With this command the introspection tool enables/disables VM events (ie. KVMI_EVENT_UNHOOK).
By default, all events are disabled. Signed-off-by: Adalbert Lazăr <[email protected]> --- Documentation/virt/kvm/kvmi.rst | 44 +++++++++++++-- include/linux/kvmi_host.h | 2 + include/uapi/linux/kvmi.h | 18 +++++-- .../testing/selftests/kvm/x86_64/kvmi_test.c | 54 +++++++++++++++++++ virt/kvm/introspection/kvmi.c | 21 +++++++- virt/kvm/introspection/kvmi_int.h | 3 ++ virt/kvm/introspection/kvmi_msg.c | 31 +++++++++-- 7 files changed, 159 insertions(+), 14 deletions(-) diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst index e652bdd65052..7a47fade7f08 100644 --- a/Documentation/virt/kvm/kvmi.rst +++ b/Documentation/virt/kvm/kvmi.rst @@ -340,11 +340,45 @@ This command is always allowed. Returns the number of online vCPUs. +5. KVMI_VM_CONTROL_EVENTS +------------------------- + +:Architectures: all +:Versions: >= 1 +:Parameters: + +:: + + struct kvmi_vm_control_events { + __u16 event_id; + __u8 enable; + __u8 padding1; + __u32 padding2; + }; + +:Returns: + +:: + + struct kvmi_error_code + +Enables/disables VM introspection events. This command can be used with +the following events:: + + KVMI_EVENT_UNHOOK + +:Errors: + +* -KVM_EINVAL - the padding is not zero +* -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) + Events ====== All introspection events (VM or vCPU related) are sent -using the *KVMI_EVENT* message id. +using the *KVMI_EVENT* message id. No event will be sent unless +it is explicitly enabled. The *KVMI_EVENT_UNHOOK* event doesn't have a reply and share the kvmi_event structure, for consistency with the vCPU events. @@ -398,6 +432,8 @@ Specific data can follow these common structures. :Returns: none -This event is sent when the device manager has to pause/stop/migrate the -guest (see **Unhooking**). The introspection tool has a chance to unhook -and close the KVMI channel (signaling that the operation can proceed). +This event is sent when the device manager has to pause/stop/migrate +the guest (see **Unhooking**) and the introspection has been enabled +for this event (see **KVMI_VM_CONTROL_EVENTS**). The introspection tool +has a chance to unhook and close the KVMI channel (signaling that the +operation can proceed). diff --git a/include/linux/kvmi_host.h b/include/linux/kvmi_host.h index 180e26335a8f..41b22af771fb 100644 --- a/include/linux/kvmi_host.h +++ b/include/linux/kvmi_host.h @@ -22,6 +22,8 @@ struct kvm_introspection { DECLARE_BITMAP(cmd_allow_mask, KVMI_NUM_COMMANDS); DECLARE_BITMAP(event_allow_mask, KVMI_NUM_EVENTS); + DECLARE_BITMAP(vm_event_enable_mask, KVMI_NUM_EVENTS); + atomic_t ev_seq; }; diff --git a/include/uapi/linux/kvmi.h b/include/uapi/linux/kvmi.h index 689eba32c031..66e04a82f054 100644 --- a/include/uapi/linux/kvmi.h +++ b/include/uapi/linux/kvmi.h @@ -15,12 +15,13 @@ enum { }; enum { - KVMI_EVENT = 1, + KVMI_EVENT = 1, - KVMI_GET_VERSION = 2, - KVMI_VM_CHECK_COMMAND = 3, - KVMI_VM_CHECK_EVENT = 4, - KVMI_VM_GET_INFO = 5, + 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_NUM_MESSAGES }; @@ -75,6 +76,13 @@ struct kvmi_vm_get_info_reply { __u32 padding[3]; }; +struct kvmi_vm_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 9cb65f8c946f..c3beea3feb26 100644 --- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c +++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c @@ -245,9 +245,15 @@ static int cmd_check_event(__u16 id) static void test_cmd_check_event(void) { + __u16 valid_id = KVMI_EVENT_UNHOOK; __u16 invalid_id = 0xffff; int r; + r = cmd_check_event(valid_id); + TEST_ASSERT(r == 0, + "KVMI_VM_CHECK_EVENT failed, error %d (%s)\n", + -r, kvm_strerror(-r)); + r = cmd_check_event(invalid_id); TEST_ASSERT(r == -KVM_ENOENT, "KVMI_VM_CHECK_EVENT didn't failed with -KVM_ENOENT, error %d (%s)\n", @@ -298,15 +304,62 @@ static void receive_event(struct kvmi_msg_hdr *hdr, struct kvmi_event *ev, ev->event, event_id); } +static int cmd_vm_control_events(__u16 event_id, bool enable) +{ + struct { + struct kvmi_msg_hdr hdr; + struct kvmi_vm_control_events cmd; + } req = {}; + + req.cmd.event_id = event_id; + req.cmd.enable = enable ? 1 : 0; + + return do_command(KVMI_VM_CONTROL_EVENTS, &req.hdr, sizeof(req), + NULL, 0); +} + +static void enable_vm_event(__u16 event_id) +{ + int r; + + r = cmd_vm_control_events(event_id, true); + TEST_ASSERT(r == 0, + "KVMI_VM_CONTROL_EVENTS failed to enable VM event %d, error %d (%s)\n", + event_id, -r, kvm_strerror(-r)); +} + +static void disable_vm_event(__u16 event_id) +{ + int r; + + r = cmd_vm_control_events(event_id, false); + TEST_ASSERT(r == 0, + "KVMI_VM_CONTROL_EVENTS failed to disable VM event %d, error %d (%s)\n", + event_id, -r, kvm_strerror(-r)); +} + static void test_event_unhook(struct kvm_vm *vm) { __u16 id = KVMI_EVENT_UNHOOK; struct kvmi_msg_hdr hdr; struct kvmi_event ev; + enable_vm_event(id); + trigger_event_unhook_notification(vm); receive_event(&hdr, &ev, sizeof(ev), id); + + disable_vm_event(id); +} + +static void test_cmd_vm_control_events(void) +{ + __u16 id = KVMI_EVENT_UNHOOK; + + enable_vm_event(id); + + disable_vm_event(id); } static void test_introspection(struct kvm_vm *vm) @@ -320,6 +373,7 @@ static void test_introspection(struct kvm_vm *vm) test_cmd_check_event(); test_cmd_get_vm_info(); test_event_unhook(vm); + test_cmd_vm_control_events(); unhook_introspection(vm); } diff --git a/virt/kvm/introspection/kvmi.c b/virt/kvm/introspection/kvmi.c index bf6d5ec951c8..ec4515be5acc 100644 --- a/virt/kvm/introspection/kvmi.c +++ b/virt/kvm/introspection/kvmi.c @@ -12,7 +12,7 @@ static DECLARE_BITMAP(Kvmi_always_allowed_commands, KVMI_NUM_COMMANDS); DECLARE_BITMAP(Kvmi_known_events, KVMI_NUM_EVENTS); -static DECLARE_BITMAP(Kvmi_known_vm_events, KVMI_NUM_EVENTS); +DECLARE_BITMAP(Kvmi_known_vm_events, KVMI_NUM_EVENTS); static DECLARE_BITMAP(Kvmi_known_vcpu_events, KVMI_NUM_EVENTS); static struct kmem_cache *msg_cache; @@ -360,10 +360,18 @@ int kvmi_ioctl_command(struct kvm *kvm, void __user *argp) return err; } +static bool is_vm_event_enabled(struct kvm_introspection *kvmi, int event) +{ + return test_bit(event, kvmi->vm_event_enable_mask); +} + static bool kvmi_unhook_event(struct kvm_introspection *kvmi) { int err; + if (!is_vm_event_enabled(kvmi, KVMI_EVENT_UNHOOK)) + return false; + err = kvmi_msg_send_unhook(kvmi); return !err; @@ -389,3 +397,14 @@ int kvmi_ioctl_preunhook(struct kvm *kvm) mutex_unlock(&kvm->kvmi_lock); return err; } + +int kvmi_cmd_vm_control_events(struct kvm_introspection *kvmi, + unsigned int event_id, bool enable) +{ + if (enable) + set_bit(event_id, kvmi->vm_event_enable_mask); + else + clear_bit(event_id, kvmi->vm_event_enable_mask); + + return 0; +} diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h index ecd0625e0c9e..75078248a69c 100644 --- a/virt/kvm/introspection/kvmi_int.h +++ b/virt/kvm/introspection/kvmi_int.h @@ -17,6 +17,7 @@ kvm_info("%pU ERROR: " fmt, &kvmi->uuid, ## __VA_ARGS__) extern DECLARE_BITMAP(Kvmi_known_events, KVMI_NUM_EVENTS); +extern DECLARE_BITMAP(Kvmi_known_vm_events, KVMI_NUM_EVENTS); #define KVMI(kvm) ((kvm)->kvmi) @@ -30,5 +31,7 @@ int kvmi_msg_send_unhook(struct kvm_introspection *kvmi); /* kvmi.c */ void *kvmi_msg_alloc(void); void kvmi_msg_free(void *addr); +int kvmi_cmd_vm_control_events(struct kvm_introspection *kvmi, + unsigned int event_id, bool enable); #endif diff --git a/virt/kvm/introspection/kvmi_msg.c b/virt/kvm/introspection/kvmi_msg.c index b381273b7355..4d897c65085b 100644 --- a/virt/kvm/introspection/kvmi_msg.c +++ b/virt/kvm/introspection/kvmi_msg.c @@ -171,15 +171,38 @@ static int handle_get_info(struct kvm_introspection *kvmi, return kvmi_msg_vm_reply(kvmi, msg, 0, &rpl, sizeof(rpl)); } +static int handle_vm_control_events(struct kvm_introspection *kvmi, + const struct kvmi_msg_hdr *msg, + const void *_req) +{ + const struct kvmi_vm_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_vm_events)) + ec = -KVM_EINVAL; + else if (!is_event_allowed(kvmi, req->event_id)) + ec = -KVM_EPERM; + else + ec = kvmi_cmd_vm_control_events(kvmi, req->event_id, + req->enable == 1); + + return kvmi_msg_vm_reply(kvmi, msg, ec, NULL, 0); +} + /* * These commands are executed by the receiving thread/worker. */ static int(*const msg_vm[])(struct kvm_introspection *, const struct kvmi_msg_hdr *, const void *) = { - [KVMI_GET_VERSION] = handle_get_version, - [KVMI_VM_CHECK_COMMAND] = handle_check_command, - [KVMI_VM_CHECK_EVENT] = handle_check_event, - [KVMI_VM_GET_INFO] = handle_get_info, + [KVMI_GET_VERSION] = handle_get_version, + [KVMI_VM_CHECK_COMMAND] = handle_check_command, + [KVMI_VM_CHECK_EVENT] = handle_check_event, + [KVMI_VM_CONTROL_EVENTS] = handle_vm_control_events, + [KVMI_VM_GET_INFO] = handle_get_info, }; static bool is_vm_command(u16 id) _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
