RE: [PATCH v2] doc: fix vhost multi-queue reconnection

["Ding, Xuan" <xuan.ding@intel.com>]

Hi Maxime,

> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> Sent: Tuesday, March 29, 2022 8:47 PM
> To: Ding, Xuan <xuan.ding@intel.com>; Xia, Chenbo <chenbo.xia@intel.com>
> Cc: dev@dpdk.org; Hu, Jiayu <jiayu.hu@intel.com>; stable@dpdk.org
> Subject: Re: [PATCH v2] doc: fix vhost multi-queue reconnection
> 
> 
> 
> On 2/24/22 07:28, xuan.ding@intel.com wrote:
> > From: Xuan Ding <xuan.ding@intel.com>
> >
> > Since QEMU 5.2.0 fixes the vhost multi-queue reconnection issue in
> > commit f66337bdbfda ("vhost-user: save features of multiqueues if
> > chardev is closed"), this patch removes the previous description from
> > known issue.
> >
> > Fixes: b37e95507e1b ("doc: add vhost multi-queue reconnection issue")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Xuan Ding <xuan.ding@intel.com>
> > ---
> > v2:
> > * Add fixes in commit title and log.
> > ---
> >   doc/guides/rel_notes/known_issues.rst | 21 ---------------------
> >   1 file changed, 21 deletions(-)
> >
> > diff --git a/doc/guides/rel_notes/known_issues.rst
> > b/doc/guides/rel_notes/known_issues.rst
> > index 187d9c942e..a8d1401a71 100644
> > --- a/doc/guides/rel_notes/known_issues.rst
> > +++ b/doc/guides/rel_notes/known_issues.rst
> > @@ -884,24 +884,3 @@ Unsuitable IOVA mode may be picked as the
> default
> >
> >   **Driver/Module**:
> >      ALL.
> > -
> > -Vhost multi-queue reconnection failed with QEMU version >= 4.2.0
> > -----------------------------------------------------------------
> > -
> > -**Description**
> > -   It's a QEMU regression bug (bad commit: c6beefd674ff). QEMU only
> saves
> > -   acked features for one vhost-net when vhost quits. When vhost
> reconnects
> > -   to virtio-net/virtio-pmd in multi-queue situations, the features been
> > -   set multiple times are not consistent.
> > -
> > -**Implication**
> > -   Vhost cannot reconnect back to virtio-net/virtio-pmd normally.
> > -
> > -**Resolution/Workaround**:
> > -   It is possible to filter the incorrect acked features at vhost-user side.
> > -
> > -**Affected Environment/Platform**:
> > -   ALL.
> > -
> > -**Driver/Module**:
> > -   Virtual Device Poll Mode Driver (PMD).
> 
> Instead of removing this information, I would rather update it to indicate the
> range of affected QEMU versions.
> 
> What do you think?

That's a good idea, so that users can know which versions are affected.
I will update it in next version.

Thanks,
Xuan

> 
> Thanks,
> Maxime