Re: [v3.16.y-ckt][v3.18.y][v3.19.y-ckt][v4.0.y][PATCH 1/1]Drivers: hv: vmbus: Add support for VMBus panic notifier handler

[Kamal Mostafa <kamal@canonical.com>]

On Fri, 2015-06-26 at 17:47 -0700, Greg KH wrote:
> On Tue, Jun 16, 2015 at 04:22:12PM -0400, Joseph Salisbury wrote:
> > From: Nick Meier <nmeier@microsoft.com>
> > 
> > BugLink: http://bugs.launchpad.net/bugs/1463584
> > 
> > Hyper-V allows a guest to notify the Hyper-V host that a panic
> > condition occured.  This notification can include up to five 64
> > bit values.  These 64 bit values are written into crash MSRs.
> > Once the data has been written into the crash MSRs, the host is
> > then notified by writing into a Crash Control MSR.  On the Hyper-V
> > host, the panic notification data is captured in the Windows Event
> > log as a 18590 event.
> > 
> > Crash MSRs are defined in appendix H of the Hypervisor Top Level
> > Functional Specification.  At the time of this patch, v4.0 is the
> > current functional spec.  The URL for the v4.0 document is:
> > 
> > http://download.microsoft.com/download/A/B/4/AB43A34E-BDD0-4FA6-BDEF-79EEF16E880B/Hypervisor Top Level Functional Specification v4.0.docx
> > 
> > Signed-off-by: Nick Meier <nmeier@microsoft.com>
> > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > (Backported from commit 96c1d0581d00f7abe033350edb021a9d947d8d81)
> > Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>
> > ---
> >  drivers/hv/hyperv_vmbus.h | 11 +++++++++++
> >  drivers/hv/vmbus_drv.c    | 35 +++++++++++++++++++++++++++++++++++
> >  2 files changed, 46 insertions(+)
> 
> This is a new feature, why should it be added to -stable releases?
> 
> Sorry, not going to take it, upgrade to 4.1 if you want this feature.
> 
> greg k-h

Greg is right: this isn't suitable for stable, so Luís and I will also
drop/revert these from the -ckt stable kernels (3.13, 3.16, and 3.19):

        Drivers: hv: vmbus: Add support for VMBus panic notifier handler
        Drivers: hv: vmbus: Correcting truncation error for constant HV_CRASH_CTL_CRASH_NOTIFY

Sasha, it looks like you've already dropped them from 3.18 but heads-up
just in case.

Thanks Greg!

 -Kamal