Commit Graph

1277 Commits

Author SHA1 Message Date
Michael Ellerman
62623d5f91 KVM: PPC: Book3S HV: Fix build error when SMP=n
Commit 5d375199ea ("KVM: PPC: Book3S HV: Set server for passed-through
interrupts") broke the SMP=n build:

  arch/powerpc/kvm/book3s_hv_rm_xics.c:758:2: error: implicit declaration of function 'get_hard_smp_processor_id'

That is because we lost the implicit include of asm/smp.h, so include it
explicitly to get the definition for get_hard_smp_processor_id().

Fixes: 5d375199ea ("KVM: PPC: Book3S HV: Set server for passed-through interrupts")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-22 08:44:37 +11:00
Thomas Huth
fa73c3b25b KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register
The MMCR2 register is available twice, one time with number 785
(privileged access), and one time with number 769 (unprivileged,
but it can be disabled completely). In former times, the Linux
kernel was using the unprivileged register 769 only, but since
commit 8dd75ccb57 ("powerpc: Use privileged SPR number
for MMCR2"), it uses the privileged register 785 instead.
The KVM-PR code then of course also switched to use the SPR 785,
but this is causing older guest kernels to crash, since these
kernels still access 769 instead. So to support older kernels
with KVM-PR again, we have to support register 769 in KVM-PR, too.

Fixes: 8dd75ccb57
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-27 15:14:29 +10:00
Thomas Huth
2365f6b67c KVM: PPC: Book3S PR: Support 64kB page size on POWER8E and POWER8NVL
On POWER8E and POWER8NVL, KVM-PR does not announce support for
64kB page sizes and 1TB segments yet. Looks like this has just
been forgotton so far, since there is no reason why this should
be different to the normal POWER8 CPUs.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-27 15:14:29 +10:00
Dan Carpenter
ac0e89bb47 KVM: PPC: BookE: Fix a sanity check
We use logical negate where bitwise negate was intended.  It means that
we never return -EINVAL here.

Fixes: ce11e48b7f ('KVM: PPC: E500: Add userspace debug stub support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-27 15:14:29 +10:00
Paul Mackerras
b009031f74 KVM: PPC: Book3S HV: Take out virtual core piggybacking code
This takes out the code that arranges to run two (or more) virtual
cores on a single subcore when possible, that is, when both vcores
are from the same VM, the VM is configured with one CPU thread per
virtual core, and all the per-subcore registers have the same value
in each vcore.  Since the VTB (virtual timebase) is a per-subcore
register, and will almost always differ between vcores, this code
is disabled on POWER8 machines, meaning that it is only usable on
POWER7 machines (which don't have VTB).  Given the tiny number of
POWER7 machines which have firmware that allows them to run HV KVM,
the benefit of simplifying the code outweighs the loss of this
feature on POWER7 machines.

Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-27 14:42:07 +10:00
Paul Mackerras
88b02cf97b KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
POWER8 has one virtual timebase (VTB) register per subcore, not one
per CPU thread.  The HV KVM code currently treats VTB as a per-thread
register, which can lead to spurious soft lockup messages from guests
which use the VTB as the time source for the soft lockup detector.
(CPUs before POWER8 did not have the VTB register.)

For HV KVM, this fixes the problem by making only the primary thread
in each virtual core save and restore the VTB value.  With this,
the VTB state becomes part of the kvmppc_vcore structure.  This
also means that "piggybacking" of multiple virtual cores onto one
subcore is not possible on POWER8, because then the virtual cores
would share a single VTB register.

PR KVM emulates a VTB register, which is per-vcpu because PR KVM
has no notion of CPU threads or SMT.  For PR KVM we move the VTB
state into the kvmppc_vcpu_book3s struct.

Cc: stable@vger.kernel.org # v3.14+
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-27 14:41:39 +10:00
Luiz Capitulino
235539b48a kvm: add stubs for arch specific debugfs support
Two stubs are added:

 o kvm_arch_has_vcpu_debugfs(): must return true if the arch
   supports creating debugfs entries in the vcpu debugfs dir
   (which will be implemented by the next commit)

 o kvm_arch_create_vcpu_debugfs(): code that creates debugfs
   entries in the vcpu debugfs dir

For x86, this commit introduces a new file to avoid growing
arch/x86/kvm/x86.c even more.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-16 16:57:47 +02:00
Markus Elfring
aad9e5ba24 KVM: PPC: e500: Rename jump labels in kvmppc_e500_tlb_init()
Adjust jump labels according to the current Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-13 14:32:47 +10:00
Markus Elfring
90235dc19e KVM: PPC: e500: Use kmalloc_array() in kvmppc_e500_tlb_init()
* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kmalloc_array".

* Replace the specification of a data structure by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:13:01 +10:00
Markus Elfring
b0ac477bc4 KVM: PPC: e500: Replace kzalloc() calls by kcalloc() in two functions
* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kcalloc".

  Suggested-by: Paolo Bonzini <pbonzini@redhat.com>

  This issue was detected also by using the Coccinelle software.

* Replace the specification of data structures by pointer dereferences
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:56 +10:00
Markus Elfring
cfb60813fb KVM: PPC: e500: Delete an unnecessary initialisation in kvm_vcpu_ioctl_config_tlb()
The local variable "g2h_bitmap" will be set to an appropriate value
a bit later. Thus omit the explicit initialisation at the beginning.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:51 +10:00
Markus Elfring
46d4e74792 KVM: PPC: e500: Less function calls in kvm_vcpu_ioctl_config_tlb() after error detection
The kfree() function was called in two cases by the
kvm_vcpu_ioctl_config_tlb() function during error handling
even if the passed data structure element contained a null pointer.

* Split a condition check for memory allocation failures.

* Adjust jump targets according to the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:46 +10:00
Markus Elfring
f3c0ce86a8 KVM: PPC: e500: Use kmalloc_array() in kvm_vcpu_ioctl_config_tlb()
* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kmalloc_array".

  This issue was detected by using the Coccinelle software.

* Replace the specification of a data type by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:40 +10:00
Suresh Warrier
65e7026a6c KVM: PPC: Book3S HV: Counters for passthrough IRQ stats
Add VCPU stat counters to track affinity for passthrough
interrupts.

pthru_all: Counts all passthrough interrupts whose IRQ mappings are
           in the kvmppc_passthru_irq_map structure.
pthru_host: Counts all cached passthrough interrupts that were injected
	    from the host through kvm_set_irq (i.e. not handled in
	    real mode).
pthru_bad_aff: Counts how many cached passthrough interrupts have
               bad affinity (receiving CPU is not running VCPU that is
	       the target of the virtual interrupt in the guest).

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:34 +10:00
Paul Mackerras
5d375199ea KVM: PPC: Book3S HV: Set server for passed-through interrupts
When a guest has a PCI pass-through device with an interrupt, it
will direct the interrupt to a particular guest VCPU.  In fact the
physical interrupt might arrive on any CPU, and then get
delivered to the target VCPU in the emulated XICS (guest interrupt
controller), and eventually delivered to the target VCPU.

Now that we have code to handle device interrupts in real mode
without exiting to the host kernel, there is an advantage to having
the device interrupt arrive on the same sub(core) as the target
VCPU is running on.  In this situation, the interrupt can be
delivered to the target VCPU without any exit to the host kernel
(using a hypervisor doorbell interrupt between threads if
necessary).

This patch aims to get passed-through device interrupts arriving
on the correct core by setting the interrupt server in the real
hardware XICS for the interrupt to the first thread in the (sub)core
where its target VCPU is running.  We do this in the real-mode H_EOI
code because the H_EOI handler already needs to look at the
emulated ICS state for the interrupt (whereas the H_XIRR handler
doesn't), and we know we are running in the target VCPU context
at that point.

We set the server CPU in hardware using an OPAL call, regardless of
what the IRQ affinity mask for the interrupt says, and without
updating the affinity mask.  This amounts to saying that when an
interrupt is passed through to a guest, as a matter of policy we
allow the guest's affinity for the interrupt to override the host's.

This is inspired by an earlier patch from Suresh Warrier, although
none of this code came from that earlier patch.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:28 +10:00
Suresh Warrier
366274f59c KVM: PPC: Book3S HV: Update irq stats for IRQs handled in real mode
When a passthrough IRQ is handled completely within KVM real
mode code, it has to also update the IRQ stats since this
does not go through the generic IRQ handling code.

However, the per CPU kstat_irqs field is an allocated (not static)
field and so cannot be directly accessed in real mode safely.

The function this_cpu_inc_rm() is introduced to safely increment
per CPU fields (currently coded for unsigned integers only) that
are allocated and could thus be vmalloced also.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:23 +10:00
Suresh Warrier
644abbb254 KVM: PPC: Book3S HV: Tunable to disable KVM IRQ bypass
Add a  module parameter kvm_irq_bypass for kvm_hv.ko to
disable IRQ bypass for passthrough interrupts. The default
value of this tunable is 1 - that is enable the feature.

Since the tunable is used by built-in kernel code, we use
the module_param_cb macro to achieve this.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:18 +10:00
Suresh Warrier
af893c7dc9 KVM: PPC: Book3S HV: Dump irqmap in debugfs
Dump the passthrough irqmap structure associated with a
guest as part of /sys/kernel/debug/powerpc/kvm-xics-*.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:13 +10:00
Suresh Warrier
f7af5209b8 KVM: PPC: Book3S HV: Complete passthrough interrupt in host
In existing real mode ICP code, when updating the virtual ICP
state, if there is a required action that cannot be completely
handled in real mode, as for instance, a VCPU needs to be woken
up, flags are set in the ICP to indicate the required action.
This is checked when returning from hypercalls to decide whether
the call needs switch back to the host where the action can be
performed in virtual mode. Note that if h_ipi_redirect is enabled,
real mode code will first try to message a free host CPU to
complete this job instead of returning the host to do it ourselves.

Currently, the real mode PCI passthrough interrupt handling code
checks if any of these flags are set and simply returns to the host.
This is not good enough as the trap value (0x500) is treated as an
external interrupt by the host code. It is only when the trap value
is a hypercall that the host code searches for and acts on unfinished
work by calling kvmppc_xics_rm_complete.

This patch introduces a special trap BOOK3S_INTERRUPT_HV_RM_HARD
which is returned by KVM if there is unfinished business to be
completed in host virtual mode after handling a PCI passthrough
interrupt. The host checks for this special interrupt condition
and calls into the kvmppc_xics_rm_complete, which is made an
exported function for this reason.

[paulus@ozlabs.org - moved logic to set r12 to BOOK3S_INTERRUPT_HV_RM_HARD
 in book3s_hv_rmhandlers.S into the end of kvmppc_check_wake_reason.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:07 +10:00
Suresh Warrier
e3c13e56a4 KVM: PPC: Book3S HV: Handle passthrough interrupts in guest
Currently, KVM switches back to the host to handle any external
interrupt (when the interrupt is received while running in the
guest). This patch updates real-mode KVM to check if an interrupt
is generated by a passthrough adapter that is owned by this guest.
If so, the real mode KVM will directly inject the corresponding
virtual interrupt to the guest VCPU's ICS and also EOI the interrupt
in hardware. In short, the interrupt is handled entirely in real
mode in the guest context without switching back to the host.

In some rare cases, the interrupt cannot be completely handled in
real mode, for instance, a VCPU that is sleeping needs to be woken
up. In this case, KVM simply switches back to the host with trap
reason set to 0x500. This works, but it is clearly not very efficient.
A following patch will distinguish this case and handle it
correctly in the host. Note that we can use the existing
check_too_hard() routine even though we are not in a hypercall to
determine if there is unfinished business that needs to be
completed in host virtual mode.

The patch assumes that the mapping between hardware interrupt IRQ
and virtual IRQ to be injected to the guest already exists for the
PCI passthrough interrupts that need to be handled in real mode.
If the mapping does not exist, KVM falls back to the default
existing behavior.

The KVM real mode code reads mappings from the mapped array in the
passthrough IRQ map without taking any lock.  We carefully order the
loads and stores of the fields in the kvmppc_irq_map data structure
using memory barriers to avoid an inconsistent mapping being seen by
the reader. Thus, although it is possible to miss a map entry, it is
not possible to read a stale value.

[paulus@ozlabs.org - get irq_chip from irq_map rather than pimap,
 pulled out powernv eoi change into a separate patch, made
 kvmppc_read_intr get the vcpu from the paca rather than being
 passed in, rewrote the logic at the end of kvmppc_read_intr to
 avoid deep indentation, simplified logic in book3s_hv_rmhandlers.S
 since we were always restoring SRR0/1 anyway, get rid of the cached
 array (just use the mapped array), removed the kick_all_cpus_sync()
 call, clear saved_xirr PACA field when we handle the interrupt in
 real mode, fix compilation with CONFIG_KVM_XICS=n.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:11:00 +10:00
Suresh Warrier
c57875f5f9 KVM: PPC: Book3S HV: Enable IRQ bypass
Add the irq_bypass_add_producer and irq_bypass_del_producer
functions. These functions get called whenever a GSI is being
defined for a guest. They create/remove the mapping between
host real IRQ numbers and the guest GSI.

Add the following helper functions to manage the
passthrough IRQ map.

kvmppc_set_passthru_irq()
  Creates a mapping in the passthrough IRQ map that maps a host
  IRQ to a guest GSI. It allocates the structure (one per guest VM)
  the first time it is called.

kvmppc_clr_passthru_irq()
  Removes the passthrough IRQ map entry given a guest GSI.
  The passthrough IRQ map structure is not freed even when the
  number of mapped entries goes to zero. It is only freed when
  the VM is destroyed.

[paulus@ozlabs.org - modified to use is_pnv_opal_msi() rather than
 requiring all passed-through interrupts to use the same irq_chip;
 changed deletion so it zeroes out the r_hwirq field rather than
 copying the last entry down and decrementing the number of entries.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:26:51 +10:00
Suresh Warrier
8daaafc88b KVM: PPC: Book3S HV: Introduce kvmppc_passthru_irqmap
This patch introduces an IRQ mapping structure, the
kvmppc_passthru_irqmap structure that is to be used
to map the real hardware IRQ in the host with the virtual
hardware IRQ (gsi) that is injected into a guest by KVM for
passthrough adapters.

Currently, we assume a separate IRQ mapping structure for
each guest. Each kvmppc_passthru_irqmap has a mapping arrays,
containing all defined real<->virtual IRQs.

[paulus@ozlabs.org - removed irq_chip field from struct
 kvmppc_passthru_irqmap; changed parameter for
 kvmppc_get_passthru_irqmap from struct kvm_vcpu * to struct
 kvm *, removed small cached array.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:26:19 +10:00
Suresh Warrier
9576730d0e KVM: PPC: select IRQ_BYPASS_MANAGER
Select IRQ_BYPASS_MANAGER for PPC when CONFIG_KVM is set.
Add the PPC producer functions for add and del producer.

[paulus@ozlabs.org - Moved new functions from book3s.c to powerpc.c
 so booke compiles; added kvm_arch_has_irq_bypass implementation.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:26:19 +10:00
Suresh Warrier
37f55d30df KVM: PPC: Book3S HV: Convert kvmppc_read_intr to a C function
Modify kvmppc_read_intr to make it a C function.  Because it is called
from kvmppc_check_wake_reason, any of the assembler code that calls
either kvmppc_read_intr or kvmppc_check_wake_reason now has to assume
that the volatile registers might have been modified.

This also adds in the optimization of clearing saved_xirr in the case
where we completely handle and EOI an IPI.  Without this, the next
device interrupt will require two trips through the host interrupt
handling code.

[paulus@ozlabs.org - made kvmppc_check_wake_reason create a stack frame
 when it is calling kvmppc_read_intr, which means we can set r12 to
 the trap number (0x500) after the call to kvmppc_read_intr, instead
 of using r31.  Also moved the deliver_guest_interrupt label so as to
 restore XER and CTR, plus other minor tweaks.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:25:25 +10:00
Paul Mackerras
99212c864e Merge branch 'kvm-ppc-infrastructure' into kvm-ppc-next
This merges the topic branch 'kvm-ppc-infrastructure' into kvm-ppc-next
so that I can then apply further patches that need the changes in the
kvm-ppc-infrastructure branch.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:24:23 +10:00
Paolo Bonzini
3f25777499 powerpc: move hmi.c to arch/powerpc/kvm/
hmi.c functions are unused unless sibling_subcore_state is nonzero, and
that in turn happens only if KVM is in use.  So move the code to
arch/powerpc/kvm/, putting it under CONFIG_KVM_BOOK3S_HV_POSSIBLE
rather than CONFIG_PPC_BOOK3S_64.  The sibling_subcore_state is also
included in struct paca_struct only if KVM is supported by the kernel.

Cc: Daniel Axtens <dja@axtens.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: kvm-ppc@vger.kernel.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:18:07 +10:00
Suraj Jitindar Singh
2a27f514a4 KVM: PPC: Implement existing and add new halt polling vcpu stats
vcpu stats are used to collect information about a vcpu which can be viewed
in the debugfs. For example halt_attempted_poll and halt_successful_poll
are used to keep track of the number of times the vcpu attempts to and
successfully polls. These stats are currently not used on powerpc.

Implement incrementation of the halt_attempted_poll and
halt_successful_poll vcpu stats for powerpc. Since these stats are summed
over all the vcpus for all running guests it doesn't matter which vcpu
they are attributed to, thus we choose the current runner vcpu of the
vcore.

Also add new vcpu stats: halt_poll_success_ns, halt_poll_fail_ns and
halt_wait_ns to be used to accumulate the total time spend polling
successfully, polling unsuccessfully and waiting respectively, and
halt_successful_wait to accumulate the number of times the vcpu waits.
Given that halt_poll_success_ns, halt_poll_fail_ns and halt_wait_ns are
expressed in nanoseconds it is necessary to represent these as 64-bit
quantities, otherwise they would overflow after only about 4 seconds.

Given that the total time spend either polling or waiting will be known and
the number of times that each was done, it will be possible to determine
the average poll and wait times. This will give the ability to tune the kvm
module parameters based on the calculated average wait and poll times.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-08 12:25:37 +10:00
Suraj Jitindar Singh
0cda69dd7c KVM: PPC: Book3S HV: Implement halt polling
This patch introduces new halt polling functionality into the kvm_hv kernel
module. When a vcore is idle it will poll for some period of time before
scheduling itself out.

When all of the runnable vcpus on a vcore have ceded (and thus the vcore is
idle) we schedule ourselves out to allow something else to run. In the
event that we need to wake up very quickly (for example an interrupt
arrives), we are required to wait until we get scheduled again.

Implement halt polling so that when a vcore is idle, and before scheduling
ourselves, we poll for vcpus in the runnable_threads list which have
pending exceptions or which leave the ceded state. If we poll successfully
then we can get back into the guest very quickly without ever scheduling
ourselves, otherwise we schedule ourselves out as before.

There exists generic halt_polling code in virt/kvm_main.c, however on
powerpc the polling conditions are different to the generic case. It would
be nice if we could just implement an arch specific kvm_check_block()
function, but there is still other arch specific things which need to be
done for kvm_hv (for example manipulating vcore states) which means that a
separate implementation is the best option.

Testing of this patch with a TCP round robin test between two guests with
virtio network interfaces has found a decrease in round trip time of ~15us
on average. A performance gain is only seen when going out of and
back into the guest often and quickly, otherwise there is no net benefit
from the polling. The polling interval is adjusted such that when we are
often scheduled out for long periods of time it is reduced, and when we
often poll successfully it is increased. The rate at which the polling
interval increases or decreases, and the maximum polling interval, can
be set through module parameters.

Based on the implementation in the generic kvm module by Wanpeng Li and
Paolo Bonzini, and on direction from Paul Mackerras.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-08 12:21:45 +10:00
Suraj Jitindar Singh
7b5f8272c7 KVM: PPC: Book3S HV: Change vcore element runnable_threads from linked-list to array
The struct kvmppc_vcore is a structure used to store various information
about a virtual core for a kvm guest. The runnable_threads element of the
struct provides a list of all of the currently runnable vcpus on the core
(those in the KVMPPC_VCPU_RUNNABLE state). The previous implementation of
this list was a linked_list. The next patch requires that the list be able
to be iterated over without holding the vcore lock.

Reimplement the runnable_threads list in the kvmppc_vcore struct as an
array. Implement function to iterate over valid entries in the array and
update access sites accordingly.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-08 12:21:44 +10:00
Paul Mackerras
4b3d173d04 KVM: PPC: Always select KVM_VFIO, plus Makefile cleanup
As discussed recently on the kvm mailing list, David Gibson's
intention in commit 178a787502 ("vfio: Enable VFIO device for
powerpc", 2016-02-01) was to have the KVM VFIO device built in
on all powerpc platforms.  This patch adds the "select KVM_VFIO"
statement that makes this happen.

Currently, arch/powerpc/kvm/Makefile doesn't include vfio.o for
the 64-bit kvm module, because the list of objects doesn't use
the $(common-objs-y) list.  The reason it doesn't is because we
don't necessarily want coalesced_mmio.o or emulate.o (for example
if HV KVM is the only target), and common-objs-y includes both.

Since this is confusing, this patch adjusts the definitions so that
we now use $(common-objs-y) in the list for the 64-bit kvm.ko
module, emulate.o is removed from common-objs-y and added in the
places that need it, and the inclusion of coalesced_mmio.o now
depends on CONFIG_KVM_MMIO.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-08-25 22:25:49 +10:00
Paul Mackerras
34a75b0f63 KVM: PPC: Implement kvm_arch_intc_initialized() for PPC
It doesn't make sense to create irqfds for a VM that doesn't have
in-kernel interrupt controller emulation.  There is an existing
interface for architecture code to tell the irqfd code whether or
not any interrupt controller has been initialized, called
kvm_arch_intc_initialized(), so let's implement that for powerpc.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-08-19 13:00:06 +10:00
Paul Mackerras
e48ba1cbce KVM: PPC: Book3S: Don't crash if irqfd used with no in-kernel XICS emulation
It turns out that if userspace creates a pseries-type VM without
in-kernel XICS (interrupt controller) emulation, and then connects
an eventfd to the VM as an irqfd, and the eventfd gets signalled,
that the code will try to deliver an interrupt via the non-existent
XICS object and crash the host kernel with a NULL pointer dereference.

To fix this, we check for the presence of the XICS object before
trying to deliver the interrupt, and return with an error if not.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-08-19 13:00:06 +10:00
Christoffer Dall
a28ebea2ad KVM: Protect device ops->create and list_add with kvm->lock
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.

Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.

The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:27 +02:00
Christoffer Dall
023e9fddc3 KVM: PPC: Move xics_debugfs_init out of create
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.

Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:26 +02:00
Linus Torvalds
f716a85cd6 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - GCC plugin support by Emese Revfy from grsecurity, with a fixup from
   Kees Cook.  The plugins are meant to be used for static analysis of
   the kernel code.  Two plugins are provided already.

 - reduction of the gcc commandline by Arnd Bergmann.

 - IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada

 - bin2c fix by Michael Tautschnig

 - setlocalversion fix by Wolfram Sang

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  gcc-plugins: disable under COMPILE_TEST
  kbuild: Abort build on bad stack protector flag
  scripts: Fix size mismatch of kexec_purgatory_size
  kbuild: make samples depend on headers_install
  Kbuild: don't add obj tree in additional includes
  Kbuild: arch: look for generated headers in obtree
  Kbuild: always prefix objtree in LINUXINCLUDE
  Kbuild: avoid duplicate include path
  Kbuild: don't add ../../ to include path
  vmlinux.lds.h: replace config_enabled() with IS_ENABLED()
  kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
  kconfig.h: use already defined macros for IS_REACHABLE() define
  export.h: use __is_defined() to check if __KSYM_* is defined
  kconfig.h: use __is_defined() to check if MODULE is defined
  kbuild: setlocalversion: print error to STDERR
  Add sancov plugin
  Add Cyclomatic complexity GCC plugin
  GCC plugin infrastructure
  Shared library support
2016-08-02 16:37:12 -04:00
Linus Torvalds
221bb8a46e - ARM: GICv3 ITS emulation and various fixes. Removal of the old
VGIC implementation.
 
 - s390: support for trapping software breakpoints, nested virtualization
 (vSIE), the STHYI opcode, initial extensions for CPU model support.
 
 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
 preliminary to this and the upcoming support for hardware virtualization
 extensions.
 
 - x86: support for execute-only mappings in nested EPT; reduced vmexit
 latency for TSC deadline timer (by about 30%) on Intel hosts; support for
 more than 255 vCPUs.
 
 - PPC: bugfixes.
 
 The ugly bit is the conflicts.  A couple of them are simple conflicts due
 to 4.7 fixes, but most of them are with other trees. There was definitely
 too much reliance on Acked-by here.  Some conflicts are for KVM patches
 where _I_ gave my Acked-by, but the worst are for this pull request's
 patches that touch files outside arch/*/kvm.  KVM submaintainers should
 probably learn to synchronize better with arch maintainers, with the
 latter providing topic branches whenever possible instead of Acked-by.
 This is what we do with arch/x86.  And I should learn to refuse pull
 requests when linux-next sends scary signals, even if that means that
 submaintainers have to rebase their branches.
 
 Anyhow, here's the list:
 
 - arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
 by the nvdimm tree.  This tree adds handle_preemption_timer and
 EXIT_REASON_PREEMPTION_TIMER at the same place.  In general all mentions
 of pcommit have to go.
 
 There is also a conflict between a stable fix and this patch, where the
 stable fix removed the vmx_create_pml_buffer function and its call.
 
 - virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
 This tree adds kvm_io_bus_get_dev at the same place.
 
 - virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
 file was completely removed for 4.8.
 
 - include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
 this is a change that should have gone in through the irqchip tree and
 pulled by kvm-arm.  I think I would have rejected this kvm-arm pull
 request.  The KVM version is the right one, except that it lacks
 GITS_BASER_PAGES_SHIFT.
 
 - arch/powerpc: what a mess.  For the idle_book3s.S conflict, the KVM
 tree is the right one; everything else is trivial.  In this case I am
 not quite sure what went wrong.  The commit that is causing the mess
 (fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
 path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
 and arch/powerpc/kvm/.  It's large, but at 396 insertions/5 deletions
 I guessed that it wasn't really possible to split it and that the 5
 deletions wouldn't conflict.  That wasn't the case.
 
 - arch/s390: also messy.  First is hypfs_diag.c where the KVM tree
 moved some code and the s390 tree patched it.  You have to reapply the
 relevant part of commits 6c22c98637, plus all of e030c1125e, to
 arch/s390/kernel/diag.c.  Or pick the linux-next conflict
 resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
 Second, there is a conflict in gmap.c between a stable fix and 4.8.
 The KVM version here is the correct one.
 
 I have pushed my resolution at refs/heads/merge-20160802 (commit
 3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:

 - ARM: GICv3 ITS emulation and various fixes.  Removal of the
   old VGIC implementation.

 - s390: support for trapping software breakpoints, nested
   virtualization (vSIE), the STHYI opcode, initial extensions
   for CPU model support.

 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots
   of cleanups, preliminary to this and the upcoming support for
   hardware virtualization extensions.

 - x86: support for execute-only mappings in nested EPT; reduced
   vmexit latency for TSC deadline timer (by about 30%) on Intel
   hosts; support for more than 255 vCPUs.

 - PPC: bugfixes.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
  KVM: PPC: Introduce KVM_CAP_PPC_HTM
  MIPS: Select HAVE_KVM for MIPS64_R{2,6}
  MIPS: KVM: Reset CP0_PageMask during host TLB flush
  MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
  MIPS: KVM: Sign extend MFC0/RDHWR results
  MIPS: KVM: Fix 64-bit big endian dynamic translation
  MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
  MIPS: KVM: Use 64-bit CP0_EBase when appropriate
  MIPS: KVM: Set CP0_Status.KX on MIPS64
  MIPS: KVM: Make entry code MIPS64 friendly
  MIPS: KVM: Use kmap instead of CKSEG0ADDR()
  MIPS: KVM: Use virt_to_phys() to get commpage PFN
  MIPS: Fix definition of KSEGX() for 64-bit
  KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
  kvm: x86: nVMX: maintain internal copy of current VMCS
  KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
  KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
  KVM: arm64: vgic-its: Simplify MAPI error handling
  KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
  KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
  ...
2016-08-02 16:11:27 -04:00
Sam Bobroff
23528bb21e KVM: PPC: Introduce KVM_CAP_PPC_HTM
Introduce a new KVM capability, KVM_CAP_PPC_HTM, that can be queried to
determine if a PowerPC KVM guest should use HTM (Hardware Transactional
Memory).

This will be used by QEMU to populate the pa-features bits in the
guest's device tree.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-08-01 19:42:06 +02:00
Paul Mackerras
93d17397e4 KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
It turns out that if the guest does a H_CEDE while the CPU is in
a transactional state, and the H_CEDE does a nap, and the nap
loses the architected state of the CPU (which is is allowed to do),
then we lose the checkpointed state of the virtual CPU.  In addition,
the transactional-memory state recorded in the MSR gets reset back
to non-transactional, and when we try to return to the guest, we take
a TM bad thing type of program interrupt because we are trying to
transition from non-transactional to transactional with a hrfid
instruction, which is not permitted.

The result of the program interrupt occurring at that point is that
the host CPU will hang in an infinite loop with interrupts disabled.
Thus this is a denial of service vulnerability in the host which can
be triggered by any guest (and depending on the guest kernel, it can
potentially triggered by unprivileged userspace in the guest).

This vulnerability has been assigned the ID CVE-2016-5412.

To fix this, we save the TM state before napping and restore it
on exit from the nap, when handling a H_CEDE in real mode.  The
case where H_CEDE exits to host virtual mode is already OK (as are
other hcalls which exit to host virtual mode) because the exit
path saves the TM state.

Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-07-28 16:10:07 +10:00
Paul Mackerras
f024ee0984 KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
This moves the transactional memory state save and restore sequences
out of the guest entry/exit paths into separate procedures.  This is
so that these sequences can be used in going into and out of nap
in a subsequent patch.

The only code changes here are (a) saving and restore LR on the
stack, since these new procedures get called with a bl instruction,
(b) explicitly saving r1 into the PACA instead of assuming that
HSTATE_HOST_R1(r13) is already set, and (c) removing an unnecessary
and redundant setting of MSR[TM] that should have been removed by
commit 9d4d0bdd9e0a ("KVM: PPC: Book3S HV: Add transactional memory
support", 2013-09-24) but wasn't.

Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-07-28 16:09:34 +10:00
Benjamin Herrenschmidt
7025776ed1 powerpc/mm: Move hash table ops to a separate structure
Moving probe_machine() to after mmu init will cause the ppc_md
fields relative to the hash table management to be overwritten.

Since we have essentially disconnected the machine type from
the hash backend ops, finish the job by moving them to a different
structure.

The only callback that didn't quite fix is update_partition_table
since this is not specific to hash, so I moved it to a standalone
variable for now. We can revisit later if needed.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Fix ppc64e build failure in kexec]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-21 18:59:09 +10:00
Benjamin Herrenschmidt
d3cbff1b5a powerpc: Put exception configuration in a common place
The various calls to establish exception endianness and AIL are
now done from a single point using already established CPU and FW
feature bits to decide what to do.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-21 18:56:31 +10:00
Arnd Bergmann
58ab5e0c2c Kbuild: arch: look for generated headers in obtree
There are very few files that need add an -I$(obj) gcc for the preprocessor
or the assembler. For C files, we add always these for both the objtree and
srctree, but for the other ones we require the Makefile to add them, and
Kbuild then adds it for both trees.

As a preparation for changing the meaning of the -I$(obj) directive to
only refer to the srctree, this changes the two instances in arch/x86 to use
an explictit $(objtree) prefix where needed, otherwise we won't find the
headers any more, as reported by the kbuild 0day builder.

arch/x86/realmode/rm/realmode.lds.S:75:20: fatal error: pasyms.h: No such file or directory

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-07-18 21:31:35 +02:00
Shreyas B. Prabhu
5fa6b6bd7a powerpc/powernv: Rename reusable idle functions to hardware agnostic names
Functions like power7_wakeup_loss, power7_wakeup_noloss,
power7_wakeup_tb_loss are used by POWER7 and POWER8 hardware. They can
also be used by POWER9. Hence rename these functions hardware agnostic
names.

Suggested-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-15 20:18:39 +10:00
Daniel Axtens
f8750513b7 powerpc/kvm: Clarify __user annotations
kvmppc_h_put_tce_indirect labels a u64 pointer as __user. It also
labelled the u64 where get_user puts the result as __user. This isn't
a pointer and so doesn't need to be labelled __user.

Split the u64 value definition onto a new line to make it clear that
it doesn't get the annotation.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-14 20:43:50 +10:00
Radim Krčmář
c63cf538eb KVM: pass struct kvm to kvm_set_routing_entry
Arch-specific code will use it.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:56 +02:00
Paolo Bonzini
6d5315b3a6 Merge branch 'kvm-ppc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD 2016-07-11 18:10:06 +02:00
Paolo Bonzini
6edaa5307f KVM: remove kvm_guest_enter/exit wrappers
Use the functions from context_tracking.h directly.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:21 +02:00
Mahesh Salgaonkar
fd7bacbca4 KVM: PPC: Book3S HV: Fix TB corruption in guest exit path on HMI interrupt
When a guest is assigned to a core it converts the host Timebase (TB)
into guest TB by adding guest timebase offset before entering into
guest. During guest exit it restores the guest TB to host TB. This means
under certain conditions (Guest migration) host TB and guest TB can differ.

When we get an HMI for TB related issues the opal HMI handler would
try fixing errors and restore the correct host TB value. With no guest
running, we don't have any issues. But with guest running on the core
we run into TB corruption issues.

If we get an HMI while in the guest, the current HMI handler invokes opal
hmi handler before forcing guest to exit. The guest exit path subtracts
the guest TB offset from the current TB value which may have already
been restored with host value by opal hmi handler. This leads to incorrect
host and guest TB values.

With split-core, things become more complex. With split-core, TB also gets
split and each subcore gets its own TB register. When a hmi handler fixes
a TB error and restores the TB value, it affects all the TB values of
sibling subcores on the same core. On TB errors all the thread in the core
gets HMI. With existing code, the individual threads call opal hmi handle
independently which can easily throw TB out of sync if we have guest
running on subcores. Hence we will need to co-ordinate with all the
threads before making opal hmi handler call followed by TB resync.

This patch introduces a sibling subcore state structure (shared by all
threads in the core) in paca which holds information about whether sibling
subcores are in Guest mode or host mode. An array in_guest[] of size
MAX_SUBCORE_PER_CORE=4 is used to maintain the state of each subcore.
The subcore id is used as index into in_guest[] array. Only primary
thread entering/exiting the guest is responsible to set/unset its
designated array element.

On TB error, we get HMI interrupt on every thread on the core. Upon HMI,
this patch will now force guest to vacate the core/subcore. Primary
thread from each subcore will then turn off its respective bit
from the above bitmap during the guest exit path just after the
guest->host partition switch is complete.

All other threads that have just exited the guest OR were already in host
will wait until all other subcores clears their respective bit.
Once all the subcores turn off their respective bit, all threads will
will make call to opal hmi handler.

It is not necessary that opal hmi handler would resync the TB value for
every HMI interrupts. It would do so only for the HMI caused due to
TB errors. For rest, it would not touch TB value. Hence to make things
simpler, primary thread would call TB resync explicitly once for each
core immediately after opal hmi handler instead of subtracting guest
offset from TB. TB resync call will restore the TB with host value.
Thus we can be sure about the TB state.

One of the primary threads exiting the guest will take up the
responsibility of calling TB resync. It will use one of the top bits
(bit 63) from subcore state flags bitmap to make the decision. The first
primary thread (among the subcores) that is able to set the bit will
have to call the TB resync. Rest all other threads will wait until TB
resync is complete.  Once TB resync is complete all threads will then
proceed.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-06-20 14:11:25 +10:00
Thomas Huth
b69890d18f KVM: PPC: Book3S PR: Fix contents of SRR1 when injecting a program exception
vcpu->arch.shadow_srr1 only contains usable values for injecting
a program exception into the guest if we entered the function
kvmppc_handle_exit_pr() with exit_nr == BOOK3S_INTERRUPT_PROGRAM.
In other cases, the shadow_srr1 bits are zero. Since we want to
pass an illegal-instruction program check to the guest, set
"flags" to SRR1_PROGILL for these other cases.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-06-20 14:11:25 +10:00
Thomas Huth
708e75a3ee KVM: PPC: Book3S PR: Fix illegal opcode emulation
If kvmppc_handle_exit_pr() calls kvmppc_emulate_instruction() to emulate
one instruction (in the BOOK3S_INTERRUPT_H_EMUL_ASSIST case), it calls
kvmppc_core_queue_program() afterwards if kvmppc_emulate_instruction()
returned EMULATE_FAIL, so the guest gets an program interrupt for the
illegal opcode.
However, the kvmppc_emulate_instruction() also tried to inject a
program exception for this already, so the program interrupt gets
injected twice and the return address in srr0 gets destroyed.
All other callers of kvmppc_emulate_instruction() are also injecting
a program interrupt, and since the callers have the right knowledge
about the srr1 flags that should be used, it is the function
kvmppc_emulate_instruction() that should _not_ inject program
interrupts, so remove the kvmppc_core_queue_program() here.

This fixes the issue discovered by Laurent Vivier with kvm-unit-tests
where the logs are filled with these messages when the test tries
to execute an illegal instruction:

     Couldn't emulate instruction 0x00000000 (op 0 xop 0)
     kvmppc_handle_exit_pr: emulation at 700 failed (00000000)

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-06-20 14:11:25 +10:00