4 files changed, 31 insertions, 0 deletions

diff --git a/arch/x86/include/asm/kvm.h b/arch/x86/include/asm/kvm.h
index 32eb96c7ca27..54bcf2281526 100644
--- a/arch/x86/include/asm/kvm.h
+++ b/arch/x86/include/asm/kvm.h
@@ -233,4 +233,9 @@ struct kvm_guest_debug_arch {
 struct kvm_pit_state {
         struct kvm_pit_channel_state channels[3];
 };
+
+struct kvm_reinject_control {
+        __u8 pit_reinject;
+        __u8 reserved[31];
+};
 #endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 72bd275a9b5c..528daadeba49 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -201,6 +201,9 @@ static int __pit_timer_fn(struct kvm_kpit_state *ps)
         if (!atomic_inc_and_test(&pt->pending))
                 set_bit(KVM_REQ_PENDING_TIMER, &vcpu0->requests);
 
+        if (!pt->reinject)
+                atomic_set(&pt->pending, 1);
+
         if (vcpu0 && waitqueue_active(&vcpu0->wq))
                 wake_up_interruptible(&vcpu0->wq);
 
@@ -580,6 +583,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm)
         pit_state->irq_ack_notifier.gsi = 0;
         pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq;
         kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
+        pit_state->pit_timer.reinject = true;
         mutex_unlock(&pit->pit_state.lock);
 
         kvm_pit_reset(pit);
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index 4178022b97aa..76959c4b500e 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -9,6 +9,7 @@ struct kvm_kpit_timer {
         s64 period; /* unit: ns */
         s64 scheduled;
         atomic_t pending;
+        bool reinject;
 };
 
 struct kvm_kpit_channel_state {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c3fbe8c55c13..a1f14611f4b9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -993,6 +993,7 @@ int kvm_dev_ioctl_check_extension(long ext)
         case KVM_CAP_NOP_IO_DELAY:
         case KVM_CAP_MP_STATE:
         case KVM_CAP_SYNC_MMU:
+        case KVM_CAP_REINJECT_CONTROL:
                 r = 1;
                 break;
         case KVM_CAP_COALESCED_MMIO:
@@ -1728,6 +1729,15 @@ static int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
         return r;
 }
 
+static int kvm_vm_ioctl_reinject(struct kvm *kvm,
+                                 struct kvm_reinject_control *control)
+{
+        if (!kvm->arch.vpit)
+                return -ENXIO;
+        kvm->arch.vpit->pit_state.pit_timer.reinject = control->pit_reinject;
+        return 0;
+}
+
 /*
  * Get (and clear) the dirty memory log for a memory slot.
  */
@@ -1925,6 +1935,17 @@ long kvm_arch_vm_ioctl(struct file *filp,
                 r = 0;
                 break;
         }
+        case KVM_REINJECT_CONTROL: {
+                struct kvm_reinject_control control;
+                r =  -EFAULT;
+                if (copy_from_user(&control, argp, sizeof(control)))
+                        goto out;
+                r = kvm_vm_ioctl_reinject(kvm, &control);
+                if (r)
+                        goto out;
+                r = 0;
+                break;
+        }
         default:
                 ;
         }