From cf9eeac46350b8b43730b7dc5e999757bed089a4 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Wed, 14 Mar 2012 11:02:11 +0100 Subject: KVM: Convert intx_mask_lock to spin lock As kvm_notify_acked_irq calls kvm_assigned_dev_ack_irq under rcu_read_lock, we cannot use a mutex in the latter function. Switch to a spin lock to address this. Signed-off-by: Jan Kiszka Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- include/linux/kvm_host.h | 2 +- virt/kvm/assigned-dev.c | 14 +++++++------- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ec171c1d0878..40bb1c661a6e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -556,7 +556,7 @@ struct kvm_assigned_dev_kernel { struct pci_dev *dev; struct kvm *kvm; spinlock_t intx_lock; - struct mutex intx_mask_lock; + spinlock_t intx_mask_lock; char irq_name[32]; struct pci_saved_state *pci_saved_state; }; diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c index 08e05715df72..01f572c10c71 100644 --- a/virt/kvm/assigned-dev.c +++ b/virt/kvm/assigned-dev.c @@ -77,11 +77,11 @@ kvm_assigned_dev_raise_guest_irq(struct kvm_assigned_dev_kernel *assigned_dev, { if (unlikely(assigned_dev->irq_requested_type & KVM_DEV_IRQ_GUEST_INTX)) { - mutex_lock(&assigned_dev->intx_mask_lock); + spin_lock(&assigned_dev->intx_mask_lock); if (!(assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX)) kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id, vector, 1); - mutex_unlock(&assigned_dev->intx_mask_lock); + spin_unlock(&assigned_dev->intx_mask_lock); } else kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id, vector, 1); @@ -141,7 +141,7 @@ static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian) kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0); - mutex_lock(&dev->intx_mask_lock); + spin_lock(&dev->intx_mask_lock); if (!(dev->flags & KVM_DEV_ASSIGN_MASK_INTX)) { bool reassert = false; @@ -165,7 +165,7 @@ static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian) dev->guest_irq, 1); } - mutex_unlock(&dev->intx_mask_lock); + spin_unlock(&dev->intx_mask_lock); } static void deassign_guest_irq(struct kvm *kvm, @@ -707,7 +707,7 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm, match->flags = assigned_dev->flags; match->dev = dev; spin_lock_init(&match->intx_lock); - mutex_init(&match->intx_mask_lock); + spin_lock_init(&match->intx_mask_lock); match->irq_source_id = -1; match->kvm = kvm; match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq; @@ -868,7 +868,7 @@ static int kvm_vm_ioctl_set_pci_irq_mask(struct kvm *kvm, goto out; } - mutex_lock(&match->intx_mask_lock); + spin_lock(&match->intx_mask_lock); match->flags &= ~KVM_DEV_ASSIGN_MASK_INTX; match->flags |= assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX; @@ -895,7 +895,7 @@ static int kvm_vm_ioctl_set_pci_irq_mask(struct kvm *kvm, } } - mutex_unlock(&match->intx_mask_lock); + spin_unlock(&match->intx_mask_lock); out: mutex_unlock(&kvm->lock); -- cgit v1.2.3