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2019-01-24KVM: arm/arm64: vgic: Make vgic_irq->irq_lock a raw_spinlockJulien Thierry
vgic_irq->irq_lock must always be taken with interrupts disabled as it is used in interrupt context. For configurations such as PREEMPT_RT_FULL, this means that it should be a raw_spinlock since RT spinlocks are interruptible. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
2018-08-12KVM: arm/arm64: vgic: Do not use spin_lock_irqsave/restore with irq disabledJia He
kvm_vgic_sync_hwstate is only called with IRQ being disabled. There is thus no need to call spin_lock_irqsave/restore in vgic_fold_lr_state and vgic_prune_ap_list. This patch replace them with the non irq-safe version. Signed-off-by: Jia He <jia.he@hxt-semitech.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> [maz: commit message tidy-up] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-21KVM: arm/arm64: vgic: Signal IRQs using their configured groupChristoffer Dall
Now when we have a group configuration on the struct IRQ, use this state when populating the LR and signaling interrupts as either group 0 or group 1 to the VM. Depending on the model of the emulated GIC, and the guest's configuration of the VMCR, interrupts may be signaled as IRQs or FIQs to the VM. Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-27KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGIMarc Zyngier
Now that we make sure we don't inject multiple instances of the same GICv2 SGI at the same time, we've made another bug more obvious: If we exit with an active SGI, we completely lose track of which vcpu it came from. On the next entry, we restore it with 0 as a source, and if that wasn't the right one, too bad. While this doesn't seem to trouble GIC-400, the architectural model gets offended and doesn't deactivate the interrupt on EOI. Another connected issue is that we will happilly make pending an interrupt from another vcpu, overriding the above zero with something that is just as inconsistent. Don't do that. The final issue is that we signal a maintenance interrupt when no pending interrupts are present in the LR. Assuming we've fixed the two issues above, we end-up in a situation where we keep exiting as soon as we've reached the active state, and not be able to inject the following pending. The fix comes in 3 parts: - GICv2 SGIs have their source vcpu saved if they are active on exit, and restored on entry - Multi-SGIs cannot go via the Pending+Active state, as this would corrupt the source field - Multi-SGIs are converted to using MI on EOI instead of NPIE Fixes: 16ca6a607d84bef0 ("KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintid") Reported-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-26KVM: arm/arm64: vgic: Disallow Active+Pending for level interruptsMarc Zyngier
It was recently reported that VFIO mediated devices, and anything that VFIO exposes as level interrupts, do no strictly follow the expected logic of such interrupts as it only lowers the input line when the guest has EOId the interrupt at the GIC level, rather than when it Acked the interrupt at the device level. THe GIC's Active+Pending state is fundamentally incompatible with this behaviour, as it prevents KVM from observing the EOI, and in turn results in VFIO never dropping the line. This results in an interrupt storm in the guest, which it really never expected. As we cannot really change VFIO to follow the strict rules of level signalling, let's forbid the A+P state altogether, as it is in the end only an optimization. It ensures that we will transition via an invalid state, which we can use to notify VFIO of the EOI. Reviewed-by: Eric Auger <eric.auger@redhat.com> Tested-by: Eric Auger <eric.auger@redhat.com> Tested-by: Shunyong Yang <shunyong.yang@hxt-semitech.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19Merge tag 'kvm-arm-fixes-for-v4.16-2' into HEADMarc Zyngier
Resolve conflicts with current mainline
2018-03-19KVM: arm/arm64: Keep GICv2 HYP VAs in kvm_vgic_global_stateMarc Zyngier
As we're about to change the way we map devices at HYP, we need to move away from kern_hyp_va on an IO address. One way of achieving this is to store the VAs in kvm_vgic_global_state, and use that directly from the HYP code. This requires a small change to create_hyp_io_mappings so that it can also return a HYP VA. We take this opportunity to nuke the vctrl_base field in the emulated distributor, as it is not used anymore. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move ioremap calls to create_hyp_io_mappingsMarc Zyngier
Both HYP io mappings call ioremap, followed by create_hyp_io_mappings. Let's move the ioremap call into create_hyp_io_mappings itself, which simplifies the code a bit and allows for further refactoring. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move VGIC APR save/restore to vgic put/loadChristoffer Dall
The APRs can only have bits set when the guest acknowledges an interrupt in the LR and can only have a bit cleared when the guest EOIs an interrupt in the LR. Therefore, if we have no LRs with any pending/active interrupts, the APR cannot change value and there is no need to clear it on every exit from the VM (hint: it will have already been cleared when we exited the guest the last time with the LRs all EOIed). The only case we need to take care of is when we migrate the VCPU away from a CPU or migrate a new VCPU onto a CPU, or when we return to userspace to capture the state of the VCPU for migration. To make sure this works, factor out the APR save/restore functionality into separate functions called from the VCPU (and by extension VGIC) put/load hooks. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Handle VGICv2 save/restore from the main VGIC codeChristoffer Dall
We can program the GICv2 hypervisor control interface logic directly from the core vgic code and can instead do the save/restore directly from the flush/sync functions, which can lead to a number of future optimizations. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Get rid of vgic_elrsrChristoffer Dall
There is really no need to store the vgic_elrsr on the VGIC data structures as the only need we have for the elrsr is to figure out if an LR is inactive when we save the VGIC state upon returning from the guest. We can might as well store this in a temporary local variable. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintidMarc Zyngier
The vgic code is trying to be clever when injecting GICv2 SGIs, and will happily populate LRs with the same interrupt number if they come from multiple vcpus (after all, they are distinct interrupt sources). Unfortunately, this is against the letter of the architecture, and the GICv2 architecture spec says "Each valid interrupt stored in the List registers must have a unique VirtualID for that virtual CPU interface.". GICv3 has similar (although slightly ambiguous) restrictions. This results in guests locking up when using GICv2-on-GICv3, for example. The obvious fix is to stop trying so hard, and inject a single vcpu per SGI per guest entry. After all, pending SGIs with multiple source vcpus are pretty rare, and are mostly seen in scenario where the physical CPUs are severely overcomitted. But as we now only inject a single instance of a multi-source SGI per vcpu entry, we may delay those interrupts for longer than strictly necessary, and run the risk of injecting lower priority interrupts in the meantime. In order to address this, we adopt a three stage strategy: - If we encounter a multi-source SGI in the AP list while computing its depth, we force the list to be sorted - When populating the LRs, we prevent the injection of any interrupt of lower priority than that of the first multi-source SGI we've injected. - Finally, the injection of a multi-source SGI triggers the request of a maintenance interrupt when there will be no pending interrupt in the LRs (HCR_NPIE). At the point where the last pending interrupt in the LRs switches from Pending to Active, the maintenance interrupt will be delivered, allowing us to add the remaining SGIs using the same process. Cc: stable@vger.kernel.org Fixes: 0919e84c0fc1 ("KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework") Acked-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: Reduce verbosity of KVM init logArd Biesheuvel
On my GICv3 system, the following is printed to the kernel log at boot: kvm [1]: 8-bit VMID kvm [1]: IDMAP page: d20e35000 kvm [1]: HYP VA range: 800000000000:ffffffffffff kvm [1]: vgic-v2@2c020000 kvm [1]: GIC system register CPU interface enabled kvm [1]: vgic interrupt IRQ1 kvm [1]: virtual timer IRQ4 kvm [1]: Hyp mode initialized successfully The KVM IDMAP is a mapping of a statically allocated kernel structure, and so printing its physical address leaks the physical placement of the kernel when physical KASLR in effect. So change the kvm_info() to kvm_debug() to remove it from the log output. While at it, trim the output a bit more: IRQ numbers can be found in /proc/interrupts, and the HYP VA and vgic-v2 lines are not highly informational either. Cc: <stable@vger.kernel.org> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-01-02KVM: arm/arm64: vgic: Support level-triggered mapped interruptsChristoffer Dall
Level-triggered mapped IRQs are special because we only observe rising edges as input to the VGIC, and we don't set the EOI flag and therefore are not told when the level goes down, so that we can re-queue a new interrupt when the level goes up. One way to solve this problem is to side-step the logic of the VGIC and special case the validation in the injection path, but it has the unfortunate drawback of having to peak into the physical GIC state whenever we want to know if the interrupt is pending on the virtual distributor. Instead, we can maintain the current semantics of a level triggered interrupt by sort of treating it as an edge-triggered interrupt, following from the fact that we only observe an asserting edge. This requires us to be a bit careful when populating the LRs and when folding the state back in though: * We lower the line level when populating the LR, so that when subsequently observing an asserting edge, the VGIC will do the right thing. * If the guest never acked the interrupt while running (for example if it had masked interrupts at the CPU level while running), we have to preserve the pending state of the LR and move it back to the line_level field of the struct irq when folding LR state. If the guest never acked the interrupt while running, but changed the device state and lowered the line (again with interrupts masked) then we need to observe this change in the line_level. Both of the above situations are solved by sampling the physical line and set the line level when folding the LR back. * Finally, if the guest never acked the interrupt while running and sampling the line reveals that the device state has changed and the line has been lowered, we must clear the physical active state, since we will otherwise never be told when the interrupt becomes asserted again. This has the added benefit of making the timer optimization patches (https://lists.cs.columbia.edu/pipermail/kvmarm/2017-July/026343.html) a bit simpler, because the timer code doesn't have to clear the active state on the sync anymore. It also potentially improves the performance of the timer implementation because the GIC knows the state or the LR and only needs to clear the active state when the pending bit in the LR is still set, where the timer has to always clear it when returning from running the guest with an injected timer interrupt. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-06KVM: arm/arm64: Support calling vgic_update_irq_pending from irq contextChristoffer Dall
We are about to optimize our timer handling logic which involves injecting irqs to the vgic directly from the irq handler. Unfortunately, the injection path can take any AP list lock and irq lock and we must therefore make sure to use spin_lock_irqsave where ever interrupts are enabled and we are taking any of those locks, to avoid deadlocking between process context and the ISR. This changes a lot of the VGIC code, but the good news are that the changes are mostly mechanical. Acked-by: Marc Zyngier <marc,zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-24KVM: arm/arm64: Fix isues with GICv2 on GICv3 migrationChristoffer Dall
We have been a little loose with our intermediate VMCR representation where we had a 'ctlr' field, but we failed to differentiate between the GICv2 GICC_CTLR and ICC_CTLR_EL1 layouts, and therefore ended up mapping the wrong bits into the individual fields of the ICH_VMCR_EL2 when emulating a GICv2 on a GICv3 system. Fix this by using explicit fields for the VMCR bits instead. Cc: Eric Auger <eric.auger@redhat.com> Reported-by: wanghaibin <wanghaibin.wang@huawei.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-15KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interruptMarc Zyngier
When an interrupt is injected with the HW bit set (indicating that deactivation should be propagated to the physical distributor), special care must be taken so that we never mark the corresponding LR with the Active+Pending state (as the pending state is kept in the physycal distributor). Cc: stable@vger.kernel.org Fixes: 140b086dd197 ("KVM: arm/arm64: vgic-new: Add GICv2 world switch backend") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-08Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - HYP mode stub supports kexec/kdump on 32-bit - improved PMU support - virtual interrupt controller performance improvements - support for userspace virtual interrupt controller (slower, but necessary for KVM on the weird Broadcom SoCs used by the Raspberry Pi 3) MIPS: - basic support for hardware virtualization (ImgTec P5600/P6600/I6400 and Cavium Octeon III) PPC: - in-kernel acceleration for VFIO s390: - support for guests without storage keys - adapter interruption suppression x86: - usual range of nVMX improvements, notably nested EPT support for accessed and dirty bits - emulation of CPL3 CPUID faulting generic: - first part of VCPU thread request API - kvm_stat improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits) kvm: nVMX: Don't validate disabled secondary controls KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick Revert "KVM: Support vCPU-based gfn->hva cache" tools/kvm: fix top level makefile KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING KVM: Documentation: remove VM mmap documentation kvm: nVMX: Remove superfluous VMX instruction fault checks KVM: x86: fix emulation of RSM and IRET instructions KVM: mark requests that need synchronization KVM: return if kvm_vcpu_wake_up() did wake up the VCPU KVM: add explicit barrier to kvm_vcpu_kick KVM: perform a wake_up in kvm_make_all_cpus_request KVM: mark requests that do not need a wakeup KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up KVM: x86: always use kvm_make_request instead of set_bit KVM: add kvm_{test,clear}_request to replace {test,clear}_bit s390: kvm: Cpu model support for msa6, msa7 and msa8 KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK kvm: better MWAIT emulation for guests KVM: x86: virtualize cpuid faulting ...
2017-04-09KVM: arm/arm64: vgic: Improve sync_hwstate performanceChristoffer Dall
There is no need to call any functions to fold LRs when we don't use any LRs and we don't need to mess with overflow flags, take spinlocks, or prune the AP list if the AP list is empty. Note: list_empty is a single atomic read (uses READ_ONCE) and can therefore check if a list is empty or not without the need to take the spinlock protecting the list. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-09KVM: arm/arm64: vgic: Get rid of unnecessary process_maintenance operationChristoffer Dall
Since we always read back the LRs that we wrote to the guest and the MISR and EISR registers simply provide a summary of the configuration of the bits in the LRs, there is really no need to read back those status registers and process them. We might as well just signal the notifyfd when folding the LR state and save some cycles in the process. We now clear the underflow bit in the fold_lr_state functions as we only need to clear this bit if we had used all the LRs, so this is as good a place as any to do that work. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-04-09KVM: arm/arm64: vgic: Defer touching GICH_VMCR to vcpu_load/putChristoffer Dall
We don't have to save/restore the VMCR on every entry to/from the guest, since on GICv2 we can access the control interface from EL1 and on VHE systems with GICv3 we can access the control interface from KVM running in EL2. GICv3 systems without VHE becomes the rare case, which has to save/restore the register on each round trip. Note that userspace accesses may see out-of-date values if the VCPU is running while accessing the VGIC state via the KVM device API, but this is already the case and it is up to userspace to quiesce the CPUs before reading the CPU registers from the GIC for an up-to-date view. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-04KVM: arm/arm64: vgic: Fix GICC_PMR uaccess on GICv3 and clarify ABIChristoffer Dall
As an oversight, for GICv2, we accidentally export the GICC_PMR register in the format of the GICH_VMCR.VMPriMask field in the lower 5 bits of a word, meaning that userspace must always use the lower 5 bits to communicate with the KVM device and must shift the value left by 3 places to obtain the actual priority mask level. Since GICv3 supports the full 8 bits of priority masking in the ICH_VMCR, we have to fix the value we export when emulating a GICv2 on top of a hardware GICv3 and exporting the emulated GICv2 state to userspace. Take the chance to clarify this aspect of the ABI. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-04KVM: arm64: Ensure LRs are clear when they should beChristoffer Dall
We currently have some code to clear the list registers on GICv3, but we never call this code, because the caller got nuked when removing the old vgic. We also used to have a similar GICv2 part, but that got lost in the process too. Let's reintroduce the logic for GICv2 and call the logic when we initialize the use of hypervisors on the CPU, for example when first loading KVM or when exiting a low power state. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-25KVM: arm/arm64: Remove struct vgic_irq pending fieldChristoffer Dall
One of the goals behind the VGIC redesign was to get rid of cached or intermediate state in the data structures, but we decided to allow ourselves to precompute the pending value of an IRQ based on the line level and pending latch state. However, this has now become difficult to base proper GICv3 save/restore on, because there is a potential to modify the pending state without knowing if an interrupt is edge or level configured. See the following post and related message for more background: https://lists.cs.columbia.edu/pipermail/kvmarm/2017-January/023195.html This commit gets rid of the precomputed pending field in favor of a function that calculates the value when needed, irq_is_pending(). The soft_pending field is renamed to pending_latch to represent that this latch is the equivalent hardware latch which gets manipulated by the input signal for edge-triggered interrupts and when writing to the SPENDR/CPENDR registers. After this commit save/restore code should be able to simply restore the pending_latch state, line_level state, and config state in any order and get the desired result. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-01-13KVM: arm/arm64: vgic: Fix deadlock on error handlingMarc Zyngier
Dmitry Vyukov reported that the syzkaller fuzzer triggered a deadlock in the vgic setup code when an error was detected, as the cleanup code tries to take a lock that is already held by the setup code. The fix is to avoid retaking the lock when cleaning up, by telling the cleanup function that we already hold it. Cc: stable@vger.kernel.org Reported-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-24KVM: arm/arm64: vgic: Don't notify EOI for non-SPIsMarc Zyngier
When we inject a level triggerered interrupt (and unless it is backed by the physical distributor - timer style), we request a maintenance interrupt. Part of the processing for that interrupt is to feed to the rest of KVM (and to the eventfd subsystem) the information that the interrupt has been EOIed. But that notification only makes sense for SPIs, and not PPIs (such as the PMU interrupt). Skip over the notification if the interrupt is not an SPI. Cc: stable@vger.kernel.org # 4.7+ Fixes: 140b086dd197 ("KVM: arm/arm64: vgic-new: Add GICv2 world switch backend") Fixes: 59529f69f504 ("KVM: arm/arm64: vgic-new: Add GICv3 world switch backend") Reported-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-09-08arm64: KVM: vgic-v2: Enable GICV access from HYP if access from guest is unsafeMarc Zyngier
So far, we've been disabling KVM on systems where the GICV region couldn't be safely given to a guest. Now that we're able to handle this access safely by emulating it in HYP, we can enable this feature when we detect an unsafe configuration. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08arm64: KVM: vgic-v2: Add the GICV emulation infrastructureMarc Zyngier
In order to efficiently perform the GICV access on behalf of the guest, we need to be able to avoid going back all the way to the host kernel. For this, we introduce a new hook in the world switch code, conveniently placed just after populating the fault info. At that point, we only have saved/restored the GP registers, and we can quickly perform all the required checks (data abort, translation fault, valid faulting syndrome, not an external abort, not a PTW). Coming back from the emulation code, we need to skip the emulated instruction. This involves an additional bit of save/restore in order to be able to access the guest's PC (and possibly CPSR if this is a 32bit guest). At this stage, no emulation code is provided. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-18KVM: arm/arm64: vgic: Add refcounting for IRQsAndre Przywara
In the moment our struct vgic_irq's are statically allocated at guest creation time. So getting a pointer to an IRQ structure is trivial and safe. LPIs are more dynamic, they can be mapped and unmapped at any time during the guest's _runtime_. In preparation for supporting LPIs we introduce reference counting for those structures using the kernel's kref infrastructure. Since private IRQs and SPIs are statically allocated, we avoid actually refcounting them, since they would never be released anyway. But we take provisions to increase the refcount when an IRQ gets onto a VCPU list and decrease it when it gets removed. Also this introduces vgic_put_irq(), which wraps kref_put and hides the release function from the callers. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm/arm64: vgic: Check return value for kvm_register_vgic_deviceAndre Przywara
kvm_register_device_ops() can return an error, so lets check its return value and propagate this up the call chain. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-31KVM: arm/arm64: vgic-v2: Always resample level interruptsMarc Zyngier
When reading back from the list registers, we need to perform two actions for level interrupts: 1) clear the soft-pending bit if the interrupt is not pending anymore *in the list register* 2) resample the line level and propagate it to the pending state But these two actions shouldn't be linked, and we should *always* resample the line level, no matter what state is in the list register. Otherwise, we may end-up injecting spurious interrupts that have been already retired. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20KVM: arm/arm64: vgic-new: Add vgic_v2/v3_enableEric Auger
Enable the VGIC operation by properly initialising the registers in the hypervisor GIC interface. Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20KVM: arm/arm64: vgic-new: vgic_init: implement map_resourcesEric Auger
map_resources is the last initialization step. It is executed on first VCPU run. At that stage the code checks that userspace has provided the base addresses for the relevant VGIC regions, which depend on the type of VGIC that is exposed to the guest. Also we check if the two regions overlap. If the checks succeeded, we register the respective register frames with the kvm_io_bus framework. If we emulate a GICv2, the function also forces vgic_init execution if it has not been executed yet. Also we map the virtual GIC CPU interface onto the guest's CPU interface. Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20KVM: arm/arm64: vgic-new: vgic_init: implement vgic_initEric Auger
This patch allocates and initializes the data structures used to model the vgic distributor and virtual cpu interfaces. At that stage the number of IRQs and number of virtual CPUs is frozen. Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_initEric Auger
Implements kvm_vgic_hyp_init and vgic_probe function. This uses the new firmware independent VGIC probing to support both ACPI and DT based systems (code from Marc Zyngier). The vgic_global struct is enriched with new fields populated by those functions. Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20KVM: arm/arm64: vgic-new: Add GICH_VMCR accessorsAndre Przywara
Since the GIC CPU interface is always virtualized by the hardware, we don't have CPU interface state information readily available in our emulation if userland wants to save or restore it. Fortunately the GIC hypervisor interface provides the VMCR register to access the required virtual CPU interface bits. Provide wrappers for GICv2 and GICv3 hosts to have access to this register. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20KVM: arm/arm64: vgic-new: Add GICv2 world switch backendMarc Zyngier
Processing maintenance interrupts and accessing the list registers are dependent on the host's GIC version. Introduce vgic-v2.c to contain GICv2 specific functions. Implement the GICv2 specific code for syncing the emulation state into the VGIC registers. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>