7 files changed, 44 insertions, 0 deletions

diff --git a/arch/x86/include/asm/entry_arch.h b/arch/x86/include/asm/entry_arch.h
index 40afa0005c69..9bd4ecac72be 100644
--- a/arch/x86/include/asm/entry_arch.h
+++ b/arch/x86/include/asm/entry_arch.h
@@ -19,6 +19,10 @@ BUILD_INTERRUPT(reboot_interrupt,REBOOT_VECTOR)
 
 BUILD_INTERRUPT(x86_platform_ipi, X86_PLATFORM_IPI_VECTOR)
 
+#ifdef CONFIG_HAVE_KVM
+BUILD_INTERRUPT(kvm_posted_intr_ipi, POSTED_INTR_VECTOR)
+#endif
+
 /*
  * every pentium local APIC has two 'local interrupts', with a
  * soft-definable vector attached to both interrupts, one of
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index 81f04cee5f74..ab0ae1aa6d0a 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -12,6 +12,9 @@ typedef struct {
         unsigned int irq_spurious_count;
         unsigned int icr_read_retry_count;
 #endif
+#ifdef CONFIG_HAVE_KVM
+        unsigned int kvm_posted_intr_ipis;
+#endif
         unsigned int x86_platform_ipis; /* arch dependent */
         unsigned int apic_perf_irqs;
         unsigned int apic_irq_work_irqs;
diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index 10a78c3d3d5a..1da97efad08a 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -28,6 +28,7 @@
 /* Interrupt handlers registered during init_IRQ */
 extern void apic_timer_interrupt(void);
 extern void x86_platform_ipi(void);
+extern void kvm_posted_intr_ipi(void);
 extern void error_interrupt(void);
 extern void irq_work_interrupt(void);
 
diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index aac5fa62a86c..5702d7e3111d 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -102,6 +102,11 @@
  */
 #define X86_PLATFORM_IPI_VECTOR         0xf7
 
+/* Vector for KVM to deliver posted interrupt IPI */
+#ifdef CONFIG_HAVE_KVM
+#define POSTED_INTR_VECTOR              0xf2
+#endif
+
 /*
  * IRQ work vector:
  */
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index c1d01e6ca790..727208941030 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1166,6 +1166,11 @@ apicinterrupt LOCAL_TIMER_VECTOR \
 apicinterrupt X86_PLATFORM_IPI_VECTOR \
         x86_platform_ipi smp_x86_platform_ipi
 
+#ifdef CONFIG_HAVE_KVM
+apicinterrupt POSTED_INTR_VECTOR \
+        kvm_posted_intr_ipi smp_kvm_posted_intr_ipi
+#endif
+
 apicinterrupt THRESHOLD_APIC_VECTOR \
         threshold_interrupt smp_threshold_interrupt
 apicinterrupt THERMAL_APIC_VECTOR \
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index e4595f105910..6ae6ea1d27d9 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -228,6 +228,28 @@ void smp_x86_platform_ipi(struct pt_regs *regs)
         set_irq_regs(old_regs);
 }
 
+#ifdef CONFIG_HAVE_KVM
+/*
+ * Handler for POSTED_INTERRUPT_VECTOR.
+ */
+void smp_kvm_posted_intr_ipi(struct pt_regs *regs)
+{
+        struct pt_regs *old_regs = set_irq_regs(regs);
+
+        ack_APIC_irq();
+
+        irq_enter();
+
+        exit_idle();
+
+        inc_irq_stat(kvm_posted_intr_ipis);
+
+        irq_exit();
+
+        set_irq_regs(old_regs);
+}
+#endif
+
 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
 
 #ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
index 7dc4e459c2b3..a2a1fbc594ff 100644
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c
@@ -172,6 +172,10 @@ static void __init apic_intr_init(void)
 
         /* IPI for X86 platform specific use */
         alloc_intr_gate(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi);
+#ifdef CONFIG_HAVE_KVM
+        /* IPI for KVM to deliver posted interrupt */
+        alloc_intr_gate(POSTED_INTR_VECTOR, kvm_posted_intr_ipi);
+#endif
 
         /* IPI vectors for APIC spurious and error interrupts */
         alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);