From: Mihai Donțu <[email protected]> The introspection requests (KVM_REQ_INTROSPECTION) are checked before entering guest or when the vCPU is halted.
Signed-off-by: Mihai Donțu <[email protected]> Co-developed-by: Mircea Cîrjaliu <[email protected]> Signed-off-by: Mircea Cîrjaliu <[email protected]> Co-developed-by: Adalbert Lazăr <[email protected]> Signed-off-by: Adalbert Lazăr <[email protected]> --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/x86.c | 3 ++ include/linux/kvm_host.h | 2 + include/linux/kvmi_host.h | 4 ++ virt/kvm/introspection/kvmi.c | 72 +++++++++++++++++++++++++++++++++ virt/kvm/kvm_main.c | 2 + 6 files changed, 84 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 378a094ceb5b..9cf45ca73af5 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -78,6 +78,7 @@ #define KVM_REQ_HV_STIMER KVM_ARCH_REQ(22) #define KVM_REQ_LOAD_EOI_EXITMAP KVM_ARCH_REQ(23) #define KVM_REQ_GET_VMCS12_PAGES KVM_ARCH_REQ(24) +#define KVM_REQ_INTROSPECTION KVM_ARCH_REQ(25) #define CR0_RESERVED_BITS \ (~(unsigned long)(X86_CR0_PE | X86_CR0_MP | X86_CR0_EM | X86_CR0_TS \ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 46aeb32cb07f..46a135595893 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8391,6 +8391,9 @@ static int vcpu_run(struct kvm_vcpu *vcpu) vcpu->arch.l1tf_flush_l1d = true; for (;;) { + if (kvm_check_request(KVM_REQ_INTROSPECTION, vcpu)) + kvmi_handle_requests(vcpu); + if (kvm_vcpu_running(vcpu)) { r = vcpu_enter_guest(vcpu); } else { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 52e98720d0f6..d2d9b814093e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -505,6 +505,8 @@ struct kvm { struct srcu_struct irq_srcu; pid_t userspace_pid; struct mutex kvmi_lock; + refcount_t kvmi_ref; + struct completion kvmi_complete; struct kvm_introspection *kvmi; }; diff --git a/include/linux/kvmi_host.h b/include/linux/kvmi_host.h index 1d80d233fbd5..6a0fb481b192 100644 --- a/include/linux/kvmi_host.h +++ b/include/linux/kvmi_host.h @@ -56,6 +56,8 @@ int kvmi_ioctl_command(struct kvm *kvm, void __user *argp); int kvmi_ioctl_event(struct kvm *kvm, void __user *argp); int kvmi_ioctl_preunhook(struct kvm *kvm); +void kvmi_handle_requests(struct kvm_vcpu *vcpu); + #else static inline int kvmi_init(void) { return 0; } @@ -64,6 +66,8 @@ static inline void kvmi_create_vm(struct kvm *kvm) { } static inline void kvmi_destroy_vm(struct kvm *kvm) { } static inline void kvmi_vcpu_uninit(struct kvm_vcpu *vcpu) { } +static inline void kvmi_handle_requests(struct kvm_vcpu *vcpu) { } + #endif /* CONFIG_KVM_INTROSPECTION */ #endif diff --git a/virt/kvm/introspection/kvmi.c b/virt/kvm/introspection/kvmi.c index 5149f8e06131..ea86512ca81e 100644 --- a/virt/kvm/introspection/kvmi.c +++ b/virt/kvm/introspection/kvmi.c @@ -65,6 +65,12 @@ void kvmi_uninit(void) kvmi_cache_destroy(); } +static void kvmi_make_request(struct kvm_vcpu *vcpu) +{ + kvm_make_request(KVM_REQ_INTROSPECTION, vcpu); + kvm_vcpu_kick(vcpu); +} + static int __kvmi_add_job(struct kvm_vcpu *vcpu, void (*fct)(struct kvm_vcpu *vcpu, void *ctx), void *ctx, void (*free_fct)(void *ctx)) @@ -96,6 +102,9 @@ int kvmi_add_job(struct kvm_vcpu *vcpu, err = __kvmi_add_job(vcpu, fct, ctx, free_fct); + if (!err) + kvmi_make_request(vcpu); + return err; } @@ -217,6 +226,7 @@ static void __kvmi_unhook(struct kvm *kvm) { struct kvm_introspection *kvmi = KVMI(kvm); + wait_for_completion_killable(&kvm->kvmi_complete); kvmi_sock_put(kvmi); } @@ -242,8 +252,23 @@ int kvmi_ioctl_unhook(struct kvm *kvm) return 0; } +struct kvm_introspection * __must_check kvmi_get(struct kvm *kvm) +{ + if (refcount_inc_not_zero(&kvm->kvmi_ref)) + return kvm->kvmi; + + return NULL; +} + +void kvmi_put(struct kvm *kvm) +{ + if (refcount_dec_and_test(&kvm->kvmi_ref)) + complete(&kvm->kvmi_complete); +} + static int __kvmi_hook(struct kvm *kvm, const struct kvm_introspection_hook *hook) + { struct kvm_introspection *kvmi = KVMI(kvm); @@ -266,6 +291,7 @@ static int kvmi_recv_thread(void *arg) */ kvmi_sock_shutdown(kvmi); + kvmi_put(kvmi->kvm); return 0; } @@ -293,9 +319,18 @@ int kvmi_hook(struct kvm *kvm, const struct kvm_introspection_hook *hook) if (err) goto destroy; + init_completion(&kvm->kvmi_complete); + + refcount_set(&kvm->kvmi_ref, 1); + /* + * Paired with refcount_inc_not_zero() from kvmi_get(). + */ + smp_wmb(); + kvmi->recv = kthread_run(kvmi_recv_thread, kvmi, "kvmi-recv"); if (IS_ERR(kvmi->recv)) { err = -ENOMEM; + kvmi_put(kvm); goto unhook; } @@ -616,3 +651,40 @@ int kvmi_cmd_write_physical(struct kvm *kvm, u64 gpa, u64 size, const void *buf) return 0; } + +static struct kvmi_job *kvmi_pull_job(struct kvm_vcpu_introspection *vcpui) +{ + struct kvmi_job *job = NULL; + + spin_lock(&vcpui->job_lock); + job = list_first_entry_or_null(&vcpui->job_list, typeof(*job), link); + if (job) + list_del(&job->link); + spin_unlock(&vcpui->job_lock); + + return job; +} + +void kvmi_run_jobs(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_introspection *vcpui = VCPUI(vcpu); + struct kvmi_job *job; + + while ((job = kvmi_pull_job(vcpui))) { + job->fct(vcpu, job->ctx); + kvmi_free_job(job); + } +} + +void kvmi_handle_requests(struct kvm_vcpu *vcpu) +{ + struct kvm_introspection *kvmi; + + kvmi = kvmi_get(vcpu->kvm); + if (!kvmi) + return; + + kvmi_run_jobs(vcpu); + + kvmi_put(vcpu->kvm); +} diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ef7d14ef8e86..b701254f1125 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2414,6 +2414,8 @@ static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu) goto out; if (signal_pending(current)) goto out; + if (kvm_test_request(KVM_REQ_INTROSPECTION, vcpu)) + goto out; ret = 0; out: _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
