From e08d8d296079e8fd7eefd53f73dcafebd3a5bf9f Mon Sep 17 00:00:00 2001 From: Julien Thierry Date: Mon, 7 Jan 2019 15:06:17 +0000 Subject: [PATCH] KVM: arm/arm64: vgic: Make vgic_cpu->ap_list_lock a raw_spinlock vgic_cpu->ap_list_lock must always be taken with interrupts disabled as it is used in interrupt context. For configurations such as PREEMPT_RT_FULL, this means that it should be a raw_spinlock since RT spinlocks are interruptible. Signed-off-by: Julien Thierry Acked-by: Christoffer Dall Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- include/kvm/arm_vgic.h | 2 +- virt/kvm/arm/vgic/vgic-init.c | 2 +- virt/kvm/arm/vgic/vgic.c | 37 ++++++++++++++++++----------------- 3 files changed, 21 insertions(+), 20 deletions(-) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 32954e115796..c36c86f1ec9a 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -307,7 +307,7 @@ struct vgic_cpu { unsigned int used_lrs; struct vgic_irq private_irqs[VGIC_NR_PRIVATE_IRQS]; - spinlock_t ap_list_lock; /* Protects the ap_list */ + raw_spinlock_t ap_list_lock; /* Protects the ap_list */ /* * List of IRQs that this VCPU should consider because they are either diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c index 330c1ada7326..dfbfcb1fe933 100644 --- a/virt/kvm/arm/vgic/vgic-init.c +++ b/virt/kvm/arm/vgic/vgic-init.c @@ -206,7 +206,7 @@ int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) vgic_cpu->sgi_iodev.base_addr = VGIC_ADDR_UNDEF; INIT_LIST_HEAD(&vgic_cpu->ap_list_head); - spin_lock_init(&vgic_cpu->ap_list_lock); + raw_spin_lock_init(&vgic_cpu->ap_list_lock); /* * Enable and configure all SGIs to be edge-triggered and diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c index ea54a1923c4f..abd9c7352677 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -54,11 +54,11 @@ struct vgic_global kvm_vgic_global_state __ro_after_init = { * When taking more than one ap_list_lock at the same time, always take the * lowest numbered VCPU's ap_list_lock first, so: * vcpuX->vcpu_id < vcpuY->vcpu_id: - * spin_lock(vcpuX->arch.vgic_cpu.ap_list_lock); - * spin_lock(vcpuY->arch.vgic_cpu.ap_list_lock); + * raw_spin_lock(vcpuX->arch.vgic_cpu.ap_list_lock); + * raw_spin_lock(vcpuY->arch.vgic_cpu.ap_list_lock); * * Since the VGIC must support injecting virtual interrupts from ISRs, we have - * to use the spin_lock_irqsave/spin_unlock_irqrestore versions of outer + * to use the raw_spin_lock_irqsave/raw_spin_unlock_irqrestore versions of outer * spinlocks for any lock that may be taken while injecting an interrupt. */ @@ -351,7 +351,7 @@ bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq, /* someone can do stuff here, which we re-check below */ - spin_lock_irqsave(&vcpu->arch.vgic_cpu.ap_list_lock, flags); + raw_spin_lock_irqsave(&vcpu->arch.vgic_cpu.ap_list_lock, flags); raw_spin_lock(&irq->irq_lock); /* @@ -368,7 +368,8 @@ bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq, if (unlikely(irq->vcpu || vcpu != vgic_target_oracle(irq))) { raw_spin_unlock(&irq->irq_lock); - spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags); + raw_spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, + flags); raw_spin_lock_irqsave(&irq->irq_lock, flags); goto retry; @@ -383,7 +384,7 @@ bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq, irq->vcpu = vcpu; raw_spin_unlock(&irq->irq_lock); - spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags); + raw_spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags); kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); kvm_vcpu_kick(vcpu); @@ -597,7 +598,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu) DEBUG_SPINLOCK_BUG_ON(!irqs_disabled()); retry: - spin_lock(&vgic_cpu->ap_list_lock); + raw_spin_lock(&vgic_cpu->ap_list_lock); list_for_each_entry_safe(irq, tmp, &vgic_cpu->ap_list_head, ap_list) { struct kvm_vcpu *target_vcpu, *vcpuA, *vcpuB; @@ -638,7 +639,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu) /* This interrupt looks like it has to be migrated. */ raw_spin_unlock(&irq->irq_lock); - spin_unlock(&vgic_cpu->ap_list_lock); + raw_spin_unlock(&vgic_cpu->ap_list_lock); /* * Ensure locking order by always locking the smallest @@ -652,9 +653,9 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu) vcpuB = vcpu; } - spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock); - spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock, - SINGLE_DEPTH_NESTING); + raw_spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock); + raw_spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock, + SINGLE_DEPTH_NESTING); raw_spin_lock(&irq->irq_lock); /* @@ -676,8 +677,8 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu) } raw_spin_unlock(&irq->irq_lock); - spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock); - spin_unlock(&vcpuA->arch.vgic_cpu.ap_list_lock); + raw_spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock); + raw_spin_unlock(&vcpuA->arch.vgic_cpu.ap_list_lock); if (target_vcpu_needs_kick) { kvm_make_request(KVM_REQ_IRQ_PENDING, target_vcpu); @@ -687,7 +688,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu) goto retry; } - spin_unlock(&vgic_cpu->ap_list_lock); + raw_spin_unlock(&vgic_cpu->ap_list_lock); } static inline void vgic_fold_lr_state(struct kvm_vcpu *vcpu) @@ -872,9 +873,9 @@ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) DEBUG_SPINLOCK_BUG_ON(!irqs_disabled()); - spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); + raw_spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); vgic_flush_lr_state(vcpu); - spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); + raw_spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); if (can_access_vgic_from_kernel()) vgic_restore_state(vcpu); @@ -918,7 +919,7 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) vgic_get_vmcr(vcpu, &vmcr); - spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags); + raw_spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags); list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) { raw_spin_lock(&irq->irq_lock); @@ -931,7 +932,7 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) break; } - spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags); + raw_spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags); return pending; }