If the host has both KVM PR and KVM HV loaded and we pass:
-machine pseries,accel=kvm,kvm-type=PR
the kvmppc_is_pr() returns false instead of true. Since the helper
is mostly used as fallback, it doesn't have any real impact with
recent kernels. A notable exception is the workaround to allow
migration between compatible hosts with different PVRs (eg, POWER8
and POWER8E), since KVM still doesn't provide a way to check if a
specific PVR is supported (see commit c363a37a45 for details).
According to the official KVM API documentation [1], KVM_PPC_GET_PVINFO
is "vm ioctl", but we check it as a global ioctl. The following function
in KVM is hence called with kvm == NULL and considers we're in HV mode.
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int r;
/* Assume we're using HV mode when the HV module is loaded */
int hv_enabled = kvmppc_hv_ops ? 1 : 0;
if (kvm) {
/*
* Hooray - we know which VM type we're running on. Depend on
* that rather than the guess above.
*/
hv_enabled = is_kvmppc_hv_enabled(kvm);
}
Let's use kvm_vm_check_extension() to fix the issue.
[1] https://www.kernel.org/doc/Documentation/virtual/kvm/api.txt
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>
Caching there practically doesn't give any benefits
and that at slow path druring querying supported CPU list.
But it introduces non conventional path of where from
comes used CPU type name (kvm_ppc_register_host_cpu_type).
Taking in account that kvm_ppc_register_host_cpu_type()
fixes up models the aliases point to, it's sufficient to
make ppc_cpu_class_by_name() translate cpu alias to
correct cpu type name.
So drop PowerPCCPUAlias::oc field + ppc_cpu_class_by_alias()
and let ppc_cpu_class_by_name() do conversion to cpu type name,
which simplifies code a little bit saving ~20LOC and trouble
wondering why ppc_cpu_class_by_alias() is necessary.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
PPC handles -cpu FOO rather incosistently,
i.e. it does case-insensitive matching of FOO to
a CPU type (see: ppc_cpu_compare_class_name) but
handles alias names as case-sensitive, as result:
# qemu-system-ppc64 -M mac99 -cpu g3
qemu-system-ppc64: unable to find CPU model ' kN�U'
# qemu-system-ppc64 -cpu 970MP_V1.1
qemu-system-ppc64: Unable to find sPAPR CPU Core definition
while
# qemu-system-ppc64 -M mac99 -cpu G3
# qemu-system-ppc64 -cpu 970MP_v1.1
start up just fine.
Considering we can't take case-insensitive matching away,
make it case-insensitive for all alias/type/core_type
lookups.
As side effect it allows to remove duplicate core types
which are the same except of using different cased letters in name.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Replace
"-" TYPE_POWERPC_CPU
when composing cpu type name from cpu model string literal
and the same pattern in format strings with
POWERPC_CPU_TYPE_SUFFIX and POWERPC_CPU_TYPE_NAME(model)
macroses like we do in x86.
Later POWERPC_CPU_TYPE_NAME() will be used to define default
cpu type per machine type and as bonus it will be consistent
and easy grep-able pattern across all other targets that I'm
plannig to treat the same way.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
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>
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>
This field actually records the VCPU ID used by KVM and, although the
value is also used in the device tree it is primarily the VCPU ID so
rename it as such.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Updated comment missed in cpu.h]
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit d5fc133eed ("ppc: Rework CPU compatibility testing
across migration") changed the way cpu_post_load behaves with
the PVR setting, causing an unexpected bug in KVM-HV migrations
between hosts that are compatible (POWER8 and POWER8E, for example).
Even with pvr_match() returning true, the guest freezes right after
cpu_post_load. The reason is that the guest kernel can't handle a
different PVR value other that the running host in KVM_SET_SREGS.
In [1] it was discussed the possibility of a new KVM capability
that would indicate that the guest kernel can handle a different
PVR in KVM_SET_SREGS. Even if such feature is implemented, there is
still the problem with older kernels that will not have this capability
and will fail to migrate.
This patch implements a workaround for that scenario. If running
with KVM, check if the guest kernel does not have the capability
(named here as 'cap_ppc_pvr_compat'). If it doesn't, calls
kvmppc_is_pr() to see if the guest is running in KVM-HV. If all this
happens, set env->spr[SPR_PVR] to the same value as the current
host PVR. This ensures that we allow migrations with 'close enough'
PVRs to still work in KVM-HV but also makes the code ready for
this new KVM capability when it is done.
A new function called 'kvmppc_pvr_workaround_required' was created
to encapsulate the conditions said above and to avoid calling too
many kvm.c internals inside cpu_post_load.
[1] https://lists.gnu.org/archive/html/qemu-ppc/2017-06/msg00503.html
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
[dwg: Fix for the case of using TCG on a PPC host]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
So far, qemu implements the PAPR Hash Page Table (HPT) resizing extension
with TCG. The same implementation will work with KVM PR, but we don't
currently allow that. For KVM HV we can only implement resizing with the
assistance of the host kernel, which needs a new capability and ioctl()s.
This patch adds support for testing the new KVM capability and implementing
the resize in terms of KVM facilities when necessary. If we're running on
a kernel which doesn't have the new capability flag at all, we fall back to
testing for PR vs. HV KVM using the same hack that we already use in a
number of places for older kernels.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
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>
When running KVM on POWER, we allow the user to pass "-cpu POWERx" instead
of "-cpu host". This is achieved by patching the ppc_cpu_aliases[] array
so that "POWERx" points to the CPU class with the same PVR as the host CPU.
This causes CPUs to be instantiated from this CPU class instead of the
TYPE_HOST_POWERPC_CPU class which is used with "-cpu host". These CPUs thus
miss all the KVM specific tuning from kvmppc_host_cpu_class_init().
This currently causes QEMU with "-cpu POWER9" to fail when running KVM on a
POWER9 DD1 host:
qemu-system-ppc64: Register sync failed... If you're using kvm-hv.ko, only
"-cpu host" is possible
kvm_init_vcpu failed: Invalid argument
Let's have the "POWERx" alias to point to TYPE_HOST_POWERPC_CPU directly,
so that "-cpu POWERx" instantiates CPUs from the same class as "-cpu host".
Signed-off-by: Greg Kurz <groug@kaod.org>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The string returned by object_property_get_str() is dynamically allocated.
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>
This function has three implementations. Two are stubs that do nothing
and the third one only passes the obj_path argument to:
Object *object_resolve_path(const char *path, bool *ambiguous);
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When running with KVM, we update the "family" CPU alias to point
to the right host CPU type, so that it for example possible to
use "-cpu POWER8" on a POWER8NVL host. However, the function for
printing the list of available CPU models is called earlier than
the KVM setup code, so the output of "-cpu help" is wrong in that
case. Since it would be somewhat ugly anyway to have different
help texts depending on whether "-enable-kvm" has been specified
or not, we should better always print the same text, so fix this
issue by printing "alias for preferred XXX CPU" instead.
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
POWER9 DD1 silicon has some bugs which mean it a) isn't really compliant
with the ISA v3.00 and b) require a number of special workarounds in the
kernel.
At the moment, qemu isn't aware of DD1. For TCG we don't really want it to
be (why bother emulating buggy silicon). But with KVM, the guest does need
to be aware of DD1 so it can apply the necessary workarounds.
Meanwhile, the feature negotiation between qemu and the guest strongly
favours architected compatibility modes to "raw" CPU modes. In combination
with the above, this means the guest sees architected POWER9 mode, and
doesn't apply the DD1 workarounds. Well, unless it has yet another
workaround to partially ignore what qemu tells it.
This patch addresses this by disabling support for compatibility modes when
using KVM on a POWER9 DD1 host.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This enables in-kernel handling of H_PUT_TCE_INDIRECT and
H_STUFF_TCE hypercalls. The host kernel support is there since v4.6,
in particular d3695aa4f452
("KVM: PPC: Add support for multiple-TCE hcalls").
H_PUT_TCE is already accelerated and does not need any special enablement.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The H_REGISTER_PROCESS_TABLE H_CALL is used by a guest to indicate to the
hypervisor where in memory its process table is and how translation should
be performed using this process table.
Provide the implementation of this H_CALL for a guest.
We first check for invalid flags, then parse the flags to determine the
operation, and then check the other parameters for valid values based on
the operation (register new table/deregister table/maintain registration).
The process table is then stored in the appropriate location and registered
with the hypervisor (if running under KVM), and the LPCR_[UPRT/GTSE] bits
are updated as required.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Correct missing prototype and uninitialized variable]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Query and cache the value of two new KVM capabilities that indicate
KVM's support for new radix and hash modes of the MMU.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Use the new ioctl, KVM_PPC_GET_RMMU_INFO, to fetch radix MMU
information from KVM and present the page encodings in the device tree
under ibm,processor-radix-AP-encodings. This provides page size
information to the guest which is necessary for it to use radix mode.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Compile fix for 32-bit targets, style nit fix]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
KVM_CAP_SPAPR_TCE capability allows creating TCE tables in KVM which
allows having in-kernel acceleration for H_PUT_TCE_xxx hypercalls.
However it only supports 32bit DMA windows at zero bus offset.
There is a new KVM_CAP_SPAPR_TCE_64 capability which supports 64bit
window size, variable page size and bus offset.
This makes use of the new capability. The kernel headers are already
updated as the kernel support went in to v4.6.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
On Power8 hosts it is currently theoretically possible for QEMU/KVM-HV guests
to receive a ibm,pa-features property indicating that HTM support is available
when it is not. The situation would occur if the platform firmware of
a Power8 host cleared the HTM bit of the ibm,pa-features property.
QEMU would query KVM for the availability of HTM, which will return no
support, but workaround code in kvm_arch_init_vcpu() would then
re-enable it because KVM_HV is in use and the processor is P8.
This patch adjusts the workaround in kvm_arch_init_vcpu() so that it does not
enable HTM (in the above case) unless the host kernel indicates to the QEMU
process, via the auxiliary vector, that userspace can use HTM (via the HWCAP2
bit KVM_FEATURE2_HTM).
The reason to use the value from the auxiliary vector is that it is
set based only on what the host kernel found in the ibm,pa-features
HTM bit at boot time.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This removes the assert(kvm_enabled()) from kvmppc_host_cpu_initfn()
This assert can never be triggered as the function is only registered
when KVM is available (see also 4c315c2
"qdev: Protect device-list-properties against broken devices").
So we can remove the cannot_destroy_with_object_finalize_yet from
kvmppc_host_cpu_class_init() without fear and beyond reproach.
(as it has already be done for i386 with 771a13e "i386: Unset
cannot_destroy_with_object_finalize_yet on "host" model" and
e435601 "target-i386: Remove assert(kvm_enabled()) from
host_x86_cpu_initfn()")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170414083717.13641-3-lvivier@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This will probably be my last pull request before the hard freeze. It
has some new work, but that has all been posted in draft before the
soft freeze, so I think it's reasonable to include in qemu-2.9.
This batch has:
* A substantial amount of POWER9 work
* Implements the legacy (hash) MMU for POWER9
* Some more preliminaries for implementing the POWER9 radix
MMU
* POWER9 has_work
* Basic POWER9 compatibility mode handling
* Removal of some premature tests
* Some cleanups and fixes to the existing MMU code to make the
POWER9 work simpler
* A bugfix for TCG multiply adds on power
* Allow pseries guests to access PCIe extended config space
This also includes a code-motion not strictly in ppc code - moving
getrampagesize() from ppc code to exec.c. This will make some future
VFIO improvements easier, Paolo said it was ok to merge via my tree.
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Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-2.9-20170303' into staging
ppc patch queuye for 2017-03-03
This will probably be my last pull request before the hard freeze. It
has some new work, but that has all been posted in draft before the
soft freeze, so I think it's reasonable to include in qemu-2.9.
This batch has:
* A substantial amount of POWER9 work
* Implements the legacy (hash) MMU for POWER9
* Some more preliminaries for implementing the POWER9 radix
MMU
* POWER9 has_work
* Basic POWER9 compatibility mode handling
* Removal of some premature tests
* Some cleanups and fixes to the existing MMU code to make the
POWER9 work simpler
* A bugfix for TCG multiply adds on power
* Allow pseries guests to access PCIe extended config space
This also includes a code-motion not strictly in ppc code - moving
getrampagesize() from ppc code to exec.c. This will make some future
VFIO improvements easier, Paolo said it was ok to merge via my tree.
# gpg: Signature made Fri 03 Mar 2017 03:20:36 GMT
# gpg: using RSA key 0x6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg: aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg: aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg: aka "David Gibson (kernel.org) <dwg@kernel.org>"
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E 87DC 6C38 CACA 20D9 B392
* remotes/dgibson/tags/ppc-for-2.9-20170303:
target/ppc: rewrite f[n]m[add,sub] using float64_muladd
spapr: Small cleanup of PPC MMU enums
spapr_pci: Advertise access to PCIe extended config space
target/ppc: Rework hash mmu page fault code and add defines for clarity
target/ppc: Move no-execute and guarded page checking into new function
target/ppc: Add execute permission checking to access authority check
target/ppc: Add Instruction Authority Mask Register Check
hw/ppc/spapr: Add POWER9 to pseries cpu models
target/ppc/POWER9: Add cpu_has_work function for POWER9
target/ppc/POWER9: Add POWER9 pa-features definition
target/ppc/POWER9: Add POWER9 mmu fault handler
target/ppc: Don't gen an SDR1 on POWER9 and rework register creation
target/ppc: Add patb_entry to sPAPRMachineState
target/ppc/POWER9: Add POWERPC_MMU_V3 bit
powernv: Don't test POWER9 CPU yet
exec, kvm, target-ppc: Move getrampagesize() to common code
target/ppc: Add POWER9/ISAv3.00 to compat_table
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Call kvm_on_sigbus_vcpu asynchronously from the VCPU thread.
Information for the SIGBUS can be stored in thread-local variables
and processed later in kvm_cpu_exec.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Build it on kvm_arch_on_sigbus_vcpu instead. They do the same
for "action optional" SIGBUSes, and the main thread should never get
"action required" SIGBUSes because it blocks the signal.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The PPC MMU types are sometimes treated as if they were a bit field
and sometime as if they were an enum which causes maintenance
problems: flipping bits in the MMU type (which is done on both the 1TB
segment and 64K segment bits) currently produces new MMU type
values that are not handled in every "switch" on it, sometimes causing
an abort().
This patch provides some macros that can be used to filter out the
"bit field-like" bits so that the remainder of the value can be
switched on, like an enum. This allows removal of all of the
"degraded" types from the list and should ease maintenance.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
getrampagesize() returns the largest supported page size and mainly
used to know if huge pages are enabled.
However is implemented in target-ppc/kvm.c and not available
in TCG or other architectures.
This renames and moves gethugepagesize() to mmap-alloc.c where
fd-based analog of it is already implemented. This renames and moves
getrampagesize() to exec.c as it seems to be the common place for
helpers like this.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The pseries machine type implements the behaviour of a PAPR compliant
hypervisor, without actually executing such a hypervisor on the virtual
CPU. To do this we need some hooks in the CPU code to make hypervisor
facilities get redirected to the machine instead of emulated internally.
For hypercalls this is managed through the cpu->vhyp field, which points
to a QOM interface with a method implementing the hypercall.
For the hashed page table (HPT) - also a hypervisor resource - we use an
older hack. CPUPPCState has an 'external_htab' field which when non-NULL
indicates that the HPT is stored in qemu memory, rather than within the
guest's address space.
For consistency - and to make some future extensions easier - this merges
the external HPT mechanism into the vhyp mechanism. Methods are added
to vhyp for the basic operations the core hash MMU code needs: map_hptes()
and unmap_hptes() for reading the HPT, store_hpte() for updating it and
hpt_mask() to retrieve its size.
To match this, the pseries machine now sets these vhyp fields in its
existing vhyp class, rather than reaching into the cpu object to set the
external_htab field.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
When a 'pseries' guest is running with KVM-HV, the guest's hashed page
table (HPT) is stored within the host kernel, so it is not directly
accessible to qemu. Most of the time, qemu doesn't need to access it:
we're using the hardware MMU, and KVM itself implements the guest
hypercalls for manipulating the HPT.
However, qemu does need access to the in-KVM HPT to implement
get_phys_page_debug() for the benefit of the gdbstub, and maybe for
other debug operations.
To allow this, 7c43bca "target-ppc: Fix page table lookup with kvm
enabled" added kvmppc_hash64_read_pteg() to target/ppc/kvm.c to read
in a batch of HPTEs from the KVM table. Unfortunately, there are a
couple of problems with this:
First, the name of the function implies it always reads a whole PTEG
from the HPT, but in fact in some cases it's used to grab individual
HPTEs (which ends up pulling 8 HPTEs, not aligned to a PTEG from the
kernel).
Second, and more importantly, the code to read the HPTEs from KVM is
simply wrong, in general. The data from the fd that KVM provides is
designed mostly for compact migration rather than this sort of one-off
access, and so needs some decoding for this purpose. The current code
will work in some cases, but if there are invalid HPTEs then it will
not get sane results.
This patch rewrite the HPTE reading function to have a simpler
interface (just read n HPTEs into a caller provided buffer), and to
correctly decode the stream from the kernel.
For consistency we also clean up the similar function for altering
HPTEs within KVM (introduced in c138593 "target-ppc: Update
ppc_hash64_store_hpte to support updating in-kernel htab").
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
On POWER, the valid page sizes that the guest can use are bound
to the CPU and not to the memory region. QEMU already has some
fancy logic to find out the right maximum memory size to tell
it to the guest during boot (see getrampagesize() in the file
target/ppc/kvm.c for more information).
However, once we're booted and the guest is using huge pages
already, it is currently still possible to hot-plug memory regions
that does not support huge pages - which of course does not work
on POWER, since the guest thinks that it is possible to use huge
pages everywhere. The KVM_RUN ioctl will then abort with -EFAULT,
QEMU spills out a not very helpful error message together with
a register dump and the user is annoyed that the VM unexpectedly
died.
To avoid this situation, we should check the page size of hot-plugged
DIMMs to see whether it is possible to use it in the current VM.
If it does not fit, we can print out a better error message and
refuse to add it, so that the VM does not die unexpectely and the
user has a second chance to plug a DIMM with a matching memory
backend instead.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1419466
Signed-off-by: Thomas Huth <thuth@redhat.com>
[dwg: Fix a build error on 32-bit builds with KVM]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When running with KVM on POWER, we are registering a "family" CPU
type for the host CPU that we are running on. For example, on all
POWER8-compatible hosts, we register a "POWER8" CPU type, so that
you can always start QEMU with "-cpu POWER8" there, without the
need to know whether you are running on a POWER8, POWER8E or POWER8NVL
host machine.
However, we also have a "POWER8" CPU alias in the ppc_cpu_aliases list
(that is mainly useful for TCG). This leads to two cosmetical drawbacks:
If the user runs QEMU with "-cpu ?", we always claim that POWER8 is an
"alias for POWER8_v2.0" - which is simply not true when running with
KVM on POWER. And when using the 'query-cpu-definitions' QMP call,
there are currently two entries for "POWER8", one for the alias, and
one for the additional registered type.
To solve the two problems, we should rather update the "family" alias
instead of registering a new types. We then only have one "POWER8"
CPU definition around, an alias, which also points to the right
destination.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1396536
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The 'cpu_version' field in PowerPCCPU is badly named. It's named after the
'cpu-version' device tree property where it is advertised, but that meaning
may not be obvious in most places it appears.
Worse, it doesn't even really correspond to that device tree property. The
property contains either the processor's PVR, or, if the CPU is running in
a compatibility mode, a special "logical PVR" representing which mode.
Rename the cpu_version field, and a number of related variables to
compat_pvr to make this clearer.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Move the generic cpu_synchronize_ functions to the common hw_accel.h header,
in order to prepare for the addition of a second hardware accelerator.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Message-Id: <f5c3cffe8d520011df1c2e5437bb814989b48332.1484045952.git.vpalatin@chromium.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [crisµblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
