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2017-06-14KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interruptMarc Zyngier
commit ddf42d068f8802de122bb7efdfcb3179336053f1 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14KVM: arm/arm64: vgic-v3: Do not use Active+Pending state for a HW interruptMarc Zyngier
commit 3d6e77ad1489650afa20da92bb589c8778baa8da upstream. 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). Fixes: 59529f69f504 ("KVM: arm/arm64: vgic-new: Add GICv3 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-18KVM: arm/arm64: Let vcpu thread modify its own active stateJintack Lim
commit 370a0ec1819990f8e2a93df7cc9c0146980ed45f upstream. Currently, if a vcpu thread tries to change the active state of an interrupt which is already on the same vcpu's AP list, it will loop forever. Since the VGIC mmio handler is called after a vcpu has already synced back the LR state to the struct vgic_irq, we can just let it proceed safely. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Signed-off-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-12KVM: arm/arm64: vgic: Stop injecting the MSI occurrence twiceShanker Donthineni
commit 0bdbf3b071986ba80731203683cf623d5c0cacb1 upstream. The IRQFD framework calls the architecture dependent function twice if the corresponding GSI type is edge triggered. For ARM, the function kvm_set_msi() is getting called twice whenever the IRQFD receives the event signal. The rest of the code path is trying to inject the MSI without any validation checks. No need to call the function vgic_its_inject_msi() second time to avoid an unnecessary overhead in IRQ queue logic. It also avoids the possibility of VM seeing the MSI twice. Simple fix, return -1 if the argument 'level' value is zero. Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-26KVM: arm/arm64: vgic: Fix deadlock on error handlingMarc Zyngier
commit 1193e6aeecb36c74c48c7cd0f641acbbed9ddeef upstream. 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. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
2016-11-18KVM: arm64: Fix the issues when guest PMCCFILTR is configuredWei Huang
KVM calls kvm_pmu_set_counter_event_type() when PMCCFILTR is configured. But this function can't deals with PMCCFILTR correctly because the evtCount bits of PMCCFILTR, which is reserved 0, conflits with the SW_INCR event type of other PMXEVTYPER<n> registers. To fix it, when eventsel == 0, this function shouldn't return immediately; instead it needs to check further if select_idx is ARMV8_PMU_CYCLE_IDX. Another issue is that KVM shouldn't copy the eventsel bits of PMCCFILTER blindly to attr.config. Instead it ought to convert the request to the "cpu cycle" event type (i.e. 0x11). To support this patch and to prevent duplicated definitions, a limited set of ARMv8 perf event types were relocated from perf_event.c to asm/perf_event.h. Cc: stable@vger.kernel.org # 4.6+ Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Wei Huang <wei@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-04KVM: arm/arm64: vgic: Kick VCPUs when queueing already pending IRQsShih-Wei Li
In cases like IPI, we could be queueing an interrupt for a VCPU that is already running and is not about to exit, because the VCPU has entered the VM with the interrupt pending and would not trap on EOI'ing that interrupt. This could result to delays in interrupt deliveries or even loss of interrupts. To guarantee prompt interrupt injection, here we have to try to kick the VCPU. Signed-off-by: Shih-Wei Li <shihwei@cs.columbia.edu> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-04KVM: arm/arm64: vgic: Prevent access to invalid SPIsAndre Przywara
In our VGIC implementation we limit the number of SPIs to a number that the userland application told us. Accordingly we limit the allocation of memory for virtual IRQs to that number. However in our MMIO dispatcher we didn't check if we ever access an IRQ beyond that limit, leading to out-of-bound accesses. Add a test against the number of allocated SPIs in check_region(). Adjust the VGIC_ADDR_TO_INT macro to avoid an actual division, which is not implemented on ARM(32). [maz: cleaned-up original patch] Cc: stable@vger.kernel.org Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-09-27KVM: arm/arm64: vgic: Don't flush/sync without a working vgicChristoffer Dall
If the vgic hasn't been created and initialized, we shouldn't attempt to look at its data structures or flush/sync anything to the GIC hardware. This fixes an issue reported by Alexander Graf when using a userspace irqchip. Fixes: 0919e84c0fc1 ("KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework") Cc: stable@vger.kernel.org Reported-by: Alexander Graf <agraf@suse.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-27KVM: arm64: Require in-kernel irqchip for PMU supportChristoffer Dall
If userspace creates a PMU for the VCPU, but doesn't create an in-kernel irqchip, then we end up in a nasty path where we try to take an uninitialized spinlock, which can lead to all sorts of breakages. Luckily, QEMU always creates the VGIC before the PMU, so we can establish this as ABI and check for the VGIC in the PMU init stage. This can be relaxed at a later time if we want to support PMU with a userspace irqchip. Cc: stable@vger.kernel.org Cc: Shannon Zhao <shannon.zhao@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22ARM: KVM: Support vgic-v3Vladimir Murzin
This patch allows to build and use vgic-v3 in 32-bit mode. Unfortunately, it can not be split in several steps without extra stubs to keep patches independent and bisectable. For instance, virt/kvm/arm/vgic/vgic-v3.c uses function from vgic-v3-sr.c, handling access to GICv3 cpu interface from the guest requires vgic_v3.vgic_sre to be already defined. It is how support has been done: * handle SGI requests from the guest * report configured SRE on access to GICv3 cpu interface from the guest * required vgic-v3 macros are provided via uapi.h * static keys are used to select GIC backend * to make vgic-v3 build KVM_ARM_VGIC_V3 guard is removed along with the static inlines Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22KVM: arm: vgic: Support 64-bit data manipulation on 32-bit host systemsVladimir Murzin
We have couple of 64-bit registers defined in GICv3 architecture, so unsigned long accesses to these registers will only access a single 32-bit part of that regitser. On the other hand these registers can't be accessed as 64-bit with a single instruction like ldrd/strd or ldmia/stmia if we run a 32-bit host because KVM does not support access to MMIO space done by these instructions. It means that a 32-bit guest accesses these registers in 32-bit chunks, so the only thing we need to do is to ensure that extract_bytes() always takes 64-bit data. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22KVM: arm: vgic: Fix compiler warnings when built for 32-bitVladimir Murzin
Well, this patch is looking ahead of time, but we'll get following compiler warnings as soon as we introduce vgic-v3 to 32-bit world CC arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.o arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c: In function 'vgic_mmio_read_v3r_typer': arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c:184:35: warning: left shift count >= width of type [-Wshift-count-overflow] value = (mpidr & GENMASK(23, 0)) << 32; ^ In file included from ./include/linux/kernel.h:10:0, from ./include/asm-generic/bug.h:13, from ./arch/arm/include/asm/bug.h:59, from ./include/linux/bug.h:4, from ./include/linux/io.h:23, from ./arch/arm/include/asm/arch_gicv3.h:23, from ./include/linux/irqchip/arm-gic-v3.h:411, from arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c:14: arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c: In function 'vgic_v3_dispatch_sgi': ./include/linux/bitops.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow] #define BIT(nr) (1UL << (nr)) ^ arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c:614:20: note: in expansion of macro 'BIT' broadcast = reg & BIT(ICC_SGI1R_IRQ_ROUTING_MODE_BIT); ^ Let's fix them now. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22KVM: arm64: vgic-its: Introduce config option to guard ITS specific codeVladimir Murzin
By now ITS code guarded with KVM_ARM_VGIC_V3 config option which was introduced to hide everything specific to vgic-v3 from 32-bit world. We are going to support vgic-v3 in 32-bit world and KVM_ARM_VGIC_V3 will gone, but we don't have support for ITS there yet and we need to continue keeping ITS away. Introduce the new config option to prevent ITS code being build in 32-bit mode when support for vgic-v3 is done. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22arm64: KVM: Move vgic-v3 save/restore to virt/kvm/arm/hypVladimir Murzin
So we can reuse the code under arch/arm Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22arm64: KVM: Use static keys for selecting the GIC backendVladimir Murzin
Currently GIC backend is selected via alternative framework and this is fine. We are going to introduce vgic-v3 to 32-bit world and there we don't have patching framework in hand, so we can either check support for GICv3 every time we need to choose which backend to use or try to optimise it by using static keys. The later looks quite promising because we can share logic involved in selecting GIC backend between architectures if both uses static keys. This patch moves arm64 from alternative to static keys framework for selecting GIC backend. For that we embed static key into vgic_global and enable the key during vgic initialisation based on what has already been exposed by the host GIC driver. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08KVM: ARM: cleanup kvm_timer_hyp_initPaolo Bonzini
Remove two unnecessary labels now that kvm_timer_hyp_init is not creating its own workqueue anymore. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08arm64: KVM: Inject a vSerror if detecting a bad GICV access at EL2Marc Zyngier
If, when proxying a GICV access at EL2, we detect that the guest is doing something silly, report an EL1 SError instead ofgnoring the access. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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 GICV access from HYPMarc Zyngier
Now that we have the necessary infrastructure to handle MMIO accesses in HYP, perform the GICV access on behalf of the guest. This requires checking that the access is strictly 32bit, properly aligned, and falls within the expected range. When all condition are satisfied, we perform the access and tell the rest of the HYP code that the instruction has been correctly emulated. 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>
2016-09-08arm64: KVM: Make kvm_skip_instr32 available to HYPMarc Zyngier
As we plan to do some emulation at HYP, let's make kvm_skip_instr32 as part of the hyp_text section. This doesn't preclude the kernel from using it. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08arm: KVM: Use common AArch32 conditional execution codeMarc Zyngier
Add the bit of glue and const-ification that is required to use the code inherited from the arm64 port, and move over to it. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08arm64: KVM: Move the AArch32 conditional execution to common codeMarc Zyngier
It would make some sense to share the conditional execution code between 32 and 64bit. In order to achieve this, let's move that code to virt/kvm/arm/aarch32.c. While we're at it, drop a superfluous BUG_ON() that wasn't that useful. Following patches will migrate the 32bit port to that code base. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08KVM: arm: vgic: Drop build compatibility hack for older kernel versionsMarc Zyngier
As kvm_set_routing_entry() was changing prototype between 4.7 and 4.8, an ugly hack was put in place in order to survive both building in -next and the merge window. Now that everything has been merged, let's dump the compatibility hack for good. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08KVM: arm/arm64: Rename vgic_attr_regs_access to vgic_attr_regs_access_v2Christoffer Dall
Just a rename so we can implement a v3-specific function later. We take the chance to get rid of the V2/V3 ops comments as well. No functional change. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2016-09-08KVM: arm/arm64: Factor out vgic_attr_regs_access functionalityChristoffer Dall
As we are about to deal with multiple data types and situations where the vgic should not be initialized when doing userspace accesses on the register attributes, factor out the functionality of vgic_attr_regs_access into smaller bits which can be reused by a new function later. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2016-09-07KVM: Remove deprecated create_singlethread_workqueueBhaktipriya Shridhar
The workqueue "irqfd_cleanup_wq" queues a single work item &irqfd->shutdown and hence doesn't require ordering. It is a host-wide workqueue for issuing deferred shutdown requests aggregated from all vm* instances. It is not being used on a memory reclaim path. Hence, it has been converted to use system_wq. The work item has been flushed in kvm_irqfd_release(). The workqueue "wqueue" queues a single work item &timer->expired and hence doesn't require ordering. Also, it is not being used on a memory reclaim path. Hence, it has been converted to use system_wq. System workqueues have been able to handle high level of concurrency for a long time now and hence it's not required to have a singlethreaded workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue created with create_singlethread_workqueue(), system_wq allows multiple work items to overlap executions even on the same CPU; however, a per-cpu workqueue doesn't have any CPU locality or global ordering guarantee unless the target CPU is explicitly specified and thus the increase of local concurrency shouldn't make any difference. Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-08-18Merge tag 'kvm-arm-for-v4.8-rc3' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/ARM Fixes for v4.8-rc3 This tag contains the following fixes on top of v4.8-rc1: - ITS init issues - ITS error handling issues - ITS IRQ leakage fix - Plug a couple of ITS race conditions - An erratum workaround for timers - Some removal of misleading use of errors and comments - A fix for GICv3 on 32-bit guests
2016-08-17KVM: arm/arm64: timer: Workaround misconfigured timer interruptMarc Zyngier
Similarily to f005bd7e3b84 ("clocksource/arm_arch_timer: Force per-CPU interrupt to be level-triggered"), make sure we can survive an interrupt that has been misconfigured as edge-triggered by forcing it to be level-triggered (active low is assumed, but the GIC doesn't really care whether this is high or low). Hopefully, the amount of shouting in the kernel log will convince the user to do something about their firmware. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-16KVM: arm64: ITS: avoid re-mapping LPIsAndre Przywara
When a guest wants to map a device-ID/event-ID combination that is already mapped, we may end up in a situation where an LPI is never "put", thus never being freed. Since the GICv3 spec says that mapping an already mapped LPI is UNPREDICTABLE, lets just bail out early in this situation to avoid any potential leaks. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-15KVM: arm64: check for ITS device on MSI injectionAndre Przywara
When userspace provides the doorbell address for an MSI to be injected into the guest, we find a KVM device which feels responsible. Lets check that this device is really an emulated ITS before we make real use of the container_of-ed pointer. [ Moved NULL-pointer check to caller of static function - Christoffer ] Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-15KVM: arm64: ITS: move ITS registration into first VCPU runAndre Przywara
Currently we register an ITS device upon userland issuing the CTLR_INIT ioctl to mark initialization of the ITS as done. This deviates from the initialization sequence of the existing GIC devices and does not play well with the way QEMU handles things. To be more in line with what we are used to, register the ITS(es) just before the first VCPU is about to run, so in the map_resources() call. This involves iterating through the list of KVM devices and map each ITS that we find. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Tested-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-15KVM: arm64: vgic-its: Make updates to propbaser/pendbaser atomicChristoffer Dall
There are two problems with the current implementation of the MMIO handlers for the propbaser and pendbaser: First, the write to the value itself is not guaranteed to be an atomic 64-bit write so two concurrent writes to the structure field could be intermixed. Second, because we do a read-modify-update operation without any synchronization, if we have two 32-bit accesses to separate parts of the register, we can loose one of them. By using the atomic cmpxchg64 we should cover both issues above. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-12KVM: Protect device ops->create and list_add with kvm->lockChristoffer Dall
KVM devices were manipulating list data structures without any form of synchronization, and some implementations of the create operations also suffered from a lack of synchronization. Now when we've split the xics create operation into create and init, we can hold the kvm->lock mutex while calling the create operation and when manipulating the devices list. The error path in the generic code gets slightly ugly because we have to take the mutex again and delete the device from the list, but holding the mutex during anon_inode_getfd or releasing/locking the mutex in the common non-error path seemed wrong. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-10KVM: arm64: vgic-its: Plug race in vgic_put_irqChristoffer Dall
Right now the following sequence of events can happen: 1. Thread X calls vgic_put_irq 2. Thread Y calls vgic_add_lpi 3. Thread Y gets lpi_list_lock 4. Thread X drops the ref count to 0 and blocks on lpi_list_lock 5. Thread Y finds the irq via the lpi_list_lock, raises the ref count to 1, and release the lpi_list_lock. 6. Thread X proceeds and frees the irq. Avoid this by holding the spinlock around the kref_put. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-10KVM: arm64: vgic-its: Handle errors from vgic_add_lpiChristoffer Dall
During low memory conditions, we could be dereferencing a NULL pointer when vgic_add_lpi fails to allocate memory. Consider for example this call sequence: vgic_its_cmd_handle_mapi itte->irq = vgic_add_lpi(kvm, lpi_nr); update_lpi_config(kvm, itte->irq, NULL); ret = kvm_read_guest(kvm, propbase + irq->intid ^^^^ kaboom? Instead, return an error pointer from vgic_add_lpi and check the return value from its single caller. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-09KVM: arm64: ITS: return 1 on successful MSI injectionAndre Przywara
According to the KVM API documentation a successful MSI injection should return a value > 0 on success. Return possible errors in vgic_its_trigger_msi() and report a successful injection back to userland, while also reporting the case where the MSI could not be delivered due to the guest not having the LPI mapped, for instance. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-04Merge tag 'kvm-arm-for-4.8-take2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/ARM Changes for v4.8 - Take 2 Includes GSI routing support to go along with the new VGIC and a small fix that has been cooking in -next for a while.
2016-08-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: - ARM: GICv3 ITS emulation and various fixes. Removal of the old VGIC implementation. - s390: support for trapping software breakpoints, nested virtualization (vSIE), the STHYI opcode, initial extensions for CPU model support. - MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups, preliminary to this and the upcoming support for hardware virtualization extensions. - x86: support for execute-only mappings in nested EPT; reduced vmexit latency for TSC deadline timer (by about 30%) on Intel hosts; support for more than 255 vCPUs. - PPC: bugfixes. * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits) KVM: PPC: Introduce KVM_CAP_PPC_HTM MIPS: Select HAVE_KVM for MIPS64_R{2,6} MIPS: KVM: Reset CP0_PageMask during host TLB flush MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX() MIPS: KVM: Sign extend MFC0/RDHWR results MIPS: KVM: Fix 64-bit big endian dynamic translation MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase MIPS: KVM: Use 64-bit CP0_EBase when appropriate MIPS: KVM: Set CP0_Status.KX on MIPS64 MIPS: KVM: Make entry code MIPS64 friendly MIPS: KVM: Use kmap instead of CKSEG0ADDR() MIPS: KVM: Use virt_to_phys() to get commpage PFN MIPS: Fix definition of KSEGX() for 64-bit KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD kvm: x86: nVMX: maintain internal copy of current VMCS KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures KVM: arm64: vgic-its: Simplify MAPI error handling KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers KVM: arm64: vgic-its: Turn device_id validation into generic ID validation ...
2016-07-24KVM: arm: vgic-irqfd: Workaround changing kvm_set_routing_entry prototypeMarc Zyngier
kvm_set_routing_entry is changing in -next, and causes things to explode. Add a temporary workaround that should be dropped when we hit 4.8-rc1 Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-22KVM: arm/arm64: Enable MSI routingEric Auger
Up to now, only irqchip routing entries could be set. This patch adds the capability to insert MSI routing entries. For ARM64, let's also increase KVM_MAX_IRQ_ROUTES to 4096: this include SPI irqchip routes plus MSI routes. In the future this might be extended. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-22KVM: arm/arm64: Enable irqchip routingEric Auger
This patch adds compilation and link against irqchip. Main motivation behind using irqchip code is to enable MSI routing code. In the future irqchip routing may also be useful when targeting multiple irqchips. Routing standard callbacks now are implemented in vgic-irqfd: - kvm_set_routing_entry - kvm_set_irq - kvm_set_msi They only are supported with new_vgic code. Both HAVE_KVM_IRQCHIP and HAVE_KVM_IRQ_ROUTING are defined. KVM_CAP_IRQ_ROUTING is advertised and KVM_SET_GSI_ROUTING is allowed. So from now on IRQCHIP routing is enabled and a routing table entry must exist for irqfd injection to succeed for a given SPI. This patch builds a default flat irqchip routing table (gsi=irqchip.pin) covering all the VGIC SPI indexes. This routing table is overwritten by the first first user-space call to KVM_SET_GSI_ROUTING ioctl. MSI routing setup is not yet allowed. Signed-off-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm64: vgic-its: Simplify MAPI error handlingMarc Zyngier
If we care to move all the checks that do not involve any memory allocation, we can simplify the MAPI error handling. Let's do that, it cannot hurt. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlersMarc Zyngier
vgic_its_cmd_handle_mapi has an extra "subcmd" argument, which is already contained in the command buffer that all command handlers obtain from the command queue. Let's drop it, as it is not that useful. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm64: vgic-its: Turn device_id validation into generic ID validationMarc Zyngier
There is no need to have separate functions to validate devices and collections, as the architecture doesn't really distinguish the two, and they are supposed to be managed the same way. Let's turn the DevID checker into a generic one. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm64: vgic-its: Add pointer to corresponding kvm_deviceMarc Zyngier
Going from the ITS structure to the corresponding KVM structure would be quite handy at times. The kvm_device pointer that is passed at create time is quite convenient for this, so let's keep a copy of it in the vgic_its structure. This will be put to a good use in subsequent patches. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm64: vgic-its: Add collection allocator/destructorMarc Zyngier
Instead of spreading random allocations all over the place, consolidate allocation/init/freeing of collections in a pair of constructor/destructor. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18KVM: arm64: vgic-its: Fix L2 entry validation for indirect tablesMarc Zyngier
When checking that the storage address of a device entry is valid, it is critical to compute the actual address of the entry, rather than relying on the beginning of the page to match a CPU page of the same size: for example, if the guest places the table at the last 64kB boundary of RAM, but RAM size isn't a multiple of 64kB... Fix this by computing the actual offset of the device ID in the L2 page, and check the corresponding GFN. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>