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2020-01-27KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF attacksMarios Pomonis1-1/+5
This fixes a Spectre-v1/L1TF vulnerability in picdev_write(). It replaces index computations based on the (attacked-controlled) port number with constants through a minor refactoring. Fixes: 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Cc: stable@vger.kernel.org Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-20kvm: x86: Add memcg accounting to KVM allocationsBen Gardon1-1/+1
There are many KVM kernel memory allocations which are tied to the life of the VM process and should be charged to the VM process's cgroup. If the allocations aren't tied to the process, the OOM killer will not know that killing the process will free the associated kernel memory. Add __GFP_ACCOUNT flags to many of the allocations which are not yet being charged to the VM process's cgroup. Tested: Ran all kvm-unit-tests on a 64 bit Haswell machine, the patch introduced no new failures. Ran a kernel memory accounting test which creates a VM to touch memory and then checks that the kernel memory allocated for the process is within certain bounds. With this patch we account for much more of the vmalloc and slab memory allocated for the VM. There remain a few allocations which should be charged to the VM's cgroup but are not. In x86, they include: vcpu->arch.pio_data There allocations are unaccounted in this patch because they are mapped to userspace, and accounting them to a cgroup causes problems. This should be addressed in a future patch. Signed-off-by: Ben Gardon <bgardon@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-12KVM: x86: simplify pic_ioport_read()David Hildenbrand1-6/+3
Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12KVM: x86: set data directly in picdev_read()David Hildenbrand1-4/+3
Now it looks almost as picdev_write(). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12KVM: x86: drop picdev_in_range()David Hildenbrand1-23/+12
We already have the exact same checks a couple of lines below. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12KVM: x86: make kvm_pic_reset() staticDavid Hildenbrand1-1/+1
Not used outside of i8259.c, so let's make it static. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12KVM: x86: simplify pic_unlock()David Hildenbrand1-9/+4
We can easily compact this code and get rid of one local variable. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12KVM: x86: push usage of slots_lock downDavid Hildenbrand1-0/+2
Let's just move it to the place where it is actually needed. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12KVM: x86: get rid of pic_irqchip()David Hildenbrand1-2/+2
It seemed like a nice idea to encapsulate access to kvm->arch.vpic. But as the usage is already mixed, internal locks are taken outside of i8259.c and grepping for "vpic" only is much easier, let's just get rid of pic_irqchip(). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-23KVM: x86: check existance before destroyPeter Xu1-0/+3
Mostly used for split irqchip mode. In that case, these two things are not inited at all, so no need to release. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-01-09KVM: x86: make pic setup code look like ioapic setupRadim Krčmář1-5/+11
We don't treat kvm->arch.vpic specially anymore, so the setup can look like ioapic. This gets a bit more information out of return values. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-30KVM: x86: clean/fix memory barriers in irqchip_in_kernelPaolo Bonzini1-10/+5
The memory barriers are trying to protect against concurrent RCU-based interrupt injection, but the IRQ routing table is not valid at the time kvm->arch.vpic is written. Fix this by writing kvm->arch.vpic last. kvm_destroy_pic then need not set kvm->arch.vpic to NULL; modify it to take a struct kvm_pic* and reuse it if the IOAPIC creation fails. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-07Merge tag 'kvm-arm-for-4.1' of ↵Paolo Bonzini1-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into 'kvm-next' KVM/ARM changes for v4.1: - fixes for live migration - irqfd support - kvm-io-bus & vgic rework to enable ioeventfd - page ageing for stage-2 translation - various cleanups
2015-03-30kvm: x86: i8259: return initialized data on invalid-size readPetr Matousek1-0/+1
If data is read from PIC with invalid access size, the return data stays uninitialized even though success is returned. Fix this by always initializing the data. Signed-off-by: Petr Matousek <pmatouse@redhat.com> Reported-by: Nadav Amit <nadav.amit@gmail.com> Message-Id: <20150311111609.GG8544@dhcp-25-225.brq.redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-26KVM: Redesign kvm_io_bus_ API to pass VCPU structure to the callbacks.Nikolay Nikolaev1-6/+6
This is needed in e.g. ARM vGIC emulation, where the MMIO handling depends on the VCPU that does the access. Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-13KVM: inject ExtINT interrupt before APIC interruptsGleb Natapov1-0/+2
According to Intel SDM Volume 3 Section 10.8.1 "Interrupt Handling with the Pentium 4 and Intel Xeon Processors" and Section 10.8.2 "Interrupt Handling with the P6 Family and Pentium Processors" ExtINT interrupts are sent directly to the processor core for handling. Currently KVM checks APIC before it considers ExtINT interrupts for injection which is backwards from the spec. Make code behave according to the SDM. Signed-off-by: Gleb Natapov <gleb@redhat.com> Acked-by: "Zhang, Yang Z" <yang.z.zhang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-09-04KVM: cleanup pic resetGleb Natapov1-41/+11
kvm_pic_reset() is not used anywhere. Move reset logic from pic_ioport_write() there. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-14KVM: x86: drop parameter validation in ioapic/picMichael S. Tsirkin1-9/+9
We validate irq pin number when routing is setup, so code handling illegal irq # in pic and ioapic on each injection is never called. Drop it, replace with BUG_ON to catch out of bounds access bugs. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-07-26KVM: PIC: call ack notifiers for irqs that are dropped form irrGleb Natapov1-0/+17
After commit 242ec97c358256 PIT interrupts are no longer delivered after PIC reset. It happens because PIT injects interrupt only if previous one was acked, but since on PIC reset it is dropped from irr it will never be delivered and hence acknowledged. Fix that by calling ack notifier on PIC reset. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-20KVM: fix race with level interruptsMichael S. Tsirkin1-3/+14
When more than 1 source id is in use for the same GSI, we have the following race related to handling irq_states race: CPU 0 clears bit 0. CPU 0 read irq_state as 0. CPU 1 sets level to 1. CPU 1 calls kvm_ioapic_set_irq(1). CPU 0 calls kvm_ioapic_set_irq(0). Now ioapic thinks the level is 0 but irq_state is not 0. Fix by performing all irq_states bitmap handling under pic/ioapic lock. This also removes the need for atomics with irq_states handling. Reported-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-03-05KVM: x86: reset edge sense circuit of i8259 on initGleb Natapov1-0/+1
The spec says that during initialization "The edge sense circuit is reset which means that following initialization an interrupt request (IR) input must make a low-to-high transition to generate an interrupt", but currently if edge triggered interrupt is in IRR it is delivered after i8259 initialization. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27KVM: drop bsp_vcpu pointer from kvm structGleb Natapov1-8/+16
Drop bsp_vcpu pointer from kvm struct since its only use is incorrect anyway. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-09-25KVM: Clean up and extend rate-limited outputJan Kiszka1-7/+8
The use of printk_ratelimit is discouraged, replace it with pr*_ratelimited or __ratelimit. While at it, convert remaining guest-triggerable printks to rate-limited variants. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-09-25KVM: Intelligent device lookup on I/O busSasha Levin1-19/+89
Currently the method of dealing with an IO operation on a bus (PIO/MMIO) is to call the read or write callback for each device registered on the bus until we find a device which handles it. Since the number of devices on a bus can be significant due to ioeventfds and coalesced MMIO zones, this leads to a lot of overhead on each IO operation. Instead of registering devices, we now register ranges which points to a device. Lookup is done using an efficient bsearch instead of a linear search. Performance test was conducted by comparing exit count per second with 200 ioeventfds created on one byte and the guest is trying to access a different byte continuously (triggering usermode exits). Before the patch the guest has achieved 259k exits per second, after the patch the guest does 274k exits per second. Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17KVM: remove isr_ack logic from PICGleb Natapov1-23/+2
isr_ack logic was added by e48258009d to avoid unnecessary IPIs. Back then it made sense, but now the code checks that vcpu is ready to accept interrupt before sending IPI, so this logic is no longer needed. The patch removes it. Fixes a regression with Debian/Hurd. Signed-off-by: Gleb Natapov <gleb@redhat.com> Reported-and-tested-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-02KVM: i8259: initialize isr_ackAvi Kivity1-0/+2
isr_ack is never initialized. So, until the first PIC reset, interrupts may fail to be injected. This can cause Windows XP to fail to boot, as reported in the fallout from the fix to https://bugzilla.kernel.org/show_bug.cgi?id=21962. Reported-and-tested-by: Nicolas Prochazka <prochazka.nicolas@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24KVM: fix typo in copyright noticeNicolas Kaiser1-1/+1
Fix typo in copyright notice. Signed-off-by: Nicolas Kaiser <nikai@nikai.net> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24KVM: Convert PIC lock from raw spinlock to ordinary spinlockAvi Kivity1-3/+3
The PIC code used to be called from preempt_disable() context, which wasn't very good for PREEMPT_RT. That is no longer the case, so move back from raw_spinlock_t to spinlock_t. Signed-off-by: Avi Kivity <avi@redhat.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24KVM: Check for pending events before attempting injectionAvi Kivity1-0/+1
Instead of blindly attempting to inject an event before each guest entry, check for a possible event first in vcpu->requests. Sites that can trigger event injection are modified to set KVM_REQ_EVENT: - interrupt, nmi window opening - ppr updates - i8259 output changes - local apic irr changes - rflags updates - gif flag set - event set on exit This improves non-injecting entry performance, and sets the stage for non-atomic injection. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24KVM: i8259: Make ICW1 conform to specAvi Kivity1-6/+10
ICW is not a full reset, instead it resets a limited number of registers in the PIC. Change ICW1 emulation to only reset those registers. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-09-08KVM: fix i8259 oops when no vcpus are onlineAvi Kivity1-0/+3
If there are no vcpus, found will be NULL. Check before doing anything with it. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-02KVM: x86: Call mask notifiers from picGleb Natapov1-1/+11
If pit delivers interrupt while pic is masking it OS will never do EOI and ack notifier will not be called so when pit will be unmasked no pit interrupts will be delivered any more. Calling mask notifiers solves this issue. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01KVM: Search the LAPIC's for one that will accept a PIC interruptChris Lalancette1-4/+13
Older versions of 32-bit linux have a "Checking 'hlt' instruction" test where they repeatedly call the 'hlt' instruction, and then expect a timer interrupt to kick the CPU out of halt. This happens before any LAPIC or IOAPIC setup happens, which means that all of the APIC's are in virtual wire mode at this point. Unfortunately, the current implementation of virtual wire mode is hardcoded to only kick the BSP, so if a crash+kexec occurs on a different vcpu, it will never get kicked. This patch makes pic_unlock() do the equivalent of kvm_irq_delivery_to_apic() for the IOAPIC code. That is, it runs through all of the vcpus looking for one that is in virtual wire mode. In the normal case where LAPICs and IOAPICs are configured, this won't be used at all. In the bootstrap phase of a modern OS, before the LAPICs and IOAPICs are configured, this will have exactly the same behavior as today; VCPU0 is always looked at first, so it will always get out of the loop after the first iteration. This will only go through the loop more than once during a kexec/kdump, in which case it will only do it a few times until the kexec'ed kernel programs the LAPIC and IOAPIC. Signed-off-by: Chris Lalancette <clalance@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: i8259: simplify pic_irq_request() calling sequenceAvi Kivity1-4/+1
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: i8259: reduce excessive abstraction for pic_irq_request()Avi Kivity1-10/+7
Part of the i8259 code pretends it isn't part of kvm, but we know better. Reduce excessive abstraction, eliminating callbacks and void pointers. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: Update Red Hat copyrightsAvi Kivity1-0/+1
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25KVM: x86: Kick VCPU outside PIC lock againJan Kiszka1-15/+38
This restores the deferred VCPU kicking before 956f97cf. We need this over -rt as wake_up* requires non-atomic context in this configuration. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-01KVM: Convert i8254/i8259 locks to raw_spinlocksThomas Gleixner1-15/+16
The i8254/i8259 locks need to be real spinlocks on preempt-rt. Convert them to raw_spinlock. No change for !RT kernels. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01KVM: cleanup the failure path of KVM_CREATE_IRQCHIP ioctrlWei Yongjun1-0/+11
If we fail to init ioapic device or the fail to setup the default irq routing, the device register by kvm_create_pic() and kvm_ioapic_init() remain unregister. This patch fixed to do this. Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01KVM: convert slots_lock to a mutexMarcelo Tosatti1-2/+2
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01KVM: convert io_bus to SRCUMarcelo Tosatti1-1/+3
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-12-03KVM: Move IO APIC to its own lockGleb Natapov1-6/+16
The allows removal of irq_lock from the injection path. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03KVM: Call pic_clear_isr() on pic reset to reuse logic thereGleb Natapov1-13/+9
Also move call of ack notifiers after pic state change. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Replace pic_lock()/pic_unlock() with direct call to spinlock functionsGleb Natapov1-24/+12
They are not doing anything else now. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Call ack notifiers from PIC when guest OS acks an IRQ.Gleb Natapov1-14/+4
Currently they are called when irq vector is been delivered. Calling ack notifiers at this point is wrong. Device assignment ack notifier enables host interrupts, but guest not yet had a chance to clear interrupt condition in a device. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Call kvm_vcpu_kick() inside pic spinlockGleb Natapov1-9/+1
d5ecfdd25 moved it out because back than it was impossible to call it inside spinlock. This restriction no longer exists. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: make io_bus interface more robustGregory Haskins1-1/+8
Today kvm_io_bus_regsiter_dev() returns void and will internally BUG_ON if it fails. We want to create dynamic MMIO/PIO entries driven from userspace later in the series, so we need to enhance the code to be more robust with the following changes: 1) Add a return value to the registration function 2) Fix up all the callsites to check the return code, handle any failures, and percolate the error up to the caller. 3) Add an unregister function that collapses holes in the array Signed-off-by: Gregory Haskins <ghaskins@novell.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Add trace points in irqchip codeGleb Natapov1-0/+3
Add tracepoint in msi/ioapic/pic set_irq() functions, in IPI sending and in the point where IRQ is placed into apic's IRR. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: remove in_range from io devicesMichael S. Tsirkin1-8/+12
This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write functions. in_range now becomes unused so it is removed from device ops in favor of read/write callbacks performing range checks internally. This allows aliasing (mostly for in-kernel virtio), as well as better error handling by making it possible to pass errors up to userspace. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>