KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interrupt

commit ddf42d068f8802de122bb7efdfcb3179336053f1 upstream.

When an interrupt is injected with the HW bit set (indicating that
deactivation should be propagated to the physical distributor),
special care must be taken so that we never mark the corresponding
LR with the Active+Pending state (as the pending state is kept in
the physycal distributor).

Cc: stable@vger.kernel.org
Fixes: 140b086dd197 ("KVM: arm/arm64: vgic-new: Add GICv2 world switch backend")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index 834137e..1ab58f7 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -168,6 +168,13 @@ void vgic_v2_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
        if (irq->hw) {
                val |= GICH_LR_HW;
                val |= irq->hwintid << GICH_LR_PHYSID_CPUID_SHIFT;
+               /*
+                * Never set pending+active on a HW interrupt, as the
+                * pending state is kept at the physical distributor
+                * level.
+                */
+               if (irq->active && irq->pending)
+                       val &= ~GICH_LR_PENDING_BIT;
        } else {
                if (irq->config == VGIC_CONFIG_LEVEL)
                        val |= GICH_LR_EOI;