[RFC PATCH v4 09/18] kvm: hook in the VM introspection subsystem

["Adalber Lazăr" <alazar@bitdefender.com>]

From: Adalbert Lazar <alazar@bitdefender.com>

Handle the new KVM_INTROSPECTION ioctl and pass the socket from QEMU to
the KVMI subsystem. Notify KVMI on vCPU create/destroy and VM destroy
events. Also, the EPT AD bits feature is disabled by this patch.

Signed-off-by: Adalbert Lazăr <alazar@bitdefender.com>
---
 arch/x86/kvm/vmx.c  |  3 ++-
 virt/kvm/kvm_main.c | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 093a2e1f7ea6..c03580abf9e8 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -34,6 +34,7 @@
 #include <linux/tboot.h>
 #include <linux/hrtimer.h>
 #include <linux/frame.h>
+#include <linux/kvmi.h>
 #include "kvm_cache_regs.h"
 #include "x86.h"
 
@@ -6785,7 +6786,7 @@ static __init int hardware_setup(void)
 	    !cpu_has_vmx_invept_global())
 		enable_ept = 0;
 
-	if (!cpu_has_vmx_ept_ad_bits() || !enable_ept)
+	if (!cpu_has_vmx_ept_ad_bits() || !enable_ept || kvmi_is_present())
 		enable_ept_ad_bits = 0;
 
 	if (!cpu_has_vmx_unrestricted_guest() || !enable_ept)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 210bf820385a..7895d490bd71 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -51,6 +51,7 @@
 #include <linux/slab.h>
 #include <linux/sort.h>
 #include <linux/bsearch.h>
+#include <linux/kvmi.h>
 
 #include <asm/processor.h>
 #include <asm/io.h>
@@ -298,6 +299,9 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 	r = kvm_arch_vcpu_init(vcpu);
 	if (r < 0)
 		goto fail_free_run;
+
+	kvmi_vcpu_init(vcpu);
+
 	return 0;
 
 fail_free_run:
@@ -315,6 +319,7 @@ void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 	 * descriptors are already gone.
 	 */
 	put_pid(rcu_dereference_protected(vcpu->pid, 1));
+	kvmi_vcpu_uninit(vcpu);
 	kvm_arch_vcpu_uninit(vcpu);
 	free_page((unsigned long)vcpu->run);
 }
@@ -711,6 +716,7 @@ static void kvm_destroy_vm(struct kvm *kvm)
 	int i;
 	struct mm_struct *mm = kvm->mm;
 
+	kvmi_destroy_vm(kvm);
 	kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
 	kvm_destroy_vm_debugfs(kvm);
 	kvm_arch_sync_events(kvm);
@@ -3118,6 +3124,15 @@ static long kvm_vm_ioctl(struct file *filp,
 	case KVM_CHECK_EXTENSION:
 		r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
 		break;
+	case KVM_INTROSPECTION: {
+		struct kvm_introspection i;
+
+		r = -EFAULT;
+		if (copy_from_user(&i, argp, sizeof(i)) || !kvmi_hook(kvm, &i))
+			goto out;
+		r = 0;
+		break;
+	}
 	default:
 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
 	}
@@ -4072,6 +4087,9 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 	r = kvm_vfio_ops_init();
 	WARN_ON(r);
 
+	r = kvmi_init();
+	WARN_ON(r);
+
 	return 0;
 
 out_undebugfs:
@@ -4100,6 +4118,7 @@ EXPORT_SYMBOL_GPL(kvm_init);
 
 void kvm_exit(void)
 {
+	kvmi_uninit();
 	debugfs_remove_recursive(kvm_debugfs_dir);
 	misc_deregister(&kvm_dev);
 	kmem_cache_destroy(kvm_vcpu_cache);