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

[Gleb Natapov <gleb@redhat.com>]

On Tue, Jun 09, 2009 at 12:42:16AM +0300, Dor Laor wrote:
> 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 <gleb@redhat.com>
>>>> Signed-off-by: Yaniv Kamay <ykamay@redhat.com>
>>>> ---
>>>>  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.
>
So somebody (not me) should go and fix all others.

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

--
			Gleb.