Both were added in Ivy Bridge (for which we do not have a CPU model
yet!).
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
vm86 mode extensions date back to the 486. All models should have
them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add xsaves related definition, it also adds corresponding part
to kvm_get/put, and vmstate.
Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These represent xsave-related capabilities of the processor, and KVM may
or may not support them.
Add feature bits so that they are considered by "-cpu ...,enforce", and use
the new feature work instead of calling kvm_arch_get_supported_cpuid.
Bit 3 (XSAVES) is not migratables because it requires saving MSR_IA32_XSS.
Neither KVM nor any commonly available hardware supports it anyway.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After the next patch, if a masked PIC interrupts causes CPU_INTERRUPT_POLL
to be set, the CPU will spuriously get out of halted state. While this
is technically valid, we should avoid that.
Make CPU_INTERRUPT_POLL run apic_update_irq in the right thread and then
look at CPU_INTERRUPT_HARD. If CPU_INTERRUPT_HARD does not get set,
do not report the CPU as having work.
Also move the handling of software-disabled APIC from apic_update_irq
to apic_irq_pending, and always trigger CPU_INTERRUPT_POLL. This will
be important once we will add a case that resets CPU_INTERRUPT_HARD
from apic_update_irq. We want to run it even if we go through
CPU_INTERRUPT_POLL, and even if the local APIC is software disabled.
Reported-by: Richard Bilson <rbilson@qnx.com>
Tested-by: Richard Bilson <rbilson@qnx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Merge remote-tracking branch 'remotes/mjt/tags/pull-trivial-patches-2014-11-11' into staging
trivial patches for 2014-11-11
# gpg: Signature made Tue 11 Nov 2014 14:38:39 GMT using RSA key ID A4C3D7DB
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg: aka "Michael Tokarev <mjt@corpit.ru>"
# gpg: aka "Michael Tokarev <mjt@debian.org>"
* remotes/mjt/tags/pull-trivial-patches-2014-11-11:
block: Fix comment for bdrv_co_get_block_status
sysbus: Correct SYSTEM_BUS(obj) defines
target-i386: cpu: keeping function parameters alignment on new line
xen-hvm: Remove redundant variable 'xstate'
coroutine-sigaltstack: Change jmp_buf to sigjmp_buf
pc-bios: petalogix-s3adsp1800.dtb: Use 'xlnx, xps-ethernetlite-2.00.a' instead of 'xlnx, xps-ethernetlite-2.00.b'
gdbstub: Add a missing case of signal number translation in gdbstub
numa: make 'info numa' take into account hotplugged memory
slirp/smbd: modify/set several parameters in generated smbd.conf
qemu-doc.texi: fix typos in x509 examples
icc_bus: fix typo ICC_BRIGDE -> ICC_BRIDGE
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Make SVM be disabled by default on all CPU models when in KVM mode.
Nested SVM is enabled by default in the KVM kernel module, but it is
probably less stable than nested VMX (which is already disabled by
default).
Add a new compat function, x86_cpu_compat_kvm_no_autodisable(), to keep
compatibility on previous machine-types.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
TCG doesn't support VMX, and nested VMX is not enabled by default in the
KVM kernel module.
So, there's no reason to have VMX enabled by default on the core2duo and
coreduo CPU models, today. Even the newer Intel CPU model definitions
don't have it enabled.
In this case, we need machine-type compat code, as people may be running
the older machine-types on hosts that had VMX nesting enabled.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
The following CPU features were never supported by neither TCG or KVM,
so they are useless on the CPU model definitions, today:
* CPUID_DTS (DS)
* CPUID_HT
* CPUID_TM
* CPUID_PBE
* CPUID_EXT_DTES64
* CPUID_EXT_DSCPL
* CPUID_EXT_EST
* CPUID_EXT_TM2
* CPUID_EXT_XTPR
* CPUID_EXT_PDCM
* CPUID_SVM_LBRV
As using "enforce" mode is the only way to ensure guest ABI doesn't
change when moving to a different host, we should make "enforce" mode
the default or at least encourage management software to always use it.
In turn, to make "enforce" usable, we need CPU models that work without
always requiring some features to be explicitly disabled. This patch
removes the above features from all CPU model definitions.
We won't need any machine-type compat code for those changes, because it
is impossible to have existing VMs with those features enabled.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Andreas Färber <afaerber@suse.de>
KVM never supported the CPUID_ACPI flag, so it doesn't make sense to
have it enabled by default when KVM is enabled.
The motivation here is exactly the same we had for the MONITOR flag
(disabled by commit 136a7e9a85).
And like in the MONITOR flag case, we don't need machine-type compat code
because it is currently impossible to run a KVM VM with the ACPI flag set.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
The x86_cpu_compat_disable_kvm_features() name was a bit confusing, as
it won't forcibly disable the feature for all CPU models (i.e. add it to
kvm_default_unset_features), but it will instead turn off the KVM
auto-enabling of the feature (i.e. remove it from kvm_default_features),
meaning the feature may still be enabled by default in some CPU models).
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
The struct is not used anymore and can be removed.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Only Intel CPUs support hyperthreading. When users select threads>1 in
-smp option, QEMU fixes it by adjusting CPUID_0000_0001_EBX and
CPUID_8000_0008_ECX based on inputs (sockets, cores, threads);
so guest VM can boot correctly. However it is still better to gives
users a warning when such case happens.
Signed-off-by: Wei Huang <wei@redhat.com>
[As suggested by Eduardo, check for !IS_INTEL instead of AMD. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvmclock fix. This was reverted last minute for 2.1, but it is now back
with the problematic case fixed.
Note: I will soon switch to a subkey for signing purposes. To verify
future signed pull requests from me, please update my key with
"gpg --recv-keys 9B4D86F2". You should see 3 new subkeys---the
one for signing will be a 2048-bit RSA key, 4E6B09D7.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
Usual mix of patches, the most important being Alex and Marcelo's
kvmclock fix. This was reverted last minute for 2.1, but it is now back
with the problematic case fixed.
Note: I will soon switch to a subkey for signing purposes. To verify
future signed pull requests from me, please update my key with
"gpg --recv-keys 9B4D86F2". You should see 3 new subkeys---the
one for signing will be a 2048-bit RSA key, 4E6B09D7.
# gpg: Signature made Fri 26 Sep 2014 15:34:44 BST using RSA key ID 9B4D86F2
# gpg: Good signature from "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: aka "Paolo Bonzini <bonzini@gnu.org>"
* remotes/bonzini/tags/for-upstream:
kvm/valgrind: don't mark memory as initialized
po: fix conflict with %.mo rule in rules.mak
kvmvapic: fix migration when VM paused and when not running Windows
serial: check if backed by a physical serial port at realize time
serial: reset state at startup
target-i386: update fp status fix
hw/dma/i8257: Silence phony error message
kvmclock: Ensure time in migration never goes backward
kvmclock: Ensure proper env->tsc value for kvmclock_current_nsec calculation
Introduce cpu_clean_all_dirty
pit: fix pit interrupt can't inject into vm after migration
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Note that the code that was within the "exit" ifdef block
was identical to the cpu_compute_eflags inline, so make that
simplification at the same time.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-4-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch introduces cpu_set_fpuc() function, which changes fpuc field
of the CPU state and calls update_fp_status() function.
These calls update status of softfloat library and prevent bugs caused
by non-coherent rounding settings of the FPU and softfloat.
v2 changes:
* Added missed calls and intoduced setter function (as suggested by TeLeMan)
Reviewed-by: TeLeMan <geleman@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Instead of simply printing a warning, report an error when invalid CPU
options are provided on the CPU model string.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
When the "migratable" property was implemented, the behavior was tested
by changing the default on the code, but actually using the option on
the command-line (e.g. "-cpu host,migratable=false") doesn't work as
expected. This is a regression for a common use case of "-cpu host",
which is to enable features that are supported by the host CPU + kernel
before feature-specific code is added to QEMU.
Fix this by initializing the feature words for "-cpu host" on
x86_cpu_parse_featurestr(), right after parsing the CPU options.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Andreas Färber <afaerber@suse.de>
tsc_adjust migration support is already implemented (commit
f28558d3d3), so we can add it to the list
of known feature names.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Migration support for MPX is already implemented (commit
79e9ebebbf), so we can add it to the list
of known feature names.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The SDM specifies (June 2014 Vol3 11.11.5):
On a hardware reset, the P6 and more recent processors clear the
valid flags in variable-range MTRRs and clear the E flag in the
IA32_MTRR_DEF_TYPE MSR to disable all MTRRs. All other bits in the
MTRRs are undefined.
We currently do none of that, so whatever MTRR settings you had prior
to reset is what you have after reset. Usually this doesn't matter
because KVM often ignores the guest mappings and uses write-back
anyway. However, if you have an assigned device and an IOMMU that
allows NoSnoop for that device, KVM defers to the guest memory
mappings which are now stale after reset. The result is that OVMF
rebooting on such a configuration takes a full minute to LZMA
decompress the firmware volume, a process that is nearly instant on
the initial boot.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
KVM_FEATURE_CLOCKSOURCE_STABLE_BIT is enabled by default and supported
by KVM. But not having a name defined makes QEMU treat it as an unknown
and unmigratable feature flag (as any unknown feature may possibly
require state to be migrated), and disable it by default on "-cpu host".
As a side-effect, the new name also makes the flag configurable,
allowing the user to disable it (which may be useful for testing or for
compatibility with old kernels).
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This adds a new CPU model named "Broadwell". It has all the features
from Haswell, plus PREFETCHW, RDSEED, ADX, SMAP.
PREFETCHW was already supported as "3dnowprefetch".
RDSEED, ADX was added on Linux v3.15-rc1.
SMAP was added on Linux v3.15-rc2.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Cc: Wang, Yong Y <yong.y.wang@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dugger, Donald D <donald.d.dugger@intel.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Expose "Invariant TSC" flag, if KVM is enabled. From Intel documentation:
17.13.1 Invariant TSC The time stamp counter in newer processors may
support an enhancement, referred to as invariant TSC. Processor’s
support for invariant TSC is indicated by CPUID.80000007H:EDX[8].
The invariant TSC will run at a constant rate in all ACPI P-, C-.
and T-states. This is the architectural behavior moving forward. On
processors with invariant TSC support, the OS may use the TSC for wall
clock timer services (instead of ACPI or HPET timers). TSC reads are
much more efficient and do not incur the overhead associated with a ring
transition or access to a platform resource.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
[ehabkost: redo feature filtering to use .tcg_features]
[ehabkost: add CPUID_APM_INVTSC macro, add it to .unmigratable_flags]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Having only migratable flags reported by default on the "host" CPU model
is safer for the following reasons:
* Existing users may expect "-cpu host" to be migration-safe, if they
take care of always using compatible host CPUs, host kernels, and
QEMU versions.
* Users who don't care aboug migration and want to enable all features
supported by the host kernel can simply change their setup to use
migratable=no.
Without this change, people using "-cpu host" will stop being able to
migrate, because now "invtsc" is getting enabled by default.
We are not setting migratable=yes by default on all X86CPU subclasses,
because users should be able to get non-migratable features enabled if
they ask for them explicitly.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
This flag will allow the user to choose between two modes:
* All flags that can be enabled on the host, even if unmigratable
(migratable=no);
* All flags that can be enabled on the host, are known to QEMU
and migratable (migratable=yes).
The default is still migratable=false, to keep current behavior, but
this will be changed to migratable=true by another patch.
My plan was to support the "migratable" flag on all CPU classes, but
have the default to "false" on all CPU models except "host". However,
DeviceClass has no mechanism to allow a child class to have a different
property default from the parent class yet, so by now only the "host"
CPU model will support the "migratable" flag.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
If enforce/check is specified in TCG mode, QEMU will ensure all CPU
features are supported by TCG, so no CPU feature is silently disabled.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
[AF: Be explicit about TCG vs. !KVM]
Signed-off-by: Andreas Färber <afaerber@suse.de>
Instead of manually filtering each feature word, add a tcg_features
field to FeatureWordInfo, and use that field to filter all feature words
in TCG mode.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Now that we have the feature word arrays, we don't need to manually copy
each array item, we can simply iterate through each feature word.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Those macros will be used in the feature_word_info array data, so need
to be defined earlier.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
TCG doesn't support any of the feature flags on FEAT_KVM and
FEAT_C000_0001_EDX feature words, so clear all bits on those feature
words.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
The TCG_7_0_EBX_FEATURES macro was defined but never used (it even had a
typo that was never noticed). Make the existing TCG feature filtering
code use it.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Andreas Färber <afaerber@suse.de>
Instead of an #ifdef in the middle of the code, just set
TCG_EXT2_FEATURES to a different value depending on TARGET_X86_64.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
This will allow us to re-use the feature filtering logic (and the
check/enforce flag logic) for TCG.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
This will help us simplify the code that calls
report_unavailable_features() later.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Merge filter_features_for_kvm() and kvm_check_features_against_host().
Both functions made exactly the same calculations, the only difference
was that filter_features_for_kvm() changed the bits on cpu->features[],
and kvm_check_features_against_host() did error reporting.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Instead of checking and calling unavailable_host_feature() once for each
bit, simply call the function (now renamed to
report_unavailable_features()) once for each feature word.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
[AF: Drop unused return value]
Signed-off-by: Andreas Färber <afaerber@suse.de>
KVM never supported the MONITOR flag so it doesn't make sense to have it
enabled by default when KVM is enabled.
The rationale here is similar to the cases where it makes sense to have
a feature enabled by default on all CPU models when on KVM mode (e.g.
x2apic). In this case we are having a feature disabled by default for
the same reasons.
In this case we don't need machine-type compat code because it is
currently impossible to run a KVM VM with the MONITOR flag set.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Because of the "goto out", the contents of local_err are leaked
and lost.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
* remotes/bonzini/softmmu-smap: (33 commits)
target-i386: cleanup x86_cpu_get_phys_page_debug
target-i386: fix protection bits in the TLB for SMEP
target-i386: support long addresses for 4MB pages (PSE-36)
target-i386: raise page fault for reserved bits in large pages
target-i386: unify reserved bits and NX bit check
target-i386: simplify pte/vaddr calculation
target-i386: raise page fault for reserved physical address bits
target-i386: test reserved PS bit on PML4Es
target-i386: set correct error code for reserved bit access
target-i386: introduce support for 1 GB pages
target-i386: introduce do_check_protect label
target-i386: tweak handling of PG_NX_MASK
target-i386: commonize checks for PAE and non-PAE
target-i386: commonize checks for 4MB and 4KB pages
target-i386: commonize checks for 2MB and 4KB pages
target-i386: fix coding standards in x86_cpu_handle_mmu_fault
target-i386: simplify SMAP handling in MMU_KSMAP_IDX
target-i386: fix kernel accesses with SMAP and CPL = 3
target-i386: move check_io helpers to seg_helper.c
target-i386: rename KSMAP to KNOSMAP
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
4MB pages can use 40-bit addresses by putting the higher 8 bits in bits
20-13 of the PDE. Bit 21 is reserved.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>