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path: root/arch/x86/kvm/x86.c
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2012-03-14x86-kvm-require-const-tsc-for-rt.patchThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-12-26KVM: Don't automatically expose the TSC deadline timer in cpuidJan Kiszka
Unlike all of the other cpuid bits, the TSC deadline timer bit is set unconditionally, regardless of what userspace wants. This is broken in several ways: - if userspace doesn't use KVM_CREATE_IRQCHIP, and doesn't emulate the TSC deadline timer feature, a guest that uses the feature will break - live migration to older host kernels that don't support the TSC deadline timer will cause the feature to be pulled from under the guest's feet; breaking it - guests that are broken wrt the feature will fail. Fix by not enabling the feature automatically; instead report it to userspace. Because the feature depends on KVM_CREATE_IRQCHIP, which we cannot guarantee will be called, we expose it via a KVM_CAP_TSC_DEADLINE_TIMER and not KVM_GET_SUPPORTED_CPUID. Fixes the Illumos guest kernel, which uses the TSC deadline timer feature. [avi: add the KVM_CAP + documentation] Reported-by: Alexey Zaytsev <alexey.zaytsev@gmail.com> Tested-by: Alexey Zaytsev <alexey.zaytsev@gmail.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-10-30Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommuLinus Torvalds
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (33 commits) iommu/core: Remove global iommu_ops and register_iommu iommu/msm: Use bus_set_iommu instead of register_iommu iommu/omap: Use bus_set_iommu instead of register_iommu iommu/vt-d: Use bus_set_iommu instead of register_iommu iommu/amd: Use bus_set_iommu instead of register_iommu iommu/core: Use bus->iommu_ops in the iommu-api iommu/core: Convert iommu_found to iommu_present iommu/core: Add bus_type parameter to iommu_domain_alloc Driver core: Add iommu_ops to bus_type iommu/core: Define iommu_ops and register_iommu only with CONFIG_IOMMU_API iommu/amd: Fix wrong shift direction iommu/omap: always provide iommu debug code iommu/core: let drivers know if an iommu fault handler isn't installed iommu/core: export iommu_set_fault_handler() iommu/omap: Fix build error with !IOMMU_SUPPORT iommu/omap: Migrate to the generic fault report mechanism iommu/core: Add fault reporting mechanism iommu/core: Use PAGE_SIZE instead of hard-coded value iommu/core: use the existing IS_ALIGNED macro iommu/msm: ->unmap() should return order of unmapped page ... Fixup trivial conflicts in drivers/iommu/Makefile: "move omap iommu to dedicated iommu folder" vs "Rename the DMAR and INTR_REMAP config options" just happened to touch lines next to each other.
2011-10-21iommu/core: Convert iommu_found to iommu_presentJoerg Roedel
With per-bus iommu_ops the iommu_found function needs to work on a bus_type too. This patch adds a bus_type parameter to that function and converts all call-places. The function is also renamed to iommu_present because the function now checks if an iommu is present for a given bus and does not check for a global iommu anymore. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-10-05KVM: emulate lapic tsc deadline timer for guestLiu, Jinsong
This patch emulate lapic tsc deadline timer for guest: Enumerate tsc deadline timer capability by CPUID; Enable tsc deadline timer mode by lapic MMIO; Start tsc deadline timer by WRMSR; [jan: use do_div()] [avi: fix for !irqchip_in_kernel()] [marcelo: another fix for !irqchip_in_kernel()] Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: Fix simultaneous NMIsAvi Kivity
If simultaneous NMIs happen, we're supposed to queue the second and next (collapsing them), but currently we sometimes collapse the second into the first. Fix by using a counter for pending NMIs instead of a bool; since the counter limit depends on whether the processor is currently in an NMI handler, which can only be checked in vcpu context (via the NMI mask), we add a new KVM_REQ_NMI to request recalculation of the counter. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-09-25KVM: L1 TSC handlingNadav Har'El
KVM assumed in several places that reading the TSC MSR returns the value for L1. This is incorrect, because when L2 is running, the correct TSC read exit emulation is to return L2's value. We therefore add a new x86_ops function, read_l1_tsc, to use in places that specifically need to read the L1 TSC, NOT the TSC of the current level of guest. Note that one change, of one line in kvm_arch_vcpu_load, is made redundant by a different patch sent by Zachary Amsden (and not yet applied): kvm_arch_vcpu_load() should not read the guest TSC, and if it didn't, of course we didn't have to change the call of kvm_get_msr() to read_l1_tsc(). [avi: moved callback to kvm_x86_ops tsc block] Signed-off-by: Nadav Har'El <nyh@il.ibm.com> Acked-by: Zachary Amsdem <zamsden@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: x86: report valid microcode update IDMarcelo Tosatti
Windows Server 2008 SP2 checked build with smp > 1 BSOD's during boot due to lack of microcode update: *** Assertion failed: The system BIOS on this machine does not properly support the processor. The system BIOS did not load any microcode update. A BIOS containing the latest microcode update is needed for system reliability. (CurrentUpdateRevision != 0) *** Source File: d:\longhorn\base\hals\update\intelupd\update.c, line 440 Report a non-zero microcode update signature to make it happy. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: x86 emulator: Make x86_decode_insn() return proper macrosTakuya Yoshikawa
Return EMULATION_OK/FAILED consistently. Also treat instruction fetch errors, not restricted to X86EMUL_UNHANDLEABLE, as EMULATION_FAILED; although this cannot happen in practice, the current logic will continue the emulation even if the decoder fails to fetch the instruction. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: Intelligent device lookup on I/O busSasha Levin
Currently the method of dealing with an IO operation on a bus (PIO/MMIO) is to call the read or write callback for each device registered on the bus until we find a device which handles it. Since the number of devices on a bus can be significant due to ioeventfds and coalesced MMIO zones, this leads to a lot of overhead on each IO operation. Instead of registering devices, we now register ranges which points to a device. Lookup is done using an efficient bsearch instead of a linear search. Performance test was conducted by comparing exit count per second with 200 ioeventfds created on one byte and the guest is trying to access a different byte continuously (triggering usermode exits). Before the patch the guest has achieved 259k exits per second, after the patch the guest does 274k exits per second. Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: Really fix HV_X64_MSR_APIC_ASSIST_PAGEMike Waychison
Commit 0945d4b228 tried to fix the get_msr path for the HV_X64_MSR_APIC_ASSIST_PAGE msr, but was poorly tested. We should be returning 0 if the read succeeded, and passing the value back to the caller via the pdata out argument, not returning the value directly. Signed-off-by: Mike Waychison <mikew@google.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: x86: get_msr support for HV_X64_MSR_APIC_ASSIST_PAGEMike Waychison
"get" support for the HV_X64_MSR_APIC_ASSIST_PAGE msr was missing, even though it is explicitly enumerated as something the vmm should save in msrs_to_save and reported to userland via the KVM_GET_MSR_INDEX_LIST ioctl. Add "get" support for HV_X64_MSR_APIC_ASSIST_PAGE. We simply return the guest visible value of this register, which seems to be correct as a set on the register is validated for us already. Signed-off-by: Mike Waychison <mikew@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-09-25KVM: x86: Raise the hard VCPU count limitSasha Levin
The patch raises the hard limit of VCPU count to 254. This will allow developers to easily work on scalability and will allow users to test high VCPU setups easily without patching the kernel. To prevent possible issues with current setups, KVM_CAP_NR_VCPUS now returns the recommended VCPU limit (which is still 64) - this should be a safe value for everybody, while a new KVM_CAP_MAX_VCPUS returns the hard limit which is now 254. Cc: Avi Kivity <avi@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Suggested-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-09-25KVM: x86: cleanup the code of read/write emulationXiao Guangrong
Using the read/write operation to remove the same code Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: x86: abstract the operation for read/write emulationXiao Guangrong
The operations of read emulation and write emulation are very similar, so we can abstract the operation of them, in larter patch, it is used to cleanup the same code Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25KVM: x86: fix broken read emulation spans a page boundaryXiao Guangrong
If the range spans a page boundary, the mmio access can be broke, fix it as write emulation. And we already get the guest physical address, so use it to read guest data directly to avoid walking guest page table again Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-24KVM: MMU: trace mmio page faultXiao Guangrong
Add tracepoints to trace mmio page fault Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-24KVM: MMU: mmio page fault supportXiao Guangrong
The idea is from Avi: | We could cache the result of a miss in an spte by using a reserved bit, and | checking the page fault error code (or seeing if we get an ept violation or | ept misconfiguration), so if we get repeated mmio on a page, we don't need to | search the slot list/tree. | (https://lkml.org/lkml/2011/2/22/221) When the page fault is caused by mmio, we cache the info in the shadow page table, and also set the reserved bits in the shadow page table, so if the mmio is caused again, we can quickly identify it and emulate it directly Searching mmio gfn in memslots is heavy since we need to walk all memeslots, it can be reduced by this feature, and also avoid walking guest page table for soft mmu. [jan: fix operator precedence issue] Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-24KVM: MMU: remove bypass_guest_pfXiao Guangrong
The idea is from Avi: | Maybe it's time to kill off bypass_guest_pf=1. It's not as effective as | it used to be, since unsync pages always use shadow_trap_nonpresent_pte, | and since we convert between the two nonpresent_ptes during sync and unsync. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-24KVM: MMU: cache mmio info on page fault pathXiao Guangrong
If the page fault is caused by mmio, we can cache the mmio info, later, we do not need to walk guest page table and quickly know it is a mmio fault while we emulate the mmio instruction Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-24KVM: x86: introduce vcpu_mmio_gva_to_gpa to cleanup the codeXiao Guangrong
Introduce vcpu_mmio_gva_to_gpa to translate the gva to gpa, we can use it to cleanup the code between read emulation and write emulation Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-14KVM: Steal time implementationGlauber Costa
To implement steal time, we need the hypervisor to pass the guest information about how much time was spent running other processes outside the VM, while the vcpu had meaningful work to do - halt time does not count. This information is acquired through the run_delay field of delayacct/schedstats infrastructure, that counts time spent in a runqueue but not running. Steal time is a per-cpu information, so the traditional MSR-based infrastructure is used. A new msr, KVM_MSR_STEAL_TIME, holds the memory area address containing information about steal time This patch contains the hypervisor part of the steal time infrasructure, and can be backported independently of the guest portion. [avi, yongjie: export delayacct_on, to avoid build failures in some configs] Signed-off-by: Glauber Costa <glommer@redhat.com> Tested-by: Eric B Munson <emunson@mgebm.net> CC: Rik van Riel <riel@redhat.com> CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> CC: Peter Zijlstra <peterz@infradead.org> CC: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Yongjie Ren <yongjie.ren@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Enable ERMS feature support for KVMYang, Wei
This patch exposes ERMS feature to KVM guests. The REP MOVSB/STOSB instruction can enhance fast strings attempts to move as much of the data with larger size load/stores as possible. Signed-off-by: Yang, Wei <wei.y.yang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Expose RDWRGSFS bit to KVM guestsYang, Wei
This patch exposes RDWRGSFS bit to KVM guests. Signed-off-by: Yang, Wei <wei.y.yang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Add RDWRGSFS support when setting CR4Yang, Wei
This patch adds RDWRGSFS support when setting CR4. Signed-off-by: Yang, Wei <wei.y.yang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Enable DRNG feature support for KVMYang, Wei Y
This patch exposes DRNG feature to KVM guests. The RDRAND instruction can provide software with sequences of random numbers generated from white noise. Signed-off-by: Yang, Wei <wei.y.yang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: fix XSAVE bit scanning (now properly)Andre Przywara
commit 123108f1c1aafd51d6a5c79cc04d7999dd88a930 tried to fix KVMs XSAVE valid feature scanning, but it was wrong. It was not considering the sparse nature of this bitfield, instead reading values from uninitialized members of the entries array. This patch now separates subleaf indicies from KVM's array indicies and fills the entry before querying it's value. This fixes AVX support in KVM guests. Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Mask function7 ebx against host capability word9Yang, Wei Y
This patch masks CPUID leaf 7 ebx against host capability word9. Signed-off-by: Yang, Wei <wei.y.yang@intel.com> Signed-off-by: Shan, Haitao <haitao.shan@intel.com> Signed-off-by: Li, Xin <xin.li@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Add SMEP support when setting CR4Yang, Wei Y
This patch adds SMEP handling when setting CR4. Signed-off-by: Yang, Wei <wei.y.yang@intel.com> Signed-off-by: Shan, Haitao <haitao.shan@intel.com> Signed-off-by: Li, Xin <xin.li@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: x86 emulator: fold decode_cache into x86_emulate_ctxtAvi Kivity
This saves a lot of pointless casts x86_emulate_ctxt and decode_cache. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: x86 emulator: rename decode_cache::eip to _eipAvi Kivity
The name eip conflicts with a field of the same name in x86_emulate_ctxt, which we plan to fold decode_cache into. The name _eip is unfortunate, but what's really needed is a refactoring here, not a better name. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: x86 emulator: Use the pointers ctxt and c consistentlyTakuya Yoshikawa
We should use the local variables ctxt and c when the emulate_ctxt and decode appears many times. At least, we need to be consistent about how we use these in a function. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: nVMX: Implement VMPTRSTNadav Har'El
This patch implements the VMPTRST instruction. Signed-off-by: Nadav Har'El <nyh@il.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: nVMX: Implement VMCLEARNadav Har'El
This patch implements the VMCLEAR instruction. Signed-off-by: Nadav Har'El <nyh@il.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: nVMX: Decoding memory operands of VMX instructionsNadav Har'El
This patch includes a utility function for decoding pointer operands of VMX instructions issued by L1 (a guest hypervisor) Signed-off-by: Nadav Har'El <nyh@il.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: nVMX: Allow setting the VMXE bit in CR4Nadav Har'El
This patch allows the guest to enable the VMXE bit in CR4, which is a prerequisite to running VMXON. Whether to allow setting the VMXE bit now depends on the architecture (svm or vmx), so its checking has moved to kvm_x86_ops->set_cr4(). This function now returns an int: If kvm_x86_ops->set_cr4() returns 1, __kvm_set_cr4() will also return 1, and this will cause kvm_set_cr4() will throw a #GP. Turning on the VMXE bit is allowed only when the nested VMX feature is enabled, and turning it off is forbidden after a vmxon. Signed-off-by: Nadav Har'El <nyh@il.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: x86 emulator: Avoid clearing the whole decode_cacheTakuya Yoshikawa
During tracing the emulator, we noticed that init_emulate_ctxt() sometimes took a bit longer time than we expected. This patch is for mitigating the problem by some degree. By looking into the function, we soon notice that it clears the whole decode_cache whose size is about 2.5K bytes now. Furthermore, most of the bytes are taken for the two read_cache arrays, which are used only by a few instructions. Considering the fact that we are not assuming the cache arrays have been cleared when we store actual data, we do not need to clear the arrays: 2K bytes elimination. In addition, we can avoid clearing the fetch_cache and regs arrays. This patch changes the initialization not to clear the arrays. On our 64-bit host, init_emulate_ctxt() becomes 0.3 to 0.5us faster with this patch applied. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: x86 emulator: Clean up init_emulate_ctxt()Takuya Yoshikawa
Use a local pointer to the emulate_ctxt for simplicity. Then, arrange the hard-to-read mode selection lines neatly. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Clean up error handling during VCPU creationJan Kiszka
So far kvm_arch_vcpu_setup is responsible for freeing the vcpu struct if it fails. Move this confusing resonsibility back into the hands of kvm_vm_ioctl_create_vcpu. Only kvm_arch_vcpu_setup of x86 is affected, all other archs cannot fail. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12KVM: Sanitize cpuidAvi Kivity
Instead of blacklisting known-unsupported cpuid leaves, whitelist known- supported leaves. This is more conservative and prevents us from reporting features we don't support. Also whitelist a few more leaves while at it. Signed-off-by: Avi Kivity <avi@redhat.com> Acked-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: use __copy_to_user/__clear_user to write guest pageXiao Guangrong
Simply use __copy_to_user/__clear_user to write guest page since we have already verified the user address when the memslot is set Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-07-12KVM: x86 emulator: Stop passing ctxt->ops as arg of emul functionsTakuya Yoshikawa
Dereference it in the actual users. This not only cleans up the emulator but also makes it easy to convert the old emulation functions to the new em_xxx() form later. Note: Remove some inline keywords to let the compiler decide inlining. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-05-22KVM: x86 emulator: consolidate segment accessorsAvi Kivity
Instead of separate accessors for the segment selector and cached descriptor, use one accessor for both. This simplifies the code somewhat. Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: Add CPUID support for VIA CPUBrillyWu@viatech.com.cn
The CPUIDs for Centaur are added, and then the features of PadLock hardware engine on VIA CPU, such as "ace", "ace_en" and so on, can be passed into the kvm guest. Signed-off-by: Brilly Wu <brillywu@viatech.com.cn> Signed-off-by: Kary Jin <karyjin@viatech.com.cn> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: call cache_all_regs() only once during instruction emulationGleb Natapov
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: Fix compound mmioGleb Natapov
mmio_index should be taken into account when copying data from userspace. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: mmio_fault_cr2 is not usedGleb Natapov
Remove unused variable mmio_fault_cr2. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: x86 emulator: drop x86_emulate_ctxt::vcpuAvi Kivity
No longer used. Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: Avoid using x86_emulate_ctxt.vcpuAvi Kivity
We can use container_of() instead. Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-22KVM: x86 emulator: add new ->wbinvd() callbackAvi Kivity
Instead of calling kvm_emulate_wbinvd() directly. Signed-off-by: Avi Kivity <avi@redhat.com>