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

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

On Mon, Aug 13, 2012 at 08:06:17PM +0200, Jan Kiszka wrote:
> On 2012-08-13 20:03, Michael S. Tsirkin wrote:
> > On Mon, Aug 13, 2012 at 02:06:10PM +0200, Jan Kiszka wrote:
> >> On 2012-08-13 10:35, Nicholas A. Bellinger wrote:
> >>> From: Nicholas Bellinger <nab@linux-iscsi.org>
> >>>
> >>> This is required to get past the following assert with:
> >>>
> >>> commit 1523ed9e1d46b0b54540049d491475ccac7e6421
> >>> Author: Jan Kiszka <jan.kiszka@siemens.com>
> >>> Date:   Thu May 17 10:32:39 2012 -0300
> >>>
> >>>     virtio/vhost: Add support for KVM in-kernel MSI injection
> >>>
> >>> Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
> >>> Cc: Jan Kiszka <jan.kiszka@siemens.com>
> >>> Cc: Paolo Bonzini <pbonzini@redhat.com>
> >>> Cc: Anthony Liguori <aliguori@us.ibm.com>
> >>> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
> >>> ---
> >>>  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);
> >>>  
> >>>
> >>
> >> I think to remember pointing out that there is a bug somewhere in the
> >> reset code which deactivates a non-active vhost instance, no?
> >>
> >> Jan
> > 
> > Could not find it. Could you dig it up pls?
> 
> http://thread.gmane.org/gmane.linux.scsi.target.devel/2277/focus=2309
> 
> Jan

Ah yes. So let's not work around, need to get to the bottom of that.

> -- 
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