KVM: arm/arm64: vgic: Make vgic_irq->irq_lock a raw_spinlock

vgic_irq->irq_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 <julien.thierry@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>

1 files changed, 35 insertions, 36 deletions

diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index 870b1185173b..bc36f2e68f5a 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -244,8 +244,8 @@ static int vgic_irq_cmp(void *priv, struct list_head *a, struct list_head *b)
 	bool penda, pendb;
 	int ret;
 
-	spin_lock(&irqa->irq_lock);
-	spin_lock_nested(&irqb->irq_lock, SINGLE_DEPTH_NESTING);
+	raw_spin_lock(&irqa->irq_lock);
+	raw_spin_lock_nested(&irqb->irq_lock, SINGLE_DEPTH_NESTING);
 
 	if (irqa->active || irqb->active) {
 		ret = (int)irqb->active - (int)irqa->active;
@@ -263,8 +263,8 @@ static int vgic_irq_cmp(void *priv, struct list_head *a, struct list_head *b)
 	/* Both pending and enabled, sort by priority */
 	ret = irqa->priority - irqb->priority;
 out:
-	spin_unlock(&irqb->irq_lock);
-	spin_unlock(&irqa->irq_lock);
+	raw_spin_unlock(&irqb->irq_lock);
+	raw_spin_unlock(&irqa->irq_lock);
 	return ret;
 }
 
@@ -325,7 +325,7 @@ retry:
 		 * not need to be inserted into an ap_list and there is also
 		 * no more work for us to do.
 		 */
-		spin_unlock_irqrestore(&irq->irq_lock, flags);
+		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 
 		/*
 		 * We have to kick the VCPU here, because we could be
@@ -347,12 +347,12 @@ retry:
 	 * We must unlock the irq lock to take the ap_list_lock where
 	 * we are going to insert this new pending interrupt.
 	 */
-	spin_unlock_irqrestore(&irq->irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 
 	/* someone can do stuff here, which we re-check below */
 
 	spin_lock_irqsave(&vcpu->arch.vgic_cpu.ap_list_lock, flags);
-	spin_lock(&irq->irq_lock);
+	raw_spin_lock(&irq->irq_lock);
 
 	/*
 	 * Did something change behind our backs?
@@ -367,10 +367,10 @@ retry:
 	 */
 
 	if (unlikely(irq->vcpu || vcpu != vgic_target_oracle(irq))) {
-		spin_unlock(&irq->irq_lock);
+		raw_spin_unlock(&irq->irq_lock);
 		spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags);
 
-		spin_lock_irqsave(&irq->irq_lock, flags);
+		raw_spin_lock_irqsave(&irq->irq_lock, flags);
 		goto retry;
 	}
 
@@ -382,7 +382,7 @@ retry:
 	list_add_tail(&irq->ap_list, &vcpu->arch.vgic_cpu.ap_list_head);
 	irq->vcpu = vcpu;
 
-	spin_unlock(&irq->irq_lock);
+	raw_spin_unlock(&irq->irq_lock);
 	spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags);
 
 	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
@@ -430,11 +430,11 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
 	if (!irq)
 		return -EINVAL;
 
-	spin_lock_irqsave(&irq->irq_lock, flags);
+	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 
 	if (!vgic_validate_injection(irq, level, owner)) {
 		/* Nothing to see here, move along... */
-		spin_unlock_irqrestore(&irq->irq_lock, flags);
+		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 		vgic_put_irq(kvm, irq);
 		return 0;
 	}
@@ -494,9 +494,9 @@ int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq,
 
 	BUG_ON(!irq);
 
-	spin_lock_irqsave(&irq->irq_lock, flags);
+	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 	ret = kvm_vgic_map_irq(vcpu, irq, host_irq, get_input_level);
-	spin_unlock_irqrestore(&irq->irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 	vgic_put_irq(vcpu->kvm, irq);
 
 	return ret;
@@ -519,11 +519,11 @@ void kvm_vgic_reset_mapped_irq(struct kvm_vcpu *vcpu, u32 vintid)
 	if (!irq->hw)
 		goto out;
 
-	spin_lock_irqsave(&irq->irq_lock, flags);
+	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 	irq->active = false;
 	irq->pending_latch = false;
 	irq->line_level = false;
-	spin_unlock_irqrestore(&irq->irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 out:
 	vgic_put_irq(vcpu->kvm, irq);
 }
@@ -539,9 +539,9 @@ int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid)
 	irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
 	BUG_ON(!irq);
 
-	spin_lock_irqsave(&irq->irq_lock, flags);
+	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 	kvm_vgic_unmap_irq(irq);
-	spin_unlock_irqrestore(&irq->irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 	vgic_put_irq(vcpu->kvm, irq);
 
 	return 0;
@@ -571,12 +571,12 @@ int kvm_vgic_set_owner(struct kvm_vcpu *vcpu, unsigned int intid, void *owner)
 		return -EINVAL;
 
 	irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
-	spin_lock_irqsave(&irq->irq_lock, flags);
+	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 	if (irq->owner && irq->owner != owner)
 		ret = -EEXIST;
 	else
 		irq->owner = owner;
-	spin_unlock_irqrestore(&irq->irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 
 	return ret;
 }
@@ -603,7 +603,7 @@ retry:
 		struct kvm_vcpu *target_vcpu, *vcpuA, *vcpuB;
 		bool target_vcpu_needs_kick = false;
 
-		spin_lock(&irq->irq_lock);
+		raw_spin_lock(&irq->irq_lock);
 
 		BUG_ON(vcpu != irq->vcpu);
 
@@ -616,7 +616,7 @@ retry:
 			 */
 			list_del(&irq->ap_list);
 			irq->vcpu = NULL;
-			spin_unlock(&irq->irq_lock);
+			raw_spin_unlock(&irq->irq_lock);
 
 			/*
 			 * This vgic_put_irq call matches the
@@ -631,13 +631,13 @@ retry:
 
 		if (target_vcpu == vcpu) {
 			/* We're on the right CPU */
-			spin_unlock(&irq->irq_lock);
+			raw_spin_unlock(&irq->irq_lock);
 			continue;
 		}
 
 		/* This interrupt looks like it has to be migrated. */
 
-		spin_unlock(&irq->irq_lock);
+		raw_spin_unlock(&irq->irq_lock);
 		spin_unlock(&vgic_cpu->ap_list_lock);
 
 		/*
@@ -655,7 +655,7 @@ retry:
 		spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock);
 		spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock,
 				 SINGLE_DEPTH_NESTING);
-		spin_lock(&irq->irq_lock);
+		raw_spin_lock(&irq->irq_lock);
 
 		/*
 		 * If the affinity has been preserved, move the
@@ -675,7 +675,7 @@ retry:
 			target_vcpu_needs_kick = true;
 		}
 
-		spin_unlock(&irq->irq_lock);
+		raw_spin_unlock(&irq->irq_lock);
 		spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock);
 		spin_unlock(&vcpuA->arch.vgic_cpu.ap_list_lock);
 
@@ -741,10 +741,10 @@ static int compute_ap_list_depth(struct kvm_vcpu *vcpu,
 	list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) {
 		int w;
 
-		spin_lock(&irq->irq_lock);
+		raw_spin_lock(&irq->irq_lock);
 		/* GICv2 SGIs can count for more than one... */
 		w = vgic_irq_get_lr_count(irq);
-		spin_unlock(&irq->irq_lock);
+		raw_spin_unlock(&irq->irq_lock);
 
 		count += w;
 		*multi_sgi |= (w > 1);
@@ -770,7 +770,7 @@ static void vgic_flush_lr_state(struct kvm_vcpu *vcpu)
 	count = 0;
 
 	list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) {
-		spin_lock(&irq->irq_lock);
+		raw_spin_lock(&irq->irq_lock);
 
 		/*
 		 * If we have multi-SGIs in the pipeline, we need to
@@ -780,7 +780,7 @@ static void vgic_flush_lr_state(struct kvm_vcpu *vcpu)
 		 * the AP list has been sorted already.
 		 */
 		if (multi_sgi && irq->priority > prio) {
-			spin_unlock(&irq->irq_lock);
+			_raw_spin_unlock(&irq->irq_lock);
 			break;
 		}
 
@@ -791,7 +791,7 @@ static void vgic_flush_lr_state(struct kvm_vcpu *vcpu)
 				prio = irq->priority;
 		}
 
-		spin_unlock(&irq->irq_lock);
+		raw_spin_unlock(&irq->irq_lock);
 
 		if (count == kvm_vgic_global_state.nr_lr) {
 			if (!list_is_last(&irq->ap_list,
@@ -921,11 +921,11 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 	spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags);
 
 	list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) {
-		spin_lock(&irq->irq_lock);
+		raw_spin_lock(&irq->irq_lock);
 		pending = irq_is_pending(irq) && irq->enabled &&
 			  !irq->active &&
 			  irq->priority < vmcr.pmr;
-		spin_unlock(&irq->irq_lock);
+		raw_spin_unlock(&irq->irq_lock);
 
 		if (pending)
 			break;
@@ -963,11 +963,10 @@ bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid)
 		return false;
 
 	irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
-	spin_lock_irqsave(&irq->irq_lock, flags);
+	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 	map_is_active = irq->hw && irq->active;
-	spin_unlock_irqrestore(&irq->irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 	vgic_put_irq(vcpu->kvm, irq);
 
 	return map_is_active;
 }
-