@ -2506,9 +2528,10 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode)
 				continue;
 			if (vcpu == me)
 				continue;
-			if (swait_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
+			if (swait_active(&vcpu->wq) && !vcpu_dy_runnable(vcpu))
 				continue;
-			if (yield_to_kernel_mode && !kvm_arch_vcpu_in_kernel(vcpu))
+			if (READ_ONCE(vcpu->preempted) && yield_to_kernel_mode &&
+				!kvm_arch_vcpu_in_kernel(vcpu))
 				continue;
 			if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
 				continue;
@@ -2591,30 +2614,20 @@ static int create_vcpu_fd(struct kvm_vcpu *vcpu)
 	return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
 }
 
-static int kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
+static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
 {
+#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
 	char dir_name[ITOA_MAX_LEN * 2];
-	int ret;
-
-	if (!kvm_arch_has_vcpu_debugfs())
-		return 0;
 
 	if (!debugfs_initialized())
-		return 0;
+		return;
 
 	snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
 	vcpu->debugfs_dentry = debugfs_create_dir(dir_name,
-								vcpu->kvm->debugfs_dentry);
-	if (!vcpu->debugfs_dentry)
-		return -ENOMEM;
-
-	ret = kvm_arch_create_vcpu_debugfs(vcpu);
-	if (ret < 0) {
-		debugfs_remove_recursive(vcpu->debugfs_dentry);
-		return ret;
-	}
+						  vcpu->kvm->debugfs_dentry);
 
-	return 0;
+	kvm_arch_create_vcpu_debugfs(vcpu);
+#endif
 }
 
 /*
@@ -2649,9 +2662,7 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
 	if (r)
 		goto vcpu_destroy;
 
-	r = kvm_create_vcpu_debugfs(vcpu);
-	if (r)
-		goto vcpu_destroy;
+	kvm_create_vcpu_debugfs(vcpu);
 
 	mutex_lock(&kvm->lock);
 	if (kvm_get_vcpu_by_id(kvm, id)) {
@@ -4205,7 +4216,7 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
 {
 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
 
-	vcpu->preempted = false;
+	WRITE_ONCE(vcpu->preempted, false);
 	WRITE_ONCE(vcpu->ready, false);
 
 	kvm_arch_sched_in(vcpu, cpu);
@@ -4219,7 +4230,7 @@ static void kvm_sched_out(struct preempt_notifier *pn,
 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
 
 	if (current->state == TASK_RUNNING) {
-		vcpu->preempted = true;
+		WRITE_ONCE(vcpu->preempted, true);
 		WRITE_ONCE(vcpu->ready, true);
 	}
 	kvm_arch_vcpu_put(vcpu);