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* kvm: Check irqchip mode before assign irqfdPeter Xu2019-05-241-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | When assigning kvm irqfd we didn't check the irqchip mode but we allow KVM_IRQFD to succeed with all the irqchip modes. However it does not make much sense to create irqfd even without the kernel chips. Let's provide a arch-dependent helper to check whether a specific irqfd is allowed by the arch. At least for x86, it should make sense to check: - when irqchip mode is NONE, all irqfds should be disallowed, and, - when irqchip mode is SPLIT, irqfds that are with resamplefd should be disallowed. For either of the case, previously we'll silently ignore the irq or the irq ack event if the irqchip mode is incorrect. However that can cause misterious guest behaviors and it can be hard to triage. Let's fail KVM_IRQFD even earlier to detect these incorrect configurations. CC: Paolo Bonzini <pbonzini@redhat.com> CC: Radim Krčmář <rkrcmar@redhat.com> CC: Alex Williamson <alex.williamson@redhat.com> CC: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Rename interrupt.pending to interrupt.injectedLiran Alon2018-03-281-2/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For exceptions & NMIs events, KVM code use the following coding convention: *) "pending" represents an event that should be injected to guest at some point but it's side-effects have not yet occurred. *) "injected" represents an event that it's side-effects have already occurred. However, interrupts don't conform to this coding convention. All current code flows mark interrupt.pending when it's side-effects have already taken place (For example, bit moved from LAPIC IRR to ISR). Therefore, it makes sense to just rename interrupt.pending to interrupt.injected. This change follows logic of previous commit 664f8e26b00c ("KVM: X86: Fix loss of exception which has not yet been injected") which changed exception to follow this coding convention as well. It is important to note that in case !lapic_in_kernel(vcpu), interrupt.pending usage was and still incorrect. In this case, interrrupt.pending can only be set using one of the following ioctls: KVM_INTERRUPT, KVM_SET_VCPU_EVENTS and KVM_SET_SREGS. Looking at how QEMU uses these ioctls, one can see that QEMU uses them either to re-set an "interrupt.pending" state it has received from KVM (via KVM_GET_VCPU_EVENTS interrupt.pending or via KVM_GET_SREGS interrupt_bitmap) or by dispatching a new interrupt from QEMU's emulated LAPIC which reset bit in IRR and set bit in ISR before sending ioctl to KVM. So it seems that indeed "interrupt.pending" in this case is also suppose to represent "interrupt.injected". However, kvm_cpu_has_interrupt() & kvm_cpu_has_injectable_intr() is misusing (now named) interrupt.injected in order to return if there is a pending interrupt. This leads to nVMX/nSVM not be able to distinguish if it should exit from L2 to L1 on EXTERNAL_INTERRUPT on pending interrupt or should re-inject an injected interrupt. Therefore, add a FIXME at these functions for handling this issue. This patch introduce no semantics change. Signed-off-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* KVM: nVMX: Fix injection to L2 when L1 don't intercept external-interruptsLiran Alon2018-01-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before each vmentry to guest, vcpu_enter_guest() calls sync_pir_to_irr() which calls vmx_hwapic_irr_update() to update RVI. Currently, vmx_hwapic_irr_update() contains a tweak in case it is called when CPU is running L2 and L1 don't intercept external-interrupts. In that case, code injects interrupt directly into L2 instead of updating RVI. Besides being hacky (wouldn't expect function updating RVI to also inject interrupt), it also doesn't handle this case correctly. The code contains several issues: 1. When code calls kvm_queue_interrupt() it just passes it max_irr which represents the highest IRR currently pending in L1 LAPIC. This is problematic as interrupt was injected to guest but it's bit is still set in LAPIC IRR instead of being cleared from IRR and set in ISR. 2. Code doesn't check if LAPIC PPR is set to accept an interrupt of max_irr priority. It just checks if interrupts are enabled in guest with vmx_interrupt_allowed(). To fix the above issues: 1. Simplify vmx_hwapic_irr_update() to just update RVI. Note that this shouldn't happen when CPU is running L2 (See comment in code). 2. Since now vmx_hwapic_irr_update() only does logic for L1 virtual-interrupt-delivery, inject_pending_event() should be the one responsible for injecting the interrupt directly into L2. Therefore, change kvm_cpu_has_injectable_intr() to check L1 LAPIC when CPU is running L2. 3. Change vmx_sync_pir_to_irr() to set KVM_REQ_EVENT when L1 has a pending injectable interrupt. Fixes: 963fee165660 ("KVM: nVMX: Fix virtual interrupt delivery injection") Signed-off-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com> Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Signed-off-by: Liam Merwick <liam.merwick@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* KVM: x86: get rid of pic_irqchip()David Hildenbrand2017-04-121-1/+1
| | | | | | | | | | 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>
* x86/kvm: Audit and remove any unnecessary uses of module.hPaul Gortmaker2016-07-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. In the case of kvm where it is modular, we can extend that to also include files that are building basic support functionality but not related to loading or registering the final module; such files also have no need whatsoever for module.h The advantage in removing such instances is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each instance for the presence of either and replace as needed. Several instances got replaced with moduleparam.h since that was really all that was required for those particular files. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/20160714001901.31603-8-paul.gortmaker@windriver.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* KVM: x86: consolidate "has lapic" checks into irq.cPaolo Bonzini2016-02-091-3/+6
| | | | | | | | Do for kvm_cpu_has_pending_timer and kvm_inject_pending_timer_irqs what the other irq.c routines have been doing. Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm/x86: per-vcpu apicv deactivation supportAndrey Smetanin2015-11-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | The decision on whether to use hardware APIC virtualization used to be taken globally, based on the availability of the feature in the CPU and the value of a module parameter. However, under certain circumstances we want to control it on per-vcpu basis. In particular, when the userspace activates HyperV synthetic interrupt controller (SynIC), APICv has to be disabled as it's incompatible with SynIC auto-EOI behavior. To achieve that, introduce 'apicv_active' flag on struct kvm_vcpu_arch, and kvm_vcpu_deactivate_apicv() function to turn APICv off. The flag is initialized based on the module parameter and CPU capability, and consulted whenever an APICv-specific action is performed. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Add support for local interrupt requests from userspaceSteve Rutherford2015-10-011-6/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to enable userspace PIC support, the userspace PIC needs to be able to inject local interrupts even when the APICs are in the kernel. KVM_INTERRUPT now supports sending local interrupts to an APIC when APICs are in the kernel. The ready_for_interrupt_request flag is now only set when the CPU/APIC will immediately accept and inject an interrupt (i.e. APIC has not masked the PIC). When the PIC wishes to initiate an INTA cycle with, say, CPU0, it kicks CPU0 out of the guest, and renedezvous with CPU0 once it arrives in userspace. When the CPU/APIC unmasks the PIC, a KVM_EXIT_IRQ_WINDOW_OPEN is triggered, so that userspace has a chance to inject a PIC interrupt if it had been pending. Overall, this design can lead to a small number of spurious userspace renedezvous. In particular, whenever the PIC transistions from low to high while it is masked and whenever the PIC becomes unmasked while it is low. Note: this does not buffer more than one local interrupt in the kernel, so the VMM needs to enter the guest in order to complete interrupt injection before injecting an additional interrupt. Compiles for x86. Can pass the KVM Unit Tests. Signed-off-by: Steve Rutherford <srutherford@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: introduce lapic_in_kernelPaolo Bonzini2015-10-011-3/+3
| | | | | | | | Avoid pointer chasing and memory barriers, and simplify the code when split irqchip (LAPIC in kernel, IOAPIC/PIC in userspace) is introduced. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: replace vm_has_apicv hook with cpu_uses_apicvPaolo Bonzini2015-10-011-1/+1
| | | | | | This will avoid an unnecessary trip to ->kvm and from there to the VPIC. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: fix "acknowledge interrupt on exit" when APICv is in useWanpeng Li2014-08-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 77b0f5d (KVM: nVMX: Ack and write vector info to intr_info if L1 asks us to), "Acknowledge interrupt on exit" behavior can be emulated. To do so, KVM will ask the APIC for the interrupt vector if during a nested vmexit if VM_EXIT_ACK_INTR_ON_EXIT is set. With APICv, kvm_get_apic_interrupt would return -1 and give the following WARNING: Call Trace: [<ffffffff81493563>] dump_stack+0x49/0x5e [<ffffffff8103f0eb>] warn_slowpath_common+0x7c/0x96 [<ffffffffa059709a>] ? nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffff8103f11a>] warn_slowpath_null+0x15/0x17 [<ffffffffa059709a>] nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffffa0594295>] ? nested_vmx_exit_handled+0x6a/0x39e [kvm_intel] [<ffffffffa0537931>] ? kvm_apic_has_interrupt+0x80/0xd5 [kvm] [<ffffffffa05972ec>] vmx_check_nested_events+0xc3/0xd3 [kvm_intel] [<ffffffffa051ebe9>] inject_pending_event+0xd0/0x16e [kvm] [<ffffffffa051efa0>] vcpu_enter_guest+0x319/0x704 [kvm] To fix this, we cannot rely on the processor's virtual interrupt delivery, because "acknowledge interrupt on exit" must only update the virtual ISR/PPR/IRR registers (and SVI, which is just a cache of the virtual ISR) but it should not deliver the interrupt through the IDT. Thus, KVM has to deliver the interrupt "by hand", similar to the treatment of EOI in commit fc57ac2c9ca8 (KVM: lapic: sync highest ISR to hardware apic on EOI, 2014-05-14). The patch modifies kvm_cpu_get_interrupt to always acknowledge an interrupt; there are only two callers, and the other is not affected because it is never reached with kvm_apic_vid_enabled() == true. Then it modifies apic_set_isr and apic_clear_irr to update SVI and RVI in addition to the registers. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Suggested-by: "Zhang, Yang Z" <yang.z.zhang@intel.com> Tested-by: Liu, RongrongX <rongrongx.liu@intel.com> Tested-by: Felipe Reyes <freyes@suse.com> Fixes: 77b0f5d67ff2781f36831cba79674c3e97bd7acf Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Ack and write vector info to intr_info if L1 asks us toBandan Das2014-04-221-0/+1
| | | | | | | | | This feature emulates the "Acknowledge interrupt on exit" behavior. We can safely emulate it for L1 to run L2 even if L0 itself has it disabled (to run L1). Signed-off-by: Bandan Das <bsd@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* x86, apicv: add virtual interrupt delivery supportYang Zhang2013-01-291-5/+51
| | | | | | | | | | | | | | | | | | | Virtual interrupt delivery avoids KVM to inject vAPIC interrupts manually, which is fully taken care of by the hardware. This needs some special awareness into existing interrupr injection path: - for pending interrupt, instead of direct injection, we may need update architecture specific indicators before resuming to guest. - A pending interrupt, which is masked by ISR, should be also considered in above update action, since hardware will decide when to inject it at right time. Current has_interrupt and get_interrupt only returns a valid vector from injection p.o.v. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: remove unused variable.Gleb Natapov2012-12-141-4/+0
| | | | | Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: inject ExtINT interrupt before APIC interruptsGleb Natapov2012-12-131-18/+8
| | | | | | | | | | | | | 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>
* KVM: fix typo in copyright noticeNicolas Kaiser2010-10-241-1/+1
| | | | | | | Fix typo in copyright notice. Signed-off-by: Nicolas Kaiser <nikai@nikai.net> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: pit: Do not check pending pit timer in vcpu threadJason Wang2010-10-241-6/+1
| | | | | | | | | Pit interrupt injection was done by workqueue, so no need to check pending pit timer in vcpu thread which could lead unnecessary unblocking of vcpu. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: x86: Introduce a workqueue to deliver PIT timer interruptsChris Lalancette2010-08-011-1/+0
| | | | | | | | | | We really want to "kvm_set_irq" during the hrtimer callback, but that is risky because that is during interrupt context. Instead, offload the work to a workqueue, which is a bit safer and should provide most of the same functionality. Signed-off-by: Chris Lalancette <clalance@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: Update Red Hat copyrightsAvi Kivity2010-08-011-0/+1
| | | | Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Remove irq_pending bitmapGleb Natapov2009-06-101-2/+2
| | | | | | | | | Only one interrupt vector can be injected from userspace irqchip at any given time so no need to store it in a bitmap. Put it into interrupt queue directly. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Make kvm_cpu_(has|get)_interrupt() work for userspace irqchip tooGleb Natapov2009-06-101-0/+7
| | | | | | | At the vector level, kernel and userspace irqchip are fairly similar. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: x86: fix LAPIC pending count calculationMarcelo Tosatti2009-02-151-7/+0
| | | | | | | | | | | Simplify LAPIC TMCCT calculation by using hrtimer provided function to query remaining time until expiration. Fixes host hang with nested ESX. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: Separate irq ack notification out of arch/x86/kvm/irq.cXiantao Zhang2008-10-151-33/+0
| | | | | | | | Moving irq ack notification logic as common, and make it shared with ia64 side. Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: PIT: fix injection logic and countMarcelo Tosatti2008-10-151-1/+0
| | | | | | | | | | | | | | | | | | | | The PIT injection logic is problematic under the following cases: 1) If there is a higher priority vector to be delivered by the time kvm_pit_timer_intr_post is invoked ps->inject_pending won't be set. This opens the possibility for missing many PIT event injections (say if guest executes hlt at this point). 2) ps->inject_pending is racy with more than two vcpus. Since there's no locking around read/dec of pt->pending, two vcpu's can inject two interrupts for a single pt->pending count. Fix 1 by using an irq ack notifier: only reinject when the previous irq has been acked. Fix 2 with appropriate locking around manipulation of pending count and irq_ack by the injection / ack paths. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: irq ack notificationMarcelo Tosatti2008-10-151-1/+1
| | | | | | | | | | | | | | | | Based on a patch from: Ben-Ami Yassour <benami@il.ibm.com> which was based on a patch from: Amit Shah <amit.shah@qumranet.com> Notify IRQ acking on PIC/APIC emulation. The previous patch missed two things: - Edge triggered interrupts on IOAPIC - PIC reset with IRR/ISR set should be equivalent to ack (LAPIC probably needs something similar). Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> CC: Amit Shah <amit.shah@qumranet.com> CC: Ben-Ami Yassour <benami@il.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: Add irq ack notifier listAvi Kivity2008-10-151-0/+22
| | | | | | | This can be used by kvm subsystems that are interested in when interrupts are acked, for example time drift compensation. Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: Introduce kvm_set_irq to inject interrupts in guestsAmit Shah2008-10-151-0/+11
| | | | | | | | This function injects an interrupt into the guest given the kvm struct, the (guest) irq number and the interrupt level. Signed-off-by: Amit Shah <amit.shah@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: migrate PIT timerMarcelo Tosatti2008-06-061-0/+6
| | | | | | | | | Migrate the PIT timer to the physical CPU which vcpu0 is scheduled on, similarly to what is done for the LAPIC timers, otherwise PIT interrupts will be delayed until an unrelated event causes an exit. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: hlt emulation should take in-kernel APIC/PIT timers into accountMarcelo Tosatti2008-04-271-0/+15
| | | | | | | | | | | | | | | | | | Timers that fire between guest hlt and vcpu_block's add_wait_queue() are ignored, possibly resulting in hangs. Also make sure that atomic_inc and waitqueue_active tests happen in the specified order, otherwise the following race is open: CPU0 CPU1 if (waitqueue_active(wq)) add_wait_queue() if (!atomic_read(pit_timer->pending)) schedule() atomic_inc(pit_timer->pending) Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: In kernel PIT modelSheng Yang2008-04-271-0/+3
| | | | | | | | | | | | The patch moves the PIT model from userspace to kernel, and increases the timer accuracy greatly. [marcelo: make last_injected_time per-guest] Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: Move kvm_vcpu_kick() to x86.cZhang Xiantao2008-01-301-20/+0
| | | | | | | | Moving kvm_vcpu_kick() to x86.c. Since it should be common for all archs, put its declarations in <linux/kvm_host.h> Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* KVM: Move arch dependent files to new directory arch/x86/kvm/Avi Kivity2008-01-301-0/+98
This paves the way for multiple architecture support. Note that while ioapic.c could potentially be shared with ia64, it is also moved. Signed-off-by: Avi Kivity <avi@qumranet.com>
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