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Date: Mon, 27 Apr 2015 14:32:38 +0200 (CEST)
From: Julia Lawall <julia.lawall@lip6.fr>
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To: "Michael S. Tsirkin" <mst@redhat.com>
cc: Julia Lawall <julia.lawall@lip6.fr>, zhanghy@sangfor.com,
        jasowang@redhat.com, pbonzini@redhat.com, x86@kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: KVM: x86: question about kvm_ioapic_destroy
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On Mon, 27 Apr 2015, Michael S. Tsirkin wrote:

> On Sun, Apr 26, 2015 at 07:19:58PM +0200, Julia Lawall wrote:
> > The function kvm_ioapic_destroy is defined as follows:
> >
> > void kvm_ioapic_destroy(struct kvm *kvm)
> > {
> >         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
> >
> >         cancel_delayed_work_sync(&ioapic->eoi_inject);
> >         if (ioapic) {
> >                 kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
> >                 kvm->arch.vioapic = NULL;
> >                 kfree(ioapic);
> >         }
> > }
> >
> > Is there any way that cancel_delayed_work_sync can work if ioapic is NULL?
> > Should the call be moved down under the NULL test?  Or is the NULL test
> > not needed?  The NULL test has been there longer than the call to
> > cancel_delayed_work_sync, which was introduced in 184564ef.
> >
> > thanks,
> > julia
>
> I think the NULL test is not needed.
> kvm_ioapic_destroy is only called if kvm_ioapic_init
> completed successfully, and that sets kvm->arch.vioapic.

Thanks.  I will send a patch.

julia