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path: root/arch/mips/kvm/trap_emul.c
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2017-06-04KVM: add kvm_request_pendingRadim Krčmář
A first step in vcpu->requests encapsulation. Additionally, we now use READ_ONCE() when accessing vcpu->requests, which ensures we always load vcpu->requests when it's accessed. This is important as other threads can change it any time. Also, READ_ONCE() documents that vcpu->requests is used with other threads, likely requiring memory barriers, which it does. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> [ Documented the new use of READ_ONCE() and converted another check in arch/mips/kvm/vz.c ] Signed-off-by: Andrew Jones <drjones@redhat.com> Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-03-28KVM: MIPS/T&E: Report correct dcache line sizeJames Hogan
Octeon CPUs don't report the correct dcache line size in CP0_Config1.DL, so encode the correct value for the guest CP0_Config1.DL based on cpu_dcache_line_size(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Daney <david.daney@cavium.com> Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-03-28KVM: MIPS: Abstract guest CP0 register access for VZJames Hogan
Abstract the MIPS KVM guest CP0 register access macros into inline functions which are generated by macros. This allows them to be generated differently for VZ, where they will usually need to access the hardware guest CP0 context rather than the saved values in RAM. Accessors for each individual register are generated using these macros: - __BUILD_KVM_*_SW() for registers which are not present in the VZ hardware guest context, so kvm_{read,write}_c0_guest_##name() will access the saved value in RAM regardless of whether VZ is enabled. - __BUILD_KVM_*_HW() for registers which are present in the VZ hardware guest context, so kvm_{read,write}_c0_guest_##name() will access the hardware register when VZ is enabled. These build the underlying accessors using further macros: - __BUILD_KVM_*_SAVED() builds e.g. kvm_{read,write}_sw_gc0_##name() functions for accessing the saved versions of the registers in RAM. This is used for implementing the common kvm_{read,write}_c0_guest_##name() accessors with T&E where registers are always stored in RAM, but are also available with VZ HW registers to allow them to be accessed while saved. - __BUILD_KVM_*_VZ() builds e.g. kvm_{read,write}_vz_gc0_##name() functions for accessing the VZ hardware guest context registers directly. This is used for implementing the common kvm_{read,write}_c0_guest_##name() accessors with VZ. - __BUILD_KVM_*_WRAP() builds wrappers with different names, which allows the common kvm_{read,write}_c0_guest_##name() functions to be implemented using the VZ accessors while still having the SAVED accessors available too. - __BUILD_KVM_SAVE_VZ() builds functions for saving and restoring VZ hardware guest context register state to RAM, improving conciseness of VZ context saving and restoring. Similar macros exist for generating modifiers (set, clear, change), either with a normal unlocked read/modify/write, or using atomic LL/SC sequences. These changes change the types of 32-bit registers to u32 instead of unsigned long, which requires some changes to printk() functions in MIPS KVM. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-03-28KVM: MIPS: Add guest exit exception callbackJames Hogan
Add a callback for MIPS KVM implementations to handle the VZ guest exit exception. Currently the trap & emulate implementation contains a stub which reports an internal error, but the callback will be used properly by the VZ implementation. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-03-28KVM: MIPS: Add hardware_{enable,disable} callbackJames Hogan
Add an implementation callback for the kvm_arch_hardware_enable() and kvm_arch_hardware_disable() architecture functions, with simple stubs for trap & emulate. This is in preparation for VZ which will make use of them. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-03-28KVM: MIPS: Add callback to check extensionJames Hogan
Add an implementation callback for checking presence of KVM extensions. This allows implementation specific extensions to be provided without ifdefs in mips.c. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-03-28KVM: MIPS: Init timer frequency from callbackJames Hogan
Currently the software emulated timer is initialised to a frequency of 100MHz by kvm_mips_init_count(), but this isn't suitable for VZ where the frequency of the guest timer matches that of the host. Add a count_hz argument so the caller can specify the default frequency, and move the call from kvm_arch_vcpu_create() to the implementation specific vcpu_setup() callback, so that VZ can specify a different frequency. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-03-28KVM: MIPS: Implement HYPCALL emulationJames Hogan
Emulate the HYPCALL instruction added in the VZ ASE and used by the MIPS paravirtualised guest support that is already merged. The new hypcall.c handles arguments and the return value. No actual hypercalls are yet supported, but this still allows us to safely step over hypercalls and set an error code in the return value for forward compatibility. Non-zero HYPCALL codes are not handled. We also document the hypercall ABI which asm/kvm_para.h uses. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com> Cc: David Daney <david.daney@cavium.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: linux-doc@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Expose read-only CP0_IntCtl registerJames Hogan
Expose the CP0_IntCtl register through the KVM register access API, which is a required register since MIPS32r2. It is currently read-only since the VS field isn't implemented due to lack of Config3.VInt or Config3.VEIC. It is implemented in trap_emul.c so that a VZ implementation can allow writes. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Expose CP0_EntryLo0/1 registersJames Hogan
Expose the CP0_EntryLo0 and CP0_EntryLo1 registers through the KVM register access API. This is fairly straightforward for trap & emulate since we don't support the RI and XI bits. For the sake of future proofing (particularly for VZ) it is explicitly specified that the API always exposes the 64-bit version of these registers (i.e. with the RI and XI bits in bit positions 63 and 62 respectively), and they are implemented in trap_emul.c rather than mips.c to allow them to be implemented differently for VZ. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Default to reset vectorJames Hogan
Set the default VCPU state closer to the architectural reset state, with PC pointing at the reset vector (uncached PA 0x1fc00000, which for KVM T&E is VA 0x5fc00000), and with CP0_Status.BEV and CP0_Status.ERL to 1. Although QEMU at least will overwrite this state, it makes sense to do this now that CP0_EBase is properly implemented to check BEV, and now that we support a sparse GPA layout potentially with a boot ROM at GPA 0x1fc00000. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Implement CP0_EBase registerJames Hogan
The CP0_EBase register is a standard feature of MIPS32r2, so we should always have been implementing it properly. However the register value was ignored and wasn't exposed to userland. Fix the emulation of exceptions and interrupts to use the value stored in guest CP0_EBase, and fix the masks so that the top 3 bits (rather than the standard 2) are fixed, so that it is always in the guest KSeg0 segment. Also add CP0_EBASE to the KVM one_reg interface so it can be accessed by userland, also allowing the CPU number field to be written (which isn't permitted by the guest). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Move CP0 register access into T&EJames Hogan
Access to various CP0 registers via the KVM register access API needs to be implementation specific to allow restrictions to be made on changes, for example when VZ guest registers aren't present, so move them all into trap_emul.c in preparation for VZ. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Handle read only GPA in TLB modJames Hogan
Rewrite TLB modified exception handling to handle read only GPA memory regions, instead of unconditionally passing the exception to the guest. If the guest TLB is not the cause of the exception we call into the normal TLB fault handling depending on the memory segment, which will soon attempt to remap the physical page to be writable (handling dirty page tracking or copy on write in the process). Failing that we fall back to treating it as MMIO, due to a read only memory region. Once the capability is enabled, this will allow read only memory regions (such as the Malta boot flash as emulated by QEMU) to have writes treated as MMIO, while still allowing reads to run untrapped. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Treat unhandled guest KSeg0 as MMIOJames Hogan
Treat unhandled accesses to guest KSeg0 as MMIO, rather than only host KSeg0 addresses. This will allow read only memory regions (such as the Malta boot flash as emulated by QEMU) to have writes (before reads) treated as MMIO, and unallocated physical addresses to have all accesses treated as MMIO. The MMIO emulation uses the gva_to_gpa callback, so this is also updated for trap & emulate to handle guest KSeg0 addresses. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Abstract bad access handlingJames Hogan
Abstract the handling of bad guest loads and stores which may need to trigger an MMIO, so that the same code can be used in a later patch for guest KSeg0 addresses (TLB exception handling) as well as for host KSeg1 addresses (existing address error exception and TLB exception handling). We now use kvm_mips_emulate_store() and kvm_mips_emulate_load() directly rather than the more generic kvm_mips_emulate_inst(), as there is no need to expose emulation of any other instructions. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Pass type of fault down to kvm_mips_map_page()James Hogan
kvm_mips_map_page() will need to know whether the fault was due to a read or a write in order to support dirty page tracking, KVM_CAP_SYNC_MMU, and read only memory regions, so get that information passed down to it via new bool write_fault arguments to various functions. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Ignore user writes to CP0_Config7James Hogan
Ignore userland writes to CP0_Config7 rather than reporting an error, since we do allow reads of this register and it is claimed to exist in the ioctl API. This allows userland to blindly save and restore KVM registers without having to special case certain registers as not being writable, for example during live migration once dirty page logging is fixed. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Implement kvm_arch_flush_shadow_all/memslotJames Hogan
Implement the kvm_arch_flush_shadow_all() and kvm_arch_flush_shadow_memslot() KVM functions for MIPS to allow guest physical mappings to be safely changed. The general MIPS KVM code takes care of flushing of GPA page table entries. kvm_arch_flush_shadow_all() flushes the whole GPA page table, and is always called on the cleanup path so there is no need to acquire the kvm->mmu_lock. kvm_arch_flush_shadow_memslot() flushes only the range of mappings in the GPA page table corresponding to the slot being flushed, and happens when memory regions are moved or deleted. MIPS KVM implementation callbacks are added for handling the implementation specific flushing of mappings derived from the GPA page tables. These are implemented for trap_emul.c using kvm_flush_remote_tlbs() which should now be functional, and will flush the per-VCPU GVA page tables and ASIDS synchronously (before next entering guest mode or directly accessing GVA space). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Add lockless GVA access helpersJames Hogan
Add helpers to allow for lockless direct access to the GVA space, by changing the VCPU mode to READING_SHADOW_PAGE_TABLES for the duration of the access. This allows asynchronous TLB flush requests in future patches to safely trigger either a TLB flush before the direct GVA space access, or a delay until the in-progress lockless direct access is complete. The kvm_trap_emul_gva_lockless_begin() and kvm_trap_emul_gva_lockless_end() helpers take care of guarding the direct GVA accesses, and kvm_trap_emul_gva_fault() tries to handle a uaccess fault resulting from a flush having taken place. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Reduce stale ASID checksJames Hogan
The stale ASID checks taking place on VCPU load can be reduced: - Now that we check for a stale ASID on guest re-entry, there is no need to do so when loading the VCPU outside of guest context, since it will happen before entering the guest. Note that a lot of KVM VCPU ioctls will cause the VCPU to be loaded but guest context won't be entered. - There is no need to check for a stale kernel_mm ASID when the guest is in user mode and vice versa. In fact doing so can potentially be problematic since the user_mm ASID regeneration may trigger a new ASID cycle, which would cause the kern_mm ASID to become stale after it has been checked for staleness. Therefore only check the ASID for the mm corresponding to the current guest mode, and only if we're already in guest context. We drop some of the related kvm_debug() calls here too. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Handle TLB invalidation requestsJames Hogan
Add handling of TLB invalidation requests before entering guest mode. This will allow asynchonous invalidation of the VCPU mappings when physical memory regions are altered. Should the CPU running the VCPU already be in guest mode an IPI will be sent to trigger a guest exit. The reload_asid path will be used in a future patch for when GVA is about to be directly accessed by KVM. In the process, the stale user ASID check in the re-entry path (for lazy user GVA flushing) is generalised to check the ASID for the current guest mode, in case a TLB invalidation request was handled. This has the side effect of making the ASID checks on vcpu_load too conservative, which will be addressed in a later patch. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Don't treat code fetch faults as MMIOJames Hogan
In order to make use of the CP0_BadInstr & CP0_BadInstrP registers we need to be a bit more careful not to treat code fetch faults as MMIO, lest we hit an UNPREDICTABLE register value when we try to emulate the MMIO load instruction but there was no valid instruction word available to the hardware. Add a kvm_is_ifetch_fault() helper to try to figure out whether a load fault was due to a code fetch, and prevent MMIO instruction emulation in that case. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/MMU: Drop kvm_get_new_mmu_context()James Hogan
MIPS KVM uses its own variation of get_new_mmu_context() which takes an extra vcpu pointer (unused) and does exactly the same thing. Switch to just using get_new_mmu_context() directly and drop KVM's version of it as it doesn't really serve any purpose. The nearby declarations of kvm_mips_alloc_new_mmu_context(), kvm_mips_vcpu_load() and kvm_mips_vcpu_put() are also removed from kvm_host.h, as no definitions or users exist. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Use uaccess to read/modify guest instructionsJames Hogan
Now that we have GVA page tables, use standard user accesses with page faults disabled to read & modify guest instructions. This should be more robust (than the rather dodgy method of accessing guest mapped segments by just directly addressing them) and will also work with Enhanced Virtual Addressing (EVA) host kernel configurations where dedicated instructions are needed for accessing user mode memory. For simplicity and speed we do this regardless of the guest segment the address resides in, rather than handling guest KSeg0 specially with kmap_atomic() as before. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Drop vm_init() callbackJames Hogan
Now that the commpage doesn't use wired TLB entries, the per-CPU vm_init() callback is the only work done by kvm_mips_init_vm_percpu(). The trap & emulate implementation doesn't actually need to do anything from vm_init(), and the future VZ implementation would be better served by a kvm_arch_hardware_enable callback anyway. Therefore drop the vm_init() callback entirely, allowing the kvm_mips_init_vm_percpu() function to also be dropped, along with the kvm_mips_instance atomic counter. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/MMU: Invalidate GVA PTs on ASID changesJames Hogan
Implement invalidation of large ranges of virtual addresses from GVA page tables in response to a guest ASID change (immediately for guest kernel page table, lazily for guest user page table). We iterate through a range of page tables invalidating entries and freeing fully invalidated tables. To minimise overhead the exact ranges invalidated depends on the flags argument to kvm_mips_flush_gva_pt(), which also allows it to be used in future KVM_CAP_SYNC_MMU patches in response to GPA changes, which unlike guest TLB mapping changes affects guest KSeg0 mappings. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Activate GVA page tables in guest contextJames Hogan
Activate the GVA page tables when in guest context. This will allow the normal Linux TLB refill handler to fill from it when guest memory is read, as well as preventing accidental reading from user memory. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Allocate GVA -> HPA page tablesJames Hogan
Allocate GVA -> HPA page tables for guest kernel and guest user mode on each VCPU, to allow for fast path TLB refill handling to be added later. In the process kvm_arch_vcpu_init() needs updating to pass on any error from the vcpu_init() callback. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Wire up vcpu uninitJames Hogan
Wire up a vcpu uninit implementation callback. This will be used for the clean up of GVA->HPA page tables. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: active_mm = init_mm in guest contextJames Hogan
Set init_mm as the active_mm and update mm_cpumask(current->mm) to reflect that it isn't active when in guest context. This prevents cache management code from attempting cache flushes on host virtual addresses while in guest context, for example due to a cache management IPIs or later when writing of dynamically translated code hits copy on write. We do this using helpers in static kernel code to avoid having to export init_mm to modules. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/T&E: Restore host asid on return to hostJames Hogan
We only need the guest ASID loaded while in guest context, i.e. while running guest code and while handling guest exits. We load the guest ASID when entering the guest, however we restore the host ASID later than necessary, when the VCPU state is saved i.e. vcpu_put() or slightly earlier if preempted after returning to the host. This mismatch is both unpleasant and causes redundant host ASID restores in kvm_trap_emul_vcpu_put(). Lets explicitly restore the host ASID when returning to the host, and don't bother restoring the host ASID on context switch in unless we're already in guest context. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Add vcpu_run() & vcpu_reenter() callbacksJames Hogan
Add implementation callbacks for entering the guest (vcpu_run()) and reentering the guest (vcpu_reenter()), allowing implementation specific operations to be performed before entering the guest or after returning to the host without cluttering kvm_arch_vcpu_ioctl_run(). This allows the T&E specific lazy user GVA flush to be moved into trap_emul.c, along with disabling of the HTW. We also move kvm_mips_deliver_interrupts() as VZ will need to restore the guest timer state prior to delivering interrupts. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Remove duplicated ASIDs from vcpuJames Hogan
The kvm_vcpu_arch structure contains both mm_structs for allocating MMU contexts (primarily the ASID) but it also copies the resulting ASIDs into guest_{user,kernel}_asid[] arrays which are referenced from uasm generated code. This duplication doesn't seem to serve any purpose, and it gets in the way of generalising the ASID handling across guest kernel/user modes, so lets just extract the ASID straight out of the mm_struct on demand, and in fact there are convenient cpu_context() and cpu_asid() macros for doing so. To reduce the verbosity of this code we do also add kern_mm and user_mm local variables where the kernel and user mm_structs are used. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS/MMU: Move preempt/ASID handling to implementationJames Hogan
The MIPS KVM host and guest GVA ASIDs may need regenerating when scheduling a process in guest context, which is done from the kvm_arch_vcpu_load() / kvm_arch_vcpu_put() functions in mmu.c. However this is a fairly implementation specific detail. VZ for example may use GuestIDs instead of normal ASIDs to distinguish mappings belonging to different guests, and even on VZ without GuestID the root TLB will be used differently to trap & emulate. Trap & emulate GVA ASIDs only relate to the user part of the full address space, so can be left active during guest exit handling (guest context) to allow guest instructions to be easily read and translated. VZ root ASIDs however are for GPA mappings so can't be left active during normal kernel code. They also aren't useful for accessing guest virtual memory, and we should have CP0_BadInstr[P] registers available to provide encodings of trapping guest instructions anyway. Therefore move the ASID preemption handling into the implementation callback. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2017-02-03KVM: MIPS: Convert get/set_regs -> vcpu_load/putJames Hogan
Convert the get_regs() and set_regs() callbacks to vcpu_load() and vcpu_put(), which provide a cpu argument and more closely match the kvm_arch_vcpu_load() / kvm_arch_vcpu_put() that they are called by. This is in preparation for moving ASID management into the implementations. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2016-10-15Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds
Pull MIPS updates from Ralf Baechle: "This is the main MIPS pull request for 4.9: MIPS core arch code: - traps: 64bit kernels should read CP0_EBase 64bit - traps: Convert ebase to KSEG0 - c-r4k: Drop bc_wback_inv() from icache flush - c-r4k: Split user/kernel flush_icache_range() - cacheflush: Use __flush_icache_user_range() - uprobes: Flush icache via kernel address - KVM: Use __local_flush_icache_user_range() - c-r4k: Fix flush_icache_range() for EVA - Fix -mabi=64 build of vdso.lds - VDSO: Drop duplicated -I*/-E* aflags - tracing: move insn_has_delay_slot to a shared header - tracing: disable uprobe/kprobe on compact branch instructions - ptrace: Fix regs_return_value for kernel context - Squash lines for simple wrapper functions - Move identification of VP(E) into proc.c from smp-mt.c - Add definitions of SYNC barrierstype values - traps: Ensure full EBase is written - tlb-r4k: If there are wired entries, don't use TLBINVF - Sanitise coherentio semantics - dma-default: Don't check hw_coherentio if device is non-coherent - Support per-device DMA coherence - Adjust MIPS64 CAC_BASE to reflect Config.K0 - Support generating Flattened Image Trees (.itb) - generic: Introduce generic DT-based board support - generic: Convert SEAD-3 to a generic board - Enable hardened usercopy - Don't specify STACKPROTECTOR in defconfigs Octeon: - Delete dead code and files across the platform. - Change to use all memory into use by default. - Rename upper case variables in setup code to lowercase. - Delete legacy hack for broken bootloaders. - Leave maintaining the link state to the actual ethernet/PHY drivers. - Add DTS for D-Link DSR-500N. - Fix PCI interrupt routing on D-Link DSR-500N. Pistachio: - Remove ANDROID_TIMED_OUTPUT from defconfig TX39xx: - Move GPIO setup from .mem_setup() to .arch_init() - Convert to Common Clock Framework TX49xx: - Move GPIO setup from .mem_setup() to .arch_init() - Convert to Common Clock Framework txx9wdt: - Add missing clock (un)prepare calls for CCF BMIPS: - Add PW, GPIO SDHCI and NAND device node names - Support APPENDED_DTB - Add missing bcm97435svmb to DT_NONE - Rename bcm96358nb4ser to bcm6358-neufbox4-sercom - Add DT examples for BCM63268, BCM3368 and BCM6362 - Add support for BCM3368 and BCM6362 PCI - Reduce stack frame usage - Use struct list_head lists - Support for CONFIG_PCI_DOMAINS_GENERIC - Make pcibios_set_cache_line_size an initcall - Inline pcibios_assign_all_busses - Split pci.c into pci.c & pci-legacy.c - Introduce CONFIG_PCI_DRIVERS_LEGACY - Support generic drivers CPC - Convert bare 'unsigned' to 'unsigned int' - Avoid lock when MIPS CM >= 3 is present GIC: - Delete unused file smp-gic.c mt7620: - Delete unnecessary assignment for the field "owner" from PCI BCM63xx: - Let clk_disable() return immediately if clk is NULL pm-cps: - Change FSB workaround to CPU blacklist - Update comments on barrier instructions - Use MIPS standard lightweight ordering barrier - Use MIPS standard completion barrier - Remove selection of sync types - Add MIPSr6 CPU support - Support CM3 changes to Coherence Enable Register SMP: - Wrap call to mips_cpc_lock_other in mips_cm_lock_other - Introduce mechanism for freeing and allocating IPIs cpuidle: - cpuidle-cps: Enable use with MIPSr6 CPUs. SEAD3: - Rewrite to use DT and generic kernel feature. USB: - host: ehci-sead3: Remove SEAD-3 EHCI code FBDEV: - cobalt_lcdfb: Drop SEAD3 support dt-bindings: - Document a binding for simple ASCII LCDs auxdisplay: - img-ascii-lcd: driver for simple ASCII LCD displays irqchip i8259: - i8259: Add domain before mapping parent irq - i8259: Allow platforms to override poll function - i8259: Remove unused i8259A_irq_pending Malta: - Rewrite to use DT of/platform: - Probe "isa" busses by default CM: - Print CM error reports upon bus errors Module: - Migrate exception table users off module.h and onto extable.h - Make various drivers explicitly non-modular: - Audit and remove any unnecessary uses of module.h mailmap: - Canonicalize to Qais' current email address. Documentation: - MIPS supports HAVE_REGS_AND_STACK_ACCESS_API Loongson1C: - Add CPU support for Loongson1C - Add board support - Add defconfig - Add RTC support for Loongson1C board All this except one Documentation fix has sat in linux-next and has survived Imagination's automated build test system" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (127 commits) Documentation: MIPS supports HAVE_REGS_AND_STACK_ACCESS_API MIPS: ptrace: Fix regs_return_value for kernel context MIPS: VDSO: Drop duplicated -I*/-E* aflags MIPS: Fix -mabi=64 build of vdso.lds MIPS: Enable hardened usercopy MIPS: generic: Convert SEAD-3 to a generic board MIPS: generic: Introduce generic DT-based board support MIPS: Support generating Flattened Image Trees (.itb) MIPS: Adjust MIPS64 CAC_BASE to reflect Config.K0 MIPS: Print CM error reports upon bus errors MIPS: Support per-device DMA coherence MIPS: dma-default: Don't check hw_coherentio if device is non-coherent MIPS: Sanitise coherentio semantics MIPS: PCI: Support generic drivers MIPS: PCI: Introduce CONFIG_PCI_DRIVERS_LEGACY MIPS: PCI: Split pci.c into pci.c & pci-legacy.c MIPS: PCI: Inline pcibios_assign_all_busses MIPS: PCI: Make pcibios_set_cache_line_size an initcall MIPS: PCI: Support for CONFIG_PCI_DOMAINS_GENERIC MIPS: PCI: Use struct list_head lists ...
2016-10-05MIPS: kvm: Audit and remove any unnecessary uses of module.hPaul Gortmaker
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. In the case of kvm where it is modular, we can extend that to also include files that are building basic support functionality but not related to loading or registering the final module; such files also have no need whatsoever for module.h The advantage in removing such instances is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each instance for the presence of either and replace as needed. In this case, we did not need to add either to any files. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: James Hogan <james.hogan@imgtec.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14036/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-09-08KVM: MIPS: Emulate MMIO via TLB miss for EVAJames Hogan
MIPS Enhanced Virtual Addressing (EVA) allows the virtual memory segments to be rearranged such that the KSeg0/KSeg1 segments are accessible TLB mapped to user mode, which would trigger a TLB Miss exception (due to lack of TLB mappings) instead of an Address Error exception. Update the TLB Miss handling similar to Address Error handling for guest MMIO emulation. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
2016-07-05MIPS: KVM: Emulate generic QEMU machine on r6 T&EJames Hogan
Default the guest PRId register to represent a generic QEMU machine instead of a 24kc on MIPSr6. 24kc isn't supported by r6 Linux kernels. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim KrÄmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-15MIPS: KVM: Use mipsregs.h defs for config registersJames Hogan
Convert MIPS KVM guest register state initialisation to use the standard <asm/mipsregs.h> register field definitions for Config registers, and drop the custom definitions in kvm_host.h which it was using before. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-15MIPS: KVM: Report more accurate CP0_Config fields to guestJames Hogan
Initialise the guest's CP0_Config register with a few more bits of information from the host. The BE bit should be set on big endian machines, the VI bit should be set on machines with a virtually tagged instruction cache, and the reported architecture revision should match that of the host (since we won't support emulating pre-r6 instruction encodings on r6 or vice versa). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-15MIPS: KVM: Add KScratch registersJames Hogan
Allow up to 6 KVM guest KScratch registers to be enabled and accessed via the KVM guest register API and from the guest itself (the fallback reading and writing of commpage registers is sufficient for KScratch registers to work as expected). User mode can expose the registers by setting the appropriate bits of the guest Config4.KScrExist field. KScratch registers that aren't usable won't be writeable via the KVM Ioctl API. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-15MIPS: KVM: Make KVM_GET_REG_LIST dynamicJames Hogan
Make the implementation of KVM_GET_REG_LIST more dynamic so that only the subset of registers actually available can be exposed to user mode. This is important for VZ where some of the guest register state may not be possible to prevent the guest from accessing, therefore the user process may need to be aware of the state even if it doesn't understand what the state is for. This also allows different MIPS KVM implementations to provide different registers to one another, by way of new num_regs(vcpu) and copy_reg_indices(vcpu, indices) callback functions, currently just stubbed for trap & emulate. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Combine handle_tlb_ld/st_missJames Hogan
The handle_tlb_ld/st_miss handlers are logically equivalent and textually almost identical, so combine their implementations into a single kvm_trap_emul_handle_tlb_miss(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Make various Cause variables 32-bitJames Hogan
The CP0 Cause register is passed around in KVM quite a bit, often as an unsigned long, even though it is always 32-bits long. Resize it to u32 throughout MIPS KVM. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Convert code to kernel sized typesJames Hogan
Convert the MIPS KVM C code to use standard kernel sized types (e.g. u32) instead of inttypes.h style ones (e.g. uint32_t) or other types as appropriate. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "Small release overall. x86: - miscellaneous fixes - AVIC support (local APIC virtualization, AMD version) s390: - polling for interrupts after a VCPU goes to halted state is now enabled for s390 - use hardware provided information about facility bits that do not need any hypervisor activity, and other fixes for cpu models and facilities - improve perf output - floating interrupt controller improvements. MIPS: - miscellaneous fixes PPC: - bugfixes only ARM: - 16K page size support - generic firmware probing layer for timer and GIC Christoffer Dall (KVM-ARM maintainer) says: "There are a few changes in this pull request touching things outside KVM, but they should all carry the necessary acks and it made the merge process much easier to do it this way." though actually the irqchip maintainers' acks didn't make it into the patches. Marc Zyngier, who is both irqchip and KVM-ARM maintainer, later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more formally and for documentation purposes')" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits) KVM: MTRR: remove MSR 0x2f8 KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same svm: Manage vcpu load/unload when enable AVIC svm: Do not intercept CR8 when enable AVIC svm: Do not expose x2APIC when enable AVIC KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore svm: Add VMEXIT handlers for AVIC svm: Add interrupt injection via AVIC KVM: x86: Detect and Initialize AVIC support svm: Introduce new AVIC VMCB registers KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg KVM: x86: Misc LAPIC changes to expose helper functions KVM: shrink halt polling even more for invalid wakeups KVM: s390: set halt polling to 80 microseconds KVM: halt_polling: provide a way to qualify wakeups during poll KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts kvm: Conditionally register IRQ bypass consumer ...
2016-05-13MIPS: Define & use CP0_EBase bit definitionsJames Hogan
Add definitions for the bits & fields in the CP0_EBase register, and use them from a few different places in arch/mips which hardcoded these values. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Jayachandran C <jchandra@broadcom.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/13222/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-10MIPS: KVM: Fix timer IRQ race when writing CP0_CompareJames Hogan
Writing CP0_Compare clears the timer interrupt pending bit (CP0_Cause.TI), but this wasn't being done atomically. If a timer interrupt raced with the write of the guest CP0_Compare, the timer interrupt could end up being pending even though the new CP0_Compare is nowhere near CP0_Count. We were already updating the hrtimer expiry with kvm_mips_update_hrtimer(), which used both kvm_mips_freeze_hrtimer() and kvm_mips_resume_hrtimer(). Close the race window by expanding out kvm_mips_update_hrtimer(), and clearing CP0_Cause.TI and setting CP0_Compare between the freeze and resume. Since the pending timer interrupt should not be cleared when CP0_Compare is written via the KVM user API, an ack argument is added to distinguish the source of the write. Fixes: e30492bbe95a ("MIPS: KVM: Rewrite count/compare timer emulation") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: <stable@vger.kernel.org> # 3.16.x- Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>