Hi Feng, On 07/06/2015 09:55 AM, Wu, Feng wrote: > > >> -----Original Message----- >> From: Eric Auger [mailto:eric.au...@linaro.org] >> Sent: Thursday, July 02, 2015 9:17 PM >> To: eric.au...@st.com; eric.au...@linaro.org; >> linux-arm-ker...@lists.infradead.org; kvm...@lists.cs.columbia.edu; >> k...@vger.kernel.org; christoffer.d...@linaro.org; marc.zyng...@arm.com; >> alex.william...@redhat.com; pbonz...@redhat.com; avi.kiv...@gmail.com; >> mtosa...@redhat.com; Wu, Feng; j...@8bytes.org; >> b.rey...@virtualopensystems.com >> Cc: linux-kernel@vger.kernel.org; patc...@linaro.org >> Subject: [RFC 16/17] KVM: eventfd: add irq bypass consumer management >> >> This patch adds the registration/unregistration of an >> irq_bypass_consumer on irqfd assignment/deassignment. >> >> Signed-off-by: Eric Auger <eric.au...@linaro.org> >> --- >> virt/kvm/eventfd.c | 22 +++++++++++++++++++--- >> 1 file changed, 19 insertions(+), 3 deletions(-) >> >> diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c >> index f3da161..425a47b 100644 >> --- a/virt/kvm/eventfd.c >> +++ b/virt/kvm/eventfd.c >> @@ -34,6 +34,7 @@ >> #include <linux/srcu.h> >> #include <linux/slab.h> >> #include <linux/seqlock.h> >> +#include <linux/irqbypass.h> >> #include <trace/events/kvm.h> >> >> #include <kvm/iodev.h> >> @@ -93,6 +94,7 @@ struct _irqfd { >> struct list_head list; >> poll_table pt; >> struct work_struct shutdown; >> + struct irq_bypass_consumer *cons; >> }; >> >> static struct workqueue_struct *irqfd_cleanup_wq; >> @@ -429,7 +431,21 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd >> *args) >> */ >> fdput(f); >> >> - /* irq_bypass_register_consumer(); */ >> + irqfd->cons = kzalloc(sizeof(struct irq_bypass_consumer), >> + GFP_KERNEL); >> + if (!irqfd->cons) { >> + ret = -ENOMEM; >> + goto fail; >> + } >> + irqfd->cons->token = (void *)irqfd->eventfd; >> + irqfd->cons->gsi = irqfd->gsi; >> + irqfd->cons->kvm = kvm; >> + irqfd->cons->add_producer = kvm_arch_add_producer; >> + irqfd->cons->del_producer = kvm_arch_del_producer; >> + irqfd->cons->stop_consumer = kvm_arch_stop_consumer; >> + irqfd->cons->resume_consumer = kvm_arch_resume_consumer; >> + ret = irq_bypass_register_consumer(irqfd->cons); >> + WARN_ON(ret); >> >> return 0; >> >> @@ -530,8 +546,6 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd >> *args) >> struct _irqfd *irqfd, *tmp; >> struct eventfd_ctx *eventfd; >> >> - /* irq_bypass_unregister_consumer() */ >> - >> eventfd = eventfd_ctx_fdget(args->fd); >> if (IS_ERR(eventfd)) >> return PTR_ERR(eventfd); >> @@ -550,6 +564,8 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd >> *args) >> irqfd->irq_entry.type = 0; >> write_seqcount_end(&irqfd->irq_entry_sc); >> irqfd_deactivate(irqfd); >> + irq_bypass_unregister_consumer(irqfd->cons); >> + kfree(irqfd->cons); > > There may be an issue here. 'irqfd' is freed in irqfd_deactivate() --> ... > --.>irqfd_shutdown(), > and irqfd_deactivate() can be called in the other two places below: > - irqfd_wakeup() > - kvm_irqfd_release() > I think we also need to call irq_bypass_unregister_consumer() there, right? yes you're right. what about doing the unregistration in irqfd_shutdown then?
Thanks for spotting this. Eric > > Thanks, > Feng > > >> } >> } >> >> -- >> 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
