Re: [Qemu-devel] [PATCH for-2.0] pci: Fix clearing IRQs on reset

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Mar 31, 2014 at 02:31:44PM -0400, Cole Robinson wrote:
> irq_state is cleared before calling pci_device_deassert_intx, but the
> latter misbehaves if the former isn't accurate. In this case, any raised
> IRQs are not cleared, which hits an assertion in pcibus_reset:
> 
> qemu-system-x86_64: hw/pci/pci.c:250: pcibus_reset: Assertion
> `bus->irq_count[i] == 0' failed.
> 
> pci_device_deassert_intx should clear irq_state anyways, so add
> an assert.
> 
> This fixes migration with usb2 + usb-tablet.
> 
> Signed-off-by: Cole Robinson <crobinso@redhat.com>


Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

Peter, could you pick this up for RC3 if not too late?


> ---
>  hw/pci/pci.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 8f722dd..2a9f08e 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -189,9 +189,9 @@ static void pci_do_device_reset(PCIDevice *dev)
>  {
>      int r;
>  
> -    dev->irq_state = 0;
> -    pci_update_irq_status(dev);
>      pci_device_deassert_intx(dev);
> +    assert(dev->irq_state == 0);
> +
>      /* Clear all writable bits */
>      pci_word_test_and_clear_mask(dev->config + PCI_COMMAND,
>                                   pci_get_word(dev->wmask + PCI_COMMAND) |
> -- 
> 1.8.5.3