With this flag, kvm allows guest to control host CPU power state. This
increases latency for other processes using same host CPU in an
unpredictable way, but if decreases idle entry/exit times for the
running VCPU, so to use it QEMU needs a hint about whether host CPU is
overcommitted, hence the flag name.
Follow-up patches will expose this capability to guest
(using mwait leaf).
Based on a patch by Wanpeng Li <kernellwp@gmail.com> .
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20180622192148.178309-2-mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let's start to use "info pic" just like other platforms. For now we
keep the command for a while so that old users can know what is the new
command to use.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20171229073104.3810-6-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It calls cpu_loop_exit in system emulation mode (and should never be
called in user emulation mode).
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Message-Id: <6f4d44ffde55d074cbceb48309c1678600abad2f.1522769774.git.jan.kiszka@web.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We need to terminate the translation block after STGI so that pending
interrupts can be injected.
This fixes pending NMI injection for Jailhouse which uses "stgi; clgi"
to open a brief injection window.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Message-Id: <37939b244dda0e9cccf96ce50f2b15df1e48315d.1522769774.git.jan.kiszka@web.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Check for SVM interception prior to injecting an NMI. Tested via the
Jailhouse hypervisor.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Message-Id: <c65877e9a011ee4962931287e59f502c482b8d0b.1522769774.git.jan.kiszka@web.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some variations of Linux kernels end up accessing MSR's that the Windows
Hypervisor doesn't implement which causes a GP to be returned to the guest.
This fix registers QEMU for unimplemented MSR access and globally returns 0 on
reads and ignores writes. This behavior is allows the Linux kernel to probe the
MSR with a write/read/check sequence it does often without failing the access.
Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>
Message-Id: <20180605221500.21674-2-juterry@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Adds a workaround to an incorrect value setting
CPUID Fn8000_0001_ECX[bit 9 OSVW] = 1. This can cause a guest linux kernel
to panic when an issue to rdmsr C001_0140h returns 0. Disabling this feature
correctly allows the guest to boot without accessing the osv workarounds.
Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>
Message-Id: <20180605221500.21674-1-juterry@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The implementation of these two instructions was swapped.
At the same time, unify the setup of eflags for the insn group.
Reported-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170712192902.15493-1-rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remove generic non-intel check while validating hyperthreading support.
Certain AMD CPUs can support hyperthreading now.
CPU family with TOPOEXT feature can support hyperthreading now.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Tested-by: Geoffrey McRae <geoff@hostfission.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1529443919-67509-4-git-send-email-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Enable TOPOEXT feature on EPYC CPU. This is required to support
hyperthreading on VM guests. Also extend xlevel to 0x8000001E.
Disable topoext on PC_COMPAT_2_12 and keep xlevel 0x8000000a.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1529443919-67509-3-git-send-email-babu.moger@amd.com>
[ehabkost: Added EPYC-IBPB.xlevel to PC_COMPAT_2_12]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This is part of topoext support. To keep the compatibility, it is better
we support all the combination of nr_cores and nr_threads currently
supported. By allowing more nr_cores and nr_threads, we might end up with
more nodes than we can actually support with the real hardware. We need to
fix up the node id to make this work. We can achieve this by shifting the
socket_id bits left to address more nodes.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1529443919-67509-2-git-send-email-babu.moger@amd.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Enabling TOPOEXT feature might cause compatibility issues if
older kernels does not set this feature. Lets set this feature
unconditionally.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1528939107-17193-2-git-send-email-babu.moger@amd.com>
[ehabkost: rewrite comment and commit message]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
AMD future CPUs expose a mechanism to tell the guest that the
Speculative Store Bypass Disable is not needed and that the
CPU is all good.
This is exposed via the CPUID 8000_0008.EBX[26] bit.
See 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf
A copy of this document is available at
https://bugzilla.kernel.org/show_bug.cgi?id=199889
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Message-Id: <20180601153809.15259-3-konrad.wilk@oracle.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
AMD future CPUs expose _two_ ways to utilize the Intel equivalant
of the Speculative Store Bypass Disable. The first is via
the virtualized VIRT_SPEC CTRL MSR (0xC001_011f) and the second
is via the SPEC_CTRL MSR (0x48). The document titled:
124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf
gives priority of SPEC CTRL MSR over the VIRT SPEC CTRL MSR.
A copy of this document is available at
https://bugzilla.kernel.org/show_bug.cgi?id=199889
Anyhow, this means that on future AMD CPUs there will be _two_ ways to
deal with SSBD.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Message-Id: <20180601153809.15259-2-konrad.wilk@oracle.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
OSPKE is not a static feature flag: it changes dynamically at
runtime depending on CR4, and it was never configurable: KVM
never returned OSPKE on GET_SUPPORTED_CPUID, and on TCG enables
it automatically if CR4_PKE_MASK is set.
Remove OSPKE from the feature name array so users don't try to
configure it manually.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20180611203712.12086-1-ehabkost@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
OSXAVE is not a static feature flag: it changes dynamically at
runtime depending on CR4, and it was never configurable: KVM
never returned OSXSAVE on GET_SUPPORTED_CPUID, and it is not
included in TCG_EXT_FEATURES.
Remove OSXSAVE from the feature name array so users don't try to
configure it manually.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20180611203855.13269-1-ehabkost@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
When using '-cpu help' the list of CPUID features is grouped according
to the internal low level CPUID grouping. The data printed results in
very long lines too.
This combines to make it hard for users to read the output and identify
if QEMU knows about the feature they wish to use.
This change gets rid of the grouping of features and treats all flags as
single list. The list is sorted into alphabetical order and the printing
with line wrapping at the 77th column.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-4-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The current list of CPU model names output by "-cpu help" is sorted
alphabetically based on the internal QOM class name. The text that is
displayed, however, uses the CPU model name, which is equivalent to the
QOM class name, minus a suffix. Unfortunately that suffix has an effect
on the sort ordering, for example, causing the various Broadwell
variants to appear reversed:
x86 486
x86 Broadwell-IBRS Intel Core Processor (Broadwell, IBRS)
x86 Broadwell-noTSX-IBRS Intel Core Processor (Broadwell, no TSX, IBRS
x86 Broadwell-noTSX Intel Core Processor (Broadwell, no TSX)
x86 Broadwell Intel Core Processor (Broadwell)
x86 Conroe Intel Celeron_4x0 (Conroe/Merom Class Core 2)
By sorting on the actual CPU model name text that is displayed, the
result is
x86 486
x86 Broadwell Intel Core Processor (Broadwell)
x86 Broadwell-IBRS Intel Core Processor (Broadwell, IBRS)
x86 Broadwell-noTSX Intel Core Processor (Broadwell, no TSX)
x86 Broadwell-noTSX-IBRS Intel Core Processor (Broadwell, no TSX, IBRS)
x86 Conroe Intel Celeron_4x0 (Conroe/Merom Class Core 2)
This requires extra string allocations during sorting, but this is not a
concern given the usage scenario and the number of CPU models that exist.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-3-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Since the addition of the -IBRS CPU model variants, the descriptions
shown by '-cpu help' are not well aligned, as several model names
overflow the space allowed. Right aligning the CPU model names is also
not attractive, because it obscures the common name prefixes of many
models. The CPU model name field needs to be 4 characters larger, and
be left aligned instead.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-2-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Add support for cpuid leaf CPUID_8000_001E. Build the config that closely
match the underlying hardware. Please refer to the Processor Programming
Reference (PPR) for AMD Family 17h Model for more details.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1528498581-131037-2-git-send-email-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Add information for cpuid 0x8000001D leaf. Populate cache topology information
for different cache types (Data Cache, Instruction Cache, L2 and L3) supported
by 0x8000001D leaf. Please refer to the Processor Programming Reference (PPR)
for AMD Family 17h Model for more details.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1527176614-26271-3-git-send-email-babu.moger@amd.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Always initialize CPUCaches structs with cache information, even
if legacy_cache=true. Use different CPUCaches struct for
CPUID[2], CPUID[4], and the AMD CPUID leaves.
This will simplify a lot the logic inside cpu_x86_cpuid().
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1527176614-26271-2-git-send-email-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Do the cast to uintptr_t within the helper, so that the compiler
can type check the pointer argument. We can also do some more
sanity checking of the index argument.
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Now we've updated our copy of the kernel headers we can remove the
compatibility shim that handled KVM_HINTS_REALTIME not being defined.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180525132755.21839-7-peter.maydell@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In kernel header commit 633711e8287, the define KVM_HINTS_DEDICATED
was renamed to KVM_HINTS_REALTIME. Work around this compatibility
break by (a) using the new constant name, and (b) defining it
if the headers don't.
Part (b) can be removed once we've updated our copy of the kernel
headers to a version that defines KVM_HINTS_REALTIME.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180525132755.21839-5-peter.maydell@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch fixes a few compiler warnings, especially in case of
x86 targets, where the number of registers was not properly handled
and could cause an overflow.
Signed-off-by: Alessandro Pilotti <apilotti@cloudbasesolutions.com>
Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>
Signed-off-by: Lucian Petrut <lpetrut@cloudbasesolutions.com>
Message-Id: <1526405722-10887-3-git-send-email-lpetrut@cloudbasesolutions.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We're currently linking against import libraries of the WHP DLLs.
By dynamically loading the libraries, we ensure that QEMU will work
on previous Windows versions, where the WHP DLLs will be missing
(assuming that WHP is not requested).
Also, we're simplifying the build process, as we no longer require
the import libraries.
Signed-off-by: Alessandro Pilotti <apilotti@cloudbasesolutions.com>
Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>
Signed-off-by: Lucian Petrut <lpetrut@cloudbasesolutions.com>
Message-Id: <1526405722-10887-2-git-send-email-lpetrut@cloudbasesolutions.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Switch to the header we imported from Linux,
this allows us to drop a hack in kvm_i386.h.
More code will be dropped in the next patch.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
AMD Zen expose the Intel equivalant to Speculative Store Bypass Disable
via the 0x80000008_EBX[25] CPUID feature bit.
This needs to be exposed to guest OS to allow them to protect
against CVE-2018-3639.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180521215424.13520-3-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
"Some AMD processors only support a non-architectural means of enabling
speculative store bypass disable (SSBD). To allow a simplified view of
this to a guest, an architectural definition has been created through a new
CPUID bit, 0x80000008_EBX[25], and a new MSR, 0xc001011f. With this, a
hypervisor can virtualize the existence of this definition and provide an
architectural method for using SSBD to a guest.
Add the new CPUID feature, the new MSR and update the existing SSBD
support to use this MSR when present." (from x86/speculation: Add virtualized
speculative store bypass disable support in Linux).
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180521215424.13520-4-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
New microcode introduces the "Speculative Store Bypass Disable"
CPUID feature bit. This needs to be exposed to guest OS to allow
them to protect against CVE-2018-3639.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Message-Id: <20180521215424.13520-2-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The property legacy-cache will be used to control the cache information.
If user passes "-cpu legacy-cache" then older information will
be displayed even if the hardware supports new information. Otherwise
use the statically loaded cache definitions if available.
Renamed the previous cache structures to legacy_*. If there is any change in
the cache information, then it needs to be initialized in builtin_x86_defs.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Tested-by: Geoffrey McRae <geoff@hostfission.com>
Message-Id: <20180514164156.27034-3-babu.moger@amd.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Instead of having a collection of macros that need to be used in
complex expressions to build CPUID data, define a CPUCacheInfo
struct that can hold information about a given cache. Helper
functions will take a CPUCacheInfo struct as input to encode
CPUID leaves for a cache.
This will help us ensure consistency between cache information
CPUID leaves, and make the existing inconsistencies in CPUID info
more visible.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Tested-by: Geoffrey McRae <geoff@hostfission.com>
Message-Id: <20180510204148.11687-2-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The CLDEMOTE instruction hints to hardware that the cache line that
contains the linear address should be moved("demoted") from
the cache(s) closest to the processor core to a level more distant
from the processor core. This may accelerate subsequent accesses
to the line by other cores in the same coherence domain,
especially if the line was written by the core that demotes the line.
Intel Snow Ridge has added new cpu feature, CLDEMOTE.
The new cpu feature needs to be exposed to guest VM.
The bit definition:
CPUID.(EAX=7,ECX=0):ECX[bit 25] CLDEMOTE
The release document ref below link:
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Signed-off-by: Jingqi Liu <jingqi.liu@intel.com>
Message-Id: <1525406253-54846-1-git-send-email-jingqi.liu@intel.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
A new cpu model called "KnightsMill" is added to model Knights Mill
processors. Compared to "Skylake-Server" cpu model, the following
features are added:
avx512_4vnniw avx512_4fmaps avx512pf avx512er avx512_vpopcntdq
and the following features are removed:
pcid invpcid clflushopt avx512dq avx512bw clwb smap rtm mpx
xsavec xgetbv1 hle
Signed-off-by: Boqun Feng <boqun.feng@intel.com>
Message-Id: <20180320000821.8337-1-boqun.feng@intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
* dtc configure fixes
* MemoryRegionCache second try
* Deprecated option removal
* add support for Hyper-V reenlightenment MSRs
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
* Don't silently truncate extremely long words in the command line
* dtc configure fixes
* MemoryRegionCache second try
* Deprecated option removal
* add support for Hyper-V reenlightenment MSRs
# gpg: Signature made Fri 11 May 2018 13:33:46 BST
# gpg: using RSA key BFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1
# Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83
* remotes/bonzini/tags/for-upstream: (29 commits)
rename included C files to foo.inc.c, remove osdep.h
pc-dimm: fix error messages if no slots were defined
build: Silence dtc directory creation
shippable: Remove Debian 8 libfdt kludge
configure: Display if libfdt is from system or git
configure: Really use local libfdt if the system one is too old
i386/kvm: add support for Hyper-V reenlightenment MSRs
qemu-doc: provide details of supported build platforms
qemu-options: Remove deprecated -no-kvm-irqchip
qemu-options: Remove deprecated -no-kvm-pit-reinjection
qemu-options: Bail out on unsupported options instead of silently ignoring them
qemu-options: Remove remainders of the -tdf option
qemu-options: Mark -virtioconsole as deprecated
target/i386: sev: fix memory leaks
opts: don't silently truncate long option values
opts: don't silently truncate long parameter keys
accel: use g_strsplit for parsing accelerator names
update-linux-headers: drop hyperv.h
qemu-thread: always keep the posix wrapper layer
exec: reintroduce MemoryRegion caching
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
KVM recently gained support for Hyper-V Reenlightenment MSRs which are
required to make KVM-on-Hyper-V enable TSC page clocksource to its guests
when INVTSC is not passed to it (and it is not passed by default in Qemu
as it effectively blocks migration).
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20180411115036.31832-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While at it, use int for both num_insns and max_insns to make
sure we have same-type comparisons.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The assumption in the cpu->max_features code is that anything
enabled on GET_SUPPORTED_CPUID should be enabled on "-cpu host".
This shouldn't be the case for FEAT_KVM_HINTS.
This adds a new FeatureWordInfo::no_autoenable_flags field, that
can be used to prevent FEAT_KVM_HINTS bits to be enabled
automatically.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20180410211534.26079-1-ehabkost@redhat.com>
Tested-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
In icount mode, instructions that access io memory spaces in the middle
of the translation block invoke TB recompilation. After recompilation,
such instructions become last in the TB and are allowed to access io
memory spaces.
When the code includes instruction like i386 'xchg eax, 0xffffd080'
which accesses APIC, QEMU goes into an infinite loop of the recompilation.
This instruction includes two memory accesses - one read and one write.
After the first access, APIC calls cpu_report_tpr_access, which restores
the CPU state to get the current eip. But cpu_restore_state_from_tb
resets the cpu->can_do_io flag which makes the second memory access invalid.
Therefore the second memory access causes a recompilation of the block.
Then these operations repeat again and again.
This patch moves resetting cpu->can_do_io flag from
cpu_restore_state_from_tb to cpu_loop_exit* functions.
It also adds a parameter for cpu_restore_state which controls restoring
icount. There is no need to restore icount when we only query CPU state
without breaking the TB. Restoring it in such cases leads to the
incorrect flow of the virtual time.
In most cases new parameter is true (icount should be recalculated).
But there are two cases in i386 and openrisc when the CPU state is only
queried without the need to break the TB. This patch fixes both of
these cases.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Message-Id: <20180409091320.12504.35329.stgit@pasha-VirtualBox>
[rth: Make can_do_io setting unconditional; move from cpu_exec;
make cpu_loop_exit_{noexc,restore} call cpu_loop_exit.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
