Date: Tue, 26 Sep 2017 14:00:32 +0200
From: Jan Glauber <jan.glauber@caviumnetworks.com>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: Vadim Lomovtsev <Vadim.Lomovtsev@caviumnetworks.com>,
        kvm@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jon Masters <jcm@redhat.com>,
        linux-arm-kernel@lists.infradead.org, david.daney@cavium.com,
        Robert Richter <robert.richter@cavium.com>,
        Alex Williamson <alex.williamson@redhat.com>
Subject: Re: [v4,0/3] Workaround for bus/slot reset on Cavium cn8xxx root
 ports
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On Wed, Sep 20, 2017 at 12:09:12PM -0600, Alex Williamson wrote:
> On Tue, 12 Sep 2017 02:40:49 -0700
> Vadim Lomovtsev <Vadim.Lomovtsev@caviumnetworks.com> wrote:
> 
> > Hi all,
> > 
> > Are there any updates on this ?
> > Comments/objections/acks/nacks ?
> > 
> > WBBR,
> > Vadim
> > 
> > On Fri, Sep 08, 2017 at 10:10:30AM +0200, Jan Glauber wrote:
> > > Using vfio-pci on a combination of cn8xxx and some PCI devices results in
> > > a kernel panic. This is triggered by issuing a bus or a slot reset
> > > on the PCI device.
> > > 
> > > With this series both checks indicate that the reset is not possible
> > > preventing the kernel panic.
> > > 
> > > David Daney (2):
> > >   PCI: Allow PCI_DEV_FLAGS_NO_BUS_RESET to be used on bus device
> > >   PCI: Avoid bus reset for Cavium cn8xxx root ports
> > > 
> > > Jan Glauber (1):
> > >   PCI: Avoid slot reset if bus reset is not possible
> > > 
> > >  drivers/pci/pci.c    | 8 ++++++++
> > >  drivers/pci/quirks.c | 8 ++++++++
> > >  2 files changed, 16 insertions(+)  
> 
> 
> Looks ok to me, for series:
> 
> Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
> 
> I am curious why we're happy targeting this quirk at a single device ID
> while at the same time trying to expand the ACS quirk to a notable
> fraction of the Cavium PCI device ID address space.  Thanks,
> 
> Alex

Bjorn, would you take these patches? 

We might need to extend the quirk to cover more cn8xxx variants,
this is not yet entirely clear on our side.

Therefore I'd like to ask if we could merge this patches now to solve the
long-standing issue for cn88xx.

thanks,
Jan