From: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx>
This command enables/disables vCPU introspection events.
By default, all events are disabled.
Signed-off-by: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx>
Co-developed-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
---
Documentation/virt/kvm/kvmi.rst | 52 +++++++++++-
include/linux/kvmi_host.h | 2 +
include/uapi/linux/kvmi.h | 26 +++---
.../testing/selftests/kvm/x86_64/kvmi_test.c | 81 +++++++++++++++++++
virt/kvm/introspection/kvmi.c | 15 +++-
virt/kvm/introspection/kvmi_int.h | 3 +
virt/kvm/introspection/kvmi_msg.c | 49 ++++++++---
7 files changed, 205 insertions(+), 23 deletions(-)
diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst
index d841d266b1a9..b0eb2649b10c 100644
--- a/Documentation/virt/kvm/kvmi.rst
+++ b/Documentation/virt/kvm/kvmi.rst
@@ -375,6 +375,9 @@ the following events::
KVMI_EVENT_UNHOOK
+The vCPU events (e.g. *KVMI_EVENT_PAUSE_VCPU*) are controlled with
+the *KVMI_VCPU_CONTROL_EVENTS* command.
+
:Errors:
* -KVM_EINVAL - the padding is not zero
@@ -517,12 +520,59 @@ command) before returning to guest.
* -KVM_EBUSY - the selected vCPU has too many queued *KVMI_EVENT_PAUSE_VCPU* events
* -KVM_EPERM - the *KVMI_EVENT_PAUSE_VCPU* event is disallowed
+10. KVMI_VCPU_CONTROL_EVENTS
+----------------------------
+
+:Architectures: all
+:Versions: >= 1
+:Parameters:
+
+::
+
+ struct kvmi_vcpu_hdr;
+ struct kvmi_vcpu_control_events {
+ __u16 event_id;
+ __u8 enable;
+ __u8 padding1;
+ __u32 padding2;
+ };
+
+:Returns:
+
+::
+
+ struct kvmi_error_code
+
+Enables/disables vCPU introspection events.
+
+When an event is enabled, the introspection tool is notified and
+must reply with: continue, retry, crash, etc. (see **Events** below).
+
+The following vCPU events do not need to be enabled or disabled,
+because these are sent as a result of certain commands::
+
+ KVMI_EVENT_PAUSE_VCPU
+
+However, the events mentioned above can be disallowed.
+
+The VM events (e.g. *KVMI_EVENT_UNHOOK*) are controlled with
+the *KVMI_VM_CONTROL_EVENTS* command.
+
+:Errors:
+
+* -KVM_EINVAL - the padding is not zero
+* -KVM_EINVAL - the selected vCPU is invalid
+* -KVM_EINVAL - the event ID is unknown (use *KVMI_VM_CHECK_EVENT* first)
+* -KVM_EPERM - the access is disallowed (use *KVMI_VM_CHECK_EVENT* first)
+* -KVM_EAGAIN - the selected vCPU can't be introspected yet
+
Events
======
All introspection events (VM or vCPU related) are sent
using the *KVMI_EVENT* message id. No event will be sent unless
-it is explicitly enabled or requested (eg. *KVMI_EVENT_PAUSE_VCPU*).
+it is explicitly enabled (see *KVMI_VM_CONTROL_EVENTS* and *KVMI_VCPU_CONTROL_EVENTS*)
+or requested (eg. *KVMI_EVENT_PAUSE_VCPU*).
The *KVMI_EVENT_UNHOOK* event doesn't have a reply and share the kvmi_event
structure, for consistency with the vCPU events.
diff --git a/include/linux/kvmi_host.h b/include/linux/kvmi_host.h
index 49e68777a390..8e8ab9d836fe 100644
--- a/include/linux/kvmi_host.h
+++ b/include/linux/kvmi_host.h
@@ -36,6 +36,8 @@ struct kvm_vcpu_introspection {
struct kvmi_vcpu_reply reply;
bool waiting_for_reply;
+
+ DECLARE_BITMAP(ev_enable_mask, KVMI_NUM_EVENTS);
};
struct kvm_introspection {
diff --git a/include/uapi/linux/kvmi.h b/include/uapi/linux/kvmi.h
index e6a4667546b5..e361d6e6563d 100644
--- a/include/uapi/linux/kvmi.h
+++ b/include/uapi/linux/kvmi.h
@@ -17,16 +17,17 @@ enum {
enum {
KVMI_EVENT = 1,
- KVMI_GET_VERSION = 2,
- KVMI_VM_CHECK_COMMAND = 3,
- KVMI_VM_CHECK_EVENT = 4,
- KVMI_VM_GET_INFO = 5,
- KVMI_VM_CONTROL_EVENTS = 6,
- KVMI_VM_READ_PHYSICAL = 7,
- KVMI_VM_WRITE_PHYSICAL = 8,
+ KVMI_GET_VERSION = 2,
+ KVMI_VM_CHECK_COMMAND = 3,
+ KVMI_VM_CHECK_EVENT = 4,
+ KVMI_VM_GET_INFO = 5,
+ KVMI_VM_CONTROL_EVENTS = 6,
+ KVMI_VM_READ_PHYSICAL = 7,
+ KVMI_VM_WRITE_PHYSICAL = 8,
- KVMI_VCPU_GET_INFO = 9,
- KVMI_VCPU_PAUSE = 10,
+ KVMI_VCPU_GET_INFO = 9,
+ KVMI_VCPU_PAUSE = 10,
+ KVMI_VCPU_CONTROL_EVENTS = 11,
KVMI_NUM_MESSAGES
};
@@ -123,6 +124,13 @@ struct kvmi_vcpu_pause {
__u32 padding3;
};
+struct kvmi_vcpu_control_events {
+ __u16 event_id;
+ __u8 enable;
+ __u8 padding1;
+ __u32 padding2;
+};
+
struct kvmi_event {
__u16 size;
__u16 vcpu;
diff --git a/tools/testing/selftests/kvm/x86_64/kvmi_test.c b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
index 990c78a7af0a..94378066d69a 100644
--- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
@@ -97,6 +97,11 @@ static void toggle_event_permission(struct kvm_vm *vm, __s32 id, bool allow)
id, errno, strerror(errno));
}
+static void disallow_event(struct kvm_vm *vm, __s32 event_id)
+{
+ toggle_event_permission(vm, event_id, false);
+}
+
static void allow_event(struct kvm_vm *vm, __s32 event_id)
{
toggle_event_permission(vm, event_id, true);
@@ -727,6 +732,81 @@ static void test_pause(struct kvm_vm *vm)
stop_vcpu_worker(vcpu_thread, &data);
}
+static int cmd_vcpu_control_event(struct kvm_vm *vm, __u16 event_id,
+ bool enable)
+{
+ struct {
+ struct kvmi_msg_hdr hdr;
+ struct kvmi_vcpu_hdr vcpu_hdr;
+ struct kvmi_vcpu_control_events cmd;
+ } req = {};
+
+ req.cmd.event_id = event_id;
+ req.cmd.enable = enable ? 1 : 0;
+
+ return do_vcpu0_command(vm, KVMI_VCPU_CONTROL_EVENTS,
+ &req.hdr, sizeof(req), NULL, 0);
+}
+
+static void enable_vcpu_event(struct kvm_vm *vm, __u16 event_id)
+{
+ int r;
+
+ r = cmd_vcpu_control_event(vm, event_id, true);
+ TEST_ASSERT(r == 0,
+ "KVMI_VCPU_CONTROL_EVENTS failed to enable vCPU event %d, error %d(%s)\n",
+ event_id, -r, kvm_strerror(-r));
+}
+
+static void disable_vcpu_event(struct kvm_vm *vm, __u16 event_id)
+{
+ int r;
+
+ r = cmd_vcpu_control_event(vm, event_id, false);
+ TEST_ASSERT(r == 0,
+ "KVMI_VCPU_CONTROL_EVENTS failed to disable vCPU event %d, error %d(%s)\n",
+ event_id, -r, kvm_strerror(-r));
+}
+
+static void test_disallowed_vcpu_event(struct kvm_vm *vm, __u16 event_id)
+{
+ bool enable = true;
+ int r;
+
+ disallow_event(vm, event_id);
+
+ r = cmd_vcpu_control_event(vm, event_id, enable);
+ TEST_ASSERT(r == -KVM_EPERM,
+ "KVMI_VCPU_CONTROL_EVENTS didn't failed with KVM_EPERM, id %d, error %d (%s)\n",
+ event_id, -r, kvm_strerror(-r));
+
+ allow_event(vm, event_id);
+}
+
+static void test_invalid_vcpu_event(struct kvm_vm *vm, __u16 event_id)
+{
+ bool enable = true;
+ int r;
+
+ r = cmd_vcpu_control_event(vm, event_id, enable);
+ TEST_ASSERT(r == -KVM_EINVAL,
+ "cmd_vcpu_control_event didn't failed with KVM_EINVAL, id %d, error %d (%s)\n",
+ event_id, -r, kvm_strerror(-r));
+}
+
+static void test_cmd_vcpu_control_events(struct kvm_vm *vm)
+{
+ __u16 valid_id = KVMI_EVENT_PAUSE_VCPU;
+ __u16 invalid_id = 0xffff;
+
+ enable_vcpu_event(vm, valid_id);
+ disable_vcpu_event(vm, valid_id);
+
+ test_disallowed_vcpu_event(vm, valid_id);
+
+ test_invalid_vcpu_event(vm, invalid_id);
+}
+
static void test_introspection(struct kvm_vm *vm)
{
srandom(time(0));
@@ -743,6 +823,7 @@ static void test_introspection(struct kvm_vm *vm)
test_memory_access(vm);
test_cmd_get_vcpu_info(vm);
test_pause(vm);
+ test_cmd_vcpu_control_events(vm);
unhook_introspection(vm);
}
diff --git a/virt/kvm/introspection/kvmi.c b/virt/kvm/introspection/kvmi.c
index 517e77ab39c2..b6b3efd085c4 100644
--- a/virt/kvm/introspection/kvmi.c
+++ b/virt/kvm/introspection/kvmi.c
@@ -16,7 +16,7 @@
static DECLARE_BITMAP(Kvmi_always_allowed_commands, KVMI_NUM_COMMANDS);
DECLARE_BITMAP(Kvmi_known_events, KVMI_NUM_EVENTS);
DECLARE_BITMAP(Kvmi_known_vm_events, KVMI_NUM_EVENTS);
-static DECLARE_BITMAP(Kvmi_known_vcpu_events, KVMI_NUM_EVENTS);
+DECLARE_BITMAP(Kvmi_known_vcpu_events, KVMI_NUM_EVENTS);
static struct kmem_cache *msg_cache;
static struct kmem_cache *job_cache;
@@ -576,6 +576,19 @@ int kvmi_cmd_vm_control_events(struct kvm_introspection *kvmi,
return 0;
}
+int kvmi_cmd_vcpu_control_events(struct kvm_vcpu *vcpu,
+ unsigned int event_id, bool enable)
+{
+ struct kvm_vcpu_introspection *vcpui = VCPUI(vcpu);
+
+ if (enable)
+ set_bit(event_id, vcpui->ev_enable_mask);
+ else
+ clear_bit(event_id, vcpui->ev_enable_mask);
+
+ return 0;
+}
+
static unsigned long gfn_to_hva_safe(struct kvm *kvm, gfn_t gfn)
{
unsigned long hva;
diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h
index 8fe74b32a5f6..e94356516a05 100644
--- a/virt/kvm/introspection/kvmi_int.h
+++ b/virt/kvm/introspection/kvmi_int.h
@@ -18,6 +18,7 @@
extern DECLARE_BITMAP(Kvmi_known_events, KVMI_NUM_EVENTS);
extern DECLARE_BITMAP(Kvmi_known_vm_events, KVMI_NUM_EVENTS);
+extern DECLARE_BITMAP(Kvmi_known_vcpu_events, KVMI_NUM_EVENTS);
#define KVMI(kvm) ((kvm)->kvmi)
#define VCPUI(vcpu) ((vcpu)->kvmi)
@@ -39,6 +40,8 @@ int kvmi_add_job(struct kvm_vcpu *vcpu,
void kvmi_run_jobs(struct kvm_vcpu *vcpu);
int kvmi_cmd_vm_control_events(struct kvm_introspection *kvmi,
unsigned int event_id, bool enable);
+int kvmi_cmd_vcpu_control_events(struct kvm_vcpu *vcpu,
+ unsigned int event_id, bool enable);
int kvmi_cmd_read_physical(struct kvm *kvm, u64 gpa, size_t size,
int (*send)(struct kvm_introspection *,
const struct kvmi_msg_hdr*,
diff --git a/virt/kvm/introspection/kvmi_msg.c b/virt/kvm/introspection/kvmi_msg.c
index a56926f22bc6..f819d0a942dc 100644
--- a/virt/kvm/introspection/kvmi_msg.c
+++ b/virt/kvm/introspection/kvmi_msg.c
@@ -20,16 +20,17 @@ struct kvmi_vcpu_cmd_job {
};
static const char *const msg_IDs[] = {
- [KVMI_EVENT] = "KVMI_EVENT",
- [KVMI_GET_VERSION] = "KVMI_GET_VERSION",
- [KVMI_VM_CHECK_COMMAND] = "KVMI_VM_CHECK_COMMAND",
- [KVMI_VM_CHECK_EVENT] = "KVMI_VM_CHECK_EVENT",
- [KVMI_VM_CONTROL_EVENTS] = "KVMI_VM_CONTROL_EVENTS",
- [KVMI_VM_GET_INFO] = "KVMI_VM_GET_INFO",
- [KVMI_VM_READ_PHYSICAL] = "KVMI_VM_READ_PHYSICAL",
- [KVMI_VM_WRITE_PHYSICAL] = "KVMI_VM_WRITE_PHYSICAL",
- [KVMI_VCPU_GET_INFO] = "KVMI_VCPU_GET_INFO",
- [KVMI_VCPU_PAUSE] = "KVMI_VCPU_PAUSE",
+ [KVMI_EVENT] = "KVMI_EVENT",
+ [KVMI_GET_VERSION] = "KVMI_GET_VERSION",
+ [KVMI_VM_CHECK_COMMAND] = "KVMI_VM_CHECK_COMMAND",
+ [KVMI_VM_CHECK_EVENT] = "KVMI_VM_CHECK_EVENT",
+ [KVMI_VM_CONTROL_EVENTS] = "KVMI_VM_CONTROL_EVENTS",
+ [KVMI_VM_GET_INFO] = "KVMI_VM_GET_INFO",
+ [KVMI_VM_READ_PHYSICAL] = "KVMI_VM_READ_PHYSICAL",
+ [KVMI_VM_WRITE_PHYSICAL] = "KVMI_VM_WRITE_PHYSICAL",
+ [KVMI_VCPU_CONTROL_EVENTS] = "KVMI_VCPU_CONTROL_EVENTS",
+ [KVMI_VCPU_GET_INFO] = "KVMI_VCPU_GET_INFO",
+ [KVMI_VCPU_PAUSE] = "KVMI_VCPU_PAUSE",
};
static const char *id2str(u16 id)
@@ -442,6 +443,29 @@ static int handle_event_reply(const struct kvmi_vcpu_cmd_job *job,
return expected->error;
}
+static int handle_vcpu_control_events(const struct kvmi_vcpu_cmd_job *job,
+ const struct kvmi_msg_hdr *msg,
+ const void *_req)
+{
+ struct kvm_introspection *kvmi = KVMI(job->vcpu->kvm);
+ const struct kvmi_vcpu_control_events *req = _req;
+ int ec;
+
+ if (req->padding1 || req->padding2 || req->enable > 1)
+ ec = -KVM_EINVAL;
+ else if (req->event_id >= KVMI_NUM_EVENTS)
+ ec = -KVM_EINVAL;
+ else if (!test_bit(req->event_id, Kvmi_known_vcpu_events))
+ ec = -KVM_EINVAL;
+ else if (!is_event_allowed(kvmi, req->event_id))
+ ec = -KVM_EPERM;
+ else
+ ec = kvmi_cmd_vcpu_control_events(job->vcpu, req->event_id,
+ req->enable == 1);
+
+ return kvmi_msg_vcpu_reply(job, msg, ec, NULL, 0);
+}
+
/*
* These commands are executed from the vCPU thread. The receiving thread
* passes the messages using a newly allocated 'struct kvmi_vcpu_cmd_job'
@@ -450,8 +474,9 @@ static int handle_event_reply(const struct kvmi_vcpu_cmd_job *job,
*/
static int(*const msg_vcpu[])(const struct kvmi_vcpu_cmd_job *,
const struct kvmi_msg_hdr *, const void *) = {
- [KVMI_EVENT] = handle_event_reply,
- [KVMI_VCPU_GET_INFO] = handle_get_vcpu_info,
+ [KVMI_EVENT] = handle_event_reply,
+ [KVMI_VCPU_CONTROL_EVENTS] = handle_vcpu_control_events,
+ [KVMI_VCPU_GET_INFO] = handle_get_vcpu_info,
};
static bool is_vcpu_command(u16 id)
