KVM: arm/arm64: Reset mapped IRQs on VM reset

We currently don't allow resetting mapped IRQs from userspace, because
their state is controlled by the hardware.  But we do need to reset the
state when the VM is reset, so we provide a function for the 'owner' of
the mapped interrupt to reset the interrupt state.

Currently only the timer uses mapped interrupts, so we call this
function from the timer reset logic.

Cc: stable@vger.kernel.org
Fixes: 4c60e360d6df ("KVM: arm/arm64: Provide a get_input_level for the arch timer")
Signed-off-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index cdbd142ca7f2ea4513a7bcf44f877f9b3bbbebc3..02924ae2527e6580a553814d30fab930af071a19 100644 (file)
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -360,6 +360,7 @@ void kvm_vgic_put(struct kvm_vcpu *vcpu);
 bool kvm_vcpu_has_pending_irqs(struct kvm_vcpu *vcpu);
 void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu);
 void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu);
+void kvm_vgic_reset_mapped_irq(struct kvm_vcpu *vcpu, u32 vintid);
 
 void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg);
 

diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 70f4c30918eb2682b638c326977b50e3568c7638..3945021510a958fc6f1ac8270cbe46a51aa45230 100644 (file)
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -581,6 +581,7 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
 
 int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
 {
+       struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
        struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
        struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
 
@@ -594,6 +595,9 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
        ptimer->cnt_ctl = 0;
        kvm_timer_update_state(vcpu);
 
+       if (timer->enabled && irqchip_in_kernel(vcpu->kvm))
+               kvm_vgic_reset_mapped_irq(vcpu, vtimer->irq.irq);
+
        return 0;
 }
 

diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index c7c5ef190afa0c3984d5b9051f59ca72c696eb20..0001858a2c23de22186be76ab2d6c7f1597868cb 100644 (file)
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -495,6 +495,32 @@ int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq,
        return ret;
 }
 
+/**
+ * kvm_vgic_reset_mapped_irq - Reset a mapped IRQ
+ * @vcpu: The VCPU pointer
+ * @vintid: The INTID of the interrupt
+ *
+ * Reset the active and pending states of a mapped interrupt.  Kernel
+ * subsystems injecting mapped interrupts should reset their interrupt lines
+ * when we are doing a reset of the VM.
+ */
+void kvm_vgic_reset_mapped_irq(struct kvm_vcpu *vcpu, u32 vintid)
+{
+       struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
+       unsigned long flags;
+
+       if (!irq->hw)
+               goto out;
+
+       spin_lock_irqsave(&irq->irq_lock, flags);
+       irq->active = false;
+       irq->pending_latch = false;
+       irq->line_level = false;
+       spin_unlock_irqrestore(&irq->irq_lock, flags);
+out:
+       vgic_put_irq(vcpu->kvm, irq);
+}
+
 int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid)
 {
        struct vgic_irq *irq;