Commit Graph

272 Commits

Author SHA1 Message Date
Nicholas Piggin
edfdbf9c6b ppc/spapr: Add FWNMI System Reset state
The FWNMI option must deliver system reset interrupts to their
registered address, and there are a few constraints on the handler
addresses specified in PAPR. Add the system reset address state and
checks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-4-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviwed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
8af7e1fe6f ppc/spapr: Change FWNMI names
The option is called "FWNMI", and it involves more than just machine
checks, also machine checks can be delivered without the FWNMI option,
so re-name various things to reflect that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-3-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Alexey Kardashevskiy
4dba872219 spapr/rtas: Reserve space for RTAS blob and log
At the moment SLOF reserves space for RTAS and instantiates the RTAS blob
which is 20 bytes binary blob calling an hypercall. The rest of the RTAS
area is a log which SLOF has no idea about but QEMU does.

This moves RTAS sizing to QEMU and this overrides the size from SLOF.
The only remaining problem is that SLOF copies the number of bytes it
reserved (2KB for now) so QEMU needs to reserve at least this much;
SLOF will be fixed separately to check that rtas-size from QEMU is
enough for those 20 bytes for the H_RTAS hcall.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20200316011841.99970-1-aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 15:08:50 +11:00
David Gibson
1052ab67f4 spapr: Don't clamp RMA to 16GiB on new machine types
In spapr_machine_init() we clamp the size of the RMA to 16GiB and the
comment saying why doesn't make a whole lot of sense.  In fact, this was
done because the real mode handling code elsewhere limited the RMA in TCG
mode to the maximum value configurable in LPCR[RMLS], 16GiB.

But,
 * Actually LPCR[RMLS] has been able to encode a 256GiB size for a very
   long time, we just didn't implement it properly in the softmmu
 * LPCR[RMLS] shouldn't really be relevant anyway, it only was because we
   used to abuse the RMOR based translation mode in order to handle the
   fact that we're not modelling the hypervisor parts of the cpu

We've now removed those limitations in the modelling so the 16GiB clamp no
longer serves a function.  However, we can't just remove the limit
universally: that would break migration to earlier qemu versions, where
the 16GiB RMLS limit still applies, no matter how bad the reasons for it
are.

So, we replace the 16GiB clamp, with a clamp to a limit defined in the
machine type class.  We set it to 16 GiB for machine types 4.2 and earlier,
but set it to 0 meaning unlimited for the new 5.0 machine type.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-03-17 09:41:15 +11:00
David Gibson
8897ea5a9f spapr: Don't attempt to clamp RMA to VRMA constraint
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>
2020-03-17 09:41:15 +11:00
Greg Kurz
ad334d89a6 spapr: Handle pending hot plug/unplug requests at CAS
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>
2020-03-17 09:41:14 +11:00
Alexey Kardashevskiy
87262806cb spapr: Allow changing offset for -kernel image
This allows moving the kernel in the guest memory. The option is useful
for step debugging (as Linux is linked at 0x0); it also allows loading
grub which is normally linked to run at 0x20000.

This uses the existing kernel address by default.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20200203032943.121178-6-aik@ozlabs.ru>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-21 09:15:04 +11:00
Shivaprasad G Bhat
b5fca656f7 spapr: Add Hcalls to support PAPR NVDIMM device
This patch implements few of the necessary hcalls for the nvdimm support.

PAPR semantics is such that each NVDIMM device is comprising of multiple
SCM(Storage Class Memory) blocks. The guest requests the hypervisor to
bind each of the SCM blocks of the NVDIMM device using hcalls. There can
be SCM block unbind requests in case of driver errors or unplug(not
supported now) use cases. The NVDIMM label read/writes are done through
hcalls.

Since each virtual NVDIMM device is divided into multiple SCM blocks,
the bind, unbind, and queries using hcalls on those blocks can come
independently. This doesn't fit well into the qemu device semantics,
where the map/unmap are done at the (whole)device/object level granularity.
The patch doesnt actually bind/unbind on hcalls but let it happen at the
device_add/del phase itself instead.

The guest kernel makes bind/unbind requests for the virtual NVDIMM device
at the region level granularity. Without interleaving, each virtual NVDIMM
device is presented as a separate guest physical address range. So, there
is no way a partial bind/unbind request can come for the vNVDIMM in a
hcall for a subset of SCM blocks of a virtual NVDIMM. Hence it is safe to
do bind/unbind everything during the device_add/del.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <158131059899.2897.11515211602702956854.stgit@lep8c.aus.stglabs.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-21 09:15:04 +11:00
Aravinda Prasad
2500fb423a migration: Include migration support for machine check handling
This patch includes migration support for machine check
handling. Especially this patch blocks VM migration
requests until the machine check error handling is
complete as these errors are specific to the source
hardware and is irrelevant on the target hardware.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[Do not set FWNMI cap in post_load, now its done in .apply hook]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Message-Id: <20200130184423.20519-7-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:11 +11:00
Aravinda Prasad
f03496bc12 ppc: spapr: Handle "ibm,nmi-register" and "ibm,nmi-interlock" RTAS calls
This patch adds support in QEMU to handle "ibm,nmi-register"
and "ibm,nmi-interlock" RTAS calls.

The machine check notification address is saved when the
OS issues "ibm,nmi-register" RTAS call.

This patch also handles the case when multiple processors
experience machine check at or about the same time by
handling "ibm,nmi-interlock" call. In such cases, as per
PAPR, subsequent processors serialize waiting for the first
processor to issue the "ibm,nmi-interlock" call. The second
processor that also received a machine check error waits
till the first processor is done reading the error log.
The first processor issues "ibm,nmi-interlock" call
when the error log is consumed.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[Register fwnmi RTAS calls in core_rtas_register_types()
 where other RTAS calls are registered]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Message-Id: <20200130184423.20519-6-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:11 +11:00
Aravinda Prasad
81fe70e443 target/ppc: Build rtas error log upon an MCE
Upon a machine check exception (MCE) in a guest address space,
KVM causes a guest exit to enable QEMU to build and pass the
error to the guest in the PAPR defined rtas error log format.

This patch builds the rtas error log, copies it to the rtas_addr
and then invokes the guest registered machine check handler. The
handler in the guest takes suitable action(s) depending on the type
and criticality of the error. For example, if an error is
unrecoverable memory corruption in an application inside the
guest, then the guest kernel sends a SIGBUS to the application.
For recoverable errors, the guest performs recovery actions and
logs the error.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[Assume SLOF has allocated enough room for rtas error log]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20200130184423.20519-5-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:10 +11:00
Aravinda Prasad
9ac703ac5f target/ppc: Handle NMI guest exit
Memory error such as bit flips that cannot be corrected
by hardware are passed on to the kernel for handling.
If the memory address in error belongs to guest then
the guest kernel is responsible for taking suitable action.
Patch [1] enhances KVM to exit guest with exit reason
set to KVM_EXIT_NMI in such cases. This patch handles
KVM_EXIT_NMI exit.

[1] https://www.spinics.net/lists/kvm-ppc/msg12637.html
    (e20bbd3d and related commits)

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200130184423.20519-4-ganeshgr@linux.ibm.com>
[dwg: #ifdefs to fix compile for 32-bit target]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:10 +11:00
Aravinda Prasad
9d953ce447 ppc: spapr: Introduce FWNMI capability
Introduce fwnmi an spapr capability and add a helper function
which tries to enable it, which would be used by following patch
of the series. This patch by itself does not change the existing
behavior.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[eliminate cap_ppc_fwnmi, add fwnmi cap to migration state
 and reprhase the commit message]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20200130184423.20519-3-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:10 +11:00
David Gibson
0c21e07354 spapr: Fold h_cas_compose_response() into h_client_architecture_support()
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>
2019-12-17 10:39:48 +11:00
David Gibson
54255c1f65 spapr: Move SpaprIrq::nr_xirqs to SpaprMachineClass
For the benefit of peripheral device allocation, the number of available
irqs really wants to be the same on a given machine type version,
regardless of what irq backends we are using.  That's the case now, but
only because we make sure the different SpaprIrq instances have the same
value except for the special legacy one.

Since this really only depends on machine type version, move the value to
SpaprMachineClass instead of SpaprIrq.  This also puts the code to set it
to the lower value on old machine types right next to setting
legacy_irq_allocation, which needs to go hand in hand.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2019-10-24 09:36:55 +11:00
David Gibson
81106ddd1a spapr: Formalize notion of active interrupt controller
spapr now has the mechanism of constructing both XICS and XIVE instances of
the SpaprInterruptController interface.  However, only one of the interrupt
controllers will actually be active at any given time, depending on feature
negotiation with the guest.  This is handled in the current code via
spapr_irq_current() which checks the OV5 vector from feature negotiation to
determine the current backend.

Determining the active controller at the point we need it like this
can be pretty confusing, because it makes it very non obvious at what
points the active controller can change.  This can make it difficult
to reason about the code and where a change of active controller could
appear in sequence with other events.

Make this mechanism more explicit by adding an 'active_intc' pointer
and an explicit spapr_irq_update_active_intc() function to update it
from the CAS state.  We also add hooks on the intc backend which will
get called when it is activated or deactivated.

For now we just introduce the switch and hooks, later patches will
actually start using them.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2019-10-24 09:36:55 +11:00
Greg Kurz
29cb418749 spapr: Set VSMT to smp_threads by default
Support for setting VSMT is available in KVM since linux-4.13. Most distros
that support KVM on POWER already have it. It thus seem reasonable enough
to have the default machine to set VSMT to smp_threads.

This brings contiguous VCPU ids and thus brings their upper bound down to
the machine's max_cpus. This is especially useful for XIVE KVM devices,
which may thus allocate only one VP descriptor per VCPU.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <157010411885.246126.12610015369068227139.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-10-24 09:36:55 +11:00
Alexey Kardashevskiy
744a928cce spapr: Stop providing RTAS blob
SLOF implements one itself so let's remove it from QEMU. It is one less
image and simpler setup as the RTAS blob never stays in its initial place
anyway as the guest OS always decides where to put it.

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>
2019-10-04 10:25:23 +10:00
David Gibson
daa36379ce spapr: Simplify handling of pre ISA 3.0 guest workaround handling
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>
2019-10-04 10:25:23 +10:00
Alexey Kardashevskiy
6c3829a265 spapr_pci: Advertise BAR reallocation capability
The pseries guests do not normally allocate PCI resources and rely on
the system firmware doing so. Furthermore at least at some point in
the past the pseries guests won't even allowed to change BARs, probably
it is still the case for phyp. So since the initial commit we have [1]
which prevents resource reallocation.

This is not a problem until we want specific BAR alignments, for example,
PAGE_SIZE==64k to make sure we can still map MMIO BARs directly. For
the boot time devices we handle this in SLOF [2] but since QEMU's RTAS
does not allocate BARs, the guest does this instead and does not align
BARs even if Linux is given pci=resource_alignment=16@pci:0:0 as
PCI_PROBE_ONLY makes Linux ignore alignment requests.

ARM folks added a dial to control PCI_PROBE_ONLY via the device tree [3].
This makes use of the dial to advertise to the guest that we can handle
BAR reassignments. This limits the change to the latest pseries machine
to avoid old guests explosion.

We do not remove the flag from [1] as pseries guests are still supported
under phyp so having that removed may cause problems.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/platforms/pseries/setup.c?h=v5.1#n773
[2] https://git.qemu.org/?p=SLOF.git;a=blob;f=board-qemu/slof/pci-phb.fs;h=06729bcf77a0d4e900c527adcd9befe2a269f65d;hb=HEAD#l338
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f81c11af
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20190719043734.108462-1-aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-08-29 09:46:07 +10:00
Nicholas Piggin
93eac7b8f4 spapr: Implement ibm,suspend-me
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.

This allows a (lightly modified) guest kernel to suspend with
`echo mem > /sys/power/state` and be resumed with system_wakeup
monitor command.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190722061752.22114-2-npiggin@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-08-21 17:17:39 +10:00
Michael Roth
0fb6bd0732 spapr: initial implementation for H_TPM_COMM/spapr-tpm-proxy
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>
2019-08-21 17:17:12 +10:00
Nicholas Piggin
03ef074c04 spapr: Implement dispatch tracking for tcg
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>
2019-08-21 17:17:11 +10:00
Greg Kurz
d9293c4843 xics/spapr: Register RTAS/hypercalls once at machine init
QEMU may crash when running a spapr machine in 'dual' interrupt controller
mode on some older (but not that old, eg. ubuntu 18.04.2) KVMs with partial
XIVE support:

qemu-system-ppc64: hw/ppc/spapr_rtas.c:411: spapr_rtas_register:
 Assertion `!name || !rtas_table[token].name' failed.

XICS is controlled by the guest thanks to a set of RTAS calls. Depending
on whether KVM XICS is used or not, the RTAS calls are handled by KVM or
QEMU. In both cases, QEMU needs to expose the RTAS calls to the guest
through the "rtas" node of the device tree.

The spapr_rtas_register() helper takes care of all of that: it adds the
RTAS call token to the "rtas" node and registers a QEMU callback to be
invoked when the guest issues the RTAS call. In the KVM XICS case, QEMU
registers a dummy callback that just prints an error since it isn't
supposed to be invoked, ever.

Historically, the XICS controller was setup during machine init and
released during final teardown. This changed when the 'dual' interrupt
controller mode was added to the spapr machine: in this case we need
to tear the XICS down and set it up again during machine reset. The
crash happens because we indeed have an incompatibility with older
KVMs that forces QEMU to fallback on emulated XICS, which tries to
re-registers the same RTAS calls.

This could be fixed by adding proper rollback that would unregister
RTAS calls on error. But since the emulated RTAS calls in QEMU can
now detect when they are mistakenly called while KVM XICS is in
use, it seems simpler to register them once and for all at machine
init. This fixes the crash and allows to remove some now useless
lines of code.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <156044429963.125694.13710679451927268758.stgit@bahia.lab.toulouse-stg.fr.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-07-02 09:43:58 +10:00
Greg Kurz
3725ef1a94 spapr: Don't migrate the hpt_maxpagesize cap to older machine types
Commit 0b8c89be7f7b added the hpt_maxpagesize capability to the migration
stream. This is okay for new machine types but it breaks backward migration
to older QEMUs, which don't expect the extra subsection.

Add a compatibility boolean flag to the sPAPR machine class and use it to
skip migration of the capability for machine types 4.0 and older. This
fixes migration to an older QEMU. Note that the destination will emit a
warning:

qemu-system-ppc64: warning: cap-hpt-max-page-size lower level (16) in incoming stream than on destination (24)

This is expected and harmless though. It is okay to migrate from a lower
HPT maximum page size (64k) to a greater one (16M).

Fixes: 0b8c89be7f7b "spapr: Add forgotten capability to migration stream"
Based-on: <20190522074016.10521-3-clg@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155853262675.1158324.17301777846476373459.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-05-29 11:39:47 +10:00
David Gibson
64d4a53431 spapr: Add forgotten capability to migration stream
spapr machine capabilities are supposed to be sent in the migration stream
so that we can sanity check the source and destination have compatible
configuration.  Unfortunately, when we added the hpt-max-page-size
capability, we forgot to add it to the migration state.  This means that we
can generate spurious warnings when both ends are configured for large
pages, or potentially fail to warn if the source is configured for huge
pages, but the destination is not.

Fixes: 2309832afd "spapr: Maximum (HPT) pagesize property"

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2019-05-29 11:39:45 +10:00
Benjamin Herrenschmidt
a2dd4e83e7 ppc/hash64: Rework R and C bit updates
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>
2019-04-26 11:37:57 +10:00
Cédric Le Goater
64db6c70dc spapr/rtas: modify spapr_rtas_register() to remove RTAS handlers
Removing RTAS handlers will become necessary when the new pseries
machine supporting multiple interrupt mode is introduced.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190321144914.19934-9-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-04-26 10:41:23 +10:00
Alexey Kardashevskiy
ec132efaa8 spapr: Support NVIDIA V100 GPU with NVLink2
NVIDIA V100 GPUs have on-board RAM which is mapped into the host memory
space and accessible as normal RAM via an NVLink bus. The VFIO-PCI driver
implements special regions for such GPUs and emulates an NVLink bridge.
NVLink2-enabled POWER9 CPUs also provide address translation services
which includes an ATS shootdown (ATSD) register exported via the NVLink
bridge device.

This adds a quirk to VFIO to map the GPU memory and create an MR;
the new MR is stored in a PCI device as a QOM link. The sPAPR PCI uses
this to get the MR and map it to the system address space.
Another quirk does the same for ATSD.

This adds additional steps to sPAPR PHB setup:

1. Search for specific GPUs and NPUs, collect findings in
sPAPRPHBState::nvgpus, manage system address space mappings;

2. Add device-specific properties such as "ibm,npu", "ibm,gpu",
"memory-block", "link-speed" to advertise the NVLink2 function to
the guest;

3. Add "mmio-atsd" to vPHB to advertise the ATSD capability;

4. Add new memory blocks (with extra "linux,memory-usable" to prevent
the guest OS from accessing the new memory until it is onlined) and
npuphb# nodes representing an NPU unit for every vPHB as the GPU driver
uses it for link discovery.

This allocates space for GPU RAM and ATSD like we do for MMIOs by
adding 2 new parameters to the phb_placement() hook. Older machine types
set these to zero.

This puts new memory nodes in a separate NUMA node to as the GPU RAM
needs to be configured equally distant from any other node in the system.
Unlike the host setup which assigns numa ids from 255 downwards, this
adds new NUMA nodes after the user configures nodes or from 1 if none
were configured.

This adds requirement similar to EEH - one IOMMU group per vPHB.
The reason for this is that ATSD registers belong to a physical NPU
so they cannot invalidate translations on GPUs attached to another NPU.
It is guaranteed by the host platform as it does not mix NVLink bridges
or GPUs from different NPU in the same IOMMU group. If more than one
IOMMU group is detected on a vPHB, this disables ATSD support for that
vPHB and prints a warning.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for vfio portions]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Message-Id: <20190312082103.130561-1-aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-04-26 10:41:23 +10:00
David Gibson
0a794529bd spapr: Simplify handling of host-serial and host-model values
27461d69a0 "ppc: add host-serial and host-model machine attributes
(CVE-2019-8934)" introduced 'host-serial' and 'host-model' machine
properties for spapr to explicitly control the values advertised to the
guest in device tree properties with the same names.

The previous behaviour on KVM was to unconditionally populate the device
tree with the real host serial number and model, which leaks possibly
sensitive information about the host to the guest.

To maintain compatibility for old machine types, we allowed those props
to be set to "passthrough" to take the value from the host as before.  Or
they could be set to "none" to explicitly omit the device tree items.

Special casing specific values on what's otherwise a user supplied string
is very ugly.  So, this patch simplifies things by implementing the
backwards compatibility in a different way: we have a machine class flag
set for the older machines, and we only load the host values into the
device tree if A) they're not set by the user and B) we have that flag set.

This does mean that the "passthrough" functionality is no longer available
with the current machine type.  That's ok though: if a user or management
layer really wants the information passed through they can read it
themselves (OpenStack Nova already does something similar for x86).

It also means the user can't explicitly ask for the values to be omitted
on the old machine types.  I think that's an acceptable trade-off: if you
care enough about not leaking the host information you can either move to
the new machine type, or use a dummy value for the properties.

For the new machine type, this also removes an odd inconsistency
between running on a POWER and non-POWER (or non-Linux) hosts: if the
host information couldn't be read from where we expect (in the host's
device tree as exposed by Linux), we'd fallback to omitting the guest
device tree items.

While we're there, improve some poorly worded comments, and the help text
for the properties.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
2019-03-29 10:25:50 +11:00
David Gibson
ce2918cbc3 spapr: Use CamelCase properly
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>
2019-03-12 14:33:05 +11:00
Alexey Kardashevskiy
5f36666722 spapr_iommu: Do not replay mappings from just created DMA window
On sPAPR vfio_listener_region_add() is called in 2 situations:
1. a new listener is registered from vfio_connect_container();
2. a new IOMMU Memory Region is added from rtas_ibm_create_pe_dma_window().

In both cases vfio_listener_region_add() calls
memory_region_iommu_replay() to notify newly registered IOMMU notifiers
about existing mappings which is totally desirable for case 1.

However for case 2 it is nothing but noop as the window has just been
created and has no valid mappings so replaying those does not do anything.
It is barely noticeable with usual guests but if the window happens to be
really big, such no-op replay might take minutes and trigger RCU stall
warnings in the guest.

For example, a upcoming GPU RAM memory region mapped at 64TiB (right
after SPAPR_PCI_LIMIT) causes a 64bit DMA window to be at least 128TiB
which is (128<<40)/0x10000=2.147.483.648 TCEs to replay.

This mitigates the problem by adding an "skipping_replay" flag to
sPAPRTCETable and defining sPAPR own IOMMU MR replay() hook which does
exactly the same thing as the generic one except it returns early if
@skipping_replay==true.

Another way of fixing this would be delaying replay till the very first
H_PUT_TCE but this does not work if in-kernel H_PUT_TCE handler is
enabled (a likely case).

When "ibm,create-pe-dma-window" is complete, the guest will map only
required regions of the huge DMA window.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20190307050518.64968-2-aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 14:33:04 +11:00
David Gibson
e075623aa5 spapr: Force SPAPR_MEMORY_BLOCK_SIZE to be a hwaddr (64-bit)
SPAPR_MEMORY_BLOCK_SIZE is logically a difference in memory addresses, and
hence of type hwaddr which is 64-bit.  Previously it wasn't marked as such
which means that it could be treated as 32-bit.  That will work in some
circumstances but if multiplied by another 32-bit value it could lead to
a 32-bit overflow and an incorrect result.

One specific instance of this in spapr_lmb_dt_populate() was spotted by
Coverity (CID 1399145).

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 14:33:04 +11:00
Suraj Jitindar Singh
8ff43ee404 target/ppc/spapr: Add SPAPR_CAP_CCF_ASSIST
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>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
399b2896d4 target/ppc/spapr: Add workaround option to SPAPR_CAP_IBS
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>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
c982f5cf9a target/ppc/spapr: Add SPAPR_CAP_LARGE_DECREMENTER
Add spapr_cap SPAPR_CAP_LARGE_DECREMENTER to be used to control the
availability of the large decrementer for a guest.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301024317.22137-1-sjitindarsingh@gmail.com>
[dwg: Trivial style fix]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Greg Kurz
bb2bdd812e spapr: add hotplug hooks for PHB hotplug
Hotplugging PHBs is a machine-level operation, but PHBs reside on the
main system bus, so we register spapr machine as the handler for the
main system bus.

Provide the usual pre-plug, plug and unplug-request handlers.

Move the checking of the PHB index to the pre-plug handler. It is okay
to do that and assert in the realize function because the pre-plug
handler is always called, even for the oldest machine types we support.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
(Fixed interrupt controller phandle in "interrupt-map" and
 TCE table size in "ibm,dma-window" FDT fragment, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155059672926.1466090.13612804072190051439.stgit@bahia.lab.toulouse-stg.fr.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-26 09:21:25 +11:00
Michael Roth
962b6c3650 spapr: create DR connectors for PHBs
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155059670389.1466090.10015601248906623076.stgit@bahia.lab.toulouse-stg.fr.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-26 09:21:25 +11:00
Greg Kurz
345b12b99e spapr: Generate FDT fragment for CPUs at configure connector time
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155059666839.1466090.3833376527523126752.stgit@bahia.lab.toulouse-stg.fr.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-26 09:21:25 +11:00
Greg Kurz
62d38c9bd3 spapr: Generate FDT fragment for LMBs at configure connector time
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155059666331.1466090.6766540766297333313.stgit@bahia.lab.toulouse-stg.fr.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-26 09:21:25 +11:00
Benjamin Herrenschmidt
00fd075e18 target/ppc/spapr: Set LPCR:HR when using Radix mode
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>
2019-02-26 09:21:25 +11:00
Prasad J Pandit
27461d69a0 ppc: add host-serial and host-model machine attributes (CVE-2019-8934)
On ppc hosts, hypervisor shares following system attributes

  - /proc/device-tree/system-id
  - /proc/device-tree/model

with a guest. This could lead to information leakage and misuse.[*]
Add machine attributes to control such system information exposure
to a guest.

[*] https://wiki.openstack.org/wiki/OSSN/OSSN-0028

Reported-by: Daniel P. Berrangé <berrange@redhat.com>
Fix-suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-Id: <20190218181349.23885-1-ppandit@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-26 09:21:25 +11:00
Greg Kurz
56af66566d spapr/irq: Use the base ICP class for KVM
The base ICP class knows how to interact with KVM. Adapt sPAPR to use it
instead of the ICP KVM class.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155023080638.1011724.792095453419098948.stgit@bahia.lan>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-18 10:34:56 +11:00
Greg Kurz
5c7adcf422 spapr: Rename xics to intc in interrupt controller agnostic code
All this code is used with both the XICS and XIVE interrupt controllers.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-17 21:54:02 +11:00
Thomas Huth
0d8d6a24fc ppc: Fix duplicated typedefs to be able to compile with Clang in gnu99 mode
When compiling the ppc code with clang and -std=gnu99, there are a
couple of warnings/errors like this one:

  CC      ppc64-softmmu/hw/intc/xics.o
In file included from hw/intc/xics.c:35:
include/hw/ppc/xics.h:43:25: error: redefinition of typedef 'ICPState' is a C11 feature
      [-Werror,-Wtypedef-redefinition]
typedef struct ICPState ICPState;
                        ^
target/ppc/cpu.h:1181:25: note: previous definition is here
typedef struct ICPState ICPState;
                        ^
Work around the problems by including the proper headers in spapr.h
and by using struct forward declarations in cpu.h.

Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-01-22 05:14:33 +01:00
Cédric Le Goater
872ff3dea3 spapr: move the qemu_irq array under the machine
The qemu_irq array is now allocated at the machine level using a sPAPR
IRQ set_irq handler depending on the chosen interrupt mode. The use of
this handler is slightly inefficient today but it will become necessary
when the 'dual' interrupt mode is introduced.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-01-09 09:28:14 +11:00
Alexey Kardashevskiy
fea35ca4b8 ppc/spapr: Receive and store device tree blob from SLOF
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>
2019-01-09 09:28:13 +11:00
Laurent Vivier
c24ba3d0a3 spapr: Add H-Call H_HOME_NODE_ASSOCIATIVITY
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>
2019-01-09 09:28:13 +11:00
Cédric Le Goater
3ba3d0bc33 spapr: introduce an 'ic-mode' machine option
This option is used to select the interrupt controller mode (XICS or
XIVE) with which the machine will operate. XICS being the default
mode for now.

When running a machine with the XIVE interrupt mode backend, the guest
OS is required to have support for the XIVE exploitation mode. In the
case of legacy OS, the mode selected by CAS should be XICS and the OS
should fail to boot. However, QEMU could possibly detect it, terminate
the boot process and reset to stop in the SLOF firmware. This is not
yet handled.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:40:43 +11:00
Cédric Le Goater
db592b5b16 spapr: add an extra OV5 field to the sPAPR IRQ backend
The interrupt modes supported by the hypervisor are advertised to the
guest with new bits definitions of the option vector 5 of property
"ibm,arch-vec-5-platform-support. The byte 23 bits 0-1 of the OV5 are
defined as follow :

  0b00   PAPR 2.7 and earlier (Legacy systems)
  0b01   XIVE Exploitation mode only
  0b10   Either available

If the client/guest selects the XIVE interrupt mode, it informs the
hypervisor by returning the value 0b01 in byte 23 bits 0-1. A 0b00
value indicates the use of the XICS interrupt mode (Legacy systems).

The sPAPR IRQ backend is extended with these definitions and the
values are directly used to populate the "ibm,arch-vec-5-platform-support"
property. The interrupt mode is advertised under TCG and under KVM.
Although a KVM XIVE device is not yet available, the machine can still
operate with kernel_irqchip=off. However, we apply a restriction on
the CPU which is required to be a POWER9 when a XIVE interrupt
controller is in use.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:40:43 +11:00
Cédric Le Goater
23bcd5eb9a spapr: add hcalls support for the XIVE exploitation interrupt mode
The different XIVE virtualization structures (sources and event queues)
are configured with a set of Hypervisor calls :

 - H_INT_GET_SOURCE_INFO

   used to obtain the address of the MMIO page of the Event State
   Buffer (ESB) entry associated with the source.

 - H_INT_SET_SOURCE_CONFIG

   assigns a source to a "target".

 - H_INT_GET_SOURCE_CONFIG

   determines which "target" and "priority" is assigned to a source

 - H_INT_GET_QUEUE_INFO

   returns the address of the notification management page associated
   with the specified "target" and "priority".

 - H_INT_SET_QUEUE_CONFIG

   sets or resets the event queue for a given "target" and "priority".
   It is also used to set the notification configuration associated
   with the queue, only unconditional notification is supported for
   the moment. Reset is performed with a queue size of 0 and queueing
   is disabled in that case.

 - H_INT_GET_QUEUE_CONFIG

   returns the queue settings for a given "target" and "priority".

 - H_INT_RESET

   resets all of the guest's internal interrupt structures to their
   initial state, losing all configuration set via the hcalls
   H_INT_SET_SOURCE_CONFIG and H_INT_SET_QUEUE_CONFIG.

 - H_INT_SYNC

   issue a synchronisation on a source to make sure all notifications
   have reached their queue.

Calls that still need to be addressed :

   H_INT_SET_OS_REPORTING_LINE
   H_INT_GET_OS_REPORTING_LINE

See the code for more documentation on each hcall.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[dwg: Folded in fix for field accessors]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:37:38 +11:00
Cédric Le Goater
dcc345b61e spapr: introduce a new machine IRQ backend for XIVE
The XIVE IRQ backend uses the same layout as the new XICS backend but
covers the full range of the IRQ number space. The IRQ numbers for the
CPU IPIs are allocated at the bottom of this space, below 4K, to
preserve compatibility with XICS which does not use that range.

This should be enough given that the maximum number of CPUs is 1024
for the sPAPR machine under QEMU. For the record, the biggest POWER8
or POWER9 system has a maximum of 1536 HW threads (16 sockets, 192
cores, SMT8).

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:37:38 +11:00
Cédric Le Goater
1a518e7693 spapr: export and rename the xics_max_server_number() routine
The XIVE sPAPR IRQ backend will use it to define the number of ENDs of
the IC controller.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:29:10 +11:00
Suraj Jitindar Singh
b9a477b725 ppc/spapr_caps: Add SPAPR_CAP_NESTED_KVM_HV
Add the spapr cap SPAPR_CAP_NESTED_KVM_HV to be used to control the
availability of nested kvm-hv to the level 1 (L1) guest.

Assuming a hypervisor with support enabled an L1 guest can be allowed to
use the kvm-hv module (and thus run it's own kvm-hv guests) by setting:
-machine pseries,cap-nested-hv=true
or disabled with:
-machine pseries,cap-nested-hv=false

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-11-08 13:08:35 +11:00
Thomas Huth
0e947a89ce hw/ppc/spapr_rng: Introduce CONFIG_SPAPR_RNG switch for spapr_rng.c
The spapr-rng device is suboptimal when compared to virtio-rng, so
users might want to disable it in their builds. Thus let's introduce
a proper CONFIG switch to allow us to compile QEMU without this device.
The function spapr_rng_populate_dt is required for linking, so move it
to a different location.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-11-08 12:04:40 +11:00
Cédric Le Goater
ef01ed9d19 spapr: introduce a IRQ controller backend to the machine
This proposal moves all the related IRQ routines of the sPAPR machine
behind a sPAPR IRQ backend interface 'spapr_irq' to prepare for future
changes. First of which will be to increase the size of the IRQ number
space, then, will follow a new backend for the POWER9 XIVE IRQ controller.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-08-21 14:28:45 +10:00
Cédric Le Goater
82cffa2eb2 spapr: introduce a fixed IRQ number space
This proposal introduces a new IRQ number space layout using static
numbers for all devices, depending on a device index, and a bitmap
allocator for the MSI IRQ numbers which are negotiated by the guest at
runtime.

As the VIO device model does not have a device index but a "reg"
property, we introduce a formula to compute an IRQ number from a "reg"
value. It should minimize most of the collisions.

The previous layout is kept in pre-3.1 machines raising the
'legacy_irq_allocation' machine class flag.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-08-21 14:28:45 +10:00
Philippe Mathieu-Daudé
ab3dd74924 hw/ppc: Use the IEC binary prefix definitions
It eases code review, unit is explicit.

Patch generated using:

  $ git grep -E '(1024|2048|4096|8192|(<<|>>).?(10|20|30))' hw/ include/hw/

and modified manually.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20180625124238.25339-33-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-07-02 15:41:16 +02:00
David Gibson
123eec6552 spapr: Use maximum page size capability to simplify memory backend checking
The way we used to handle KVM allowable guest pagesizes for PAPR guests
required some convoluted checking of memory attached to the guest.

The allowable pagesizes advertised to the guest cpus depended on the memory
which was attached at boot, but then we needed to ensure that any memory
later hotplugged didn't change which pagesizes were allowed.

Now that we have an explicit machine option to control the allowable
maximum pagesize we can simplify this.  We just check all memory backends
against that declared pagesize.  We check base and cold-plugged memory at
reset time, and hotplugged memory at pre_plug() time.

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>
2018-06-22 14:19:07 +10:00
David Gibson
2309832afd spapr: Maximum (HPT) pagesize property
The way the POWER Hash Page Table (HPT) MMU is virtualized by KVM HV means
that every page that the guest puts in the pagetables must be truly
physically contiguous, not just GPA-contiguous.  In effect this means that
an HPT guest can't use any pagesizes greater than the host page size used
to back its memory.

At present we handle this by changing what we advertise to the guest based
on the backing pagesizes.  This is pretty bad, because it means the guest
sees a different environment depending on what should be host configuration
details.

As a start on fixing this, we add a new capability parameter to the
pseries machine type which gives the maximum allowed pagesizes for an
HPT guest.  For now we just create and validate the parameter without
making it do anything.

For backwards compatibility, on older machine types we set it to the max
available page size for the host.  For the 3.0 machine type, we fix it to
16, the intention being to only allow HPT pagesizes up to 64kiB by default
in future.

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>
2018-06-22 14:19:07 +10:00
Cédric Le Goater
71b5c8d26e spapr: remove unused spapr_irq routines
spapr_irq_alloc_block and spapr_irq_alloc() are now deprecated.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-06-21 21:22:53 +10:00
Cédric Le Goater
4fe75a8ccd spapr: split the IRQ allocation sequence
Today, when a device requests for IRQ number in a sPAPR machine, the
spapr_irq_alloc() routine first scans the ICSState status array to
find an empty slot and then performs the assignement of the selected
numbers. Split this sequence in two distinct routines : spapr_irq_find()
for lookups and spapr_irq_claim() for claiming the IRQ numbers.

This will ease the introduction of a static layout of IRQ numbers.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-06-21 21:22:53 +10:00
David Gibson
e2e4f64118 spapr: Add cpu_apply hook to capabilities
spapr capabilities have an apply hook to actually activate (or deactivate)
the feature in the system at reset time.  However, a number of capabilities
affect the setup of cpus, and need to be applied to each of them -
including hotplugged cpus for extra complication.  To make this simpler,
add an optional cpu_apply hook that is called from spapr_cpu_reset().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2018-06-21 21:22:53 +10:00
David Gibson
9f6edd066e spapr: Compute effective capability values earlier
Previously, the effective values of the various spapr capability flags
were only determined at machine reset time.  That was a lazy way of making
sure it was after cpu initialization so it could use the cpu object to
inform the defaults.

But we've now improved the compat checking code so that we don't need to
instantiate the cpus to use it.  That lets us move the resolution of the
capability defaults much earlier.

This is going to be necessary for some future capabilities.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2018-06-21 21:22:53 +10:00
David Hildenbrand
0c9269a52d spapr: rename "hotplug memory" terminology to "device memory"
Let's make it clear at relevant places that we are dealing with device
memory. That it can be used for memory hotplug is just a special case.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-11-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
[ehabkost: rebased series, solved conflicts at spapr.c]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-05-07 10:00:02 -03:00
David Hildenbrand
b0c14ec4ef machine: make MemoryHotplugState accessible via the machine
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>
2018-05-07 10:00:02 -03:00
Suraj Jitindar Singh
c76c0d3090 ppc/spapr-caps: Convert cap-ibs to custom spapr-cap
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>
2018-03-06 13:16:29 +11:00
Greg Kurz
14bb4486c8 spapr: rename spapr_vcpu_id() to spapr_get_vcpu_id()
The spapr_vcpu_id() function is an accessor actually. Let's rename it
for symmetry with the recently added spapr_set_vcpu_id() helper.

The motivation behind this is that a later patch will consolidate
the VCPU id formula in a function and spapr_vcpu_id looks like an
appropriate name.

Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-02-16 12:14:26 +11:00
Greg Kurz
648edb6475 spapr: move VCPU calculation to core machine code
The VCPU ids are currently computed and assigned to each individual
CPU threads in spapr_cpu_core_realize(). But the numbering logic
of VCPU ids is actually a machine-level concept, and many places
in hw/ppc/spapr.c also have to compute VCPU ids out of CPU indexes.

The current formula used in spapr_cpu_core_realize() is:

    vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i

where:

    cc->core_id is a multiple of smp_threads
    cpu_index = cc->core_id + i
    0 <= i < smp_threads

So we have:

    cpu_index % smp_threads == i
    cc->core_id / smp_threads == cpu_index / smp_threads

hence:

    vcpu_id =
        (cpu_index / smp_threads) * spapr->vsmt + cpu_index % smp_threads;

This formula was used before VSMT at the time VCPU ids where computed
at the target emulation level. It has the advantage of being useable
to derive a VPCU id out of a CPU index only. It is fitted for all the
places where the machine code has to compute a VCPU id.

This patch introduces an accessor to set the VCPU id in a PowerPCCPU object
using the above formula. It is a first step to consolidate all the VCPU id
logic in a single place.

Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-02-16 12:14:26 +11:00
Suraj Jitindar Singh
c59704b254 target/ppc/spapr: Add H-Call H_GET_CPU_CHARACTERISTICS
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>
2018-01-29 14:24:55 +11:00
Suraj Jitindar Singh
4be8d4e7d9 target/ppc/spapr_caps: Add new tristate cap safe_indirect_branch
Add new tristate cap cap-ibs to represent the indirect branch
serialisation capability.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-29 14:24:55 +11:00
Suraj Jitindar Singh
09114fd817 target/ppc/spapr_caps: Add new tristate cap safe_bounds_check
Add new tristate cap cap-sbbc to represent the speculation barrier
bounds checking capability.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-29 14:24:55 +11:00
Suraj Jitindar Singh
8f38eaf8f9 target/ppc/spapr_caps: Add new tristate cap safe_cache
Add new tristate cap cap-cfpc to represent the cache flush on privilege
change capability.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-29 14:24:55 +11:00
Suraj Jitindar Singh
6898aed77f target/ppc/spapr_caps: Add support for tristate spapr_capabilities
spapr_caps are used to represent the level of support for various
capabilities related to the spapr machine type. Currently there is
only support for boolean capabilities.

Add support for tristate capabilities by implementing their get/set
functions. These capabilities can have the values 0, 1 or 2
corresponding to broken, workaround and fixed.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-29 14:24:55 +11:00
Suraj Jitindar Singh
8acc2ae5e9 target/ppc/kvm: Add cap_ppc_safe_[cache/bounds_check/indirect_branch]
Add three new kvm capabilities used to represent the level of host support
for three corresponding workarounds.

Host support for each of the capabilities is queried through the
new ioctl KVM_PPC_GET_CPU_CHAR which returns four uint64 quantities. The
first two, character and behaviour, represent the available
characteristics of the cpu and the behaviour of the cpu respectively.
The second two, c_mask and b_mask, represent the mask of known bits for
the character and beheviour dwords respectively.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[dwg: Correct some compile errors due to name change in final kernel
 patch version]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-29 14:24:55 +11:00
Suraj Jitindar Singh
4e5fe3688e hw/ppc/spapr_caps: Rework spapr_caps to use uint8 internal representation
Currently spapr_caps are tied to boolean values (on or off). This patch
reworks the caps so that they can have any uint8 value. This allows more
capabilities with various values to be represented in the same way
internally. Capabilities are numbered in ascending order. The internal
representation of capability values is an array of uint8s in the
sPAPRMachineState, indexed by capability number.

Capabilities can have their own name, description, options, getter and
setter functions, type and allow functions. They also each have their own
section in the migration stream. Capabilities are only migrated if they
were explictly set on the command line, with the assumption that
otherwise the default will match.

On migration we ensure that the capability value on the destination
is greater than or equal to the capability value from the source. So
long at this remains the case then the migration is considered
compatible and allowed to continue.

This patch implements generic getter and setter functions for boolean
capabilities. It also converts the existings cap-htm, cap-vsx and
cap-dfp capabilities to this new format.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-17 09:35:24 +11:00
David Gibson
2d1fb9bc8e spapr: Handle Decimal Floating Point (DFP) as an optional capability
Decimal Floating Point has been available on POWER7 and later (server)
cpus.  However, it can be disabled on the hypervisor, meaning that it's
not available to guests.

We currently handle this by conditionally advertising DFP support in the
device tree depending on whether the guest CPU model supports it - which
can also depend on what's allowed in the host for -cpu host.  That can lead
to confusion on migration, since host properties are silently affecting
guest visible properties.

This patch handles it by treating it as an optional capability for the
pseries machine type.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-01-17 09:35:24 +11:00
David Gibson
2938664286 spapr: Handle VMX/VSX presence as an spapr capability flag
We currently have some conditionals in the spapr device tree code to decide
whether or not to advertise the availability of the VMX (aka Altivec) and
VSX vector extensions to the guest, based on whether the guest cpu has
those features.

This can lead to confusion and subtle failures on migration, since it makes
a guest visible change based only on host capabilities.  We now have a
better mechanism for this, in spapr capabilities flags, which explicitly
depend on user options rather than host capabilities.

Rework the advertisement of VSX and VMX based on a new VSX capability.  We
no longer bother with a conditional for VMX support, because every CPU
that's ever been supported by the pseries machine type supports VMX.

NOTE: Some userspace distributions (e.g. RHEL7.4) already rely on
availability of VSX in libc, so using cap-vsx=off may lead to a fatal
SIGILL in init.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-01-17 09:35:24 +11:00
David Gibson
be85537d65 spapr: Validate capabilities on migration
Now that the "pseries" machine type implements optional capabilities (well,
one so far) there's the possibility of having different capabilities
available at either end of a migration.  Although arguably a user error,
it would be nice to catch this situation and fail as gracefully as we can.

This adds code to migrate the capabilities flags.  These aren't pulled
directly into the destination's configuration since what the user has
specified on the destination command line should take precedence.  However,
they are checked against the destination capabilities.

If the source was using a capability which is absent on the destination,
we fail the migration, since that could easily cause a guest crash or other
bad behaviour.  If the source lacked a capability which is present on the
destination we warn, but allow the migration to proceed.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-01-17 09:35:24 +11:00
David Gibson
ee76a09fc7 spapr: Treat Hardware Transactional Memory (HTM) as an optional capability
This adds an spapr capability bit for Hardware Transactional Memory.  It is
enabled by default for pseries-2.11 and earlier machine types. with POWER8
or later CPUs (as it must be, since earlier qemu versions would implicitly
allow it).  However it is disabled by default for the latest pseries-2.12
machine type.

This means that with the latest machine type, HTM will not be available,
regardless of CPU, unless it is explicitly enabled on the command line.
That change is made on the basis that:

 * This way running with -M pseries,accel=tcg will start with whatever cpu
   and will provide the same guest visible model as with accel=kvm.
     - More specifically, this means existing make check tests don't have
       to be modified to use cap-htm=off in order to run with TCG

 * We hope to add a new "HTM without suspend" feature in the not too
   distant future which could work on both POWER8 and POWER9 cpus, and
   could be enabled by default.

 * Best guesses suggest that future POWER cpus may well only support the
   HTM-without-suspend model, not the (frankly, horribly overcomplicated)
   POWER8 style HTM with suspend.

 * Anecdotal evidence suggests problems with HTM being enabled when it
   wasn't wanted are more common than being missing when it was.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-01-17 09:35:24 +11:00
David Gibson
33face6b89 spapr: Capabilities infrastructure
Because PAPR is a paravirtual environment access to certain CPU (or other)
facilities can be blocked by the hypervisor.  PAPR provides ways to
advertise in the device tree whether or not those features are available to
the guest.

In some places we automatically determine whether to make a feature
available based on whether our host can support it, in most cases this is
based on limitations in the available KVM implementation.

Although we correctly advertise this to the guest, it means that host
factors might make changes to the guest visible environment which is bad:
as well as generaly reducing reproducibility, it means that a migration
between different host environments can easily go bad.

We've mostly gotten away with it because the environments considered mature
enough to be well supported (basically, KVM on POWER8) have had consistent
feature availability.  But, it's still not right and some limitations on
POWER9 is going to make it more of an issue in future.

This introduces an infrastructure for defining "sPAPR capabilities".  These
are set by default based on the machine version, masked by the capabilities
of the chosen cpu, but can be overriden with machine properties.

The intention is at reset time we verify that the requested capabilities
can be supported on the host (considering TCG, KVM and/or host cpu
limitations).  If not we simply fail, rather than silently modifying the
advertised featureset to the guest.

This does mean that certain configurations that "worked" may now fail, but
such configurations were already more subtly broken.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-01-17 09:35:24 +11:00
Greg Kurz
bb2d8ab636 spapr: fix LSI interrupt specifiers in the device tree
LoPAPR 1.1 B.6.9.1.2 describes the "#interrupt-cells" property of the
PowerPC External Interrupt Source Controller node as follows:

“#interrupt-cells”

  Standard property name to define the number of cells in an interrupt-
  specifier within an interrupt domain.

  prop-encoded-array: An integer, encoded as with encode-int, that denotes
  the number of cells required to represent an interrupt specifier in its
  child nodes.

  The value of this property for the PowerPC External Interrupt option shall
  be 2. Thus all interrupt specifiers (as used in the standard “interrupts”
  property) shall consist of two cells, each containing an integer encoded
  as with encode-int. The first integer represents the interrupt number the
  second integer is the trigger code: 0 for edge triggered, 1 for level
  triggered.

This patch fixes the interrupt specifiers in the "interrupt-map" property
of the PHB node, that were setting the second cell to 8 (confusion with
IRQ_TYPE_LEVEL_LOW ?) instead of 1.

VIO devices and RTAS event sources use the same format for interrupt
specifiers: while here, we introduce a common helper to handle the
encoding details.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
--
v3: - reference public LoPAPR instead of internal PAPR+ in changelog
    - change helper name to spapr_dt_xics_irq()

v2: - drop the erroneous changes to the "interrupts" prop in PCI device nodes
    - introduce a common helper to encode interrupt specifiers
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-12-15 09:49:24 +11:00
Cédric Le Goater
7718375584 spapr: introduce a spapr_qirq() helper
xics_get_qirq() is only used by the sPAPR machine. Let's move it there
and change its name to reflect its scope. It will be useful for XIVE
support which will use its own set of qirqs.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-12-15 09:49:24 +11:00
Cédric Le Goater
60c6823b9b spapr: move the IRQ allocation routines under the machine
Also change the prototype to use a sPAPRMachineState and prefix them
with spapr_irq_. It will let us synchronise the IRQ allocation with
the XIVE interrupt mode when available.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-12-15 09:49:24 +11:00
Igor Mammedov
2e9c10eba0 ppc: spapr: use generic cpu_model parsing
use generic cpu_model parsing introduced by
 (6063d4c0f vl.c: convert cpu_model to cpu type and set of global properties before machine_init())

it allows to:
  * replace sPAPRMachineClass::tcg_default_cpu with
    MachineClass::default_cpu_type
  * drop cpu_parse_cpu_model() from hw/ppc/spapr.c and reuse
    one in vl.c
  * simplify spapr_get_cpu_core_type() by removing
    not needed anymore recurrsion since alias look up
    happens earlier at vl.c and spapr_get_cpu_core_type()
    works only with resulted from that cpu type.
  * spapr no more needs to parse/depend on being phased out
    MachineState::cpu_model, all tha parsing done by generic
    code and target specific callback.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
[dwg: Correct minor compile error]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-10-17 10:34:01 +11:00
Igor Mammedov
b8e999673b ppc: move '-cpu foo,compat=xxx' parsing into ppc_cpu_parse_featurestr()
there is a dedicated callback CPUClass::parse_features
which purpose is to convert -cpu features into a set of
global properties AND deal with compat/legacy features
that couldn't be directly translated into CPU's properties.

Create ppc variant of it (ppc_cpu_parse_featurestr) and
move 'compat=val' handling from spapr_cpu_core.c into it.
That removes a dependency of board/core code on cpu_model
parsing and would let to reuse common -cpu parsing
introduced by 6063d4c0

Set "max-cpu-compat" property only if it exists, in practice
it should limit 'compat' hack to spapr machine and allow
to avoid including machine/spapr headers in target/ppc/cpu.c

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-10-17 10:34:00 +11:00
Sam Bobroff
fa98fbfcdf PPC: KVM: Support machine option to set VSMT mode
KVM now allows writing to KVM_CAP_PPC_SMT which has previously been
read only. Doing so causes KVM to act, for that VM, as if the host's
SMT mode was the given value. This is particularly important on Power
9 systems because their default value is 1, but they are able to
support values up to 8.

This patch introduces a way to control this capability via a new
machine property called VSMT ("Virtual SMT"). If the value is not set
on the command line a default is chosen that is, when possible,
compatible with legacy systems.

Note that the intialization of KVM_CAP_PPC_SMT has changed slightly
because it has changed (in KVM) from a global capability to a
VM-specific one. This won't cause a problem on older KVMs because VM
capabilities fall back to global ones.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-09-08 09:30:55 +10:00
Sam Bobroff
2e886fb391 ppc: spapr: Make VCPU ID handling private to SPAPR
The concept of a VCPU ID that differs from the CPU's index
(cpu->cpu_index) exists only within SPAPR machines so, move the
functions ppc_get_vcpu_id() and ppc_get_cpu_by_vcpu_id() into spapr.c
and rename them appropriately.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-09-08 09:30:55 +10:00
Daniel Henrique Barboza
5625817423 hw/ppc: clear pending_events on machine reset
The sPAPR machine isn't clearing up the pending events QTAILQ on
machine reboot. This allows for unprocessed hotplug/epow events
to persist in the queue after reset and, when reasserting the IRQs in
check_exception later on, these will be being processed by the OS.

This patch implements a new function called 'spapr_clear_pending_events'
that clears up the pending_events QTAILQ. This helper is then called
inside ppc_spapr_reset to clear up the events queue, preventing
old/deprecated events from persisting after a reset.

Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-09-08 09:30:54 +10:00
David Gibson
2772cf6be9 pseries: Use smaller default hash page tables when guest can resize
We've now implemented a PAPR extension allowing PAPR guest to resize
their hash page table (HPT) during runtime.

This patch makes use of that facility to allocate smaller HPTs by default.
Specifically when a guest is aware of the HPT resize facility, qemu sizes
the HPT to the initial memory size, rather than the maximum memory size on
the assumption that the guest will resize its HPT if necessary for hot
plugged memory.

When the initial memory size is much smaller than the maximum memory size
(a common configuration with e.g. oVirt / RHEV) then this can save
significant memory on the HPT.

If the guest does *not* advertise HPT resize awareness when it makes the
ibm,client-architecture-support call, qemu resizes the HPT for maxmimum
memory size (unless it's been configured not to allow such guests at all).

For now we make that reallocation assuming the guest has not yet used the
HPT at all.  That's true in practice, but not, strictly, an architectural
or PAPR requirement.  If we need to in future we can fix this by having
the client-architecture-support call reboot the guest with the revised
HPT size (the client-architecture-support call is explicitly permitted to
trigger a reboot in this way).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
2017-07-17 15:07:05 +10:00
David Gibson
0b0b831016 pseries: Implement HPT resizing
This patch implements hypercalls allowing a PAPR guest to resize its own
hash page table.  This will eventually allow for more flexible memory
hotplug.

The implementation is partially asynchronous, handled in a special thread
running the hpt_prepare_thread() function.  The state of a pending resize
is stored in SPAPR_MACHINE->pending_hpt.

The H_RESIZE_HPT_PREPARE hypercall will kick off creation of a new HPT, or,
if one is already in progress, monitor it for completion.  If there is an
existing HPT resize in progress that doesn't match the size specified in
the call, it will cancel it, replacing it with a new one matching the
given size.

The H_RESIZE_HPT_COMMIT completes transition to a resized HPT, and can only
be called successfully once H_RESIZE_HPT_PREPARE has successfully
completed initialization of a new HPT.  The guest must ensure that there
are no concurrent accesses to the existing HPT while this is called (this
effectively means stop_machine() for Linux guests).

For now H_RESIZE_HPT_COMMIT goes through the whole old HPT, rehashing each
HPTE into the new HPT.  This can have quite high latency, but it seems to
be of the order of typical migration downtime latencies for HPTs of size
up to ~2GiB (which would be used in a 256GiB guest).

In future we probably want to move more of the rehashing to the "prepare"
phase, by having H_ENTER and other hcalls update both current and
pending HPTs.  That's a project for another day, but should be possible
without any changes to the guest interface.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-07-17 15:07:05 +10:00
David Gibson
30f4b05bd0 pseries: Stubs for HPT resizing
This introduces stub implementations of the H_RESIZE_HPT_PREPARE and
H_RESIZE_HPT_COMMIT hypercalls which we hope to add in a PAPR
extension to allow run time resizing of a guest's hash page table.  It
also adds a new machine property for controlling whether this new
facility is available.

For now we only allow resizing with TCG, allowing it with KVM will require
kernel changes as well.

Finally, it adds a new string to the hypertas property in the device
tree, advertising to the guest the availability of the HPT resizing
hypercalls.  This is a tentative suggested value, and would need to be
standardized by PAPR before being merged.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
2017-07-17 15:07:05 +10:00
David Gibson
5341258e86 spapr: Minor cleanups to events handling
The rtas_error_log structure is marked packed, which strongly suggests its
precise layout is important to match an external interface.  Along with
that one could expect it to have a fixed endianness to match the same
interface.  That used to be the case - matching the layout of PAPR RTAS
event format and requiring BE fields.

Now, however, it's only used embedded within sPAPREventLogEntry with the
fields in native order, since they're processed internally.

Clear that up by removing the nested structure in sPAPREventLogEntry.
struct rtas_error_log is moved back to spapr_events.c where it is used as
a temporary to help convert the fields in sPAPREventLogEntry to the correct
in memory format when delivering an event to the guest.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-07-17 15:07:05 +10:00
Daniel Henrique Barboza
fd38804b38 spapr: migrate pending_events of spapr state
In racing situations between hotplug events and migration operation,
a rtas hotplug event could have not yet be delivered to the source
guest when migration is started. In this case the pending_events of
spapr state need be transmitted to the target so that the hotplug
event can be finished on the target.

To achieve the minimal VMSD possible to migrate the pending_events list,
this patch makes the changes in spapr_events.c:

- 'log_type' of sPAPREventLogEntry struct deleted. This information can be
derived by inspecting the rtas_error_log summary field. A new function
called 'spapr_event_log_entry_type' was added to retrieve the type of
a given sPAPREventLogEntry.

- sPAPREventLogEntry, epow_log_full and hp_log_full were redesigned. The
only data we're going to migrate in the VMSD is the event log data itself,
which can be divided in two parts: a rtas_error_log header and an extended
event log field. The rtas_error_log header contains information about the
size of the extended log field, which can be used inside VMSD as the size
parameter of the VBUFFER_ALOC field that will store it. To allow this use,
the header.extended_length field must be exposed inline to the VMSD instead
of embedded into a 'data' field that holds everything. With this in mind,
the following changes were done:

    * a new 'header' field was added to sPAPREventLogEntry. This field holds a
a struct rtas_error_log inline.
    * the declaration of the 'rtas_error_log' struct was moved to spapr.h
to be visible to the VMSD macros.
    * 'data' field of sPAPREventLogEntry was renamed to 'extended_log' and
now holds only the contents of the extended event log.
   *  'struct rtas_error_log hdr' were taken away from both epow_log_full
and hp_log_full. This information is now available at the header field of
sPAPREventLogEntry.
   * epow_log_full and hp_log_full were renamed to epow_extended_log and
hp_extended_log respectively. This rename makes it clearer to understand
the new purpose of both structures: hold the information of an extended
event log field.
    * spapr_powerdown_req and spapr_hotplug_req_event now creates a
sPAPREventLogEntry structure that contains the full rtas log entry.
    * rtas_event_log_queue and rtas_event_log_dequeue now receives a
sPAPREventLogEntry pointer as a parameter instead of a void pointer.

- the endianess of the sPAPREventLogEntry header is now native instead
of be32. We can use the fields in native endianess internally and write
them in be32 in the guest physical memory inside 'check_exception'. This
allows the VMSD inside spapr.c to read the correct size of the
entended_log field.

- inside spapr.c, pending_events is put in a subsection in the spapr state
VMSD to make sure migration across different versions is not broken.

A small change in rtas_event_log_queue and rtas_event_log_dequeue were also
made: instead of calling qdev_get_machine(), both functions now receive
a pointer to the sPAPRMachineState. This pointer is already available in
the callers of these functions and we don't need to waste resources
calling qdev() again.

Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-07-17 15:07:05 +10:00
Alexey Kardashevskiy
1221a47467 memory/iommu: introduce IOMMUMemoryRegionClass
This finishes QOM'fication of IOMMUMemoryRegion by introducing
a IOMMUMemoryRegionClass. This also provides a fastpath analog for
IOMMU_MEMORY_REGION_GET_CLASS().

This makes IOMMUMemoryRegion an abstract class.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170711035620.4232-3-aik@ozlabs.ru>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:41 +02:00
Alexey Kardashevskiy
3df9d74806 memory/iommu: QOM'fy IOMMU MemoryRegion
This defines new QOM object - IOMMUMemoryRegion - with MemoryRegion
as a parent.

This moves IOMMU-related fields from MR to IOMMU MR. However to avoid
dymanic QOM casting in fast path (address_space_translate, etc),
this adds an @is_iommu boolean flag to MR and provides new helper to
do simple cast to IOMMU MR - memory_region_get_iommu. The flag
is set in the instance init callback. This defines
memory_region_is_iommu as memory_region_get_iommu()!=NULL.

This switches MemoryRegion to IOMMUMemoryRegion in most places except
the ones where MemoryRegion may be an alias.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20170711035620.4232-2-aik@ozlabs.ru>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:41 +02:00
Greg Kurz
498cd99544 spapr: refresh "platform-specific" hcalls comment
We have more of these since the addition of KVMPPC_H_LOGICAL_MEMOP in 2012.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-07-11 11:04:01 +10:00
Greg Kurz
04d0ffbd52 spapr: make spapr_populate_hotplug_cpu_dt() static
Since commit ff9006ddbf ("spapr: move spapr_core_[foo]plug() callbacks
close to machine code in spapr.c"), this function doesn't need to be extern
anymore.

Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-07-11 11:04:01 +10:00
Greg Kurz
46f7afa370 spapr: fix migration of ICPState objects from/to older QEMU
Commit 5bc8d26de2 ("spapr: allocate the ICPState object from under
sPAPRCPUCore") moved ICPState objects from the machine to CPU cores.
This is an improvement since we no longer allocate ICPState objects
that will never be used. But it has the side-effect of breaking
migration of older machine types from older QEMU versions.

This patch allows spapr to register dummy "icp/server" entries to vmstate.
These entries use a dedicated VMStateDescription that can swallow and
discard state of an incoming migration stream, and that don't send anything
on outgoing migration.

As for real ICPState objects, the instance_id is the cpu_index of the
corresponding vCPU, which happens to be equal to the generated instance_id
of older machine types.

The machine can unregister/register these entries when CPUs are dynamically
plugged/unplugged.

This is only available for pseries-2.9 and older machines, thanks to a
compat property.

Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-06-30 14:03:31 +10:00
David Gibson
7843c0d60d pseries: Move CPU compatibility property to machine
Server class POWER CPUs have a "compat" property, which is used to set the
backwards compatibility mode for the processor.  However, this only makes
sense for machine types which don't give the guest access to hypervisor
privilege - otherwise the compatibility level is under the guest's control.

To reflect this, this removes the CPU 'compat' property and instead
creates a 'max-cpu-compat' property on the pseries machine.  Strictly
speaking this breaks compatibility, but AFAIK the 'compat' option was
never (directly) used with -device or device_add.

The option was used with -cpu.  So, to maintain compatibility, this
patch adds a hack to the cpu option parsing to strip out any compat
options supplied with -cpu and set them on the machine property
instead of the now deprecated cpu property.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Tested-by: Andrea Bolognani <abologna@redhat.com>
2017-06-30 14:03:31 +10:00