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2009-10-04KVM: s390: fix memsize >= 4GChristian Borntraeger
commit 628eb9b8a8f3 KVM: s390: streamline memslot handling introduced kvm_s390_vcpu_get_memsize. This broke guests >=4G, since this function returned an int. This patch changes the return value to a long. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-21trivial: remove unnecessary semicolonsJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-10KVM: Reduce runnability interface with arch support codeGleb Natapov
Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from interface between general code and arch code. kvm_arch_vcpu_runnable() checks for interrupts instead. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: remove old KVMTRACE support codeMarcelo Tosatti
Return EOPNOTSUPP for KVM_TRACE_ENABLE/PAUSE/DISABLE ioctls. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Use macro to iterate over vcpus.Gleb Natapov
[christian: remove unused variables on s390] Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: s390: streamline memslot handlingChristian Ehrhardt
This patch relocates the variables kvm-s390 uses to track guest mem addr/size. As discussed dropping the variables at struct kvm_arch level allows to use the common vcpu->request based mechanism to reload guest memory if e.g. changes via set_memory_region. The kick mechanism introduced in this series is used to ensure running vcpus leave guest state to catch the update. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: s390: fix signal handlingChristian Ehrhardt
If signal pending is true we exit without updating kvm_run, userspace currently just does nothing and jumps to kvm_run again. Since we did not set an exit_reason we might end up with a random one (whatever was the last exit). Therefore it was possible to e.g. jump to the psw position the last real interruption set. Setting the INTR exit reason ensures that no old psw data is swapped in on reentry. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: s390: infrastructure to kick vcpus out of guest stateChristian Ehrhardt
To ensure vcpu's come out of guest context in certain cases this patch adds a s390 specific way to kick them out of guest context. Currently it kicks them out to rerun the vcpu_run path in the s390 code, but the mechanism itself is expandable and with a new flag we could also add e.g. kicks to userspace etc. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Move common KVM Kconfig items to new file virt/kvm/KconfigAvi Kivity
Reduce Kconfig code duplication. Signed-off-by: Avi Kivity <avi@redhat.com>
2009-08-09Merge branch 'kvm-updates/2.6.31' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
* 'kvm-updates/2.6.31' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: Avoid redelivery of edge interrupt before next edge KVM: MMU: limit rmap chain length KVM: ia64: fix build failures due to ia64/unsigned long mismatches KVM: Make KVM_HPAGES_PER_HPAGE unsigned long to avoid build error on powerpc KVM: fix ack not being delivered when msi present KVM: s390: fix wait_queue handling KVM: VMX: Fix locking imbalance on emulation failure KVM: VMX: Fix locking order in handle_invalid_guest_state KVM: MMU: handle n_free_mmu_pages > n_alloc_mmu_pages in kvm_mmu_change_mmu_pages KVM: SVM: force new asid on vcpu migration KVM: x86: verify MTRR/PAT validity KVM: PIT: fix kpit_elapsed division by zero KVM: Fix KVM_GET_MSR_INDEX_LIST
2009-08-07[S390] KVM: Read buffer overflowRoel Kluin
Check whether index is within bounds before testing the element. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-08-05KVM: s390: fix wait_queue handlingChristian Borntraeger
There are two waitqueues in kvm for wait handling: vcpu->wq for virt/kvm/kvm_main.c and vpcu->arch.local_int.wq for the s390 specific wait code. the wait handling in kvm_s390_handle_wait was broken by using different wait_queues for add_wait queue and remove_wait_queue. There are two options to fix the problem: o move all the s390 specific code to vcpu->wq and remove vcpu->arch.local_int.wq o move all the s390 specific code to vcpu->arch.local_int.wq This patch chooses the 2nd variant for two reasons: o s390 does not use kvm_vcpu_block but implements its own enabled wait handling. Having a separate wait_queue make it clear, that our wait mechanism is different o the patch is much smaller Report-by: Julia Lawall <julia@diku.dk> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-28KVM: s390: Allow stfle instruction in the guestChristian Borntraeger
2.6.31-rc introduced an architecture level set checker based on facility bits. e.g. if the kernel is compiled to run only on z9, several facility bits are checked very early and the kernel refuses to boot if a z9 specific facility is missing. Until now kvm on s390 did not implement the store facility extended (STFLE) instruction. A 2.6.31-rc kernel that was compiled for z9 or higher did not boot in kvm. This patch implements stfle. This patch should go in before 2.6.31. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-12[S390] uaccess: use might_fault() instead of might_sleep()Heiko Carstens
Adds more checking in case lockdep is turned on. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-10KVM: s390: Verify memory in kvm runCarsten Otte
This check verifies that the guest we're trying to run in KVM_RUN has some memory assigned to it. It enters an endless exception loop if this is not the case. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: Sanity check on validity interceptCarsten Otte
This patch adds a sanity check for the content of the guest prefix register content before faulting in the cpu lowcore that it refers to. The guest might end up in an endless loop where SIE complains about missing lowcore with incorrect content of the prefix register without this fix. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: Unlink vcpu on destroy - v2Carsten Otte
This patch makes sure we do unlink a vcpu's sie control block from the system control area in kvm_arch_vcpu_destroy. This prevents illegal accesses to the sie control block from other virtual cpus after free. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: optimize float int lock: spin_lock_bh --> spin_lockChristian Borntraeger
The floating interrupt lock is only taken in process context. We can replace all spin_lock_bh with standard spin_lock calls. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: use hrtimer for clock wakeup from idle - v2Christian Borntraeger
This patch reworks the s390 clock comparator wakeup to hrtimer. The clock comparator is a per-cpu value that is compared against the TOD clock. If ckc <= TOD an external interrupt 1004 is triggered. Since the clock comparator and the TOD clock have a much higher resolution than jiffies we should use hrtimers to trigger the wakeup. This speeds up guest nanosleep for small values. Since hrtimers callbacks run in hard-irq context, I added a tasklet to do the actual work with enabled interrupts. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: Fix memory slot versus run - v3Carsten Otte
This patch fixes an incorrectness in the kvm backend for s390. In case virtual cpus are being created before the corresponding memory slot is being registered, we need to update the sie control blocks for the virtual cpus. *updates in v3* In consideration of the s390 memslot constraints locking was changed to trylock. These locks should never be held, as vcpu's can't run without the single memslot we just assign when running this code. To ensure this never deadlocks in case other code changes the code uses trylocks and bail out if it can't get all locks. Additionally most of the discussed special conditions for s390 like only one memslot and no user_alloc are now checked for validity in kvm_arch_set_memory_region. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: Fix interrupt unhalting a vcpu when it shouldn'tGleb Natapov
kvm_vcpu_block() unhalts vpu on an interrupt/timer without checking if interrupt window is actually opened. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-26Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6Linus Torvalds
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (81 commits) [S390] remove duplicated #includes [S390] cpumask: use mm_cpumask() wrapper [S390] cpumask: Use accessors code. [S390] cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits. [S390] cpumask: remove cpu_coregroup_map [S390] fix clock comparator save area usage [S390] Add hwcap flag for the etf3 enhancement facility [S390] Ensure that ipl panic notifier is called late. [S390] fix dfp elf hwcap/facility bit detection [S390] smp: perform initial cpu reset before starting a cpu [S390] smp: fix memory leak on __cpu_up [S390] ipl: Improve checking logic and remove switch defaults. [S390] s390dbf: Remove needless check for NULL pointer. [S390] s390dbf: Remove redundant initilizations. [S390] use kzfree() [S390] BUG to BUG_ON changes [S390] zfcpdump: Prevent zcore from beeing built as a kernel module. [S390] Use csum_partial in checksum.h [S390] cleanup lowcore.h [S390] eliminate ipl_device from lowcore ...
2009-03-26[S390] split/move machine check handler codeHeiko Carstens
Split machine check handler code and move it to cio and kernel code where it belongs to. No functional change. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] Fix hypervisor detection for KVMChristian Borntraeger
Currently we use the cpuid (via STIDP instruction) to recognize LPAR, z/VM and KVM. The architecture states, that bit 0-7 of STIDP returns all zero, and if STIDP is executed in a virtual machine, the VM operating system will replace bits 0-7 with FF. KVM should not use FE to distinguish z/VM from KVM for interested guests. The proper way to detect the hypervisor is the STSI (Store System Information) instruction, which return information about the hypervisors via function code 3, selector1=2, selector2=2. This patch changes the detection routine of Linux to use STSI instead of STIDP. This detection is earlier than bootmem, we have to use a static buffer. Since STSI expects a 4kb block (4kb aligned) this patch also changes the init.data alignment for s390. As this section will be freed during boot, this should be no problem. Patch is tested with LPAR, z/VM, KVM on LPAR, and KVM under z/VM. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-24KVM: s390: Fix SIGP set prefix ioctlChristian Borntraeger
This patch fixes the SET PREFIX interrupt if triggered by userspace. Until now, it was not necessary, but life migration will need it. In addition, it helped me creating SMP support for my kvm_crashme tool (lets kvm execute random guest memory content). Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: s390: Fix problem state check for b2 interceptsChristian Borntraeger
The kernel handles some priviledged instruction exits. While I was unable to trigger such an exit from guest userspace, the code should check for supervisor state before emulating a priviledged instruction. I also renamed kvm_s390_handle_priv to kvm_s390_handle_b2. After all there are non priviledged b2 instructions like stck (store clock). Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: s390: Fix printk on SIGP set archChristian Borntraeger
KVM on s390 does not support the ESA/390 architecture. We refuse to change the architecture mode and print a warning. This patch removes the printk for several reasons: o A malicious guest can flood host dmesg o The old message had no newline o there is no connection between the message and the failing guest This patch simply removes the printk. We already set the condition code to 3 - the guest knows that something went wrong. Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: Add CONFIG_HAVE_KVM_IRQCHIPAvi Kivity
Two KVM archs support irqchips and two don't. Add a Kconfig item to make selecting between the two models easier. Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: New guest debug interfaceJan Kiszka
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>
2009-02-15KVM: Add kvm_arch_sync_events to sync with asynchronize eventsSheng Yang
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>
2009-01-09[S390] Use unsigned long long for u64 on 64bit.Heiko Carstens
As requested by Andrew. Same as what sparc did. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31KVM: Consolidate userspace memory capability reporting into common codeAvi Kivity
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31KVM: s390: Fix memory leak of vcpu->runChristian Borntraeger
The s390 backend of kvm never calls kvm_vcpu_uninit. This causes a memory leak of vcpu->run pages. Lets call kvm_vcpu_uninit in kvm_arch_vcpu_destroy to free the vcpu->run. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31KVM: s390: Fix refcounting and allow module unloadChristian Borntraeger
Currently it is impossible to unload the kvm module on s390. This patch fixes kvm_arch_destroy_vm to release all cpus. This make it possible to unload the module. In addition we stop messing with the module refcount in arch code. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-11-23KVM: s390: Fix problem state handling in guest sigp handlerChristian Borntraeger
We can get an exit for instructions starting with 0xae, even if the guest is in userspace. Lets make sure, that the signal processor handler is only called in guest supervisor mode. Otherwise, send a program check. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15KVM: s390: Make facility bits future-proofChristian Borntraeger
Heiko Carstens pointed out, that its safer to activate working facilities instead of disabling problematic facilities. The new code uses the host facility bits and masks it with known good ones. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-31KVM: s390: Fix kvm on IBM System z10Christian Borntraeger
The z10 system supports large pages, kvm-s390 doesnt. Make sure that we dont advertise large pages to avoid the guest crashing as soon as the guest kernel activates DAT. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-27KVM: s390: Fix possible host kernel bug on lctl(g) handlingChristian Borntraeger
The lctl(g) instructions require a specific alignment for the parameters. The architecture requires a specification program check if these alignments are not used. Enforcing this alignment also removes a possible host BUG, since the get_guest functions check for proper alignment and emits a BUG. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-27KVM: s390: Fix instruction naming for lctlgChristian Borntraeger
Lets fix the name for the lctlg instruction... Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-27KVM: s390: Fix program check on interrupt delivery handlingChristian Borntraeger
The current interrupt handling on s390 misbehaves on an error case. On s390 each cpu has the prefix area (lowcore) for interrupt delivery. This memory must always be available. If we fail to access the prefix area for a guest on interrupt delivery the configuration is completely unusable. There is no point in sending another program interrupt to an inaccessible lowcore. Furthermore, we should not bug the host kernel, because this can be triggered by userspace. I think the guest kernel itself can not trigger the problem, as SET PREFIX and SIGNAL PROCESSOR SET PREFIX both check that the memory is available and sane. As this is a userspace bug (e.g. setting the wrong guest offset, unmapping guest memory) we should kill the userspace process instead of BUGing the host kernel. In the long term we probably should notify the userspace process about this problem. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-27KVM: s390: Change guestaddr type in gaccessMartin Schwidefsky
All registers are unsigned long types. This patch changes all occurences of guestaddr in gaccess from u64 to unsigned long. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-27KVM: s390: Advertise KVM_CAP_USER_MEMORYCarsten Otte
KVM_CAP_USER_MEMORY is used by s390, therefore, we should advertise it. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: MMU: nuke shadowed pgtable pages and ptes on memslot destructionMarcelo Tosatti
Flush the shadow mmu before removing regions to avoid stale entries. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: s390: rename private structuresChristian Borntraeger
While doing some tests with our lcrash implementation I have seen a naming conflict with prefix_info in kvm_host.h vs. addrconf.h To avoid future conflicts lets rename private definitions in asm/kvm_host.h by adding the kvm_s390 prefix. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: s390: Set guest storage limit and offset to sane valuesChristian Borntraeger
Some machines do not accept 16EB as guest storage limit. Lets change the default for the guest storage limit to a sane value. We also should set the guest_origin to what userspace thinks it is. This allows guests starting at an address != 0. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: Fix memory leak on guest exitCarsten Otte
This patch fixes a memory leak, we want to free the physmem when destroying the vm. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: Remove decache_vcpus_on_cpu() and related callbacksAvi Kivity
Obsoleted by the vmx-specific per-cpu list. Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-06-06KVM: s390: Fix race condition in kvm_s390_handle_waitCarsten Otte
The call to add_timer was issued before local_int.lock was taken and before timer_due was set to 0. If the timer expires before the lock is being taken, the timer function will set timer_due to 1 and exit before the vcpu falls asleep. Depending on other external events, the vcpu might sleep forever. This fix pulls setting timer_due to the beginning of the function before add_timer, which ensures correct behavior. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-06-06KVM: s390: Send program check on access errorCarsten Otte
If the guest accesses non-existing memory, the sie64a function returns -EFAULT. We must check the return value and send a program check to the guest if the sie instruction faulted, otherwise the guest will loop at the faulting code. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-06-06KVM: s390: fix interrupt deliveryCarsten Otte
The current code delivers pending interrupts before it checks for need_resched. On a busy host, this can lead to a longer interrupt latency if the interrupt is injected while the process is scheduled away. This patch moves delivering the interrupt _after_ schedule(), which makes more sense. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>