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2014-12-28kvm: warn on more invariant breakagePaolo Bonzini1-1/+3
Modifying a non-existent slot is not allowed. Also check that the first loop doesn't move a deleted slot beyond the used part of the mslots array. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-28kvm: fix sorting of memslots with base_gfn == 0Paolo Bonzini1-5/+17
Before commit 0e60b0799fed (kvm: change memslot sorting rule from size to GFN, 2014-12-01), the memslots' sorting key was npages, meaning that a valid memslot couldn't have its sorting key equal to zero. On the other hand, a valid memslot can have base_gfn == 0, and invalid memslots are identified by base_gfn == npages == 0. Because of this, commit 0e60b0799fed broke the invariant that invalid memslots are at the end of the mslots array. When a memslot with base_gfn == 0 was created, any invalid memslot before it were left in place. This can be fixed by changing the insertion to use a ">=" comparison instead of "<=", but some care is needed to avoid breaking the case of deleting a memslot; see the comment in update_memslots. Thanks to Tiejun Chen for posting an initial patch for this bug. Reported-by: Jamie Heilman <jamie@audible.transient.net> Reported-by: Andy Lutomirski <luto@amacapital.net> Tested-by: Jamie Heilman <jamie@audible.transient.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-19Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds9-2690/+140
Pull KVM update from Paolo Bonzini: "3.19 changes for KVM: - spring cleaning: removed support for IA64, and for hardware- assisted virtualization on the PPC970 - ARM, PPC, s390 all had only small fixes For x86: - small performance improvements (though only on weird guests) - usual round of hardware-compliancy fixes from Nadav - APICv fixes - XSAVES support for hosts and guests. XSAVES hosts were broken because the (non-KVM) XSAVES patches inadvertently changed the KVM userspace ABI whenever XSAVES was enabled; hence, this part is going to stable. Guest support is just a matter of exposing the feature and CPUID leaves support" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits) KVM: move APIC types to arch/x86/ KVM: PPC: Book3S: Enable in-kernel XICS emulation by default KVM: PPC: Book3S HV: Improve H_CONFER implementation KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register KVM: PPC: Book3S HV: Remove code for PPC970 processors KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions KVM: PPC: Book3S HV: Simplify locking around stolen time calculations arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function arch: powerpc: kvm: book3s_pr.c: Remove unused function arch: powerpc: kvm: book3s.c: Remove some unused functions arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked KVM: PPC: Book3S HV: ptes are big endian KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI KVM: PPC: Book3S HV: Fix KSM memory corruption KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI KVM: PPC: Book3S HV: Fix computation of tlbie operand KVM: PPC: Book3S HV: Add missing HPTE unlock KVM: PPC: BookE: Improve irq inject tracepoint arm/arm64: KVM: Require in-kernel vgic for the arch timers ...
2014-12-15Merge tag 'kvm-arm-for-3.19-take2' of ↵Paolo Bonzini3-72/+90
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD Second round of changes for KVM for arm/arm64 for v3.19; fixes reboot problems, clarifies VCPU init, and fixes a regression concerning the VGIC init flow. Conflicts: arch/ia64/kvm/kvm-ia64.c [deleted in HEAD and modified in kvmarm]
2014-12-15arm/arm64: KVM: Require in-kernel vgic for the arch timersChristoffer Dall1-8/+22
It is curently possible to run a VM with architected timers support without creating an in-kernel VGIC, which will result in interrupts from the virtual timer going nowhere. To address this issue, move the architected timers initialization to the time when we run a VCPU for the first time, and then only initialize (and enable) the architected timers if we have a properly created and initialized in-kernel VGIC. When injecting interrupts from the virtual timer to the vgic, the current setup should ensure that this never calls an on-demand init of the VGIC, which is the only call path that could return an error from kvm_vgic_inject_irq(), so capture the return value and raise a warning if there's an error there. We also change the kvm_timer_init() function from returning an int to be a void function, since the function always succeeds. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-15arm/arm64: KVM: Initialize the vgic on-demand when injecting IRQsChristoffer Dall1-6/+16
Userspace assumes that it can wire up IRQ injections after having created all VCPUs and after having created the VGIC, but potentially before starting the first VCPU. This can currently lead to lost IRQs because the state of that IRQ injection is not stored anywhere and we don't return an error to userspace. We haven't seen this problem manifest itself yet, presumably because guests reset the devices on boot, but this could cause issues with migration and other non-standard startup configurations. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13arm/arm64: KVM: Add (new) vgic_initialized macroChristoffer Dall1-1/+2
Some code paths will need to check to see if the internal state of the vgic has been initialized (such as when creating new VCPUs), so introduce such a macro that checks the nr_cpus field which is set when the vgic has been initialized. Also set nr_cpus = 0 in kvm_vgic_destroy, because the error path in vgic_init() will call this function, and code should never errornously assume the vgic to be properly initialized after an error. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13arm/arm64: KVM: Rename vgic_initialized to vgic_readyChristoffer Dall1-3/+3
The vgic_initialized() macro currently returns the state of the vgic->ready flag, which indicates if the vgic is ready to be used when running a VM, not specifically if its internal state has been initialized. Rename the macro accordingly in preparation for a more nuanced initialization flow. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13arm/arm64: KVM: vgic: move reset initialization into vgic_init_maps()Peter Maydell1-45/+32
VGIC initialization currently happens in three phases: (1) kvm_vgic_create() (triggered by userspace GIC creation) (2) vgic_init_maps() (triggered by userspace GIC register read/write requests, or from kvm_vgic_init() if not already run) (3) kvm_vgic_init() (triggered by first VM run) We were doing initialization of some state to correspond with the state of a freshly-reset GIC in kvm_vgic_init(); this is too late, since it will overwrite changes made by userspace using the register access APIs before the VM is run. Move this initialization earlier, into the vgic_init_maps() phase. This fixes a bug where QEMU could successfully restore a saved VM state snapshot into a VM that had already been run, but could not restore it "from cold" using the -loadvm command line option (the symptoms being that the restored VM would run but interrupts were ignored). Finally rename vgic_init_maps to vgic_init and renamed kvm_vgic_init to kvm_vgic_map_resources. [ This patch is originally written by Peter Maydell, but I have modified it somewhat heavily, renaming various bits and moving code around. If something is broken, I am to be blamed. - Christoffer ] Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-04KVM: track pid for VCPU only on KVM_RUN ioctlChristian Borntraeger1-9/+9
We currently track the pid of the task that runs the VCPU in vcpu_load. If a yield to that VCPU is triggered while the PID of the wrong thread is active, the wrong thread might receive a yield, but this will most likely not help the executing thread at all. Instead, if we only track the pid on the KVM_RUN ioctl, there are two possibilities: 1) the thread that did a non-KVM_RUN ioctl is holding a mutex that the VCPU thread is waiting for. In this case, the VCPU thread is not runnable, but we also do not do a wrong yield. 2) the thread that did a non-KVM_RUN ioctl is sleeping, or doing something that does not block the VCPU thread. In this case, the VCPU thread can receive the directed yield correctly. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> CC: Rik van Riel <riel@redhat.com> CC: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> CC: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-04KVM: don't check for PF_VCPU when yieldingDavid Hildenbrand1-4/+0
kvm_enter_guest() has to be called with preemption disabled and will set PF_VCPU. Current code takes PF_VCPU as a hint that the VCPU thread is running and therefore needs no yield. However, the check on PF_VCPU is wrong on s390, where preemption has to stay enabled in order to correctly process page faults. Thus, s390 reenables preemption and starts to execute the guest. The thread might be scheduled out between kvm_enter_guest() and kvm_exit_guest(), resulting in PF_VCPU being set but not being run. When this happens, the opportunity for directed yield is missed. However, this check is done already in kvm_vcpu_on_spin before calling kvm_vcpu_yield_loop: if (!ACCESS_ONCE(vcpu->preempted)) continue; so the check on PF_VCPU is superfluous in general, and this patch removes it. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-04kvm: optimize GFN to memslot lookup with large slots amountIgor Mammedov1-1/+7
Current linear search doesn't scale well when large amount of memslots is used and looked up slot is not in the beginning memslots array. Taking in account that memslots don't overlap, it's possible to switch sorting order of memslots array from 'npages' to 'base_gfn' and use binary search for memslot lookup by GFN. As result of switching to binary search lookup times are reduced with large amount of memslots. Following is a table of search_memslot() cycles during WS2008R2 guest boot. boot, boot + ~10 min mostly same of using it, slot lookup randomized lookup max average average cycles cycles cycles 13 slots : 1450 28 30 13 slots : 1400 30 40 binary search 117 slots : 13000 30 460 117 slots : 2000 35 180 binary search Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-04kvm: change memslot sorting rule from size to GFNIgor Mammedov1-6/+11
it will allow to use binary search for GFN -> memslot lookups, reducing lookup cost with large slots amount. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-04kvm: update_memslots: drop not needed check for the same slotIgor Mammedov1-14/+11
UP/DOWN shift loops will shift array in needed direction and stop at place where new slot should be placed regardless of old slot size. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-04kvm: update_memslots: drop not needed check for the same number of pagesIgor Mammedov1-15/+13
if number of pages haven't changed sorting algorithm will do nothing, so there is no need to do extra check to avoid entering sorting logic. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-26kvm: fix kvm_is_mmio_pfn() and rename to kvm_is_reserved_pfn()Ard Biesheuvel1-8/+8
This reverts commit 85c8555ff0 ("KVM: check for !is_zero_pfn() in kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn. The problem being addressed by the patch above was that some ARM code based the memory mapping attributes of a pfn on the return value of kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should be mapped as device memory. However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin, and the existing non-ARM users were already using it in a way which suggests that its name should probably have been 'kvm_is_reserved_pfn' from the beginning, e.g., whether or not to call get_page/put_page on it etc. This means that returning false for the zero page is a mistake and the patch above should be reverted. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-26arm/arm64: KVM: vgic: Fix error code in kvm_vgic_create()Christoffer Dall1-4/+4
If we detect another vCPU is running we just exit and return 0 as if we succesfully created the VGIC, but the VGIC wouldn't actual be created. This shouldn't break in-kernel behavior because the kernel will not observe the failed the attempt to create the VGIC, but userspace could be rightfully confused. Cc: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-26arm/arm64: KVM: vgic: kick the specific vcpu instead of iterating through allShannon Zhao1-5/+10
When call kvm_vgic_inject_irq to inject interrupt, we can known which vcpu the interrupt for by the irq_num and the cpuid. So we should just kick this vcpu to avoid iterating through all. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-25arm/arm64: vgic: Remove unreachable irq_clear_pendingChristoffer Dall1-2/+0
When 'injecting' an edge-triggered interrupt with a falling edge we shouldn't clear the pending state on the distributor. In fact, we don't, because the check in vgic_validate_injection would prevent us from ever reaching this bit of code. Remove the unreachable snippet. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-25kvm: fix kvm_is_mmio_pfn() and rename to kvm_is_reserved_pfn()Ard Biesheuvel1-8/+8
This reverts commit 85c8555ff0 ("KVM: check for !is_zero_pfn() in kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn. The problem being addressed by the patch above was that some ARM code based the memory mapping attributes of a pfn on the return value of kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should be mapped as device memory. However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin, and the existing non-ARM users were already using it in a way which suggests that its name should probably have been 'kvm_is_reserved_pfn' from the beginning, e.g., whether or not to call get_page/put_page on it etc. This means that returning false for the zero page is a mistake and the patch above should be reverted. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-25KVM: ARM: VGIC: Optimize the vGIC vgic_update_irq_pending function.wanghaibin1-0/+3
When vgic_update_irq_pending with level-sensitive false, it is need to deactivates an interrupt, and, it can go to out directly. Here return a false value, because it will be not need to kick. Signed-off-by: wanghaibin <wanghaibin.wang@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-23kvm: x86: move assigned-dev.c and iommu.c to arch/x86/Radim Krčmář3-1386/+0
Now that ia64 is gone, we can hide deprecated device assignment in x86. Notable changes: - kvm_vm_ioctl_assigned_device() was moved to x86/kvm_arch_vm_ioctl() The easy parts were removed from generic kvm code, remaining - kvm_iommu_(un)map_pages() would require new code to be moved - struct kvm_assigned_dev_kernel depends on struct kvm_irq_ack_notifier Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-21kvm: x86: move ioapic.c and irq_comm.c back to arch/x86/Paolo Bonzini5-1142/+0
ia64 does not need them anymore. Ack notifiers become x86-specific too. Suggested-by: Gleb Natapov <gleb@kernel.org> Reviewed-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-20KVM: ia64: removePaolo Bonzini3-28/+0
KVM for ia64 has been marked as broken not just once, but twice even, and the last patch from the maintainer is now roughly 5 years old. Time for it to rest in peace. Acked-by: Gleb Natapov <gleb@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-17kvm: simplify update_memslots invocationPaolo Bonzini1-14/+6
The update_memslots invocation is only needed in one case. Make the code clearer by moving it to __kvm_set_memory_region, and removing the wrapper around insert_memslot. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-17kvm: commonize allocation of the new memory slotsPaolo Bonzini1-17/+11
The two kmemdup invocations can be unified. I find that the new placement of the comment makes it easier to see what happens. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-14kvm: memslots: track id_to_index changes during the insertion sortPaolo Bonzini1-19/+19
This completes the optimization from the previous patch, by removing the KVM_MEM_SLOTS_NUM-iteration loop from insert_memslot. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-14kvm: memslots: replace heap sort with an insertion sort passIgor Mammedov1-28/+28
memslots is a sorted array. When a slot is changed, heapsort (lib/sort.c) would take O(n log n) time to update it; an optimized insertion sort will only cost O(n) on an array with just one item out of order. Replace sort() with a custom sort that takes advantage of memslots usage pattern and the known position of the changed slot. performance change of 128 memslots insertions with gradually increasing size (the worst case): heap sort custom sort max: 249747 2500 cycles with custom sort alg taking ~98% less then original update time. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-03KVM: trivial fix comment regarding __kvm_set_memory_regionDominik Dingel1-1/+1
commit 72dc67a69690 ("KVM: remove the usage of the mmap_sem for the protection of the memory slots.") changed the lock which will be taken. This should be reflected in the function commentary. Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-03KVM: x86: some apic broadcast modes does not workNadav Amit1-1/+1
KVM does not deliver x2APIC broadcast messages with physical mode. Intel SDM (10.12.9 ICR Operation in x2APIC Mode) states: "A destination ID value of FFFF_FFFFH is used for broadcast of interrupts in both logical destination and physical destination modes." In addition, the local-apic enables cluster mode broadcast. As Intel SDM 10.6.2.2 says: "Broadcast to all local APICs is achieved by setting all destination bits to one." This patch enables cluster mode broadcast. The fix tries to combine broadcast in different modes through a unified code. One rare case occurs when the source of IPI has its APIC disabled. In such case, the source can still issue IPIs, but since the source is not obliged to have the same LAPIC mode as the enabled ones, we cannot rely on it. Since it is a rare case, it is unoptimized and done on the slow-path. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com> [As per Radim's review, use unsigned int for X2APIC_BROADCAST, return bool from kvm_apic_broadcast. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24kvm: vfio: fix unregister kvm_device_ops of vfioWanpeng Li3-0/+16
After commit 80ce163 (KVM: VFIO: register kvm_device_ops dynamically), kvm_device_ops of vfio can be registered dynamically. Commit 3c3c29fd (kvm-vfio: do not use module_init) move the dynamic register invoked by kvm_init in order to fix broke unloading of the kvm module. However, kvm_device_ops of vfio is unregistered after rmmod kvm-intel module which lead to device type collision detection warning after kvm-intel module reinsmod. WARNING: CPU: 1 PID: 10358 at /root/cathy/kvm/arch/x86/kvm/../../../virt/kvm/kvm_main.c:3289 kvm_init+0x234/0x282 [kvm]() Modules linked in: kvm_intel(O+) kvm(O) nfsv3 nfs_acl auth_rpcgss oid_registry nfsv4 dns_resolver nfs fscache lockd sunrpc pci_stub bridge stp llc autofs4 8021q cpufreq_ondemand ipv6 joydev microcode pcspkr igb i2c_algo_bit ehci_pci ehci_hcd e1000e i2c_i801 ixgbe ptp pps_core hwmon mdio tpm_tis tpm ipmi_si ipmi_msghandler acpi_cpufreq isci libsas scsi_transport_sas button dm_mirror dm_region_hash dm_log dm_mod [last unloaded: kvm_intel] CPU: 1 PID: 10358 Comm: insmod Tainted: G W O 3.17.0-rc1 #2 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013 0000000000000cd9 ffff880ff08cfd18 ffffffff814a61d9 0000000000000cd9 0000000000000000 ffff880ff08cfd58 ffffffff810417b7 ffff880ff08cfd48 ffffffffa045bcac ffffffffa049c420 0000000000000040 00000000000000ff Call Trace: [<ffffffff814a61d9>] dump_stack+0x49/0x60 [<ffffffff810417b7>] warn_slowpath_common+0x7c/0x96 [<ffffffffa045bcac>] ? kvm_init+0x234/0x282 [kvm] [<ffffffff810417e6>] warn_slowpath_null+0x15/0x17 [<ffffffffa045bcac>] kvm_init+0x234/0x282 [kvm] [<ffffffffa016e995>] vmx_init+0x1bf/0x42a [kvm_intel] [<ffffffffa016e7d6>] ? vmx_check_processor_compat+0x64/0x64 [kvm_intel] [<ffffffff810002ab>] do_one_initcall+0xe3/0x170 [<ffffffff811168a9>] ? __vunmap+0xad/0xb8 [<ffffffff8109c58f>] do_init_module+0x2b/0x174 [<ffffffff8109d414>] load_module+0x43e/0x569 [<ffffffff8109c6d8>] ? do_init_module+0x174/0x174 [<ffffffff8109c75a>] ? copy_module_from_user+0x39/0x82 [<ffffffff8109b7dd>] ? module_sect_show+0x20/0x20 [<ffffffff8109d65f>] SyS_init_module+0x54/0x81 [<ffffffff814a9a12>] system_call_fastpath+0x16/0x1b ---[ end trace 0626f4a3ddea56f3 ]--- The bug can be reproduced by: rmmod kvm_intel.ko insmod kvm_intel.ko without rmmod/insmod kvm.ko This patch fixes the bug by unregistering kvm_device_ops of vfio when the kvm-intel module is removed. Reported-by: Liu Rongrong <rongrongx.liu@intel.com> Fixes: 3c3c29fd0d7cddc32862c350d0700ce69953e3bd Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24kvm: fix excessive pages un-pinning in kvm_iommu_map error path.Quentin Casasnovas1-4/+4
The third parameter of kvm_unpin_pages() when called from kvm_iommu_map_pages() is wrong, it should be the number of pages to un-pin and not the page size. This error was facilitated with an inconsistent API: kvm_pin_pages() takes a size, but kvn_unpin_pages() takes a number of pages, so fix the problem by matching the two. This was introduced by commit 350b8bd ("kvm: iommu: fix the third parameter of kvm_iommu_put_pages (CVE-2014-3601)"), which fixes the lack of un-pinning for pages intended to be un-pinned (i.e. memory leak) but unfortunately potentially aggravated the number of pages we un-pin that should have stayed pinned. As far as I understand though, the same practical mitigations apply. This issue was found during review of Red Hat 6.6 patches to prepare Ksplice rebootless updates. Thanks to Vegard for his time on a late Friday evening to help me in understanding this code. Fixes: 350b8bd ("kvm: iommu: fix the third parameter of... (CVE-2014-3601)") Cc: stable@vger.kernel.org Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Jamie Iles <jamie.iles@oracle.com> Reviewed-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-19Merge tag 'kvm-arm-for-3.18-take-2' of ↵Linus Torvalds2-24/+21
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm Pull second batch of changes for KVM/{arm,arm64} from Marc Zyngier: "The most obvious thing is the sizeable MMU changes to support 48bit VAs on arm64. Summary: - support for 48bit IPA and VA (EL2) - a number of fixes for devices mapped into guests - yet another VGIC fix for BE - a fix for CPU hotplug - a few compile fixes (disabled VGIC, strict mm checks)" [ I'm pulling directly from Marc at the request of Paolo Bonzini, whose backpack was stolen at Düsseldorf airport and will do new keys and rebuild his web of trust. - Linus ] * tag 'kvm-arm-for-3.18-take-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm: arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regs arm: kvm: STRICT_MM_TYPECHECKS fix for user_mem_abort arm/arm64: KVM: Ensure memslots are within KVM_PHYS_SIZE arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 arm/arm64: KVM: map MMIO regions at creation time arm64: kvm: define PAGE_S2_DEVICE as read-only by default ARM: kvm: define PAGE_S2_DEVICE as read-only by default arm/arm64: KVM: add 'writable' parameter to kvm_phys_addr_ioremap arm/arm64: KVM: fix potential NULL dereference in user_mem_abort() arm/arm64: KVM: use __GFP_ZERO not memset() to get zeroed pages ARM: KVM: fix vgic-disabled build arm: kvm: fix CPU hotplug
2014-10-16arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regsChristoffer Dall2-23/+19
The EIRSR and ELRSR registers are 32-bit registers on GICv2, and we store these as an array of two such registers on the vgic vcpu struct. However, we access them as a single 64-bit value or as a bitmap pointer in the generic vgic code, which breaks BE support. Instead, store them as u64 values on the vgic structure and do the word-swapping in the assembly code, which already handles the byte order for BE systems. Tested-by: Victor Kamensky <victor.kamensky@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-15Merge tag 'iommu-updates-v3.18' of ↵Linus Torvalds1-4/+2
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: "This pull-request includes: - change in the IOMMU-API to convert the former iommu_domain_capable function to just iommu_capable - various fixes in handling RMRR ranges for the VT-d driver (one fix requires a device driver core change which was acked by Greg KH) - the AMD IOMMU driver now assigns and deassigns complete alias groups to fix issues with devices using the wrong PCI request-id - MMU-401 support for the ARM SMMU driver - multi-master IOMMU group support for the ARM SMMU driver - various other small fixes all over the place" * tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits) iommu/vt-d: Work around broken RMRR firmware entries iommu/vt-d: Store bus information in RMRR PCI device path iommu/vt-d: Only remove domain when device is removed driver core: Add BUS_NOTIFY_REMOVED_DEVICE event iommu/amd: Fix devid mapping for ivrs_ioapic override iommu/irq_remapping: Fix the regression of hpet irq remapping iommu: Fix bus notifier breakage iommu/amd: Split init_iommu_group() from iommu_init_device() iommu: Rework iommu_group_get_for_pci_dev() iommu: Make of_device_id array const amd_iommu: do not dereference a NULL pointer address. iommu/omap: Remove omap_iommu unused owner field iommu: Remove iommu_domain_has_cap() API function IB/usnic: Convert to use new iommu_capable() API function vfio: Convert to use new iommu_capable() API function kvm: iommu: Convert to use new iommu_capable() API function iommu/tegra: Convert to iommu_capable() API function iommu/msm: Convert to iommu_capable() API function iommu/vt-d: Convert to iommu_capable() API function iommu/fsl: Convert to iommu_capable() API function ...
2014-10-10arm/arm64: KVM: add 'writable' parameter to kvm_phys_addr_ioremapArd Biesheuvel1-1/+2
Add support for read-only MMIO passthrough mappings by adding a 'writable' parameter to kvm_phys_addr_ioremap. For the moment, mappings will be read-write even if 'writable' is false, but once the definition of PAGE_S2_DEVICE gets changed, those mappings will be created read-only. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-09Merge tag 'pci-v3.18-changes' of ↵Linus Torvalds2-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "The interesting things here are: - Turn on Config Request Retry Status Software Visibility. This caused hangs last time, but we included a fix this time. - Rework PCI device configuration to use _HPP/_HPX more aggressively - Allow PCI devices to be put into D3cold during system suspend - Add arm64 PCI support - Add APM X-Gene host bridge driver - Add TI Keystone host bridge driver - Add Xilinx AXI host bridge driver More detailed summary: Enumeration - Check Vendor ID only for Config Request Retry Status (Rajat Jain) - Enable Config Request Retry Status when supported (Rajat Jain) - Add generic domain handling (Catalin Marinas) - Generate uppercase hex for modalias interface class (Ricardo Ribalda Delgado) Resource management - Add missing MEM_64 mask in pci_assign_unassigned_bridge_resources() (Yinghai Lu) - Increase IBM ipr SAS Crocodile BARs to at least system page size (Douglas Lehr) PCI device hotplug - Prevent NULL dereference during pciehp probe (Andreas Noever) - Move _HPP & _HPX handling into core (Bjorn Helgaas) - Apply _HPP to PCIe devices as well as PCI (Bjorn Helgaas) - Apply _HPP/_HPX to display devices (Bjorn Helgaas) - Preserve SERR & PARITY settings when applying _HPP/_HPX (Bjorn Helgaas) - Preserve MPS and MRRS settings when applying _HPP/_HPX (Bjorn Helgaas) - Apply _HPP/_HPX to all devices, not just hot-added ones (Bjorn Helgaas) - Fix wait time in pciehp timeout message (Yinghai Lu) - Add more pciehp Slot Control debug output (Yinghai Lu) - Stop disabling pciehp notifications during init (Yinghai Lu) MSI - Remove arch_msi_check_device() (Alexander Gordeev) - Rename pci_msi_check_device() to pci_msi_supported() (Alexander Gordeev) - Move D0 check into pci_msi_check_device() (Alexander Gordeev) - Remove unused kobject from struct msi_desc (Yijing Wang) - Remove "pos" from the struct msi_desc msi_attrib (Yijing Wang) - Add "msi_bus" sysfs MSI/MSI-X control for endpoints (Yijing Wang) - Use __get_cached_msi_msg() instead of get_cached_msi_msg() (Yijing Wang) - Use __read_msi_msg() instead of read_msi_msg() (Yijing Wang) - Use __write_msi_msg() instead of write_msi_msg() (Yijing Wang) Power management - Drop unused runtime PM support code for PCIe ports (Rafael J. Wysocki) - Allow PCI devices to be put into D3cold during system suspend (Rafael J. Wysocki) AER - Add additional AER error strings (Gong Chen) - Make <linux/aer.h> standalone includable (Thierry Reding) Virtualization - Add ACS quirk for Solarflare SFC9120 & SFC9140 (Alex Williamson) - Add ACS quirk for Intel 10G NICs (Alex Williamson) - Add ACS quirk for AMD A88X southbridge (Marti Raudsepp) - Remove unused pci_find_upstream_pcie_bridge(), pci_get_dma_source() (Alex Williamson) - Add device flag helpers (Ethan Zhao) - Assume all Mellanox devices have broken INTx masking (Gavin Shan) Generic host bridge driver - Fix ioport_map() for !CONFIG_GENERIC_IOMAP (Liviu Dudau) - Add pci_register_io_range() and pci_pio_to_address() (Liviu Dudau) - Define PCI_IOBASE as the base of virtual PCI IO space (Liviu Dudau) - Fix the conversion of IO ranges into IO resources (Liviu Dudau) - Add pci_get_new_domain_nr() and of_get_pci_domain_nr() (Liviu Dudau) - Add support for parsing PCI host bridge resources from DT (Liviu Dudau) - Add pci_remap_iospace() to map bus I/O resources (Liviu Dudau) - Add arm64 architectural support for PCI (Liviu Dudau) APM X-Gene - Add APM X-Gene PCIe driver (Tanmay Inamdar) - Add arm64 DT APM X-Gene PCIe device tree nodes (Tanmay Inamdar) Freescale i.MX6 - Probe in module_init(), not fs_initcall() (Lucas Stach) - Delay enabling reference clock for SS until it stabilizes (Tim Harvey) Marvell MVEBU - Fix uninitialized variable in mvebu_get_tgt_attr() (Thomas Petazzoni) NVIDIA Tegra - Make sure the PCIe PLL is really reset (Eric Yuen) - Add error path tegra_msi_teardown_irq() cleanup (Jisheng Zhang) - Fix extended configuration space mapping (Peter Daifuku) - Implement resource hierarchy (Thierry Reding) - Clear CLKREQ# enable on port disable (Thierry Reding) - Add Tegra124 support (Thierry Reding) ST Microelectronics SPEAr13xx - Pass config resource through reg property (Pratyush Anand) Synopsys DesignWare - Use NULL instead of false (Fabio Estevam) - Parse bus-range property from devicetree (Lucas Stach) - Use pci_create_root_bus() instead of pci_scan_root_bus() (Lucas Stach) - Remove pci_assign_unassigned_resources() (Lucas Stach) - Check private_data validity in single place (Lucas Stach) - Setup and clear exactly one MSI at a time (Lucas Stach) - Remove open-coded bitmap operations (Lucas Stach) - Fix configuration base address when using 'reg' (Minghuan Lian) - Fix IO resource end address calculation (Minghuan Lian) - Rename get_msi_data() to get_msi_addr() (Minghuan Lian) - Add get_msi_data() to pcie_host_ops (Minghuan Lian) - Add support for v3.65 hardware (Murali Karicheri) - Fold struct pcie_port_info into struct pcie_port (Pratyush Anand) TI Keystone - Add TI Keystone PCIe driver (Murali Karicheri) - Limit MRSS for all downstream devices (Murali Karicheri) - Assume controller is already in RC mode (Murali Karicheri) - Set device ID based on SoC to support multiple ports (Murali Karicheri) Xilinx AXI - Add Xilinx AXI PCIe driver (Srikanth Thokala) - Fix xilinx_pcie_assign_msi() return value test (Dan Carpenter) Miscellaneous - Clean up whitespace (Quentin Lambert) - Remove assignments from "if" conditions (Quentin Lambert) - Move PCI_VENDOR_ID_VMWARE to pci_ids.h (Francesco Ruggeri) - x86: Mark DMI tables as initialization data (Mathias Krause) - x86: Move __init annotation to the correct place (Mathias Krause) - x86: Mark constants of pci_mmcfg_nvidia_mcp55() as __initconst (Mathias Krause) - x86: Constify pci_mmcfg_probes[] array (Mathias Krause) - x86: Mark PCI BIOS initialization code as such (Mathias Krause) - Parenthesize PCI_DEVID and PCI_VPD_LRDT_ID parameters (Megan Kamiya) - Remove unnecessary variable in pci_add_dynid() (Tobias Klauser)" * tag 'pci-v3.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (109 commits) arm64: dts: Add APM X-Gene PCIe device tree nodes PCI: Add ACS quirk for AMD A88X southbridge devices PCI: xgene: Add APM X-Gene PCIe driver PCI: designware: Remove open-coded bitmap operations PCI/MSI: Remove unnecessary temporary variable PCI/MSI: Use __write_msi_msg() instead of write_msi_msg() MSI/powerpc: Use __read_msi_msg() instead of read_msi_msg() PCI/MSI: Use __get_cached_msi_msg() instead of get_cached_msi_msg() PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpoints PCI/MSI: Remove "pos" from the struct msi_desc msi_attrib PCI/MSI: Remove unused kobject from struct msi_desc PCI/MSI: Rename pci_msi_check_device() to pci_msi_supported() PCI/MSI: Move D0 check into pci_msi_check_device() PCI/MSI: Remove arch_msi_check_device() irqchip: armada-370-xp: Remove arch_msi_check_device() PCI/MSI/PPC: Remove arch_msi_check_device() arm64: Add architectural support for PCI PCI: Add pci_remap_iospace() to map bus I/O resources of/pci: Add support for parsing PCI host bridge resources from DT of/pci: Add pci_get_new_domain_nr() and of_get_pci_domain_nr() ... Conflicts: arch/arm64/boot/dts/apm-storm.dtsi
2014-10-08Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds8-248/+779
Pull KVM updates from Paolo Bonzini: "Fixes and features for 3.18. Apart from the usual cleanups, here is the summary of new features: - s390 moves closer towards host large page support - PowerPC has improved support for debugging (both inside the guest and via gdbstub) and support for e6500 processors - ARM/ARM64 support read-only memory (which is necessary to put firmware in emulated NOR flash) - x86 has the usual emulator fixes and nested virtualization improvements (including improved Windows support on Intel and Jailhouse hypervisor support on AMD), adaptive PLE which helps overcommitting of huge guests. Also included are some patches that make KVM more friendly to memory hot-unplug, and fixes for rare caching bugs. Two patches have trivial mm/ parts that were acked by Rik and Andrew. Note: I will soon switch to a subkey for signing purposes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (157 commits) kvm: do not handle APIC access page if in-kernel irqchip is not in use KVM: s390: count vcpu wakeups in stat.halt_wakeup KVM: s390/facilities: allow TOD-CLOCK steering facility bit KVM: PPC: BOOK3S: HV: CMA: Reserve cma region only in hypervisor mode arm/arm64: KVM: Report correct FSC for unsupported fault types arm/arm64: KVM: Fix VTTBR_BADDR_MASK and pgd alloc kvm: Fix kvm_get_page_retry_io __gup retval check arm/arm64: KVM: Fix set_clear_sgi_pend_reg offset kvm: x86: Unpin and remove kvm_arch->apic_access_page kvm: vmx: Implement set_apic_access_page_addr kvm: x86: Add request bit to reload APIC access page address kvm: Add arch specific mmu notifier for page invalidation kvm: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make it non-static kvm: Fix page ageing bugs kvm/x86/mmu: Pass gfn and level to rmapp callback. x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only kvm: x86: use macros to compute bank MSRs KVM: x86: Remove debug assertion of non-PAE reserved bits kvm: don't take vcpu mutex for obviously invalid vcpu ioctls kvm: Faults which trigger IO release the mmap_sem ...
2014-10-02Merge branches 'arm/exynos', 'arm/omap', 'arm/smmu', 'x86/vt-d', 'x86/amd' ↵Joerg Roedel1-4/+2
and 'core' into next Conflicts: drivers/iommu/arm-smmu.c
2014-09-27Merge tag 'kvm-arm-for-3.18' of ↵Paolo Bonzini2-122/+520
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next Changes for KVM for arm/arm64 for 3.18 This includes a bunch of changes: - Support read-only memory slots on arm/arm64 - Various changes to fix Sparse warnings - Correctly detect write vs. read Stage-2 faults - Various VGIC cleanups and fixes - Dynamic VGIC data strcuture sizing - Fix SGI set_clear_pend offset bug - Fix VTTBR_BADDR Mask - Correctly report the FSC on Stage-2 faults Conflicts: virt/kvm/eventfd.c [duplicate, different patch where the kvm-arm version broke x86. The kvm tree instead has the right one]
2014-09-26kvm: Fix kvm_get_page_retry_io __gup retval checkAndres Lagar-Cavilla1-1/+1
Confusion around -EBUSY and zero (inside a BUG_ON no less). Reported-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-25arm/arm64: KVM: Fix set_clear_sgi_pend_reg offsetChristoffer Dall1-2/+2
The sgi values calculated in read_set_clear_sgi_pend_reg() and write_set_clear_sgi_pend_reg() were horribly incorrectly multiplied by 4 with catastrophic results in that subfunctions ended up overwriting memory not allocated for the expected purpose. This showed up as bugs in kfree() and the kernel complaining a lot of you turn on memory debugging. This addresses: http://marc.info/?l=kvm&m=141164910007868&w=2 Reported-by: Shannon Zhao <zhaoshenglong@huawei.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-09-25kvm: iommu: Convert to use new iommu_capable() API functionJoerg Roedel1-4/+2
Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-24kvm: Add arch specific mmu notifier for page invalidationTang Chen1-0/+3
This will be used to let the guest run while the APIC access page is not pinned. Because subsequent patches will fill in the function for x86, place the (still empty) x86 implementation in the x86.c file instead of adding an inline function in kvm_host.h. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24kvm: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make ↵Tang Chen1-5/+5
it non-static Different architectures need different requests, and in fact we will use this function in architecture-specific code later. This will be outside kvm_main.c, so make it non-static and rename it to kvm_make_all_cpus_request(). Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24kvm: Fix page ageing bugsAndres Lagar-Cavilla1-2/+3
1. We were calling clear_flush_young_notify in unmap_one, but we are within an mmu notifier invalidate range scope. The spte exists no more (due to range_start) and the accessed bit info has already been propagated (due to kvm_pfn_set_accessed). Simply call clear_flush_young. 2. We clear_flush_young on a primary MMU PMD, but this may be mapped as a collection of PTEs by the secondary MMU (e.g. during log-dirty). This required expanding the interface of the clear_flush_young mmu notifier, so a lot of code has been trivially touched. 3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate the access bit by blowing the spte. This requires proper synchronizing with MMU notifier consumers, like every other removal of spte's does. Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24kvm: don't take vcpu mutex for obviously invalid vcpu ioctlsDavid Matlack1-0/+4
vcpu ioctls can hang the calling thread if issued while a vcpu is running. However, invalid ioctls can happen when userspace tries to probe the kind of file descriptors (e.g. isatty() calls ioctl(TCGETS)); in that case, we know the ioctl is going to be rejected as invalid anyway and we can fail before trying to take the vcpu mutex. This patch does not change functionality, it just makes invalid ioctls fail faster. Cc: stable@vger.kernel.org Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24kvm: Faults which trigger IO release the mmap_semAndres Lagar-Cavilla2-6/+47
When KVM handles a tdp fault it uses FOLL_NOWAIT. If the guest memory has been swapped out or is behind a filemap, this will trigger async readahead and return immediately. The rationale is that KVM will kick back the guest with an "async page fault" and allow for some other guest process to take over. If async PFs are enabled the fault is retried asap from an async workqueue. If not, it's retried immediately in the same code path. In either case the retry will not relinquish the mmap semaphore and will block on the IO. This is a bad thing, as other mmap semaphore users now stall as a function of swap or filemap latency. This patch ensures both the regular and async PF path re-enter the fault allowing for the mmap semaphore to be relinquished in the case of IO wait. Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24kvm-vfio: do not use module_initPaolo Bonzini3-2/+19
/me got confused between the kernel and QEMU. In the kernel, you can only have one module_init function, and it will prevent unloading the module unless you also have the corresponding module_exit function. So, commit 80ce1639727e (KVM: VFIO: register kvm_device_ops dynamically, 2014-09-02) broke unloading of the kvm module, by adding a module_init function and no module_exit. Repair it by making kvm_vfio_ops_init weak, and checking it in kvm_init. Cc: Will Deacon <will.deacon@arm.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: Alex Williamson <Alex.Williamson@redhat.com> Fixes: 80ce1639727e9d38729c34f162378508c307ca25 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24KVM: EVENTFD: Remove inclusion of irq.hChristoffer Dall1-1/+3
Commit c77dcac (KVM: Move more code under CONFIG_HAVE_KVM_IRQFD) added functionality that depends on definitions in ioapic.h when __KVM_HAVE_IOAPIC is defined. At the same time, kvm-arm commit 0ba0951 (KVM: EVENTFD: remove inclusion of irq.h) removed the inclusion of irq.h, an architecture-specific header that is not present on ARM but which happened to include ioapic.h on x86. Include ioapic.h directly in eventfd.c if __KVM_HAVE_IOAPIC is defined. This fixes x86 and lets ARM use eventfd.c. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>