| Message ID | 20200331032709.112476-1-david@gibson.dropbear.id.au (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | spapr: Don't allow unplug of NVLink2 devices | expand |
On 31/03/2020 14:27, David Gibson 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. > > Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> > --- > hw/ppc/spapr_pci.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c > index 55ca9dee1e..61b84a392d 100644 > --- a/hw/ppc/spapr_pci.c > +++ b/hw/ppc/spapr_pci.c > @@ -1665,6 +1665,10 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler, > error_setg(errp, "PCI: Hot unplug of PCI bridges not supported"); > return; > } > + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", NULL)) { > + error_setg(errp, "PCI: Cannot unplug NVLink2 devices"); > + return; > + } > > /* ensure any other present functions are pending unplug */ > if (PCI_FUNC(pdev->devfn) == 0) { >
On 3/31/20 5:27 AM, David Gibson 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. Safe for 5.0, right? Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> > > Signed-off-by: David Gibson <david@gibson.dropbear.id.au> > --- > hw/ppc/spapr_pci.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c > index 55ca9dee1e..61b84a392d 100644 > --- a/hw/ppc/spapr_pci.c > +++ b/hw/ppc/spapr_pci.c > @@ -1665,6 +1665,10 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler, > error_setg(errp, "PCI: Hot unplug of PCI bridges not supported"); > return; > } > + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", NULL)) { > + error_setg(errp, "PCI: Cannot unplug NVLink2 devices"); > + return; > + } > > /* ensure any other present functions are pending unplug */ > if (PCI_FUNC(pdev->devfn) == 0) { >
On 31/03/2020 18:56, Philippe Mathieu-Daudé wrote: > On 3/31/20 5:27 AM, David Gibson 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. > > Safe for 5.0, right? I'd say so, yes. > > Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> > >> >> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> >> --- >> hw/ppc/spapr_pci.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c >> index 55ca9dee1e..61b84a392d 100644 >> --- a/hw/ppc/spapr_pci.c >> +++ b/hw/ppc/spapr_pci.c >> @@ -1665,6 +1665,10 @@ static void >> spapr_pci_unplug_request(HotplugHandler *plug_handler, >> error_setg(errp, "PCI: Hot unplug of PCI bridges not >> supported"); >> return; >> } >> + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", >> NULL)) { >> + error_setg(errp, "PCI: Cannot unplug NVLink2 devices"); >> + return; >> + } >> /* ensure any other present functions are pending unplug */ >> if (PCI_FUNC(pdev->devfn) == 0) {
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c index 55ca9dee1e..61b84a392d 100644 --- a/hw/ppc/spapr_pci.c +++ b/hw/ppc/spapr_pci.c @@ -1665,6 +1665,10 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler, error_setg(errp, "PCI: Hot unplug of PCI bridges not supported"); return; } + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", NULL)) { + error_setg(errp, "PCI: Cannot unplug NVLink2 devices"); + return; + } /* ensure any other present functions are pending unplug */ if (PCI_FUNC(pdev->devfn) == 0) {
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. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> --- hw/ppc/spapr_pci.c | 4 ++++ 1 file changed, 4 insertions(+)