Re: [PATCH v2 0/3] KVM: x86: use pic/ioapic destructor when proper

[Peter Xu <peterx@redhat.com>]

On Wed, Mar 15, 2017 at 12:15:24PM +0100, David Hildenbrand wrote:
> Am 15.03.2017 um 09:59 schrieb Peter Xu:
> > On Wed, Mar 15, 2017 at 09:47:14AM +0100, David Hildenbrand wrote:
> >> Am 15.03.2017 um 09:01 schrieb Peter Xu:
> >>> v2:
> >>> - add one more patch (patch 2 in v2) to check pic/ioapic's
> >>>   existance before destroying them
> >>
> >> Patch 2+3 without 1 should work, too, right?
> > 
> > We may need that? When destroy VM, it's:
> > 
> >   kvm_destroy_vm()
> >     foreach (bus) do kvm_io_bus_destroy()
> >       kfree(bus)                          <--- [1]
> >     kvm_arch_destroy_vm()
> >       kvm_pic_destroy()
> >         kvm_io_bus_unregister_dev()       <--- [2]
> > 
> 
> Wouldn't the natural way be
> 
> 1. kvm_arch_destroy_vm()
> 2. foreach (bus) do kvm_io_bus_destroy()
> 	kfree(bus)
> 
> Then we wouldn't have to deal with suddenly removed buses. But maybe
> that order is of importance here ...

I'll leave this question for Paolo/Radim, or anyone knows this better
than me. :-)

-- peterx