The Real Mode Area (RMA) is the part of memory which a guest can access
when in real (MMU off) mode. Of course, for a guest under KVM, the MMU
isn't really turned off, it's just in a special translation mode - Virtual
Real Mode Area (VRMA) - which looks like real mode in guest mode.
The mechanics of how this works when using the hash MMU (HPT) put a
constraint on the size of the RMA, which depends on the size of the
HPT. So, the latter part of spapr_setup_hpt_and_vrma() clamps the RMA
we advertise to the guest based on this VRMA limit.
There are several things wrong with this:
1) spapr_setup_hpt_and_vrma() doesn't actually clamp, it takes the minimum
of Node 0 memory size and the VRMA limit. That will *often* work the
same as clamping, but there can be other constraints on RMA size which
supersede Node 0 memory size. We have real bugs caused by this
(currently worked around in the guest kernel)
2) Some callers of spapr_setup_hpt_and_vrma() are in a situation where
we're past the point that we can actually advertise an RMA limit to the
guest
3) But most fundamentally, the VRMA limit depends on host configuration
(page size) which shouldn't be visible to the guest, but this partially
exposes it. This can cause problems with migration in certain edge
cases, although we will mostly get away with it.
In practice, this clamping is almost never applied anyway. With 64kiB
pages and the normal rules for sizing of the HPT, the theoretical VRMA
limit will be 4x(guest memory size) and so never hit. It will hit with
4kiB pages, where it will be (guest memory size)/4. However all mainstream
distro kernels for POWER have used a 64kiB page size for at least 10 years.
So, simply replace this logic with a check that the RMA we've calculated
based only on guest visible configuration will fit within the host implied
VRMA limit. This can break if running HPT guests on a host kernel with
4kiB page size. As noted that's very rare. There also exist several
possible workarounds:
* Change the host kernel to use 64kiB pages
* Use radix MMU (RPT) guests instead of HPT
* Use 64kiB hugepages on the host to back guest memory
* Increase the guest memory size so that the RMA hits one of the fixed
limits before the RMA limit. This is relatively easy on POWER8 which
has a 16GiB limit, harder on POWER9 which has a 1TiB limit.
* Use a guest NUMA configuration which artificially constrains the RMA
within the VRMA limit (the RMA must always fit within Node 0).
Previously, on KVM, we also temporarily reduced the rma_size to 256M so
that the we'd load the kernel and initrd safely, regardless of the VRMA
limit. This was a) confusing, b) could significantly limit the size of
images we could load and c) introduced a behavioural difference between
KVM and TCG. So we remove that as well.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
If a hot plug or unplug request is pending at CAS, we currently trigger
a CAS reboot, which severely increases the guest boot time. This is
because SLOF doesn't handle hot plug events and we had no way to fix
the FDT that gets presented to the guest.
We can do better thanks to recent changes in QEMU and SLOF:
- we now return a full FDT to SLOF during CAS
- SLOF was fixed to correctly detect any device that was either added or
removed since boot time and to update its internal DT accordingly.
The right solution is to process all pending hot plug/unplug requests
during CAS: convert hot plugged devices to cold plugged devices and
remove the hot unplugged ones, which is exactly what spapr_drc_reset()
does. Also clear all hot plug events that are currently queued since
they're no longer relevant.
Note that SLOF cannot currently populate hot plugged PCI bridges or PHBs
at CAS. Until this limitation is lifted, SLOF will reset the machine when
this scenario occurs : this will allow the FDT to be fully processed when
SLOF is started again (ie. the same effect as the CAS reboot that would
occur anyway without this patch).
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158257222352.4102917.8984214333937947307.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We currently don't support hotplug of devices between boot and CAS. If
this happens a CAS reboot is triggered. We detect this during CAS using
the spapr_drc_needed() function which is essentially a VMStateDescription
.needed callback. Even if the condition for CAS reboot happens to be the
same as for DRC migration, it looks wrong to piggyback a migration helper
for this.
Introduce a helper with slightly more explicit name and use it in both CAS
and DRC migration code. Since a subsequent patch will enhance this helper
to cover the case of hot unplug, let's go for spapr_drc_transient(). While
here convert spapr_hotplugged_dev_before_cas() to the "transient" wording as
well.
This doesn't change any behaviour.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158169248180.3465937.9531405453362718771.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Use an explicit boolean type.
This commit was produced with the included Coccinelle script
scripts/coccinelle/exec_rw_const.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
According to the description of "ibm,client-architecture-support" that
can found in LoPAPR "B.6.2.3 Root Node Methods":
If multiple partition processors or threads are active at the time of
the ibm,client-architecture-support method call, or an error is detected
in the format of the ibm,architecture.vec structure, the err? boolean
shall be TRUE; else FALSE.
We certainly don't want to temper with the platform or with the PCR of
the other vCPUs if they happen to be active. Ensure we have only one
active vCPU and fail CAS otherwise. This is just for conformance and
robustness, it doesn't fix any known bugs.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <157969867170.571404.12117797348882189656.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Most of the option vector helpers have assertions to check their
arguments aren't null. The guest can provide an arbitrary address
for the CAS structure that would result in such null arguments.
Fail CAS with H_PARAMETER and print a warning instead of aborting
QEMU.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <157925255250.397143.10855183619366882459.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
spapr_ovec_diff(ov, old, new) has somewhat complex semantics. ov is set
to those bits which are in new but not old, and it returns as a boolean
whether or not there are any bits in old but not new.
It turns out that both callers only care about the second, not the first.
This is basically equivalent to a bitmap subset operation, which is easier
to understand and implement. So replace spapr_ovec_diff() with
spapr_ovec_subset().
Cc: Mike Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cedric Le Goater <clg@fr.ibm.com>
spapr_h_cas_compose_response() handles the last piece of the PAPR feature
negotiation process invoked via the ibm,client-architecture-support OF
call. Its only caller is h_client_architecture_support() which handles
most of the rest of that process.
I believe it was placed in a separate file originally to handle some
fiddly dependencies between functions, but mostly it's just confusing
to have the CAS process split into two pieces like this. Now that
compose response is simplified (by just generating the whole device
tree anew), it's cleaner to just fold it into
h_client_architecture_support().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cedric Le Goater <clg@fr.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
PAPR allows the interrupt controller used on a POWER9 machine (XICS or
XIVE) to be selected by the guest operating system, by using the
ibm,client-architecture-support (CAS) feature negotiation call.
Currently, if the guest selects an interrupt controller different from the
one selected at initial boot, this causes the system to be reset with the
new model and the boot starts again. This means we run through the SLOF
boot process twice, as well as any other bootloader (e.g. grub) in use
before the OS calls CAS. This can be confusing and/or inconvenient for
users.
Thanks to two fairly recent changes, we no longer need this reboot. 1) we
now completely regenerate the device tree when CAS is called (meaning we
don't need special case updates for all the device tree changes caused by
the interrupt controller mode change), 2) we now have explicit code paths
to activate and deactivate the different interrupt controllers, rather than
just implicitly calling those at machine reset time.
We can therefore eliminate the reboot for changing irq mode, simply by
putting a call to spapr_irq_update_active_intc() before we call
spapr_h_cas_compose_response() (which gives the updated device tree to
the guest firmware and OS).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cedric Le Goater <clg@fr.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
SpaprIrq::ov5 stores the value for a particular byte in PAPR option vector
5 which indicates whether XICS, XIVE or both interrupt controllers are
available. As usual for PAPR, the encoding is kind of overly complicated
and confusing (though to be fair there are some backwards compat things it
has to handle).
But to make our internal code clearer, have SpaprIrq encode more directly
which backends are available as two booleans, and derive the OV5 value from
that at the point we need it.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Certain old guest versions don't understand the radix MMU introduced with
POWER ISA 3.0, but incorrectly select it if presented with the option at
CAS time. We workaround this in qemu by explicitly excluding the radix
(and other ISA 3.0 linked) options if the guest doesn't explicitly note
support for ISA 3.0.
This is handled by the 'cas_legacy_guest_workaround' flag, which is pretty
vague. Rename it to 'cas_pre_isa3_guest' to be clearer about what it's for.
In addition, we unnecessarily call spapr_populate_pa_features() with
different options when initially constructing the device tree and when
adjusting it at CAS time. At the initial construct time cas_pre_isa3_guest
is already false, so we can still use the flag, rather than explicitly
overriding it to be false at the callsite.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
The sPAPR platform includes feature negotiation between the guest and
platform. That sometimes requires reconfiguring the virtual hardware, and
in some cases that is a complex enough process that we trigger a system
reset to handle it. That interacts badly with -no-reboot - we trigger the
reboot, -no-reboot means we exit and so the guest never gets to try again.
Eventually we want to get rid of CAS reboots entirely, since they're odd
and irritating for the user. But in the meantime we can fix the -no-reboot
problem by using SHUTDOWN_CAUSE_SUBSYSTEM_RESET which ignores -no-reboot
and seems to be designed for this sort of faux-reset for internal purposes
only.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This implements the H_TPM_COMM hypercall, which is used by an
Ultravisor to pass TPM commands directly to the host's TPM device, or
a TPM Resource Manager associated with the device.
This also introduces a new virtual device, spapr-tpm-proxy, which
is used to configure the host TPM path to be used to service
requests sent by H_TPM_COMM hcalls, for example:
-device spapr-tpm-proxy,id=tpmp0,host-path=/dev/tpmrm0
By default, no spapr-tpm-proxy will be created, and hcalls will return
H_FUNCTION.
The full specification for this hypercall can be found in
docs/specs/ppc-spapr-uv-hcalls.txt
Since SVM-related hcalls like H_TPM_COMM use a reserved range of
0xEF00-0xEF80, we introduce a separate hcall table here to handle
them.
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com
Message-Id: <20190717205842.17827-3-mdroth@linux.vnet.ibm.com>
[dwg: Corrected #include for upstream change]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This has been useful to modify and test the Linux pseries suspend
code but it requires modification to the guest to call it (due to
being gated by other unimplemented features). It is not otherwise
used by Linux yet, but work is slowly progressing there.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190718034214.14948-5-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This does not do directed yielding and is not quite as strict as PAPR
specifies in terms of precise dispatch behaviour. This generally will
mean suboptimal performance, rather than guest misbehaviour. Linux
does not rely on exact dispatch behaviour.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190718034214.14948-4-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
H_PROD is added, and H_CEDE is modified to test the prod bit
according to PAPR.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190718034214.14948-3-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Implement cpu_exec_enter/exit on ppc which calls into new methods of
the same name in PPCVirtualHypervisorClass. These are used by spapr
to implement the splpar VPA dispatch counter initially.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190718034214.14948-2-npiggin@gmail.com>
[dwg: Removed unnecessary CONFIG_USER_ONLY checks as suggested by gkurz]
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Free all SpaprOptionVector local pointers after use.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <156335160761.82682.11912058325777251614.stgit@lep8c.aus.stglabs.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
sysemu/sysemu.h is a rather unfocused dumping ground for stuff related
to the system-emulator. Evidence:
* It's included widely: in my "build everything" tree, changing
sysemu/sysemu.h still triggers a recompile of some 1100 out of 6600
objects (not counting tests and objects that don't depend on
qemu/osdep.h, down from 5400 due to the previous two commits).
* It pulls in more than a dozen additional headers.
Split stuff related to run state management into its own header
sysemu/runstate.h.
Touching sysemu/sysemu.h now recompiles some 850 objects. qemu/uuid.h
also drops from 1100 to 850, and qapi/qapi-types-run-state.h from 4400
to 4200. Touching new sysemu/runstate.h recompiles some 500 objects.
Since I'm touching MAINTAINERS to add sysemu/runstate.h anyway, also
add qemu/main-loop.h.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-30-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[Unbreak OS-X build]
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h). It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.
Include qemu/main-loop.h only where it's needed. Touching it now
recompiles only some 1700 objects. For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the
others, they shrink only slightly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Let's suggest to the user how the machine should be configured to allow
the guest to boot successfully.
Suggested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155799221739.527449.14907564571096243745.stgit@bahia.lan>
Reviewed-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
[dwg: Adjusted for style error]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
If a machine is started with ic-mode=xive but the guest only knows
about XICS, eg. an RHEL 7.6 guest, the kernel panics. This is
expected but a bit unfortunate since the crash doesn't provide
much information for the end user to guess what's happening.
Detect that during CAS and exit QEMU with a proper error message
instead, like it is already done for the MMU.
Even if this is less likely to happen, the opposite case of a guest
that only knows about XIVE would certainly fail all the same if the
machine is started with ic-mode=xics.
Also, the only valid values a guest can pass in byte 23 of OV5 during
CAS are 0b00 (XIVE legacy mode) and 0b01 (XIVE exploitation mode). Any
other value is a bug, at least with the current spec. Again, it does
not seem right to let the guest go on without a precise idea of the
interrupt mode it asked for.
Handle these cases as well.
Reported-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155793986451.464434.12887933000007255549.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
With MT-TCG, we are now running translation in a racy way, thus
we need to mimic hardware when it comes to updating the R and
C bits, by doing byte stores.
The current "store_hpte" abstraction is ill suited for this, we
replace it with two separate callbacks for setting R and C.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190411080004.8690-4-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190411080004.8690-3-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
176dccee "target/ppc/spapr: Clear partition table entry when allocating
hash table" reworked the H_REGISTER_PROCESS_TABLE hypercall, but
unfortunately due to a small error no longer correctly sets the LPCR[GTSE]
bit which allows the guest to directly execute (some types of) tlbie (TLB
flush) instructions without involving the hypervisor.
We got away with this, initially, because POWER9 did not have hypervisor
mode enabled in its msr_mask, which meant we didn't actually run hypervisor
privilege checks in TCG at all. However, da874d90 "target/ppc: add HV
support for POWER9" turned on HV support on POWER9 for the benefit of the
powernv machine type.
This exposed the earlier bug in H_REGISTER_PROCESS_TABLE, and causes guests
which rely on LPCR[GTSE] (i.e. basically all of them) to crash during early
boot when their first tlbie instruction causes an unexpected trap.
Fixes: 176dccee target/ppc/spapr: Clear partition table entry when allocating hash table
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Cleber Rosa <crosa@redhat.com>
The qemu coding standard is to use CamelCase for type and structure names,
and the pseries code follows that... sort of. There are quite a lot of
places where we bend the rules in order to preserve the capitalization of
internal acronyms like "PHB", "TCE", "DIMM" and most commonly "sPAPR".
That was a bad idea - it frequently leads to names ending up with hard to
read clusters of capital letters, and means they don't catch the eye as
type identifiers, which is kind of the point of the CamelCase convention in
the first place.
In short, keeping type identifiers look like CamelCase is more important
than preserving standard capitalization of internal "words". So, this
patch renames a heap of spapr internal type names to a more standard
CamelCase.
In addition to case changes, we also make some other identifier renames:
VIOsPAPR* -> SpaprVio*
The reverse word ordering was only ever used to mitigate the capital
cluster, so revert to the natural ordering.
VIOsPAPRVTYDevice -> SpaprVioVty
VIOsPAPRVLANDevice -> SpaprVioVlan
Brevity, since the "Device" didn't add useful information
sPAPRDRConnector -> SpaprDrc
sPAPRDRConnectorClass -> SpaprDrcClass
Brevity, and makes it clearer this is the same thing as a "DRC"
mentioned in many other places in the code
This is 100% a mechanical search-and-replace patch. It will, however,
conflict with essentially any and all outstanding patches touching the
spapr code.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
If we allocate a hash page table then we know that the guest won't be
using process tables, so set the partition table entry maintained for
the guest to zero. If this isn't done, then the guest radix bit will
remain set in the entry. This means that when the guest calls
H_REGISTER_PROCESS_TABLE there will be a mismatch between then flags
and the value in spapr->patb_entry, and the call will fail. The guest
will then panic:
Failed to register process table (rc=-4)
kernel BUG at arch/powerpc/platforms/pseries/lpar.c:959
The result being that it isn't possible to boot a hash guest on a P9
system.
Also fix a bug in the flags parsing in h_register_process_table() which
was introduced by the same patch, and simplify the handling to make it
less likely that errors will be introduced in the future. The effect
would have been setting the host radix bit LPCR_HR for a hash guest
using process tables, which currently isn't supported and so couldn't
have been triggered.
Fixes: 00fd075e18 "target/ppc/spapr: Set LPCR:HR when using Radix mode"
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190305022102.17610-1-sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Introduce a new spapr_cap SPAPR_CAP_CCF_ASSIST to be used to indicate
the requirement for a hw-assisted version of the count cache flush
workaround.
The count cache flush workaround is a software workaround which can be
used to flush the count cache on context switch. Some revisions of
hardware may have a hardware accelerated flush, in which case the
software flush can be shortened. This cap is used to set the
availability of such hardware acceleration for the count cache flush
routine.
The availability of such hardware acceleration is indicated by the
H_CPU_CHAR_BCCTR_FLUSH_ASSIST flag being set in the characteristics
returned from the KVM_PPC_GET_CPU_CHAR ioctl.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301031912.28809-2-sjitindarsingh@gmail.com>
[dwg: Small style fixes]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The spapr_cap SPAPR_CAP_IBS is used to indicate the level of capability
for mitigations for indirect branch speculation. Currently the available
values are broken (default), fixed-ibs (fixed by serialising indirect
branches) and fixed-ccd (fixed by diabling the count cache).
Introduce a new value for this capability denoted workaround, meaning that
software can work around the issue by flushing the count cache on
context switch. This option is available if the hypervisor sets the
H_CPU_BEHAV_FLUSH_COUNT_CACHE flag in the cpu behaviours returned from
the KVM_PPC_GET_CPU_CHAR ioctl.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301031912.28809-1-sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
That "b" means "base address" and thus shouldn't be in the name
of actual entries and related constants.
This patch keeps the synthetic patb_entry field of the spapr
virtual hypervisor unchanged until I figure out if that has
an impact on the migration stream.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190215170029.15641-11-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The HW relies on LPCR:HR along with the PATE to determine whether
to use Radix or Hash mode. In fact it uses LPCR:HR more commonly
than the PATE.
For us, it's also more efficient to do so, especially since unlike
the HW we do not maintain a cache of the current PATE and HV PATE
in a generic place.
Prepare the grounds for that by ensuring that LPCR:HR is set
properly on SPAPR machines.
Another option would have been to use a callback to get the PATE
but this gets messy when implementing bare metal support, it's
much simpler (and faster) to use LPCR.
Since existing migration streams may not have it, fix it up in
spapr_post_load() as well based on the pseudo-PATE entry that
we keep.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190215170029.15641-2-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The 'dual' sPAPR IRQ backend supports both interrupt mode, XIVE
exploitation mode and the legacy compatibility mode (XICS). both modes
are not supported at the same time.
The machine starts with the legacy mode and a new interrupt mode can
then be negotiated by the CAS process. In this case, the new mode is
activated after a reset to take into account the required changes in
the machine. These impact the device tree layout, the interrupt
presenter object and the exposed MMIO regions in the case of XIVE.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
SLOF receives a device tree and updates it with various properties
before switching to the guest kernel and QEMU is not aware of any changes
made by SLOF. Since there is no real RTAS (QEMU implements it), it makes
sense to pass the SLOF final device tree to QEMU to let it implement
RTAS related tasks better, such as PCI host bus adapter hotplug.
Specifially, now QEMU can find out the actual XICS phandle (for PHB
hotplug) and the RTAS linux,rtas-entry/base properties (for firmware
assisted NMI - FWNMI).
This stores the initial DT blob in the sPAPR machine and replaces it
in the KVMPPC_H_UPDATE_DT (new private hypercall) handler.
This adds an @update_dt_enabled machine property to allow backward
migration.
SLOF already has a hypercall since
https://github.com/aik/SLOF/commit/e6fc84652c9c0073f9183
This makes use of the new fdt_check_full() helper. In order to allow
the configure script to pick the correct DTC version, this adjusts
the DTC presense test.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-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>
H_HOME_NODE_ASSOCIATIVITY H-Call returns the associativity domain
designation associated with the identifier input parameter
This fixes a crash when we try to hotplug a CPU in memory-less and
CPU-less numa node. In this case, the kernel tries to online the
node, but without the information provided by this h-call, the node id,
it cannot and the CPU is started while the node is not onlined.
It also removes the warning message from the kernel:
VPHN is not supported. Disabling polling..
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
CPUPPCState currently contains a number of fields containing the state of
the VPA. The VPA is a PAPR specific concept covering several guest/host
shared memory areas used to communicate some information with the
hypervisor.
As a PAPR concept this is really machine specific information, although it
is per-cpu, so it doesn't really belong in the core CPU state structure.
There's also other information that's per-cpu, but platform/machine
specific. So create a (void *)machine_data in PowerPCCPU which can be
used by the machine to locate per-cpu data. Intialization, lifetime and
cleanup of machine_data is entirely up to the machine type.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
If the negotiated compat mode can't be set, but raw mode is supported,
we decide to ignore the error. An so, we should free it to prevent a
memory leak.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Rename it to better match the new terminology.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-9-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Let's allow to query the MemoryHotplugState directly from the machine.
If the pointer is NULL, the machine does not support memory devices. If
the pointer is !NULL, the machine supports memory devices and the
data structure contains information about the applicable physical
guest address space region.
This allows us to generically detect if a certain machine has support
for memory devices, and to generically manage it (find free address
range, plug/unplug a memory region).
We will rename "MemoryHotplugState" to something more meaningful
("DeviceMemory") after we completed factoring out the pc-dimm code into
MemoryDevice code.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-3-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
[ehabkost: rebased series, solved conflicts at spapr.c]
[ehabkost: squashed fix to use g_malloc0()]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
On the qmp level, we already have the concept of memory devices:
"query-memory-devices"
Right now, we only support NVDIMM and PCDIMM.
We want to map other devices later into the address space of the guest.
Such device could e.g. be virtio devices. These devices will have a
guest memory range assigned but won't be exposed via e.g. ACPI. We want
to make them look like memory device, but not glued to pc-dimm.
Especially, it will not always be possible to have TYPE_PC_DIMM as a parent
class (e.g. virtio devices). Let's use an interface instead. As a first
part, convert handling of
- qmp_pc_dimm_device_list
- get_plugged_memory_size
to our new model. plug/unplug stuff etc. will follow later.
A memory device will have to provide the following functions:
- get_addr(): Necessary, as the property "addr" can e.g. not be used for
virtio devices (already defined).
- get_plugged_size(): The amount this device offers to the guest as of
now.
- get_region_size(): Because this can later on be bigger than the
plugged size.
- fill_device_info(): Fill MemoryDeviceInfo, e.g. for qmp.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-2-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
There are several places in spapr_hcall.c where we need to update the LPCR
value on all CPUs. We do this with the set_spr() helper. That's not
really correct because this directly sets the SPR value, without going
through the ppc_store_lpcr() helper which may need to update state based
on the LPCR change.
In fact, set_spr() is only ever used for the LPCR, so replace it with an
explicit LPCR updated which uses the right low-level helper. While we're
there, move the CPU_FOREACH() which was in every one of the callers into
the new helper: set_all_lpcrs().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Convert cap-ibs (indirect branch speculation) to a custom spapr-cap
type.
All tristate caps have now been converted to custom spapr-caps, so
remove the remaining support for them.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
[dwg: Don't explicitly list "?"/help option, trust convention]
[dwg: Fold tristate removal into here, to not break bisect]
[dwg: Fix minor style problems]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Newer kernels have a htab resize capability when adding or remove
memory. At these situations, the guest kernel might reallocate its
htab to a more suitable size based on the resulting memory.
However, we're not setting the new value back into the machine state
when a KVM guest resizes its htab. At first this doesn't seem harmful,
but when migrating or saving the guest state (via virsh managedsave,
for instance) this mismatch between the htab size of QEMU and the
kernel makes the guest hangs when trying to load its state.
Inside h_resize_hpt_commit, the hypercall that commits the hash page
resize changes, let's set spapr->htab_shift to the new value if we're
sure that kvmppc_resize_hpt_commit were successful.
While we're here, add a "not RADIX" sanity check as it is already done
in the related hypercall h_resize_hpt_prepare.
Fixes: https://github.com/open-power-host-os/qemu/issues/28
Reported-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit bcb5ce08cf ("spapr: Rename machine init functions for clarity")
renamed ppc_spapr_reset to spapr_machine_reset and ppc_spapr_init
to spapr_machine_init. Let's also rename the references in
comments.
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Detected by Coverity (CID 1385702). This fixes the recently added hypercall
to let guests properly apply Spectre and Meltdown workarounds.
Fixes: c59704b254 "target/ppc/spapr: Add H-Call H_GET_CPU_CHARACTERISTICS"
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The new H-Call H_GET_CPU_CHARACTERISTICS is used by the guest to query
behaviours and available characteristics of the cpu.
Implement the handler for this new H-Call which formulates its response
based on the setting of the spapr_caps cap-cfpc, cap-sbbc and cap-ibs.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
applied using ./scripts/clean-includes
not needed since 7ebaf79556
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
KVM HV will soon support running a guest in hash mode on a POWER9 host
running in radix mode (see [1]), however the guest currently fails to
boot.
This is because the "htab_shift" value (the size of the MMU's hash
table) is added to the device tree before KVM has had a chance to
change it. If the host is in hash mode, KVM does not need to change it
and so the problem is not seen, but when the host is in radix mode a
change is required and we see a problem.
To fix this, move the call spapr_setup_hpt_and_vrma() (where
htab_shift could be changed) up a little so that it's called before
spapr_h_cas_compose_response() (where htab_shift is added to the
device tree).
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
[1] See http://www.spinics.net/lists/kvm-ppc/msg13057.html
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
In order to prevent the guest from forcing the allocation of large amounts
of qemu memory (or host kernel memory, in the case of KVM HV), we limit
the size of Hashed Page Table (HPT) it is allowed to allocated, based on
its RAM size.
However, the current calculation is not correct: it only adds up the size
of plugged memory, ignoring the base memory size. This patch corrects it.
While we're there, use get_plugged_memory_size() instead of directly
calling pc_existing_dimms_capacity(). The only difference is that it
will abort on failure, which is right: a failure here indicates something
wrong within qemu.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
