diff options
Diffstat (limited to 'virt')
-rw-r--r-- | virt/kvm/arm/vgic/vgic-its.c | 109 | ||||
-rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio.c | 32 | ||||
-rw-r--r-- | virt/kvm/arm/vgic/vgic-v3.c | 5 | ||||
-rw-r--r-- | virt/kvm/eventfd.c | 3 | ||||
-rw-r--r-- | virt/kvm/kvm_main.c | 44 |
5 files changed, 126 insertions, 67 deletions
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 571b64a01c50..8d1da1af4b09 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -360,29 +360,6 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) return ret; } -static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu, - struct vgic_its *its, - gpa_t addr, unsigned int len) -{ - u32 reg = 0; - - mutex_lock(&its->cmd_lock); - if (its->creadr == its->cwriter) - reg |= GITS_CTLR_QUIESCENT; - if (its->enabled) - reg |= GITS_CTLR_ENABLE; - mutex_unlock(&its->cmd_lock); - - return reg; -} - -static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its, - gpa_t addr, unsigned int len, - unsigned long val) -{ - its->enabled = !!(val & GITS_CTLR_ENABLE); -} - static unsigned long vgic_mmio_read_its_typer(struct kvm *kvm, struct vgic_its *its, gpa_t addr, unsigned int len) @@ -1161,33 +1138,16 @@ static void vgic_mmio_write_its_cbaser(struct kvm *kvm, struct vgic_its *its, #define ITS_CMD_SIZE 32 #define ITS_CMD_OFFSET(reg) ((reg) & GENMASK(19, 5)) -/* - * By writing to CWRITER the guest announces new commands to be processed. - * To avoid any races in the first place, we take the its_cmd lock, which - * protects our ring buffer variables, so that there is only one user - * per ITS handling commands at a given time. - */ -static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, - gpa_t addr, unsigned int len, - unsigned long val) +/* Must be called with the cmd_lock held. */ +static void vgic_its_process_commands(struct kvm *kvm, struct vgic_its *its) { gpa_t cbaser; u64 cmd_buf[4]; - u32 reg; - if (!its) - return; - - mutex_lock(&its->cmd_lock); - - reg = update_64bit_reg(its->cwriter, addr & 7, len, val); - reg = ITS_CMD_OFFSET(reg); - if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { - mutex_unlock(&its->cmd_lock); + /* Commands are only processed when the ITS is enabled. */ + if (!its->enabled) return; - } - its->cwriter = reg; cbaser = CBASER_ADDRESS(its->cbaser); while (its->cwriter != its->creadr) { @@ -1207,6 +1167,34 @@ static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, if (its->creadr == ITS_CMD_BUFFER_SIZE(its->cbaser)) its->creadr = 0; } +} + +/* + * By writing to CWRITER the guest announces new commands to be processed. + * To avoid any races in the first place, we take the its_cmd lock, which + * protects our ring buffer variables, so that there is only one user + * per ITS handling commands at a given time. + */ +static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u64 reg; + + if (!its) + return; + + mutex_lock(&its->cmd_lock); + + reg = update_64bit_reg(its->cwriter, addr & 7, len, val); + reg = ITS_CMD_OFFSET(reg); + if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { + mutex_unlock(&its->cmd_lock); + return; + } + its->cwriter = reg; + + vgic_its_process_commands(kvm, its); mutex_unlock(&its->cmd_lock); } @@ -1287,6 +1275,39 @@ static void vgic_mmio_write_its_baser(struct kvm *kvm, *regptr = reg; } +static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu, + struct vgic_its *its, + gpa_t addr, unsigned int len) +{ + u32 reg = 0; + + mutex_lock(&its->cmd_lock); + if (its->creadr == its->cwriter) + reg |= GITS_CTLR_QUIESCENT; + if (its->enabled) + reg |= GITS_CTLR_ENABLE; + mutex_unlock(&its->cmd_lock); + + return reg; +} + +static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its, + gpa_t addr, unsigned int len, + unsigned long val) +{ + mutex_lock(&its->cmd_lock); + + its->enabled = !!(val & GITS_CTLR_ENABLE); + + /* + * Try to process any pending commands. This function bails out early + * if the ITS is disabled or no commands have been queued. + */ + vgic_its_process_commands(kvm, its); + + mutex_unlock(&its->cmd_lock); +} + #define REGISTER_ITS_DESC(off, rd, wr, length, acc) \ { \ .reg_offset = off, \ diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c index 3654b4c835ef..2a5db1352722 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.c +++ b/virt/kvm/arm/vgic/vgic-mmio.c @@ -180,21 +180,37 @@ unsigned long vgic_mmio_read_active(struct kvm_vcpu *vcpu, static void vgic_mmio_change_active(struct kvm_vcpu *vcpu, struct vgic_irq *irq, bool new_active_state) { + struct kvm_vcpu *requester_vcpu; spin_lock(&irq->irq_lock); + + /* + * The vcpu parameter here can mean multiple things depending on how + * this function is called; when handling a trap from the kernel it + * depends on the GIC version, and these functions are also called as + * part of save/restore from userspace. + * + * Therefore, we have to figure out the requester in a reliable way. + * + * When accessing VGIC state from user space, the requester_vcpu is + * NULL, which is fine, because we guarantee that no VCPUs are running + * when accessing VGIC state from user space so irq->vcpu->cpu is + * always -1. + */ + requester_vcpu = kvm_arm_get_running_vcpu(); + /* * If this virtual IRQ was written into a list register, we * have to make sure the CPU that runs the VCPU thread has - * synced back LR state to the struct vgic_irq. We can only - * know this for sure, when either this irq is not assigned to - * anyone's AP list anymore, or the VCPU thread is not - * running on any CPUs. + * synced back the LR state to the struct vgic_irq. * - * In the opposite case, we know the VCPU thread may be on its - * way back from the guest and still has to sync back this - * IRQ, so we release and re-acquire the spin_lock to let the - * other thread sync back the IRQ. + * As long as the conditions below are true, we know the VCPU thread + * may be on its way back from the guest (we kicked the VCPU thread in + * vgic_change_active_prepare) and still has to sync back this IRQ, + * so we release and re-acquire the spin_lock to let the other thread + * sync back the IRQ. */ while (irq->vcpu && /* IRQ may have state in an LR somewhere */ + irq->vcpu != requester_vcpu && /* Current thread is not the VCPU thread */ irq->vcpu->cpu != -1) /* VCPU thread is running */ cond_resched_lock(&irq->irq_lock); diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index edc6ee2dc852..be0f4c3e0142 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -229,10 +229,13 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu) /* * If we are emulating a GICv3, we do it in an non-GICv2-compatible * way, so we force SRE to 1 to demonstrate this to the guest. + * Also, we don't support any form of IRQ/FIQ bypass. * This goes with the spec allowing the value to be RAO/WI. */ if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) { - vgic_v3->vgic_sre = ICC_SRE_EL1_SRE; + vgic_v3->vgic_sre = (ICC_SRE_EL1_DIB | + ICC_SRE_EL1_DFB | + ICC_SRE_EL1_SRE); vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE; } else { vgic_v3->vgic_sre = 0; diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index a29786dd9522..4d28a9ddbee0 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -870,7 +870,8 @@ kvm_deassign_ioeventfd_idx(struct kvm *kvm, enum kvm_bus bus_idx, continue; kvm_io_bus_unregister_dev(kvm, bus_idx, &p->dev); - kvm->buses[bus_idx]->ioeventfd_count--; + if (kvm->buses[bus_idx]) + kvm->buses[bus_idx]->ioeventfd_count--; ioeventfd_release(p); ret = 0; break; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a17d78759727..88257b311cb5 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -727,8 +727,11 @@ static void kvm_destroy_vm(struct kvm *kvm) list_del(&kvm->vm_list); spin_unlock(&kvm_lock); kvm_free_irq_routing(kvm); - for (i = 0; i < KVM_NR_BUSES; i++) - kvm_io_bus_destroy(kvm->buses[i]); + for (i = 0; i < KVM_NR_BUSES; i++) { + if (kvm->buses[i]) + kvm_io_bus_destroy(kvm->buses[i]); + kvm->buses[i] = NULL; + } kvm_coalesced_mmio_free(kvm); #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER) mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm); @@ -1062,7 +1065,7 @@ int __kvm_set_memory_region(struct kvm *kvm, * changes) is disallowed above, so any other attribute changes getting * here can be skipped. */ - if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) { + if (as_id == 0 && (change == KVM_MR_CREATE || change == KVM_MR_MOVE)) { r = kvm_iommu_map_pages(kvm, &new); return r; } @@ -3474,6 +3477,8 @@ int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr, }; bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu); + if (!bus) + return -ENOMEM; r = __kvm_io_bus_write(vcpu, bus, &range, val); return r < 0 ? r : 0; } @@ -3491,6 +3496,8 @@ int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, }; bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu); + if (!bus) + return -ENOMEM; /* First try the device referenced by cookie. */ if ((cookie >= 0) && (cookie < bus->dev_count) && @@ -3541,6 +3548,8 @@ int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr, }; bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu); + if (!bus) + return -ENOMEM; r = __kvm_io_bus_read(vcpu, bus, &range, val); return r < 0 ? r : 0; } @@ -3553,6 +3562,9 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, struct kvm_io_bus *new_bus, *bus; bus = kvm->buses[bus_idx]; + if (!bus) + return -ENOMEM; + /* exclude ioeventfd which is limited by maximum fd */ if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1) return -ENOSPC; @@ -3572,37 +3584,41 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, } /* Caller must hold slots_lock. */ -int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, - struct kvm_io_device *dev) +void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, + struct kvm_io_device *dev) { - int i, r; + int i; struct kvm_io_bus *new_bus, *bus; bus = kvm->buses[bus_idx]; - r = -ENOENT; + if (!bus) + return; + for (i = 0; i < bus->dev_count; i++) if (bus->range[i].dev == dev) { - r = 0; break; } - if (r) - return r; + if (i == bus->dev_count) + return; new_bus = kmalloc(sizeof(*bus) + ((bus->dev_count - 1) * sizeof(struct kvm_io_range)), GFP_KERNEL); - if (!new_bus) - return -ENOMEM; + if (!new_bus) { + pr_err("kvm: failed to shrink bus, removing it completely\n"); + goto broken; + } memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range)); new_bus->dev_count--; memcpy(new_bus->range + i, bus->range + i + 1, (new_bus->dev_count - i) * sizeof(struct kvm_io_range)); +broken: rcu_assign_pointer(kvm->buses[bus_idx], new_bus); synchronize_srcu_expedited(&kvm->srcu); kfree(bus); - return r; + return; } struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, @@ -3615,6 +3631,8 @@ struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, srcu_idx = srcu_read_lock(&kvm->srcu); bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu); + if (!bus) + goto out_unlock; dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1); if (dev_idx < 0) |