Re: [dpdk-stable] [PATCH v2] vhost: workaround MQ fails to startup

["Yang, Zhiyong" <zhiyong.yang@intel.com>]

Hi, all:

       The patch  which is used to fix the Qemu bug has been accepted in qemu community.
http://patchwork.ozlabs.org/patch/760118/

Thanks
Zhiyong

> -----Original Message-----
> From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com]
> Sent: Friday, April 28, 2017 12:29 PM
> To: Maxime Coquelin <maxime.coquelin@redhat.com>
> Cc: Yang, Zhiyong <zhiyong.yang@intel.com>; dev@dpdk.org; Loftus, Ciara
> <ciara.loftus@intel.com>; stable@dpdk.org
> Subject: Re: [PATCH v2] vhost: workaround MQ fails to startup
> 
> On Thu, Apr 27, 2017 at 12:00:52PM +0200, Maxime Coquelin wrote:
> >
> >
> > On 04/27/2017 11:41 AM, Zhiyong Yang wrote:
> > >   vhost since dpdk17.02 + qemu2.7 and above will cause failures of
> > >new connection when negotiating to set MQ. (one queue pair works
> > >well).
> > >    Because there exist some bugs in qemu code when introducing
> > >VHOST_USER_PROTOCOL_F_REPLY_ACK to qemu. when dealing with the
> vhost
> > >message VHOST_USER_SET_MEM_TABLE for the second time, qemu indeed
> > >doesn't send the messge (The message needs to be sent only once)but
> > >still will be waiting for dpdk's reply ack, then, qemu is always
> > >freezing. DPDK code indeed works in the right way.
> > >    The feature VHOST_USER_PROTOCOL_F_REPLY_ACK has to be disabled by
> > >default at the dpdk side in order to avoid the feature support of
> > >DPDK + qemu at the same time. if doing like that, MQ can works well.
> > >
> > >Cc: stable@dpdk.org
> > >
> > >Reported-by: Ciara Loftus <ciara.loftus@intel.com>
> > >Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
> > >Tested-by: Ciara Loftus <ciara.loftus@intel.com>
> > >---
> > >
> > >changes in V2
> > >1. modify "workaround" instead of "fix" in the title.
> > >2. add a simple comment suggested by yuanhan
> > >
> > >  lib/librte_vhost/vhost_user.h | 6 +++++-
> > >  1 file changed, 5 insertions(+), 1 deletion(-)
> > >
> >
> > Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> 
> Applied to dpdk-next-virtio.
> 
> Thanks.
> 
> 	--yliu