On Thu, Mar 26, 2020 at 01:27:40PM +0100, Greg Kurz wrote: > On Thu, 26 Mar 2020 16:40:09 +1100 > David Gibson <da...@gibson.dropbear.id.au> wrote: > > > Currently, we can't properly handle unplug of NVLink2 devices, because we > > don't have code to tear down their special memory resources. There's not > > a lot of impetus to implement that. Since hardware NVLink2 devices can't > > be hot unplugged, the guest side drivers don't usually support unplug > > anyway. > > > > Therefore, simply prevent unplug of NVLink2 devices. > > > > This could maybe considered as a valid fix for 5.0 since this prevents > guest crashes IIUC. But since this requires the two preliminary cleanup > patches, I understand you may prefer to postpone that to 5.1.
Yeah, it's arguably a bug, but not a regression, so I'm inclined to
leave it to 5.1.
>
> > Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
> > ---
>
> Reviewed-by: Greg Kurz <gr...@kaod.org>
>
> > hw/ppc/spapr_pci.c | 5 +++++
> > 1 file changed, 5 insertions(+)
> >
> > diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> > index 55ca9dee1e..5c8262413a 100644
> > --- a/hw/ppc/spapr_pci.c
> > +++ b/hw/ppc/spapr_pci.c
> > @@ -1666,6 +1666,11 @@ static void spapr_pci_unplug_request(HotplugHandler
> > *plug_handler,
> > return;
> > }
> >
> > + if (spapr_phb_is_nvlink_dev(pdev, phb)) {
> > + error_setg(errp, "PCI: Cannot unplug NVLink2 devices");
> > + return;
> > + }
> > +
> > /* ensure any other present functions are pending unplug */
> > if (PCI_FUNC(pdev->devfn) == 0) {
> > for (i = 1; i < 8; i++) {
>
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
signature.asc
Description: PGP signature
