diff options
| author | Christoffer Dall <cdall@linaro.org> | 2016-10-16 22:19:11 +0200 |
|---|---|---|
| committer | Christoffer Dall <christoffer.dall@linaro.org> | 2017-11-06 16:23:10 +0100 |
| commit | 006df0f34930e18d0aa52f05705bdfe1fc565943 (patch) | |
| tree | 97d97e06b56113a033ed63ce7ad16096779804f5 /virt/kvm/arm/vgic/vgic-v3.c | |
| parent | KVM: arm/arm64: Guard kvm_vgic_map_is_active against !vgic_initialized (diff) | |
| download | linux-006df0f34930e18d0aa52f05705bdfe1fc565943.tar.xz linux-006df0f34930e18d0aa52f05705bdfe1fc565943.zip | |
KVM: arm/arm64: Support calling vgic_update_irq_pending from irq context
We are about to optimize our timer handling logic which involves
injecting irqs to the vgic directly from the irq handler.
Unfortunately, the injection path can take any AP list lock and irq lock
and we must therefore make sure to use spin_lock_irqsave where ever
interrupts are enabled and we are taking any of those locks, to avoid
deadlocking between process context and the ISR.
This changes a lot of the VGIC code, but the good news are that the
changes are mostly mechanical.
Acked-by: Marc Zyngier <marc,zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-v3.c')
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-v3.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index 96ea597db0e7..863351c090d8 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -44,6 +44,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu) struct vgic_v3_cpu_if *cpuif = &vgic_cpu->vgic_v3; u32 model = vcpu->kvm->arch.vgic.vgic_model; int lr; + unsigned long flags; cpuif->vgic_hcr &= ~ICH_HCR_UIE; @@ -66,7 +67,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu) if (!irq) /* An LPI could have been unmapped. */ continue; - spin_lock(&irq->irq_lock); + spin_lock_irqsave(&irq->irq_lock, flags); /* Always preserve the active bit */ irq->active = !!(val & ICH_LR_ACTIVE_BIT); @@ -94,7 +95,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu) irq->pending_latch = false; } - spin_unlock(&irq->irq_lock); + spin_unlock_irqrestore(&irq->irq_lock, flags); vgic_put_irq(vcpu->kvm, irq); } @@ -278,6 +279,7 @@ int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq) bool status; u8 val; int ret; + unsigned long flags; retry: vcpu = irq->target_vcpu; @@ -296,13 +298,13 @@ retry: status = val & (1 << bit_nr); - spin_lock(&irq->irq_lock); + spin_lock_irqsave(&irq->irq_lock, flags); if (irq->target_vcpu != vcpu) { - spin_unlock(&irq->irq_lock); + spin_unlock_irqrestore(&irq->irq_lock, flags); goto retry; } irq->pending_latch = status; - vgic_queue_irq_unlock(vcpu->kvm, irq); + vgic_queue_irq_unlock(vcpu->kvm, irq, flags); if (status) { /* clear consumed data */ |