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

[Blue Swirl]

On 6/9/09, Gleb Natapov <address@hidden> wrote:
> 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 <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.
>  >
>
> So somebody (not me) should go and fix all others.

Here's a 5 min patch to add reset to e1000 and rtl8139. Not too difficult?

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

If we go to this, I'd also make savevm/loadvm mandatory.

0001-Register-reset-functions-for-e1000-and-rtl8139.patch
Description: Source code patch