diff options
Diffstat (limited to 'arch/arm/kvm')
| -rw-r--r-- | arch/arm/kvm/vgic.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/arm/kvm/vgic.c b/arch/arm/kvm/vgic.c index 8f32702108b2..2d5e29f1c28f 100644 --- a/arch/arm/kvm/vgic.c +++ b/arch/arm/kvm/vgic.c @@ -71,6 +71,7 @@ #define ACCESS_WRITE_VALUE (3 << 1) #define ACCESS_WRITE_MASK(x) ((x) & (3 << 1)) +static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu); static void vgic_update_state(struct kvm *kvm); static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg); @@ -353,6 +354,7 @@ static bool handle_mmio_clear_enable_reg(struct kvm_vcpu *vcpu, if (mmio->is_write) { if (offset < 4) /* Force SGI enabled */ *reg |= 0xffff; + vgic_retire_disabled_irqs(vcpu); vgic_update_state(vcpu->kvm); return true; } @@ -804,6 +806,34 @@ static void vgic_update_state(struct kvm *kvm) (((lr) & GICH_LR_PHYSID_CPUID) >> GICH_LR_PHYSID_CPUID_SHIFT) #define MK_LR_PEND(src, irq) \ (GICH_LR_PENDING_BIT | ((src) << GICH_LR_PHYSID_CPUID_SHIFT) | (irq)) + +/* + * An interrupt may have been disabled after being made pending on the + * CPU interface (the classic case is a timer running while we're + * rebooting the guest - the interrupt would kick as soon as the CPU + * interface gets enabled, with deadly consequences). + * + * The solution is to examine already active LRs, and check the + * interrupt is still enabled. If not, just retire it. + */ +static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu) +{ + struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; + int lr; + + for_each_set_bit(lr, vgic_cpu->lr_used, vgic_cpu->nr_lr) { + int irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID; + + if (!vgic_irq_is_enabled(vcpu, irq)) { + vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY; + clear_bit(lr, vgic_cpu->lr_used); + vgic_cpu->vgic_lr[lr] &= ~GICH_LR_STATE; + if (vgic_irq_is_active(vcpu, irq)) + vgic_irq_clear_active(vcpu, irq); + } + } +} + /* * Queue an interrupt to a CPU virtual interface. Return true on success, * or false if it wasn't possible to queue it. |