summaryrefslogtreecommitdiff
path: root/virt
diff options
context:
space:
mode:
authorMarc Zyngier <marc.zyngier@arm.com>2017-11-30 17:00:30 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-02-25 11:07:56 +0100
commit97ef3a5027b043bcb6a9c4aeefdcbfe4cf6221f7 (patch)
tree85d8ea28a08d5b046c68c7f6ed881c5af9bfd905 /virt
parent2117bba3cfbb120dee072a11aba4a116f316dff5 (diff)
KVM: arm/arm64: Fix spinlock acquisition in vgic_set_owner
[ Upstream commit 7465894e90e5a47e0e52aa5f1f708653fc40020f ] vgic_set_owner acquires the irq lock without disabling interrupts, resulting in a lockdep splat (an interrupt could fire and result in the same lock being taken if the same virtual irq is to be injected). In practice, it is almost impossible to trigger this bug, but better safe than sorry. Convert the lock acquisition to a spin_lock_irqsave() and keep lockdep happy. Reported-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'virt')
-rw-r--r--virt/kvm/arm/vgic/vgic.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index fed717e07938..da53c6e7d688 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -454,6 +454,7 @@ int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int virt_irq)
int kvm_vgic_set_owner(struct kvm_vcpu *vcpu, unsigned int intid, void *owner)
{
struct vgic_irq *irq;
+ unsigned long flags;
int ret = 0;
if (!vgic_initialized(vcpu->kvm))
@@ -464,12 +465,12 @@ 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(&irq->irq_lock);
+ spin_lock_irqsave(&irq->irq_lock, flags);
if (irq->owner && irq->owner != owner)
ret = -EEXIST;
else
irq->owner = owner;
- spin_unlock(&irq->irq_lock);
+ spin_unlock_irqrestore(&irq->irq_lock, flags);
return ret;
}