DRC objects attach themselves to an owner as a child
property. unref afterward to allow them to be finalized
when their owner is finalized.
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When hot-unplugging a PHB, all its PCI DRC connectors get unrealized. This
patch adds an unrealize method to the physical DRC class, in order to undo
registrations performed in realize_physical().
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Passing a stack allocated buffer of arbitrary length to snprintf()
without checking the return value can cause the resultant strings
to be silently truncated.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch is a follow up on the discussions made in patch
"hw/ppc: disable hotplug before CAS is completed" that can be
found at [1].
At this moment, we do not support CPU/memory hotplug in early
boot stages, before CAS. When a hotplug occurs, the event is logged
in an internal RTAS event log queue and an IRQ pulse is fired. In
regular conditions, the guest handles the interrupt by executing
check_exception, fetching the generated hotplug event and enabling
the device for use.
In early boot, this IRQ isn't caught (SLOF does not handle hotplug
events), leaving the event in the rtas event log queue. If the guest
executes check_exception due to another hotplug event, the re-assertion
of the IRQ ends up de-queuing the first hotplug event as well. In short,
a device hotplugged before CAS is considered coldplugged by SLOF.
This leads to device misbehavior and, in some cases, guest kernel
Ooops when trying to unplug the device.
A proper fix would be to turn every device hotplugged before CAS
as a colplugged device. This is not trivial to do with the current
code base though - the FDT is written in the guest memory at
ppc_spapr_reset and can't be retrieved without adding extra state
(fdt_size for example) that will need to managed and migrated. Adding
the hotplugged DT in the middle of CAS negotiation via the updated DT
tree works with CPU devs, but panics the guest kernel at boot. Additional
analysis would be necessary for LMBs and PCI devices. There are
questions to be made in QEMU/SLOF/kernel level about how we can make
this change in a sustainable way.
With Linux guests, a fix would be the kernel executing check_exception
at boot time, de-queueing the events that happened in early boot and
processing them. However, even if/when the newer kernels start
fetching these events at boot time, we need to take care of older
kernels that won't be doing that.
This patch works around the situation by issuing a CAS reset if a hotplugged
device is detected during CAS:
- the DRC conditions that warrant a CAS reset is the same as those that
triggers a DRC migration - the DRC must have a device attached and
the DRC state is not equal to its ready_state. With that in mind, this
patch makes use of 'spapr_drc_needed' to determine if a CAS reset
is needed.
- In the middle of CAS negotiations, the function
'spapr_hotplugged_dev_before_cas' goes through all the DRCs to see
if there are any DRC that requires a reset, using spapr_drc_needed. If
that happens, returns '1' in 'spapr_h_cas_compose_response' which will set
spapr->cas_reboot to true, causing the machine to reboot.
No changes are made for coldplug devices.
[1] http://lists.nongnu.org/archive/html/qemu-devel/2017-08/msg02855.html
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch makes a small fix in 'spapr_drc_needed' to change how we detect
if a DRC has a device attached. Previously it used dr_entity_sense for this,
which works for physical DRCs.
However, for logical DRCs, it didn't cover the case where a logical DRC has
a drc->dev but the state is LOGICAL_UNUSABLE (e.g. a hotplugged CPU before
CAS). In this case, the dr_entity_sense of this DRC returns UNUSABLE and the
code was considering that there were no dev attached, making spapr_drc_needed
return 'false' when in fact we would like to migrate the DRC.
Changing it to check for drc->dev instead works for all DRC types.
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
In case of in-kernel memory hot unplug, when the guest is not able
to remove all the LMBs that are requested for removal, it will add back
any LMBs that have been successfully removed. The DR Connectors of
these LMBs wouldn't have been unconfigured and hence the addition of
these LMBs will result in configure-connector call being issued on
LMB DR connectors that are already in configured state. Such
configure-connector calls will fail resulting in a DIMM which is
partially unplugged.
This however worked till recently before we overhauled the DRC
implementation in QEMU. Commit 9d4c0f4f0a71e: "spapr: Consolidate
DRC state variables" is the first commit where this problem shows up
as per git bisect.
Ideally guest shouldn't be issuing configure-connector call on an
already configured DR connector. However for now, work around this in
QEMU by allowing configure-connector to be called multiple times for
all types of DR connectors.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
[dwg: Corrected buglet that would have initialized fdt pointers ready
for reading on a device not present at reset]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
object_property_add_child() can only fail in two cases:
- the child already has a parent, which shouldn't happen since the DRC was
allocated a few lines above
- the parent already has a child with the same name, which would mean the
caller tries to create a DRC that already exists
In both case, this is a QEMU bug and we should abort.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
If object_property_add_alias() returns an error in realize(), we should
propagate it to the caller and certainly not unref the DRC.
Same thing goes for unrealize(). Since object_property_del() is the last
call, we can even get rid of the intermediate Error *.
And finally, unrealize() should undo all registrations performed by
realize().
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Make visit_type_null() take an @obj argument like its buddies. This
helps keep the next commit simple.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
According to PAPR, the DR-indicator should only be valid for physical DRCs,
not logical DRCs. At the moment we implement it for all DRCs, so restrict
it to physical ones only.
We move the state to the physical DRC subclass, which means adding some
QOM boilerplate to handle the newly distinct type.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Most of the time, the state of a DRC object is contained in the single
'state' variable. However, during the transition from UNISOLATE to
CONFIGURED state requires multiple calls to the ibm,configure-connector
RTAS call to retrieve the device tree for the attached device. We need
some extra state to keep track of where we're up to in delivering the
device tree information to the guest.
Currently that extra state is in a sPAPRConfigureConnectorState
substructure which is only allocated when we're in the middle of the
configure connector process. That sounds like a good idea, but the extra
state is only two integers - on many platforms that will take up the same
room as the (maybe NULL) ccs pointer even before malloc() overhead. Plus
it's another object whose lifetime we need to manage. In short, it's not
worth it.
So, fold the sPAPRConfigureConnectorState substructure directly into the
DRC object.
Previously the structure was allocated lazily when the configure-connector
call discovers it's not there. Now, we need to initialize the subfields
pre-emptively, as soon as we enter UNISOLATE state.
Although it's not strictly necessary (the field values should only ever
be consulted when in UNISOLATE state), we try to keep them at -1 when in
other states, as a debugging aid.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Each DRC has three fields describing its state: isolation_state,
allocation_state and configured. At first this seems like a reasonable
representation, since its based directly on the PAPR defined
isolation-state and allocation-state indicators. However:
* Only a few combinations of the two fields' values are permitted
* allocation_state isn't used at all for physical DRCs
* The indicators are write only so they don't really have a well
defined current value independent of each other
This replaces these variables with a single state variable, whose names
and numbers are based on the diagram in LoPAPR section 13.4. Along with
this we add code to check the current state on various operations and make
sure the requested transition is permitted.
Strictly speaking, this makes guest visible changes to behaviour (since we
probably allowed some transitions we shouldn't have before). However, a
hypothetical guest broken by that wasn't PAPR compliant, and probably
wouldn't have worked under PowerVM.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
'awaiting_release' indicates that the host has requested an unplug of the
device attached to the DRC, but the guest has not (yet) put the device
into a state where it is safe to complete removal.
1. Rename it to 'unplug_requested' which to me at least is clearer
2. Remove the ->release_pending() method used to check this from outside
spapr_drc.c. The method only plausibly has one implementation, so use
a plain function (spapr_drc_unplug_requested()) instead.
3. Remove it from the migration stream. Attempting to migrate mid-unplug
is broken not just for spapr - in general management has no good way to
determine if the device should be present on the destination or not. So,
until that's fixed, there's no point adding extra things to the stream.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
This function has two unused parameters - remove them.
It also sets awaiting_release on all paths, except one. On that path
setting it is harmless, since it will be immediately cleared by
spapr_drc_release(). So factor it out of the if statements.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
We currently ignore errors from the object_property_del() in
spapr_drc_release(). But the only way that could fail is if the property
doesn't exist, in which case it's a bug that we're in spapr_drc_release()
at all. So change from ignoring to abort()ing on errors.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The awaiting_allocation flag in the DRC was introduced by aab9913
"spapr_drc: Prevent detach racing against attach for CPU DR", allegedly to
prevent a guest crash on racing attach and detach. Except.. information
from the BZ actually suggests a qemu crash, not a guest crash. And there
shouldn't be a problem here anyway: if the guest has already moved the DRC
away from UNUSABLE state, the detach would already be deferred, and if it
hadn't it should be safe to detach it (the guest should fail gracefully
when it attempts to change the allocation state).
I think this was probably just a bandaid for some other problem in the
state management. So, remove awaiting_allocation and associated code.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
When migrating a guest which has already had devices hotplugged,
libvirt typically starts the destination qemu with -incoming defer,
adds those hotplugged devices with qmp, then initiates the incoming
migration.
This causes problems for the management of spapr DRC state. Because
the device is treated as hotplugged, it goes into a DRC state for a
device immediately after it's plugged, but before the guest has
acknowledged its presence. However, chances are the guest on the
source machine *has* acknowledged the device's presence and configured
it.
If the source has fully configured the device, then DRC state won't be
sent in the migration stream: for maximum migration compatibility with
earlier versions we don't migrate DRCs in coldplug-equivalent state.
That means that the DRC effectively changes state over the migrate,
causing problems later on.
In addition, logging hotplug events for these devices isn't what we
want because a) those events should already have been issued on the
source host and b) the event queue should get wiped out by the
incoming state anyway.
In short, what we really want is to treat devices added before an
incoming migration as if they were coldplugged.
To do this, we first add a spapr_drc_hotplugged() helper which
determines if the device is hotplugged in the sense relevant for DRC
state management. We only send hotplug events when this is true.
Second, when we add a device which isn't hotplugged in this sense, we
force a reset of the DRC state - this ensures the DRC is in a
coldplug-equivalent state (there isn't usually a system reset between
these device adds and the incoming migration).
This is based on an earlier patch by Laurent Vivier, cleaned up and
extended.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
All the DRC subtypes explicitly list instance_size in TypeInfo (all as
sizeof(sPAPRDRConnector). This isn't necessary, since if it's not listed
it will be derived from the parent type.
Worse, this is dangerous, because if a subtype is changed in future to
have a larger structure, then subtypes of that subtype also need to have
instance_size changed, or it will lead to hard to track memory corruption
bugs.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
spapr_drc_attach() has a 'coldplug' parameter which sets the DRC into
configured state initially, instead of the usual ISOLATED/UNUSABLE state.
It turns out this is unnecessary: although coldplugged devices do need to
be in CONFIGURED state once the guest starts, that will already be
accomplished by the reset code which will move DRCs for already plugged
devices into a coldplug equivalent state.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
At the moment, spapr_drc_release() has an ugly switch on the DRC type to
call the right, device-specific release function. This cleans it up by
doing that via a proper QOM method.
It's still arguably an abstraction violation for the DRC code to call into
the specific device code, but one mess at a time.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
DRC objects have a regular device reset method. However, it only gets
called in the usual way for PCI DRCs. Because of where CPU and LMB DRCs
are in the QOM tree, their device reset method isn't automatically called.
So, the machine manually registers reset handlers to call device_reset().
This patch removes the device reset method, and instead always explicitly
registers the reset handler from realize(). This means the callers don't
have to worry about the two cases, and we always get proper resets.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
The DR-indicator is essentially a "virtual LED" attached to a hotpluggable
device, which the guest can set to various states for the attention of
the operator or management layers.
It's mostly guest managed, except that we once-off set it to
ACTIVE/INACTIVE in the attach/detach path. While that makes certain sense,
there's no indication in PAPR that the hypervisor should do this, and the
drmgr code on the guest side doesn't appear to need it (it will already set
the indicator to ACTIVE on hotplug, and INACTIVE on remove).
So, leave the DR-indicator entirely to the guest; the only thing we need
to do is ensure it's in a sane state on reset.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
There are substantial differences in the various paths through
set_isolation_state(), both for setting to ISOLATED versus UNISOLATED
state and for logical versus physical DRCs.
So, split the set_isolation_state() method into isolate() and unisolate()
methods, and give it different implementations for the two DRC types.
Factor some minimal common checks, including for valid indicator values
(which we weren't previously checking) into rtas_set_isolation_state().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The allocation-state indicator should only actually be implemented for
"logical" DRCs, not physical ones. Factor a check for this, and also for
valid indicator state values into rtas_set_allocation_state(). Because
they don't exist for physical DRCs, there's no reason that we'd ever want
more than one method implementation, so it can just be a plain function.
In addition, the setting to USABLE and setting to UNUSABLE paths in
set_allocation_state() don't actually have much in common. So, split the
method separate functions for each parameter value (drc_set_usable()
and drc_set_unusable()).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The reset handler for DRCs attempts several state transitions which are
subject to various checks and restrictions. But at reset time we know
there is no guest, so we can ignore most of the usual sequencing rules and
just set the DRC back to a known state. In fact, it's safer to do so.
The existing code also has several redundant checks for
drc->awaiting_release inside a block which has already tested that. This
patch removes those and sets the DRC to a fixed initial state based only
on whether a device is currently plugged or not.
With DRCs correctly reset to a state based on device presence, we don't
need to force state transitions as cold plugged devices are processed.
This allows us to remove all the callers of the set_*_state() methods from
outside spapr_drc.c.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
spapr_drc_detach() is called when qemu generic code requests a device be
unplugged. It makes a number of tests, which could well delay further
action until later, before actually detach the device from the DRC.
This splits out the part which actually removes the device from the DRC
into spapr_drc_release(). This will be useful for further cleanups.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The 'signalled' field in the DRC appears to be entirely a torturous
workaround for the fact that PCI devices were started in UNISOLATED state
for unclear reasons.
1) 'signalled' is already meaningless for logical (so far, all non PCI)
DRCs. It's always set to true (at least at any point it might be tested),
and can't be assigned any real meaning due to the way signalling works for
logical DRCs.
2) For PCI DRCs, the only time signalled would be false is when non-zero
functions of a multifunction device are hotplugged, followed by function
zero (the other way around is explicitly not permitted). In that case the
secondary function DRCs are attached, but the notification isn't sent to
the guest until function 0 is plugged.
3) signalled being false is used to allow a DRC detach to switch mode
back to ISOLATED state, which allows a secondary function to be hotplugged
then unplugged with function 0 never inserted. Without this a secondary
function starting in UNISOLATED state couldn't be detached again without
function 0 being inserted, all the functions configured by the guest, then
sent back to ISOLATED state.
4) But now that PCI DRCs start in ISOLATED state, there's nothing to be
done. If the guest doesn't get the notification, it won't switch the
device to UNISOLATED state, so nothing prevents it from being unplugged.
If the guest does move it to UNISOLATED state without the signal (due to
a manual drmgr call, for instance) then it really isn't safe to unplug it.
So, this patch removes the signalled variable and all code related to it.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
PCI DRCs, and only PCI DRCs, are immediately moved to UNISOLATED isolation
state once the device is attached. This has been there from the initial
implementation, and it's not clear why.
The state diagram in PAPR 13.4 suggests PCI devices should start in
ISOLATED state until the guest moves them into UNISOLATED, and the code in
the guest-side drmgr tool seems to work that way too.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
This reverts commit fe6824d126.
Conflicts hw/ppc/spapr_drc.c, because get_index() has been renamed
spapr_get_index().
This didn't fix the problem. Once the hotplug has been started
some memory is allocated and some structures are allocated.
We don't free it when we ignore the unplug, and we can't because
they can be in use by the kernel.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
DRC objects have a get_name method which returns the DRC name generated
when the DRC is created. Replace that with a fixed spapr_drc_name()
function which generates the name on the fly from other information. This
means:
* We get rid of a method with only one implementation, and only local
callers
* We don't have to carry the name string around for the lifetime of the
DRC
* We use information added to the class structure to generate the name
in standard format, so we don't need an explicit switch on drc type
any more
We also eliminate the 'name' property; it's basically useless since the
only information in it can easily be deduced from other things.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
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: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
There are 3 types of "indicator" associated with hotplug in the PAPR spec
the "allocation state", "isolation state" and "DR-indicator". The first
two are intimately tied to the various state transitions associated with
hotplug. The DR-indicator, however, is different and simpler.
It's basically just a guest controlled variable which can be used by the
guest to flag state or problems associated with a device. The idea is that
the hypervisor can use it to present information back on management
consoles (on some machines with PowerVM it may even control physical LEDs
on the machine case associated with the relevant device).
For that reason, there's only ever likely to be a single update
implementation so the set_indicator_state method isn't useful. Replace it
with a direct function call.
While we're there, make some small associated cleanups:
* PAPR doesn't use the term "indicator state", just "DR-indicator" and
the allocation state and isolation state are also considered "indicators".
Rename things to be less confusing
* Fold set_indicator_state() and rtas_set_indicator_state() into a single
rtas_set_dr_indicator() function.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
In theory the RTAS set-indicator call can be used for a number of
"indicators" defined by PAPR. In practice the only ones we're ever likely
to implement are those used for Dynamic Reconfiguration (i.e. hotplug).
Because of this, the current implementation determines the associated DRC
object, before dispatching based on the type of indicator.
However, this means we also need a check that we're dealing with a DR
related indicator at all, which duplicates some of the logic from the
switch further down.
Even though it means a bit of code duplication, things work out cleaner if
we delegate the DRC lookup to the individual indicator type functions -
and it also allows some further cleanups.
While we're there, remove references to "sensor", a copy/paste artefact
from the related, but distinct "get-sensor" call.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
DRC classes have an entity_sense method to determine (in a specific PAPR
sense) the presence or absence of a device plugged into a DRC. However,
we only have one implementation of the method, which explicitly tests for
different DRC types. This changes it to instead have different method
implementations for the two cases: "logical" and "physical" DRCs.
While we're at it, the entity sense method always returns RTAS_OUT_SUCCESS,
and the interesting value is returned via pass-by-reference. Simplify this
to directly return the value we care about
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
* 'connector_type' is easily derived from the 'index' property, so there's
no point to it (it's also implicit in the QOM type of the DRC)
* 'isolation-state', 'indicator-state' and 'allocation-state' are
part of the transaction between qemu and guest during PAPR hotplug
operations, and outside tools really have no business looking at it
(especially not changing, and these were RW properties)
* 'entity-sense' is basically just a weird PAPR encoding of whether there
is a device connected to this DRC
Strictly speaking removing these properties is breaking the qemu interface.
However, I'm pretty sure no management tools have ever used these. For
debugging there are better alternatives. Therefore, I think removing these
broken interfaces is the better option.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
This function was used in generating the device tree. However, now that
we have different QOM types for different DRC types we can easily store
the information we need in the class structure and avoid this specialized
lookup function.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
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: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael 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: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael 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: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
As explained in commit 5c0139a8c2 ("spapr: fix default DRC state for
coldplugged LMBs"), guests expect cold-plugged LMBs to be pre-allocated
and unisolated. The same goes for cold-plugged CPUs.
While here, let's convert g_assert(false) to the better self documenting
g_assert_not_reached().
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David 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: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
DRConnectorClass has a set_configured method, however:
* There is only one implementation, and only ever likely to be one
* There's exactly one caller, and that's (now) local
* The implementation is very straightforward
So abolish the method entirely, and just open-code what we need.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
The DRConnectorClass includes a get_fdt method. However
* There's only one implementation, and there's only likely to ever be one
* Both callers are local to spapr_drc
* Each caller only uses one half of the actual implementation
So abolish get_fdt() entirely, and just open-code what we need.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Currently implementations of the RTAS calls related to DRCs are in
spapr_rtas.c. They belong better in spapr_drc.c - that way they're closer
to related code, and we'll be able to make some more things local.
spapr_rtas.c was intended to contain the RTAS infrastructure and core calls
that don't belong anywhere else, not every RTAS implementation.
Code motion only.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
In pseries, a firmware abstraction called Dynamic Reconfiguration
Connector (DRC) is used to assign a particular dynamic resource
to the guest and provide an interface to manage configuration/removal
of the resource associated with it. In other words, DRC is the
'plugged state' of a device.
Before this patch, DRC wasn't being migrated. This causes
post-migration problems due to DRC state mismatch between source and
target. The DRC state of a device X in the source might
change, while in the target the DRC state of X is still fresh. When
migrating the guest, X will not have the same hotplugged state as it
did in the source. This means that we can't hot unplug X in the
target after migration is completed because its DRC state is not consistent.
https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1677552 is one
bug that is caused by this DRC state mismatch between source and
target.
To migrate the DRC state, we defined the VMStateDescription struct for
spapr_drc to enable the transmission of spapr_drc state in migration.
Not all the elements in the DRC state are migrated - only those
that can be modified by guest actions or device add/remove
operations:
- 'isolation_state', 'allocation_state' and 'indicator_state'
are involved in the DR state transition diagram from
PAPR+ 2.7, 13.4;
- 'configured', 'signalled', 'awaiting_release' and 'awaiting_allocation'
are needed in attaching and detaching devices;
- 'indicator_state' provides users with hardware state information.
These are the DRC elements that are migrated.
In this patch the DRC state is migrated for PCI, LMB and CPU
connector types. At this moment there is no support to migrate
DRC for the PHB (PCI Host Bridge) type.
In the 'realize' function the DRC is registered using vmstate_register,
similar to what hw/ppc/spapr_iommu.c does in 'spapr_tce_table_realize'.
This approach works because DRCs are bus-less and do not sit
on a BusClass that implements bc->get_dev_path, so as a fallback the
VMSD gets identified via "spapr_drc"/get_index(drc).
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David 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: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
cannot_instantiate_with_device_add_yet was introduced by commit
efec3dd631 to replace no_user. It was
supposed to be a temporary measure.
When it was introduced, we had 54
cannot_instantiate_with_device_add_yet=true lines in the code.
Today (3 years later) this number has not shrunk: we now have
57 cannot_instantiate_with_device_add_yet=true lines. I think it
is safe to say it is not a temporary measure, and we won't see
the flag go away soon.
Instead of a long field name that misleads people to believe it
is temporary, replace it a shorter and less misleading field:
user_creatable.
Except for code comments, changes were generated using the
following Coccinelle patch:
@@
expression DC;
@@
(
-DC->cannot_instantiate_with_device_add_yet = false;
+DC->user_creatable = true;
|
-DC->cannot_instantiate_with_device_add_yet = true;
+DC->user_creatable = false;
)
@@
typedef ObjectClass;
expression dc;
identifier class, data;
@@
static void device_class_init(ObjectClass *class, void *data)
{
...
dc->hotpluggable = true;
+dc->user_creatable = true;
...
}
@@
@@
struct DeviceClass {
...
-bool cannot_instantiate_with_device_add_yet;
+bool user_creatable;
...
}
@@
expression DC;
@@
(
-!DC->cannot_instantiate_with_device_add_yet
+DC->user_creatable
|
-DC->cannot_instantiate_with_device_add_yet
+!DC->user_creatable
)
Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Thomas Huth <thuth@redhat.com>
Acked-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Acked-by: Marcel Apfelbaum <marcel@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170503203604.31462-2-ehabkost@redhat.com>
[ehabkost: kept "TODO remove once we're there" comment]
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
If, once the kernel has booted, we try to remove a memory
hotplugged while the kernel was not started, QEMU crashes on
an assert:
qemu-system-ppc64: hw/virtio/vhost.c:651:
vhost_commit: Assertion `r >= 0' failed.
...
#4 in vhost_commit
#5 in memory_region_transaction_commit
#6 in pc_dimm_memory_unplug
#7 in spapr_memory_unplug
#8 spapr_machine_device_unplug
#9 in hotplug_handler_unplug
#10 in spapr_lmb_release
#11 in detach
#12 in set_allocation_state
#13 in rtas_set_indicator
...
If we take a closer look to the guest kernel log, we can see when
we try to unplug the memory:
pseries-hotplug-mem: Attempting to hot-add 4 LMB(s)
What happens:
1- The kernel has ignored the memory hotplug event because
it was not started when it was generated.
2- When we hot-unplug the memory,
QEMU starts to remove the memory,
generates an hot-unplug event,
and signals the kernel of the incoming new event
3- as the kernel is started, on the QEMU signal, it reads
the event list, decodes the hotplug event and tries to
finish the hotplugging.
4- QEMU receive the the hotplug notification while it
is trying to hot-unplug the memory. This moves the memory
DRC to an invalid state
This patch prevents this by not allowing to set the allocation
state to USABLE while the DRC is awaiting release.
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1432382
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Fix the design flaw demonstrated in the previous commit: new method
check_list() lets input visitors report that unvisited input remains
for a list, exactly like check_struct() lets them report that
unvisited input remains for a struct or union.
Implement the method for the qobject input visitor (straightforward),
and the string input visitor (less so, due to the magic list syntax
there). The opts visitor's list magic is even more impenetrable, and
all I can do there today is a stub with a FIXME comment. No worse
than before.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1488544368-30622-26-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Michael Roth
Greg Kurz
Daniel Henrique Barboza
Bharata B Rao
Markus Armbruster
David Gibson
Laurent Vivier
Eduardo Habkost
Stefan Weil