On Sat, Dec 13 2014 at 11:17:28 AM, Christoffer Dall <[email protected]> wrote: > Userspace assumes that it can wire up IRQ injections after having > created all VCPUs and after having created the VGIC, but potentially > before starting the first VCPU. This can currently lead to lost IRQs > because the state of that IRQ injection is not stored anywhere and we > don't return an error to userspace. > > We haven't seen this problem manifest itself yet, presumably because > guests reset the devices on boot, but this could cause issues with > migration and other non-standard startup configurations. > > Signed-off-by: Christoffer Dall <[email protected]> > --- > virt/kvm/arm/vgic.c | 17 ++++++++++++++--- > 1 file changed, 14 insertions(+), 3 deletions(-) > > diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c > index e1bef68..330445c 100644 > --- a/virt/kvm/arm/vgic.c > +++ b/virt/kvm/arm/vgic.c > @@ -1693,11 +1693,22 @@ out: > int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, > bool level) > { > - if (likely(vgic_ready(kvm)) && > - vgic_update_irq_pending(kvm, cpuid, irq_num, level)) > + int ret = 0; > + > + if (unlikely(!vgic_initialized(kvm))) { > + mutex_lock(&kvm->lock); > + ret = vgic_init(kvm); > + mutex_unlock(&kvm->lock); > + > + if (ret) > + goto out; > + } > + > + if (vgic_update_irq_pending(kvm, cpuid, irq_num, level)) > vgic_kick_vcpus(kvm); > > - return 0; > +out: > + return ret; > } > > static irqreturn_t vgic_maintenance_handler(int irq, void *data)
Reviewed-by: Marc Zyngier <[email protected]> M. -- Jazz is not dead. It just smells funny. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
