SLOF uses "pci" as name for PCI bridges nodes in the device tree instead
of "pci-bridges", so booting via bootindex from a device behind a PCI
bridge currently does not work since QEMU passes the wrong name in the
"qemu,boot-list" property. Fix it by changing the name of the PCI bridge
nodes to "pci" instead.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1459170Signed-off-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

DRC objects have attach & detach methods, but there's only one
implementation.  Although there are some differences in its behaviour for
different DRC types, the overall structure is the same, so while we might
want different method implementations for some parts, we're unlikely to
want them for the top-level functions.

So, replace them with direct function calls.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

With some combinations of migration and hotplug we can lost temporary state
indicating how many DRCs (guest side hotplug handles) are still connected
to a DIMM object in the process of removal.  When we hit that situation
spapr_recover_pending_dimm_state() is used to scan more extensively and
work out the right number.

It does this using drc->indicator state to determine what state of
disconnection the DRC is in.  However, this is not safe, because the
indicator state is guest settable - in fact it's more-or-less a purely
guest->host notification mechanism which should have no bearing on the
internals of hotplug state management.

So, replace the test for this with a test on drc->dev, which is a purely
qemu side managed variable, and updated the same BQL critical section as
the indicator state.

This does introduce an off-by-one change, because the indicator state was
updated before the call to spapr_lmb_release() on the current DRC, whereas
drc->dev is updated afterwards.  That's corrected by always decrementing
the nr_lmbs value instead of only doing so in the case where we didn't
have to recover information.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

The string returned by object_property_get_str() is dynamically allocated.

(Spotted by Coverity, CID 1375942)
Signed-off-by: NGreg Kurz <groug@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Currently the sPAPRMachineState contains a list of sPAPRConfigureConnector
structures which store intermediate state for the ibm,configure-connector
RTAS call.

This was an attempt to separate this state from the core of the DRC state.
However the configure connector process is intimately tied to the DRC
model, so there's really no point trying to have two levels of interface
here.

Moving the configure-connector state into its corresponding DRC allows
removal of a number of helpers for maintaining the anciliary list.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

 * Change names to something less ludicrously verbose
 * Now that we have QOM subclasses for the different DRC types, use a QOM
   typename instead of a PAPR type value parameter

The latter allows removal of the get_type_shift() helper.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

Currently we only have a single QOM type for all DRCs, but lots of
places where we switch behaviour based on the DRC's PAPR defined type.
This is a poor use of our existing type system.

So, instead create QOM subclasses for each PAPR defined DRC type.  We
also introduce intermediate subclasses for physical and logical DRCs,
a division which will be useful later on.

Instead of being stored in the DRC object itself, the PAPR type is now
stored in the class structure.  There are still many places where we
switch directly on the PAPR type value, but this at least provides the
basis to start to remove those.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

The current implementation of spapr_get_fw_dev_path() doesn't take into
consideration vhost-*-scsi devices. This makes said devices unbootable
on PPC as SLOF is unable to work out the path to scan boot disks.

This makes VMs bootable on spapr when using vhost-*-scsi by implementing
a disk path for VHostSCSICommon (which currently includes both
vhost-user-scsi and vhost-scsi).
Signed-off-by: NFelipe Franciosi <felipe@nutanix.com>
Signed-off-by: NMike Cui <cui@nutanix.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

These two methods only have one implementation, and the spec they're
implementing means any other implementation is unlikely, verging on
impossible.

So replace them with simple functions.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NLaurent Vivier <lvivier@redhat.com>
Tested-by: NDaniel Barboza <danielhb@linux.vnet.ibm.com>

even though spapr_fixup_cpu_numa_dt() has no effect on FDT
if numa is disabled, don't call it uselessly. It makes it
obvious at call sites that function is needed only when numa
is enabled.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Message-Id: <1496161442-96665-7-git-send-email-imammedo@redhat.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

Move vcpu's associated numa_node field out of generic CPUState
into inherited classes that actually care about cpu<->numa mapping,
i.e: ARMCPU, PowerPCCPU, X86CPU.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Message-Id: <1496161442-96665-6-git-send-email-imammedo@redhat.com>
[ehabkost: s/CPU is belonging to/CPU belongs to/ on comments]
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Message-Id: <1496161442-96665-2-git-send-email-imammedo@redhat.com>
[ehabkost: Fix indentation]
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

When a LMB hot unplug starts, the current DRC LMB status is stored at
spapr->pending_dimm_unplugs QTAILQ. This queue isn't migrated, thus
if a migration occurs in the middle of a LMB unplug the
spapr_lmb_release callback will lost track of the LMB unplug progress.

This patch implements a new recover function spapr_recover_pending_dimm_state
that is used inside spapr_lmb_release to recover this DRC LMB release
status that is lost during the migration.
Signed-off-by: NDaniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
[dwg: Minor stylistic changes, simplify error handling]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

The pointer drc->detach_cb is being used as a way of informing
the detach() function inside spapr_drc.c which cb to execute. This
information can also be retrieved simply by checking drc->type and
choosing the right callback based on it. In this context, detach_cb
is redundant information that must be managed.

After the previous spapr_lmb_release change, no detach_cb_opaques
are being used by any of the three callbacks functions. This is
yet another information that is now unused and, on top of that, can't
be migrated either.

This patch makes the following changes:

- removal of detach_cb_opaque. the 'opaque' argument was removed from
the callbacks and from the detach() function of sPAPRConnectorClass. The
attribute detach_cb_opaque of sPAPRConnector was removed.

- removal of detach_cb from the detach() call. The function pointer
detach_cb of sPAPRConnector was removed. detach() now uses a
switch(drc->type) to execute the apropriate callback. To achieve this,
spapr_core_release, spapr_lmb_release and spapr_phb_remove_pci_device_cb
callbacks were made public to be visible inside detach().
Signed-off-by: NDaniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

The LMB DRC release callback, spapr_lmb_release(), uses an opaque
parameter, a sPAPRDIMMState struct that stores the current LMBs that
are allocated to a DIMM (nr_lmbs). After each call to this callback,
the nr_lmbs is decremented by one and, when it reaches zero, the callback
proceeds with the qdev calls to hot unplug the LMB.

Using drc->detach_cb_opaque is problematic because it can't be migrated in
the future DRC migration work. This patch makes the following changes to
eliminate the usage of this opaque callback inside spapr_lmb_release:

- sPAPRDIMMState was moved from spapr.c and added to spapr.h. A new
attribute called 'addr' was added to it. This is used as an unique
identifier to associate a sPAPRDIMMState to a PCDIMM element.

- sPAPRMachineState now hosts a new QTAILQ called 'pending_dimm_unplugs'.
This queue of sPAPRDIMMState elements will store the DIMM state of DIMMs
that are currently going under an unplug process.

- spapr_lmb_release() will now retrieve the nr_lmbs value by getting the
correspondent sPAPRDIMMState. A helper function called spapr_dimm_get_address
was created to fetch the address of a PCDIMM device inside spapr_lmb_release.
When nr_lmbs reaches zero and the callback proceeds with the qdev hot unplug
calls, the sPAPRDIMMState struct is removed from spapr->pending_dimm_unplugs.

After these changes, the opaque argument for spapr_lmb_release is now
unused and is passed as NULL inside spapr_del_lmbs. This and the other
opaque arguments can now be safely removed from the code.

As an additional cleanup made by this patch, the spapr_del_lmbs function
was merged with spapr_memory_unplug_request. The former was being called
only by the latter and both were small enough to fit one single function.
Signed-off-by: NDaniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
[dwg: Minor stylistic cleanups]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

This allows to manage errors before the memory
has started to be hotplugged. We already have
the function for the CPU cores.
Signed-off-by: NLaurent Vivier <lvivier@redhat.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
[dwg: Fixed a couple of style nits]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

As of pseries-2.7 and later, we require the total number of guest vcpus to
be a multiple of the threads-per-core.  pseries-2.6 and earlier machine
types, however, are supposed to allow this for the sake of migration from
old qemu versions which allowed this.

Unfortunately, 8149e299 "pseries: Enforce homogeneous threads-per-core"
broke this by not considering the old machine type case.  This fixes it by
only applying the check when the machine type supports hotpluggable cpus.
By not-entirely-coincidence, that corresponds to the same time when we
started enforcing total threads being a multiple of threads-per-core.

Fixes: 8149e299Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NLaurent Vivier <lvivier@redhat.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
Tested-by: NGreg Kurz <groug@kaod.org>

If the user explicitely asked for kernel-irqchip support and "xics-kvm"
initialization fails, we shouldn't fallback to emulated "xics" as we
do now. It is also awkward to print an error message when we have an
errp pointer argument.

Let's use the errp argument to report the error and let the caller decide.
This simplifies the code as we don't need a local Error * here.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

If we go that far on the path of hot-removing a core and we find out that
the core-id is invalid, then we have a serious bug.

Let's make it explicit with an assert() instead of dereferencing a NULL
pointer.

This fixes Coverity issue CID 1375404.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Consolidate the code that frees HPT into a separate routine
spapr_free_hpt() as the same chunk of code is called from two places.
Signed-off-by: NBharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

The spapr_ics_create() function handles errors in a rather convoluted
way, with two local Error * variables. Moreover, failing to parent the
ICS object to the machine should be considered as a bug but it is
currently ignored.

This patch addresses both issues.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

This function only does hypercall and RTAS-call registration, and thus
never returns an error. This patch adapt the prototype to reflect that.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Reviewed-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

it's safe to remove thread node_id != core node_id error
branch as machine_set_cpu_numa_node() also does mismatch
check and is called even before any CPU is created.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Acked-by: NDavid Gibson <david@gibson.dropbear.id.au>
Message-Id: <1494415802-227633-10-git-send-email-imammedo@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

it will allow switching from cpu_index to core based numa
mapping in follow up patches.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Message-Id: <1494415802-227633-3-git-send-email-imammedo@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

Originally CPU threads were by default assigned in
round-robin fashion. However it was causing issues in
guest since CPU threads from the same socket/core could
be placed on different NUMA nodes.
Commit fb43b73b (pc: fix default VCPU to NUMA node mapping)
fixed it by grouping threads within a socket on the same node
introducing cpu_index_to_socket_id() callback and commit
20bb648d (spapr: Fix default NUMA node allocation for threads)
reused callback to fix similar issues for SPAPR machine
even though socket doesn't make much sense there.

As result QEMU ended up having 3 default distribution rules
used by 3 targets /virt-arm, spapr, pc/.

In effort of moving NUMA mapping for CPUs into possible_cpus,
generalize default mapping in numa.c by making boards decide
on default mapping and let them explicitly tell generic
numa code to which node a CPU thread belongs to by replacing
cpu_index_to_socket_id() with @cpu_index_to_instance_props()
which provides default node_id assigned by board to specified
cpu_index.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
Message-Id: <1494415802-227633-2-git-send-email-imammedo@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

When there are more nodes than available memory to put the minimum
allowed memory by node, all the memory is put on the last node.

This is because we put (ram_size / nb_numa_nodes) &
~((1 << mc->numa_mem_align_shift) - 1); on each node, and in this
case the value is 0. This is particularly true with pseries,
as the memory must be aligned to 256MB.

To avoid this problem, this patch uses an error diffusion algorithm [1]
to distribute equally the memory on nodes.

We introduce numa_auto_assign_ram() function in MachineClass
to keep compatibility between machine type versions.
The legacy function is used with pseries-2.9, pc-q35-2.9 and
pc-i440fx-2.9 (and previous), the new one with all others.

Example:

qemu-system-ppc64 -S -nographic  -nodefaults -monitor stdio -m 1G -smp 8 \
                  -numa node -numa node -numa node \
                  -numa node -numa node -numa node

Before:

(qemu) info numa
6 nodes
node 0 cpus: 0 6
node 0 size: 0 MB
node 1 cpus: 1 7
node 1 size: 0 MB
node 2 cpus: 2
node 2 size: 0 MB
node 3 cpus: 3
node 3 size: 0 MB
node 4 cpus: 4
node 4 size: 0 MB
node 5 cpus: 5
node 5 size: 1024 MB

After:
(qemu) info numa
6 nodes
node 0 cpus: 0 6
node 0 size: 0 MB
node 1 cpus: 1 7
node 1 size: 256 MB
node 2 cpus: 2
node 2 size: 0 MB
node 3 cpus: 3
node 3 size: 256 MB
node 4 cpus: 4
node 4 size: 256 MB
node 5 cpus: 5
node 5 size: 256 MB

[1] https://en.wikipedia.org/wiki/Error_diffusionSigned-off-by: NLaurent Vivier <lvivier@redhat.com>
Message-Id: <20170502162955.1610-2-lvivier@redhat.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
[ehabkost: s/ram_size/size/ at numa_default_auto_assign_ram()]
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

Logic in spapr_populate_pa_features() enables the bit advertising
Hardware Transactional Memory (HTM) in the guest's device tree only when
KVM advertises its availability with the KVM_CAP_PPC_HTM feature.

However, this assumes that the HTM bit is off in the base template used for
the device tree value.  That is true for POWER8, but not for POWER9.

It looks like that was accidentally changed in 9fb4541f "spapr: Enable ISA
3.0 MMU mode selection via CAS".

Fixes: 9fb4541fSigned-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NThomas Huth <thuth@redhat.com>

Now that we have added all the infrastructure we can enable a pseries TCG
guest to use radix.

In order to do this we have to add the appropriate bits to the
ibm,arch-vec-5-platform-support vector to represent that we support both
hash and radix mmu models.

A radix guest can now be booted in pseries tcg mode by specifying:
-cpu POWER9

Note that we assume hash, that is we allocate a hpt, until a guest tells
us otherwise via a H_REGISTER_PROCESS_TABLE call with radix specified - in
which case we free the hpt. If we were right and the guest is hash then
there's nothing for us to do.
Signed-off-by: NSuraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

xics_system_init() does not need 'nr_servers' anymore as it is only
used to define the 'interrupt-controller' node in the device tree. So
let's just compute the value when calling spapr_dt_xics().

This also gives us an opportunity to simplify the xics_system_init()
routine and introduce a specific spapr_ics_create() helper to create
the sPAPR ICS object.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Today, all the ICPs are created before the CPUs, stored in an array
under the sPAPR machine and linked to the CPU when the core threads
are realized. This modeling brings some complexity when a lookup in
the array is required and it can be simplified by allocating the ICPs
when the CPUs are.

This is the purpose of this proposal which introduces a new 'icp_type'
field under the machine and creates the ICP objects of the right type
(KVM or not) before the PowerPCCPU object are.

This change allows more cleanups : the removal of the icps array under
the sPAPR machine and the removal of the xics_get_cpu_index_by_dt_id()
helper.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

This is the second step to abstract the IRQ 'server' number of the
XICS layer. Now that the prereq cleanups have been done in the
previous patch, we can move down the 'cpu_dt_id' to 'cpu_index'
mapping in the sPAPR machine handler.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

This enables in-kernel handling of H_PUT_TCE_INDIRECT and
H_STUFF_TCE hypercalls. The host kernel support is there since v4.6,
in particular d3695aa4f452
("KVM: PPC: Add support for multiple-TCE hcalls").

H_PUT_TCE is already accelerated and does not need any special enablement.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

For a little while around 4.9, Linux kernels that saw the radix bit in
ibm,pa-features would attempt to set up the MMU as if they were a
hypervisor, even if they were a guest, which would cause them to
crash.

Work around this by detecting pre-ISA 3.0 guests by their lack of that
bit in option vector 1, and then removing the radix bit from
ibm,pa-features. Note: This now requires regeneration of that node
after CAS negotiation.
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Fix style nits]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Add the new node, /chosen/ibm,arch-vec-5-platform-support to the
device tree. This allows the guest to determine which modes are
supported by the hypervisor.

Update the option vector processing in h_client_architecture_support()
to handle the new MMU bits. This allows guests to request hash or
radix mode and QEMU to create the guest's HPT at this time if it is
necessary but hasn't yet been done.  QEMU will terminate the guest if
it requests an unavailable mode, as required by the architecture.

Extend the ibm,pa-features node with the new ISA 3.0 values
and set the radix bit if KVM supports radix mode. This probably won't
be used directly by guests to determine the availability of radix mode
(that is indicated by the new node added above) but the architecture
requires that it be set when the hardware supports it.

If QEMU is using KVM, and KVM is capable of running in radix mode,
guests can be run in real-mode without allocating a HPT (because KVM
will use a minimal RPT). So in this case, we avoid creating the HPT
at reset time and later (during CAS) create it if it is necessary.

ISA 3.0 guests will now begin to call h_register_process_table(),
which has been added previously.
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Strip some unneeded prefix from error messages]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

In the next patch, spapr_fixup_cpu_dt() will need to call
spapr_populate_pa_features() so move it's definition up without making
any other changes.
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

The H_REGISTER_PROCESS_TABLE H_CALL is used by a guest to indicate to the
hypervisor where in memory its process table is and how translation should
be performed using this process table.

Provide the implementation of this H_CALL for a guest.

We first check for invalid flags, then parse the flags to determine the
operation, and then check the other parameters for valid values based on
the operation (register new table/deregister table/maintain registration).
The process table is then stored in the appropriate location and registered
with the hypervisor (if running under KVM), and the LPCR_[UPRT/GTSE] bits
are updated as required.
Signed-off-by: NSuraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Correct missing prototype and uninitialized variable]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Use the new ioctl, KVM_PPC_GET_RMMU_INFO, to fetch radix MMU
information from KVM and present the page encodings in the device tree
under ibm,processor-radix-AP-encodings. This provides page size
information to the guest which is necessary for it to use radix mode.
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Compile fix for 32-bit targets, style nit fix]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Also use an 'sPAPRRTCState' attribute under the sPAPR machine to hold
the RTC object. Overall, these changes remove an unnecessary and
implicit dependency on SysBus.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

For reasons that may be useful in future, CPU core objects, as used on the
pseries machine type have their own nr-threads property, potentially
allowing cores with different numbers of threads in the same system.

If the user/management uses the values specified in query-hotpluggable-cpus
as they're expected to do, this will never matter in pratice.  But that's
not actually enforced - it's possible to manually specify a core with
a different number of threads from that in -smp.  That will confuse the
platform - most immediately, this can be used to create a CPU thread with
index above max_cpus which leads to an assertion failure in
spapr_cpu_core_realize().

For now, enforce that all cores must have the same, standard, number of
threads.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NBharata B Rao <bharata@linux.vnet.ibm.com>