Re: passthroughed msix device

[Zhenzhong Duan <zhenzhong.duan@oracle.com>]

On 2013-02-26 18:08, Jan Beulich wrote:
>>>> On 26.02.13 at 09:56, DuanZhenzhong <zhenzhong.duan@oracle.com> wrote:
>> pci_msix_writel: Can't update entry 0 since MSI-X is already enabled
>> (fee00000 -> fee02000)
>> pci_msix_writel: Can't update entry 0 since MSI-X is already enabled
>> (00004059 -> 00004071)
> If you look at the code issuing this message, the situation is
> pretty clear (and I think it as described already in the past,
> albeit I have no link at hand): qemu lacks proper emulation of
> the mask bit. pci_msix_write() looks at the physical one, yet
> when the guest sets the virtual mask bit, nothing is being
> done at all to make the hypervisor also mask the physical
> entry:
>
>      if (offset == PCI_MSIX_ENTRY_VECTOR_CTRL) {
>          if (msix->enabled && !(val & PCI_MSIX_ENTRY_CTRL_MASKBIT)) {
>              xen_pt_msix_update_one(s, entry_nr);
>          }
>      }
>
> There's probably quite a bit of code to be written to make this
> work.
Is there plan of fixing it?

thanks
zduan