Re: [Qemu-devel] [RFC-v2 1/6] msix: Work-around for vhost-scsi with KVM in-kernel MSI injection

[Michael S. Tsirkin]

On Mon, Aug 13, 2012 at 08:35:12AM +0000, Nicholas A. Bellinger wrote:
> From: Nicholas Bellinger <address@hidden>
> 
> This is required to get past the following assert with:
> 
> commit 1523ed9e1d46b0b54540049d491475ccac7e6421
> Author: Jan Kiszka <address@hidden>
> Date:   Thu May 17 10:32:39 2012 -0300
> 
>     virtio/vhost: Add support for KVM in-kernel MSI injection
> 
> Cc: Stefan Hajnoczi <address@hidden>
> Cc: Jan Kiszka <address@hidden>
> Cc: Paolo Bonzini <address@hidden>
> Cc: Anthony Liguori <address@hidden>
> Signed-off-by: Nicholas Bellinger <address@hidden>

Could you please add a bit more explanation why
this happens with virtio scsi and why this is valid?

> ---
>  hw/msix.c |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/msix.c b/hw/msix.c
> index 800fc32..c1e6dc3 100644
> --- a/hw/msix.c
> +++ b/hw/msix.c
> @@ -544,6 +544,9 @@ void msix_unset_vector_notifiers(PCIDevice *dev)
>  {
>      int vector;
>  
> +    if (!dev->msix_vector_use_notifier && !dev->msix_vector_release_notifier)
> +        return;
> +
>      assert(dev->msix_vector_use_notifier &&
>             dev->msix_vector_release_notifier);
>  
> -- 
> 1.7.2.5