On Thu, 27 Jul 2017 13:37:24 -0500 Michael Roth <mdr...@linux.vnet.ibm.com> wrote:
> Quoting Greg Kurz (2017-07-27 12:09:55)
> > On Thu, 27 Jul 2017 14:41:31 +1000
> > Alexey Kardashevskiy <a...@ozlabs.ru> wrote:
> >
> > > On 26/07/17 18:40, Greg Kurz wrote:
> > > > Hotplugging PHBs is a machine-level operation, but PHBs reside on the
> > > > main system bus, so we register spapr machine as the handler for the
> > > > main system bus.
> > > >
> > > > Signed-off-by: Michael Roth <mdr...@linux.vnet.ibm.com>
> > > > Signed-off-by: Greg Kurz <gr...@kaod.org>
> > > > ---
> > > > - rebased against ppc-for-2.10
> > > > - converted to unplug_request
> > > > - handle drc_id at pre-plug
> > > > - reset hotplugged PHB at plug
> > > > - compatibility with older machine types
> > > > ---
> > > > hw/ppc/spapr.c | 114
> > > > +++++++++++++++++++++++++++++++++++++++++++
> > > > hw/ppc/spapr_drc.c | 1
> > > > hw/ppc/spapr_pci.c | 2 -
> > > > include/hw/pci-host/spapr.h | 2 +
> > > > include/hw/ppc/spapr.h | 1
> > > > 5 files changed, 118 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > > > index 90485054c2e7..589f76ef9fb8 100644
> > > > --- a/hw/ppc/spapr.c
> > > > +++ b/hw/ppc/spapr.c
> > > > @@ -2540,6 +2540,10 @@ static void ppc_spapr_init(MachineState *machine)
> > > > register_savevm_live(NULL, "spapr/htab", -1, 1,
> > > > &savevm_htab_handlers, spapr);
> > > >
> > > > + if (spapr->dr_phb_enabled) {
> > > > + qbus_set_hotplug_handler(sysbus_get_default(),
> > > > OBJECT(machine), NULL);
> > > > + }
> > > > +
> > > > qemu_register_boot_set(spapr_boot_set, spapr);
> > > >
> > > > if (kvm_enabled()) {
> > > > @@ -3238,6 +3242,103 @@ out:
> > > > error_propagate(errp, local_err);
> > > > }
> > > >
> > > > +static void spapr_phb_pre_plug(HotplugHandler *hotplug_dev,
> > > > DeviceState *dev,
> > > > + Error **errp)
> > > > +{
> > > > + sPAPRPHBState *sphb = SPAPR_PCI_HOST_BRIDGE(dev);
> > > > +
> > > > + if (sphb->drc_id == (uint32_t)-1) {
> > > > + sphb->drc_id = sphb->index;
> > > > + }
> > > > +
> > > > + if (sphb->drc_id >= SPAPR_DRC_MAX_PHB) {
> > > > + error_setg(errp, "PHB id %d out of range", sphb->drc_id);
> > > > + }
> > >
> > >
> > > sphb->index in considered 16bits in the existing code (even though it is
> > > defined as 32bit) and SPAPR_DRC_MAX_PHB is just 256. I'd suggest using the
> > > same limit for both, either 256 or 65536 is fine for me.
> > >
> > > It is actually a bit weird - it is possible to completely configure few
> > > PHBs in the command line so they will have index==-1 but PCI hotplug code
> > > -
> > > spapr_phb_get_pci_func_drc() and spapr_phb_realize() - does not check for
> > > this and just does (sphb->index << 16).
> >
> > You're right and this looks like a bug... I'll try to come up with a fix.
>
> Yup, that's a bug, and we can trigger it currently by adding 2
> additional PHBs that don't have an index specified. QOM catches
> and reports them as "attempt to add duplicate property", but it's
> just reported by spapr_dr_connector_new() and doesn't seem to be
> treated as fatal (and probably should be).
>
Yeah, spapr_dr_connector_new() doesn't care for errors at all and
happily returns a pointer to an unrealized DRC. This causes weird
behavior. For example, when using mandatory props instead of index:
-device spapr-pci-host-bridge,id=pci1,\
buid=0x800000020000001,\
liobn=0x80000100,\
liobn64=0x80000101,\
mem_win_addr=0x200100000000,\
mem64_win_addr=0x220000000000,\
io_win_addr=0x200000010000 \
-device spapr-pci-host-bridge,id=pci2,\
buid=0x800000020000002,\
liobn=0x80000200,\
liobn64=0x80000201,\
mem_win_addr=0x200180000000,\
mem64_win_addr=0x230000000000,\
io_win_addr=0x200000020000 \
-device virtio-net,id=hp1,bus=pci1.0 \
-device virtio-net,id=hp2,bus=pci2.0
QEMU complains and exits:
qemu-system-ppc64: -device virtio-net,id=hp2,bus=pci2.0: an attached device
is still awaiting release
> Might also see this more in practice now with the multi-phb support
> in libvirt, though I'd imagine those would tend to rely on phb->index
> being set.
>
I had confirmation from Shiva that libvirt passes the following to QEMU:
spapr-pci-host-bridge,index=X,id=pci.X<,numa_node=Z>
> Now that phb->drc_id is available though we can just use that instead.
> I agree it should be limited to 16-bit or smaller to avoid any
> possibility of overlap.
>
Well, David changed his mind and now suggests we rather make index mandatory
instead of adding drc_id (even if it breaks existing setups that don't rely
on index).
> >
> > > May be just ditch drc_id, enforce index not to be -1 and use it as drc_id?
> > >
> >
> > This was how Mike did it in the original patchset but David suggested
> > to introduce drc_id (to preserve existing setups I guess):
> >
> > http://patchwork.ozlabs.org/patch/466262/
>
> Althrough IIRC what David proposed was to handle it like the other
> properties which are filled in automatically when 'index' is specified,
> i.e. 'drc_id' would be set automatically by 'index' if index is
> specified, or we can set it explicitly if 'index' not specified, but
> if we try to set both 'index' and 'drc_id' we trigger the "Either "index"
> or other parameters must be specified for PAPR PHB, not both" error.
>
> And it looks like 'index' is limited to 30, so it fits within our
> 16-bit limit for drc_id.
>
> >
> > >
> > >
> > > > +}
> > > > +
> > > > +static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState
> > > > *dev,
> > > > + Error **errp)
> > > > +{
> > > > + sPAPRMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
> > > > + sPAPRPHBState *sphb = SPAPR_PCI_HOST_BRIDGE(dev);
> > > > + void *fdt = NULL;
> > > > + int fdt_start_offset;
> > > > + int fdt_size;
> > > > + Error *local_err = NULL;
> > > > + sPAPRDRConnector *drc;
> > > > + uint32_t phandle;
> > > > + int ret;
> > > > + bool hotplugged = spapr_drc_hotplugged(dev);
> > > > +
> > > > + if (!spapr->dr_phb_enabled) {
> > > > + return;
> > > > + }
> > > > +
> > > > + drc = spapr_drc_by_id(TYPE_SPAPR_DRC_PHB, sphb->drc_id);
> > > > + /* hotplug hooks should check it's enabled before getting this far
> > > > */
> > > > + g_assert(drc);
> > > > +
> > > > + if (hotplugged) {
> > > > + if (spapr->xics_phandle == UINT32_MAX) {
> > > > + error_setg(&local_err,
> > > > + "SLOF didn't update the XICS phandle. PHB
> > > > hotplug cancelled");
> > > > + goto out;
> > > > + }
> > > > + phandle = spapr->xics_phandle;
> > > > +
> > > > + spapr_phb_reset(dev);
> > >
> > >
> > > It could be DEVICE_GET_CLASS(dev)->reset(dev) without exporting
> > > spapr_phb_reset. Not sure how this fits into the current QEMU coding style
> > > though.
> > >
> > >
> > >
> > > > + } else {
> > > > + phandle = PHANDLE_XICP;
> > > > + }
> > > > +
> > > > + fdt = create_device_tree(&fdt_size);
> > > > + ret = spapr_populate_pci_dt(sphb, phandle, fdt, &fdt_start_offset);
> > > > + if (ret < 0) {
> > > > + error_setg(&local_err, "unable to create FDT for %sPHB",
> > > > + dev->hotplugged ? "hotplugged " : "");
> > > > + goto out;
> > > > + }
> > > > +
> > > > + if (hotplugged) {
> > > > + /* generally SLOF creates these, for hotplug it's up to QEMU */
> > > > + _FDT(fdt_setprop_string(fdt, fdt_start_offset, "name", "pci"));
> > > > + }
> > > > +
> > > > + spapr_drc_attach(drc, DEVICE(dev), fdt, fdt_start_offset,
> > > > &local_err);
> > > > +out:
> > > > + if (local_err) {
> > > > + error_propagate(errp, local_err);
> > > > + g_free(fdt);
> > > > + return;
> > > > + }
> > > > +
> > > > + if (hotplugged) {
> > > > + spapr_hotplug_req_add_by_index(drc);
> > > > + } else if (drc) {
> > > > + spapr_drc_reset(drc);
> > > > + }
> > > > +}
> > > > +
> > > > +void spapr_phb_release(DeviceState *dev)
> > > > +{
> > > > + object_unparent(OBJECT(dev));
> > > > +}
> > > > +
> > > > +static void spapr_phb_unplug_request(HotplugHandler *hotplug_dev,
> > > > + DeviceState *dev, Error **errp)
> > > > +{
> > > > + sPAPRPHBState *sphb = SPAPR_PCI_HOST_BRIDGE(dev);
> > > > + sPAPRDRConnector *drc;
> > > > +
> > > > + drc = spapr_drc_by_id(TYPE_SPAPR_DRC_PHB, sphb->drc_id);
> > > > + g_assert(drc);
> > > > +
> > > > + if (!spapr_drc_unplug_requested(drc)) {
> > > > + spapr_drc_detach(drc);
> > > > + spapr_hotplug_req_remove_by_index(drc);
> > > > + }
> > > > +}
> > > > +
> > > > static void spapr_machine_device_plug(HotplugHandler *hotplug_dev,
> > > > DeviceState *dev, Error **errp)
> > > > {
> > > > @@ -3284,6 +3385,8 @@ static void
> > > > spapr_machine_device_plug(HotplugHandler *hotplug_dev,
> > > > spapr_memory_plug(hotplug_dev, dev, node, errp);
> > > > } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) {
> > > > spapr_core_plug(hotplug_dev, dev, errp);
> > > > + } else if (object_dynamic_cast(OBJECT(dev),
> > > > TYPE_SPAPR_PCI_HOST_BRIDGE)) {
> > > > + spapr_phb_plug(hotplug_dev, dev, errp);
> > > > }
> > > > }
> > > >
> > > > @@ -3311,6 +3414,12 @@ static void
> > > > spapr_machine_device_unplug_request(HotplugHandler *hotplug_dev,
> > > > return;
> > > > }
> > > > spapr_core_unplug_request(hotplug_dev, dev, errp);
> > > > + } else if (object_dynamic_cast(OBJECT(dev),
> > > > TYPE_SPAPR_PCI_HOST_BRIDGE)) {
> > > > + if (sms->dr_phb_enabled) {
> > > > + spapr_phb_unplug_request(hotplug_dev, dev, errp);
> > > > + } else {
> > > > + error_setg(errp, "PHB hot unplug not supported on this
> > > > machine");
> > > > + }
> > > > }
> > > > }
> > > >
> > > > @@ -3321,6 +3430,8 @@ static void
> > > > spapr_machine_device_pre_plug(HotplugHandler *hotplug_dev,
> > > > spapr_memory_pre_plug(hotplug_dev, dev, errp);
> > > > } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) {
> > > > spapr_core_pre_plug(hotplug_dev, dev, errp);
> > > > + } else if (object_dynamic_cast(OBJECT(dev),
> > > > TYPE_SPAPR_PCI_HOST_BRIDGE)) {
> > > > + spapr_phb_pre_plug(hotplug_dev, dev, errp);
> > > > }
> > > > }
> > > >
> > > > @@ -3328,7 +3439,8 @@ static HotplugHandler
> > > > *spapr_get_hotplug_handler(MachineState *machine,
> > > > DeviceState *dev)
> > > > {
> > > > if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) ||
> > > > - object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) {
> > > > + object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE) ||
> > > > + object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_PCI_HOST_BRIDGE)) {
> > > > return HOTPLUG_HANDLER(machine);
> > > > }
> > > > return NULL;
> > > > diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c
> > > > index 2e1049ce61c7..845fcf70b932 100644
> > > > --- a/hw/ppc/spapr_drc.c
> > > > +++ b/hw/ppc/spapr_drc.c
> > > > @@ -704,6 +704,7 @@ static void spapr_drc_phb_class_init(ObjectClass
> > > > *k, void *data)
> > > > drck->typeshift = SPAPR_DR_CONNECTOR_TYPE_SHIFT_PHB;
> > > > drck->typename = "PHB";
> > > > drck->drc_name_prefix = "PHB ";
> > > > + drck->release = spapr_phb_release;
> > > > }
> > > >
> > > > static const TypeInfo spapr_dr_connector_info = {
> > > > diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> > > > index 157867af8178..c12f71ae3e2d 100644
> > > > --- a/hw/ppc/spapr_pci.c
> > > > +++ b/hw/ppc/spapr_pci.c
> > > > @@ -1833,7 +1833,7 @@ void spapr_phb_dma_reset(sPAPRPHBState *sphb)
> > > > sphb->dma_win_size >> SPAPR_TCE_PAGE_SHIFT);
> > > > }
> > > >
> > > > -static void spapr_phb_reset(DeviceState *qdev)
> > > > +void spapr_phb_reset(DeviceState *qdev)
> > > > {
> > > > sPAPRPHBState *sphb = SPAPR_PCI_HOST_BRIDGE(qdev);
> > > >
> > > > diff --git a/include/hw/pci-host/spapr.h b/include/hw/pci-host/spapr.h
> > > > index 7837fb0b1110..15799cee4280 100644
> > > > --- a/include/hw/pci-host/spapr.h
> > > > +++ b/include/hw/pci-host/spapr.h
> > > > @@ -120,6 +120,8 @@ int spapr_populate_pci_dt(sPAPRPHBState *phb,
> > > >
> > > > void spapr_pci_rtas_init(void);
> > > >
> > > > +void spapr_phb_reset(DeviceState *qdev);
> > > > +
> > > > sPAPRPHBState *spapr_pci_find_phb(sPAPRMachineState *spapr, uint64_t
> > > > buid);
> > > > PCIDevice *spapr_pci_find_dev(sPAPRMachineState *spapr, uint64_t buid,
> > > > uint32_t config_addr);
> > > > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> > > > index f09c54d5bb94..a2f6782bdbbf 100644
> > > > --- a/include/hw/ppc/spapr.h
> > > > +++ b/include/hw/ppc/spapr.h
> > > > @@ -673,6 +673,7 @@ void spapr_reallocate_hpt(sPAPRMachineState *spapr,
> > > > int shift,
> > > > /* CPU and LMB DRC release callbacks. */
> > > > void spapr_core_release(DeviceState *dev);
> > > > void spapr_lmb_release(DeviceState *dev);
> > > > +void spapr_phb_release(DeviceState *dev);
> > > >
> > > > void spapr_rtc_read(sPAPRRTCState *rtc, struct tm *tm, uint32_t *ns);
> > > > int spapr_rtc_import_offset(sPAPRRTCState *rtc, int64_t legacy_offset);
> > > >
> > > >
> > >
> > >
> >
>
pgpF4o8Yvr2ZT.pgp
Description: OpenPGP digital signature
