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* KVM: Fix overlapping check for memory slotsJan Kiszka2009-04-221-1/+2
| | | | | | | | | | | | When checking for overlapping slots on registration of a new one, kvm currently also considers zero-length (ie. deleted) slots and rejects requests incorrectly. This finally denies user space from joining slots. Fix the check by skipping deleted slots and advertise this via a KVM_CAP_JOIN_MEMORY_REGIONS_WORKS. Cc: stable@kernel.org Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: MMU: Fix off-by-one calculating large page countAvi Kivity2009-04-221-5/+3
| | | | | | | | | | The large page initialization code concludes there are two large pages spanned by a slot covering 1 (small) page starting at gfn 1. This is incorrect, and also results in incorrect write_count initialization in some cases (base = 1, npages = 513 for example). Cc: stable@kernel.org Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Get support IRQ routing entry countsSheng Yang2009-03-241-1/+1
| | | | | | | In capability probing ioctl. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: fix sparse warnings: Should it be static?Hannes Eder2009-03-241-2/+2
| | | | | | | | | | | | | | | Impact: Make symbols static. Fix this sparse warnings: arch/x86/kvm/mmu.c:992:5: warning: symbol 'mmu_pages_add' was not declared. Should it be static? arch/x86/kvm/mmu.c:1124:5: warning: symbol 'mmu_pages_next' was not declared. Should it be static? arch/x86/kvm/mmu.c:1144:6: warning: symbol 'mmu_pages_clear_parents' was not declared. Should it be static? arch/x86/kvm/x86.c:2037:5: warning: symbol 'kvm_read_guest_virt' was not declared. Should it be static? arch/x86/kvm/x86.c:2067:5: warning: symbol 'kvm_write_guest_virt' was not declared. Should it be static? virt/kvm/irq_comm.c:220:5: warning: symbol 'setup_routing_entry' was not declared. Should it be static? Signed-off-by: Hannes Eder <hannes@hanneseder.net> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: ia64: Fix the build errors due to lack of macros related to MSI.Xiantao Zhang2009-03-241-2/+0
| | | | | | | Include the newly introduced msidef.h to solve the build issues. Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: fix kvm_vm_ioctl_deassign_deviceWeidong Han2009-03-241-1/+1
| | | | | | | | | only need to set assigned_dev_id for deassignment, use match->flags to judge and deassign it. Acked-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Weidong Han <weidong.han@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Report IRQ injection status for MSI delivered interruptsGleb Natapov2009-03-241-5/+8
| | | | | | | | Return number of CPUs interrupt was successfully injected into or -1 if none. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Report IRQ injection status to userspace.Gleb Natapov2009-03-243-21/+45
| | | | | | | | | | | | IRQ injection status is either -1 (if there was no CPU found that should except the interrupt because IRQ was masked or ioapic was misconfigured or ...) or >= 0 in that case the number indicates to how many CPUs interrupt was injected. If the value is 0 it means that the interrupt was coalesced and probably should be reinjected. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: MMU: handle compound pages in kvm_is_mmio_pfnJoerg Roedel2009-03-241-2/+4
| | | | | | | | | | | | | | | The function kvm_is_mmio_pfn is called before put_page is called on a page by KVM. This is a problem when when this function is called on some struct page which is part of a compund page. It does not test the reserved flag of the compound page but of the struct page within the compount page. This is a problem when KVM works with hugepages allocated at boot time. These pages have the reserved bit set in all tail pages. Only the flag in the compount head is cleared. KVM would not put such a page which results in a memory leak. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Use irq routing API for MSISheng Yang2009-03-242-72/+76
| | | | | | | | | Merge MSI userspace interface with IRQ routing table. Notice the API have been changed, and using IRQ routing table would be the only interface kvm-userspace supported. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: make irq ack notifications aware of routing tableMarcelo Tosatti2009-03-242-8/+15
| | | | | | | | | | IRQ ack notifications assume an identity mapping between pin->gsi, which might not be the case with, for example, HPET. Translate before acking. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Acked-by: Gleb Natapov <gleb@redhat.com>
* KVM: Userspace controlled irq routingAvi Kivity2009-03-242-4/+200
| | | | | | | | | | | | | | | | | Currently KVM has a static routing from GSI numbers to interrupts (namely, 0-15 are mapped 1:1 to both PIC and IOAPIC, and 16:23 are mapped 1:1 to the IOAPIC). This is insufficient for several reasons: - HPET requires non 1:1 mapping for the timer interrupt - MSIs need a new method to assign interrupt numbers and dispatch them - ACPI APIC mode needs to be able to reassign the PCI LINK interrupts to the ioapics This patch implements an interrupt routing table (as a linked list, but this can be easily changed) and a userspace interface to replace the table. The routing table is initialized according to the current hardwired mapping. Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Interrupt mask notifiers for ioapicAvi Kivity2009-03-243-0/+33
| | | | | | | | | | Allow clients to request notifications when the guest masks or unmasks a particular irq line. This complements irq ack notifications, as the guest will not ack an irq line that is masked. Currently implemented for the ioapic only. Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Add support to disable MSI for assigned deviceSheng Yang2009-03-241-2/+16
| | | | | | | | | | | | | | MSI is always enabled by default for msi2intx=1. But if msi2intx=0, we have to disable MSI if guest require to do so. The patch also discard unnecessary msi2intx judgment if guest want to update MSI state. Notice KVM_DEV_IRQ_ASSIGN_MSI_ACTION is a mask which should cover all MSI related operations, though we only got one for now. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: New guest debug interfaceJan Kiszka2009-03-241-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | This rips out the support for KVM_DEBUG_GUEST and introduces a new IOCTL instead: KVM_SET_GUEST_DEBUG. The IOCTL payload consists of a generic part, controlling the "main switch" and the single-step feature. The arch specific part adds an x86 interface for intercepting both types of debug exceptions separately and re-injecting them when the host was not interested. Moveover, the foundation for guest debugging via debug registers is layed. To signal breakpoint events properly back to userland, an arch-specific data block is now returned along KVM_EXIT_DEBUG. For x86, the arch block contains the PC, the debug exception, and relevant debug registers to tell debug events properly apart. The availability of this new interface is signaled by KVM_CAP_SET_GUEST_DEBUG. Empty stubs for not yet supported archs are provided. Note that both SVM and VTX are supported, but only the latter was tested yet. Based on the experience with all those VTX corner case, I would be fairly surprised if SVM will work out of the box. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Fix assigned devices circular locking dependencyMark McLoughlin2009-02-152-4/+5
| | | | | | | | | | | kvm->slots_lock is outer to kvm->lock, so take slots_lock in kvm_vm_ioctl_assign_device() before taking kvm->lock, rather than taking it in kvm_iommu_map_memslots(). Cc: stable@kernel.org Signed-off-by: Mark McLoughlin <markmc@redhat.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Fix INTx for device assignmentSheng Yang2009-02-151-2/+2
| | | | | | | Missing buckets and wrong parameter for free_irq() Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Fix racy in kvm_free_assigned_irqSheng Yang2009-02-151-8/+19
| | | | | | | | | | | | | | | | | | | | | | In the past, kvm_get_kvm() and kvm_put_kvm() was called in assigned device irq handler and interrupt_work, in order to prevent cancel_work_sync() in kvm_free_assigned_irq got a illegal state when waiting for interrupt_work done. But it's tricky and still got two problems: 1. A bug ignored two conditions that cancel_work_sync() would return true result in a additional kvm_put_kvm(). 2. If interrupt type is MSI, we would got a window between cancel_work_sync() and free_irq(), which interrupt would be injected again... This patch discard the reference count used for irq handler and interrupt_work, and ensure the legal state by moving the free function at the very beginning of kvm_destroy_vm(). And the patch fix the second bug by disable irq before cancel_work_sync(), which may result in nested disable of irq but OK for we are going to free it. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Add kvm_arch_sync_events to sync with asynchronize eventsSheng Yang2009-02-151-0/+1
| | | | | | | | | | | | | kvm_arch_sync_events is introduced to quiet down all other events may happen contemporary with VM destroy process, like IRQ handler and work struct for assigned device. For kvm_arch_sync_events is called at the very beginning of kvm_destroy_vm(), so the state of KVM here is legal and can provide a environment to quiet down other events. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: mmu_notifiers release methodMarcelo Tosatti2009-02-151-0/+8
| | | | | | | | | | | | | | | | | | | The destructor for huge pages uses the backing inode for adjusting hugetlbfs accounting. Hugepage mappings are destroyed by exit_mmap, after mmu_notifier_release, so there are no notifications through unmap_hugepage_range at this point. The hugetlbfs inode can be freed with pages backed by it referenced by the shadow. When the shadow releases its reference, the huge page destructor will access a now freed inode. Implement the release operation for kvm mmu notifiers to release page refs before the hugetlbfs inode is gone. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* kvm/iommu: fix compile warningJoerg Roedel2009-01-031-1/+1
| | | | | | | This fixes a compile warning about a variable thats maybe used uninitialized in the function. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* KVM: change KVM to use IOMMU APIJoerg Roedel2009-01-032-25/+22
| | | | Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* KVM: rename vtd.c to iommu.cJoerg Roedel2009-01-031-0/+0
| | | | | | | | | Impact: file renamed The code in the vtd.c file can be reused for other IOMMUs as well. So rename it to make it clear that it handle more than VT-d. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* Deassign device in kvm_free_assgined_deviceWeidong Han2009-01-032-10/+1
| | | | | | | In kvm_iommu_unmap_memslots(), assigned_dev_head is already empty. Signed-off-by: Weidong Han <weidong.han@intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* KVM: support device deassignmentWeidong Han2009-01-032-0/+66
| | | | | | | Support device deassignment, it can be used in device hotplug. Signed-off-by: Weidong Han <weidong.han@intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* KVM: use the new intel iommu APIsWeidong Han2009-01-032-44/+61
| | | | | | | | | intel iommu APIs are updated, use the new APIs. In addition, change kvm_iommu_map_guest() to just create the domain, let kvm_iommu_assign_device() assign device. Signed-off-by: Weidong Han <weidong.han@intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* KVM: fix handling of ACK from shared guest IRQMark McLoughlin2008-12-311-1/+14
| | | | | | | | | | | | | | | | | | | If an assigned device shares a guest irq with an emulated device then we currently interpret an ack generated by the emulated device as originating from the assigned device leading to e.g. "Unbalanced enable for IRQ 4347" from the enable_irq() in kvm_assigned_dev_ack_irq(). The fix is fairly simple - don't enable the physical device irq unless it was previously disabled. Of course, this can still lead to a situation where a non-assigned device ACK can cause the physical device irq to be reenabled before the device was serviced. However, being level sensitive, the interrupt will merely be regenerated. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Consolidate userspace memory capability reporting into common codeAvi Kivity2008-12-311-0/+1
| | | | Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Advertise the bug in memory region destruction as fixedAvi Kivity2008-12-311-1/+12
| | | | | | Userspace might need to act differently. Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: use cpumask_var_t for cpus_hardware_enabledRusty Russell2008-12-311-6/+14
| | | | | | | | This changes cpus_hardware_enabled from a cpumask_t to a cpumask_var_t: equivalent for CONFIG_CPUMASKS_OFFSTACK=n, otherwise dynamically allocated. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: use modern cpumask primitives, no cpumask_t on stackRusty Russell2008-12-311-9/+14
| | | | | | | | | | | | | | | | We're getting rid on on-stack cpumasks for large NR_CPUS. 1) Use cpumask_var_t/alloc_cpumask_var. 2) smp_call_function_mask -> smp_call_function_many 3) cpus_clear, cpus_empty, cpu_set -> cpumask_clear, cpumask_empty, cpumask_set_cpu. This actually generates slightly smaller code than the old one with CONFIG_CPUMASKS_OFFSTACK=n. (gcc knows that cpus cannot be NULL in that case, where cpumask_var_t is cpumask_t[1]). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Extract core of kvm_flush_remote_tlbs/kvm_reload_remote_mmusRusty Russell2008-12-311-29/+15
| | | | | | | | | | Avi said: > Wow, code duplication from Rusty. Things must be bad. Something about glass houses comes to mind. But instead, a patch. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: set owner of cpu and vm file operationsChristian Borntraeger2008-12-311-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a race between a "close of the file descriptors" and module unload in the kvm module. You can easily trigger this problem by applying this debug patch: >--- kvm.orig/virt/kvm/kvm_main.c >+++ kvm/virt/kvm/kvm_main.c >@@ -648,10 +648,14 @@ void kvm_free_physmem(struct kvm *kvm) > kvm_free_physmem_slot(&kvm->memslots[i], NULL); > } > >+#include <linux/delay.h> > static void kvm_destroy_vm(struct kvm *kvm) > { > struct mm_struct *mm = kvm->mm; > >+ printk("off1\n"); >+ msleep(5000); >+ printk("off2\n"); > spin_lock(&kvm_lock); > list_del(&kvm->vm_list); > spin_unlock(&kvm_lock); and killing the userspace, followed by an rmmod. The problem is that kvm_destroy_vm can run while the module count is 0. That means, you can remove the module while kvm_destroy_vm is running. But kvm_destroy_vm is part of the module text. This causes a kerneloops. The race exists without the msleep but is much harder to trigger. This patch requires the fix for anon_inodes (anon_inodes: use fops->owner for module refcount). With this patch, we can set the owner of all anonymous KVM inodes file operations. The VFS will then control the KVM module refcount as long as there is an open file. kvm_destroy_vm will be called by the release function of the last closed file - before the VFS drops the module refcount. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Really remove a slot when a user ask us soGlauber Costa2008-12-311-1/+4
| | | | | | | | | | | | | | | | | Right now, KVM does not remove a slot when we do a register ioctl for size 0 (would be the expected behaviour). Instead, we only mark it as empty, but keep all bitmaps and allocated data structures present. It completely nullifies our chances of reusing that same slot again for mapping a different piece of memory. In this patch, we destroy rmaps, and vfree() the pointers that used to hold the dirty bitmap, rmap and lpage_info structures. Signed-off-by: Glauber Costa <glommer@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: split out kvm_free_assigned_irq()Mark McLoughlin2008-12-311-7/+22
| | | | | | | | Split out the logic corresponding to undoing assign_irq() and clean it up a bit. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: add KVM_USERSPACE_IRQ_SOURCE_ID assertionsMark McLoughlin2008-12-311-4/+10
| | | | | | | | | | | Make sure kvm_request_irq_source_id() never returns KVM_USERSPACE_IRQ_SOURCE_ID. Likewise, check that kvm_free_irq_source_id() never accepts KVM_USERSPACE_IRQ_SOURCE_ID. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: don't free an unallocated irq source idMark McLoughlin2008-12-311-2/+5
| | | | | | | | Set assigned_dev->irq_source_id to -1 so that we can avoid freeing a source ID which we never allocated. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: make kvm_unregister_irq_ack_notifier() safeMark McLoughlin2008-12-311-3/+1
| | | | | | | | | | | | | | | | | We never pass a NULL notifier pointer here, but we may well pass a notifier struct which hasn't previously been registered. Guard against this by using hlist_del_init() which will not do anything if the node hasn't been added to the list and, when removing the node, will ensure that a subsequent call to hlist_del_init() will be fine too. Fixes an oops seen when an assigned device is freed before and IRQ is assigned to it. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: remove the IRQ ACK notifier assertionsMark McLoughlin2008-12-311-3/+0
| | | | | | | | | | | | | We will obviously never pass a NULL struct kvm_irq_ack_notifier* to this functions. They are always embedded in the assigned device structure, so the assertion add nothing. The irqchip_in_kernel() assertion is very out of place - clearly this little abstraction needs to know nothing about the upper layer details. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: fix sparse warningHannes Eder2008-12-311-1/+1
| | | | | | | | | Impact: make global function static virt/kvm/kvm_main.c:85:6: warning: symbol 'kvm_rebooting' was not declared. Should it be static? Signed-off-by: Hannes Eder <hannes@hanneseder.net> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Prevent trace call into unloaded module textWu Fengguang2008-12-311-0/+1
| | | | | | | | Add marker_synchronize_unregister() before module unloading. This prevents possible trace calls into unloaded module text. Signed-off-by: Wu Fengguang <wfg@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: MSI to INTx translateSheng Yang2008-12-311-16/+54
| | | | | | | | | | | | | | | | | | Now we use MSI as default one, and translate MSI to INTx when guest need INTx rather than MSI. For legacy device, we provide support for non-sharing host IRQ. Provide a parameter msi2intx for this method. The value is true by default in x86 architecture. We can't guarantee this mode can work on every device, but for most of us tested, it works. If your device encounter some trouble with this mode, you can try set msi2intx modules parameter to 0. If the device is OK with msi2intx=0, then please report it to KVM mailing list or me. We may prepare a blacklist for the device that can't work in this mode. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Enable MSI for device assignmentSheng Yang2008-12-311-6/+75
| | | | | | | | | | | | | We enable guest MSI and host MSI support in this patch. The userspace want to enable MSI should set KVM_DEV_IRQ_ASSIGN_ENABLE_MSI in the assigned_irq's flag. Function would return -ENOTTY if can't enable MSI, userspace shouldn't set MSI Enable bit when KVM_ASSIGN_IRQ return -ENOTTY with KVM_DEV_IRQ_ASSIGN_ENABLE_MSI. Userspace can tell the support of MSI device from #ifdef KVM_CAP_DEVICE_MSI. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Add assigned_device_msi_dispatch()Sheng Yang2008-12-311-0/+55
| | | | | | | | The function is used to dispatch MSI to lapic according to MSI message address and message data. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Export ioapic_get_delivery_bitmaskSheng Yang2008-12-312-3/+6
| | | | | | | It would be used for MSI in device assignment, for MSI dispatch. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Clean up assigned_device_update_irqSheng Yang2008-12-311-6/+4
| | | | | Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Replace irq_requested with more generic irq_requested_typeSheng Yang2008-12-311-4/+5
| | | | | | | | Separate guest irq type and host irq type, for we can support guest using INTx with host using MSI (but not opposite combination). Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Separate update irq to a single functionSheng Yang2008-12-311-30/+38
| | | | | | | | Separate INTx enabling part to a independence function, so that we can add MSI enabling part easily. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Move ack notifier register and IRQ sourcd ID requestSheng Yang2008-12-311-11/+19
| | | | | | | | Distinguish common part for device assignment and INTx part, perparing for refactor later. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Fix kernel allocated memory slotSheng Yang2008-12-311-1/+1
| | | | | | | | | Commit 7fd49de9773fdcb7b75e823b21c1c5dc1e218c14 "KVM: ensure that memslot userspace addresses are page-aligned" broke kernel space allocated memory slot, for the userspace_addr is invalid. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>