[PULL 28/28] KVM: arm/arm64: Fixup userspace irqchip static key optimization
Christoffer Dall
christoffer.dall at linaro.org
Wed Jan 31 01:35:07 PST 2018
When I introduced a static key to avoid work in the critical path for
userspace irqchips which is very rarely used, I accidentally messed up
my logic and used && where I should have used ||, because the point was
to short-circuit the evaluation in case userspace irqchips weren't even
in use.
This fixes an issue when running in-kernel irqchip VMs alongside
userspace irqchip VMs.
Acked-by: Marc Zyngier <marc.zyngier at arm.com>
Fixes: c44c232ee2d3 ("KVM: arm/arm64: Avoid work when userspace iqchips are not used")
Signed-off-by: Christoffer Dall <christoffer.dall at linaro.org>
---
virt/kvm/arm/arch_timer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 63cf828f3c4f..fb6bd9b9845e 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -286,7 +286,7 @@ static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
trace_kvm_timer_update_irq(vcpu->vcpu_id, timer_ctx->irq.irq,
timer_ctx->irq.level);
- if (!static_branch_unlikely(&userspace_irqchip_in_use) &&
+ if (!static_branch_unlikely(&userspace_irqchip_in_use) ||
likely(irqchip_in_kernel(vcpu->kvm))) {
ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
timer_ctx->irq.irq,
--
2.14.2
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