Re: [PATCH] Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()

["gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>]

On Thu, Jan 26, 2017 at 06:10:19AM +0000, Dexuan Cui wrote:
> > From: Stephen Hemminger [mailto:stephen@networkplumber.org]
> > Sent: Wednesday, January 25, 2017 00:08
> > To: Dexuan Cui <decui@microsoft.com>
> > Cc: gregkh@linuxfoundation.org; driverdev-devel@linuxdriverproject.org; KY
> > Srinivasan <kys@microsoft.com>; Haiyang Zhang <haiyangz@microsoft.com>;
> > Stephen Hemminger <sthemmin@microsoft.com>; olaf@aepfle.de; Rolf
> > Neugebauer <rolf.neugebauer@docker.com>; jasowang@redhat.com; linux-
> > kernel@vger.kernel.org; apw@canonical.com
> > Subject: Re: [PATCH] Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
> > 
> > On Tue, 24 Jan 2017 06:54:46 +0000
> > Dexuan Cui <decui@microsoft.com> wrote:
> > 
> > > +static inline void
> > > +init_cached_read_index(struct vmbus_channel *channel)
> > > +{
> > > +	struct hv_ring_buffer_info *rbi = &channel->inbound;
> > > +
> > > +	rbi->cached_read_index = rbi->ring_buffer->read_index;
> > > +}
> > 
> > Looks good thanks. This should go in right away. Which versions are impacted?
> > Should it also go to stable?
> 
> Yes, it needs to go to stable.
> I have Cc-ed  <stable@vger.kernel.org> in the patch's changelog, so it should be
> included in the stable tree automatically.
> 
> As I checked against the kernels listed on the homapage of www.kernel.org, the
> below versions are impacted:
> v3.16.39
> v3.18.47
> v4.1.38
> v4.8.17
> v4.9.5
> v4.10-rc5
> 
> It's interesting v4.4.44 is not impacted, but actually it needs both the 2 patches:
> i.e. this patch, and the previous one:
> Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()")

That patch does not apply to the 4.4-stable tree, which is why it was
not included there.  If you feel it should be included, please provide a
backport and send it to the stable@vger.kernel.org mailing list.

thanks,

greg k-h