| Message ID | 20130507130706.21663153@gondolin (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 07, 2013 at 01:07:06PM +0200, Cornelia Huck wrote: > On Tue, 7 May 2013 11:21:09 +0200 > Cornelia Huck <cornelia.huck@de.ibm.com> wrote: > > > On Tue, 7 May 2013 12:12:09 +0300 > > Gleb Natapov <gleb@redhat.com> wrote: > > > > > On Tue, May 07, 2013 at 05:10:41PM +0800, Asias He wrote: > > > > On Tue, May 07, 2013 at 11:42:07AM +0300, Gleb Natapov wrote: > > > > > On Tue, May 07, 2013 at 04:36:50PM +0800, Asias He wrote: > > > > > > On Tue, May 07, 2013 at 11:18:38AM +0300, Gleb Natapov wrote: > > > > > > > On Tue, May 07, 2013 at 04:14:50PM +0800, Asias He wrote: > > > > > > > > On Tue, May 07, 2013 at 10:55:36AM +0300, Gleb Natapov wrote: > > > > > > > > > On Tue, May 07, 2013 at 09:37:30AM +0800, Asias He wrote: > > > > > > > > > > Hi, > > > > > > > > > > > > > > > > > > > > I am seeing this with linus/master. Any ideas? > > > > > > > > > > > > > > > > > > > How reproducible it this? What HEAD are you seeing this with? > > > > > > > > > > > > > > > > Almost always. Start a guest with vhost-net on. > > > > > > > > > > > > > > > It happens during start or on VM exit? The trace shows do_exit() > > > > > > > > > > > > > > > QEMU : e3351000cd682200835763caca87adf708ed1c65 > > > > > > > > KERNEL: 51a26ae7a14b85c99c9be470c2d28eeeba0f26a3 > > > > > > > > > > > > > > > Can you try with kvm.git next branch? > > > > > > > > > > > > With next branch db6ae6158186a17165ef990bda2895ae7594b039, > > > > > > > > > > > Can you revert a0f155e9646d5f1c263f6f9aae880151100243bb and try again? > > > > > > > > The issue is gone with a0f155e9646d5f1c263f6f9aae880151100243bb > > > > reverted. > > > > > > > Cornelia, any ideas? > > > > irqfd_deactivate before kvm_init or after kvm_exit? Let me look... > > > > Hm, no idea. > For am quick look is seems that after the patch irqfd_cleanup_wq is initialized as part of kvm-intel/kvm-amd module, but before the patch is was initialized as part of kvm module. The later is how it should be, but I do not see why would it cause the problem. > Asias, could you try whether the patch below yields any interesting > backtraces? > > diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c > index 64ee720..59c3810 100644 > --- a/virt/kvm/eventfd.c > +++ b/virt/kvm/eventfd.c > @@ -92,6 +92,8 @@ struct _irqfd { > }; > > static struct workqueue_struct *irqfd_cleanup_wq; > +static int irqfd_ready; > +static unsigned long irqfd_cnt; > > static void > irqfd_inject(struct work_struct *work) > @@ -410,6 +412,8 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) > */ > fput(file); > > + irqfd_cnt++; > + > return 0; > > fail: > @@ -483,12 +487,16 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd *args) > */ > flush_workqueue(irqfd_cleanup_wq); > > + irqfd_cnt--; > + > return 0; > } > > int > kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args) > { > + WARN_ON(!irqfd_ready); > + > if (args->flags & ~(KVM_IRQFD_FLAG_DEASSIGN | KVM_IRQFD_FLAG_RESAMPLE)) > return -EINVAL; > > @@ -548,15 +556,22 @@ void kvm_irq_routing_update(struct kvm *kvm, > */ > int kvm_irqfd_init(void) > { > + WARN_ON(irqfd_cnt); > + > irqfd_cleanup_wq = create_singlethread_workqueue("kvm-irqfd-cleanup"); > if (!irqfd_cleanup_wq) > return -ENOMEM; > > + irqfd_ready = 1; > + > return 0; > } > > void kvm_irqfd_exit(void) > { > + WARN_ON(irqfd_cnt); > + irqfd_ready = 0; > + > destroy_workqueue(irqfd_cleanup_wq); > } > #endif -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, May 07, 2013 at 05:29:09PM +0300, Gleb Natapov wrote: > On Tue, May 07, 2013 at 01:07:06PM +0200, Cornelia Huck wrote: > > On Tue, 7 May 2013 11:21:09 +0200 > > Cornelia Huck <cornelia.huck@de.ibm.com> wrote: > > > > > On Tue, 7 May 2013 12:12:09 +0300 > > > Gleb Natapov <gleb@redhat.com> wrote: > > > > > > > On Tue, May 07, 2013 at 05:10:41PM +0800, Asias He wrote: > > > > > On Tue, May 07, 2013 at 11:42:07AM +0300, Gleb Natapov wrote: > > > > > > On Tue, May 07, 2013 at 04:36:50PM +0800, Asias He wrote: > > > > > > > On Tue, May 07, 2013 at 11:18:38AM +0300, Gleb Natapov wrote: > > > > > > > > On Tue, May 07, 2013 at 04:14:50PM +0800, Asias He wrote: > > > > > > > > > On Tue, May 07, 2013 at 10:55:36AM +0300, Gleb Natapov wrote: > > > > > > > > > > On Tue, May 07, 2013 at 09:37:30AM +0800, Asias He wrote: > > > > > > > > > > > Hi, > > > > > > > > > > > > > > > > > > > > > > I am seeing this with linus/master. Any ideas? > > > > > > > > > > > > > > > > > > > > > How reproducible it this? What HEAD are you seeing this with? > > > > > > > > > > > > > > > > > > Almost always. Start a guest with vhost-net on. > > > > > > > > > > > > > > > > > It happens during start or on VM exit? The trace shows do_exit() > > > > > > > > > > > > > > > > > QEMU : e3351000cd682200835763caca87adf708ed1c65 > > > > > > > > > KERNEL: 51a26ae7a14b85c99c9be470c2d28eeeba0f26a3 > > > > > > > > > > > > > > > > > Can you try with kvm.git next branch? > > > > > > > > > > > > > > With next branch db6ae6158186a17165ef990bda2895ae7594b039, > > > > > > > > > > > > > Can you revert a0f155e9646d5f1c263f6f9aae880151100243bb and try again? > > > > > > > > > > The issue is gone with a0f155e9646d5f1c263f6f9aae880151100243bb > > > > > reverted. > > > > > > > > > Cornelia, any ideas? > > > > > > irqfd_deactivate before kvm_init or after kvm_exit? Let me look... > > > > > > > Hm, no idea. > > > For am quick look is seems that after the patch irqfd_cleanup_wq is > initialized as part of kvm-intel/kvm-amd module, but before the patch is > was initialized as part of kvm module. The later is how it should be, > but I do not see why would it cause the problem. I have a fix for this now. Will send out patch shortly. > > Asias, could you try whether the patch below yields any interesting > > backtraces? > > > > diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c > > index 64ee720..59c3810 100644 > > --- a/virt/kvm/eventfd.c > > +++ b/virt/kvm/eventfd.c > > @@ -92,6 +92,8 @@ struct _irqfd { > > }; > > > > static struct workqueue_struct *irqfd_cleanup_wq; > > +static int irqfd_ready; > > +static unsigned long irqfd_cnt; > > > > static void > > irqfd_inject(struct work_struct *work) > > @@ -410,6 +412,8 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) > > */ > > fput(file); > > > > + irqfd_cnt++; > > + > > return 0; > > > > fail: > > @@ -483,12 +487,16 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd *args) > > */ > > flush_workqueue(irqfd_cleanup_wq); > > > > + irqfd_cnt--; > > + > > return 0; > > } > > > > int > > kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args) > > { > > + WARN_ON(!irqfd_ready); > > + > > if (args->flags & ~(KVM_IRQFD_FLAG_DEASSIGN | KVM_IRQFD_FLAG_RESAMPLE)) > > return -EINVAL; > > > > @@ -548,15 +556,22 @@ void kvm_irq_routing_update(struct kvm *kvm, > > */ > > int kvm_irqfd_init(void) > > { > > + WARN_ON(irqfd_cnt); > > + > > irqfd_cleanup_wq = create_singlethread_workqueue("kvm-irqfd-cleanup"); > > if (!irqfd_cleanup_wq) > > return -ENOMEM; > > > > + irqfd_ready = 1; > > + > > return 0; > > } > > > > void kvm_irqfd_exit(void) > > { > > + WARN_ON(irqfd_cnt); > > + irqfd_ready = 0; > > + > > destroy_workqueue(irqfd_cleanup_wq); > > } > > #endif > > -- > Gleb.
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index 64ee720..59c3810 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -92,6 +92,8 @@ struct _irqfd { }; static struct workqueue_struct *irqfd_cleanup_wq; +static int irqfd_ready; +static unsigned long irqfd_cnt; static void irqfd_inject(struct work_struct *work) @@ -410,6 +412,8 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) */ fput(file); + irqfd_cnt++; + return 0; fail: @@ -483,12 +487,16 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd *args) */ flush_workqueue(irqfd_cleanup_wq); + irqfd_cnt--; + return 0; } int kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args) { + WARN_ON(!irqfd_ready); + if (args->flags & ~(KVM_IRQFD_FLAG_DEASSIGN | KVM_IRQFD_FLAG_RESAMPLE)) return -EINVAL; @@ -548,15 +556,22 @@ void kvm_irq_routing_update(struct kvm *kvm, */ int kvm_irqfd_init(void) { + WARN_ON(irqfd_cnt); + irqfd_cleanup_wq = create_singlethread_workqueue("kvm-irqfd-cleanup"); if (!irqfd_cleanup_wq) return -ENOMEM; + irqfd_ready = 1; + return 0; } void kvm_irqfd_exit(void) { + WARN_ON(irqfd_cnt); + irqfd_ready = 0; + destroy_workqueue(irqfd_cleanup_wq); } #endif