Re: [Qemu-devel] [PATCH 2/3] Add pci_bus_reset() function.

[Dor Laor]

Gleb Natapov wrote:
> On Mon, Jun 08, 2009 at 05:35:11PM +0300, Avi Kivity wrote:
>   
> > Gleb Natapov wrote:
> >     
> > > To reset internal irq handling data structures.
> > >
> > > Signed-off-by: Gleb Natapov <address@hidden>
> > > Signed-off-by: Yaniv Kamay <address@hidden>
> > > ---
> > >  hw/pci.c |   16 ++++++++++++++++
> > >  1 files changed, 16 insertions(+), 0 deletions(-)
> > >
> > > diff --git a/hw/pci.c b/hw/pci.c
> > > index 02b335f..89fefdf 100644
> > > --- a/hw/pci.c
> > > +++ b/hw/pci.c
> > > @@ -88,6 +88,21 @@ static int  pcibus_load(QEMUFile *f, void *opaque, int 
> > > version_id)
> > >      return 0;
> > >  }
> > >  +static void pci_bus_reset(void *opaque)
> > > +{
> > > +    PCIBus *bus = (PCIBus *)opaque;
> > > +    int i;
> > > +
> > > +    for (i = 0; i < bus->nirq; i++) {
> > > +        bus->irq_count[i] = 0;
> > > +    }
> > > +    for (i = 0; i < PCI_DEVICES_MAX; i++) {
> > > +        if (bus->devices[i])
> > > +            memset(bus->devices[i]->irq_state, 0,
> > > +                   sizeof(bus->devices[i]->irq_state));
> > > +    }
> > > +}
> > > +
> > >   
> > >       
> > Shouldn't each device's reset function bring its line low, thus zeroing  
> > the irq_state naturally?
> >
> > If not, we have a bug somewhere.  Note we have exactly the same issue  
> > with save/restore.
> >
> >     
> They should, but I haven't found one that does.
>   
virtio does and so do many others. Sad thing is that all should do it 
since the line is shared.
e1000 and rtl8139 do not register a reset handler.

Maybe we should make it a required callback for pci_qdev_register? or better
have every (pci?) device register several callback together.