This is used by the introspection tool to check the hardware support
for the single step feature.
Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
---
Documentation/virt/kvm/kvmi.rst | 13 ++++++++++++-
arch/x86/include/uapi/asm/kvmi.h | 5 +++++
arch/x86/kvm/kvmi.c | 5 +++++
include/uapi/linux/kvmi.h | 1 +
tools/testing/selftests/kvm/x86_64/kvmi_test.c | 5 +++++
virt/kvm/introspection/kvmi_int.h | 1 +
virt/kvm/introspection/kvmi_msg.c | 2 ++
7 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst
index b2e2a9edda77..47387f297029 100644
--- a/Documentation/virt/kvm/kvmi.rst
+++ b/Documentation/virt/kvm/kvmi.rst
@@ -254,9 +254,20 @@ The vCPU commands start with::
struct kvmi_get_version_reply {
__u32 version;
__u32 padding;
+ struct kvmi_features features;
};
-Returns the introspection API version.
+For x86
+
+::
+
+ struct kvmi_features {
+ __u8 singlestep;
+ __u8 padding[7];
+ };
+
+Returns the introspection API version and some of the features supported
+by the hardware.
This command is always allowed and successful.
diff --git a/arch/x86/include/uapi/asm/kvmi.h b/arch/x86/include/uapi/asm/kvmi.h
index 1bb13da61dbf..32af803f1d70 100644
--- a/arch/x86/include/uapi/asm/kvmi.h
+++ b/arch/x86/include/uapi/asm/kvmi.h
@@ -145,4 +145,9 @@ struct kvmi_event_msr_reply {
__u64 new_val;
};
+struct kvmi_features {
+ __u8 singlestep;
+ __u8 padding[7];
+};
+
#endif /* _UAPI_ASM_X86_KVMI_H */
diff --git a/arch/x86/kvm/kvmi.c b/arch/x86/kvm/kvmi.c
index 8fbf1720749b..672a113b3bf4 100644
--- a/arch/x86/kvm/kvmi.c
+++ b/arch/x86/kvm/kvmi.c
@@ -1350,3 +1350,8 @@ static void kvmi_track_flush_slot(struct kvm *kvm, struct kvm_memory_slot *slot,
kvmi_put(kvm);
}
+
+void kvmi_arch_features(struct kvmi_features *feat)
+{
+ feat->singlestep = !!kvm_x86_ops.control_singlestep;
+}
diff --git a/include/uapi/linux/kvmi.h b/include/uapi/linux/kvmi.h
index dc7ba12498b7..a84affbafa67 100644
--- a/include/uapi/linux/kvmi.h
+++ b/include/uapi/linux/kvmi.h
@@ -101,6 +101,7 @@ struct kvmi_error_code {
struct kvmi_get_version_reply {
__u32 version;
__u32 padding;
+ struct kvmi_features features;
};
struct kvmi_vm_check_command {
diff --git a/tools/testing/selftests/kvm/x86_64/kvmi_test.c b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
index 21b3f7a459c8..eabe7dae149e 100644
--- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
@@ -56,6 +56,8 @@ struct vcpu_worker_data {
bool restart_on_shutdown;
};
+static struct kvmi_features features;
+
typedef void (*fct_pf_event)(struct kvm_vm *vm, struct kvmi_msg_hdr *hdr,
struct pf_ev *ev,
struct vcpu_reply *rpl);
@@ -437,7 +439,10 @@ static void test_cmd_get_version(void)
"Unexpected KVMI version %d, expecting %d\n",
rpl.version, KVMI_VERSION);
+ features = rpl.features;
+
pr_info("KVMI version: %u\n", rpl.version);
+ pr_info("\tsinglestep: %u\n", features.singlestep);
}
static void cmd_vm_check_command(__u16 id, __u16 padding, int expected_err)
diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h
index 9f2341fe21d5..68b8d60a7fac 100644
--- a/virt/kvm/introspection/kvmi_int.h
+++ b/virt/kvm/introspection/kvmi_int.h
@@ -138,5 +138,6 @@ void kvmi_arch_update_page_tracking(struct kvm *kvm,
struct kvmi_mem_access *m);
void kvmi_arch_hook(struct kvm *kvm);
void kvmi_arch_unhook(struct kvm *kvm);
+void kvmi_arch_features(struct kvmi_features *feat);
#endif
diff --git a/virt/kvm/introspection/kvmi_msg.c b/virt/kvm/introspection/kvmi_msg.c
index 0a0d10b43f2d..e754cee48912 100644
--- a/virt/kvm/introspection/kvmi_msg.c
+++ b/virt/kvm/introspection/kvmi_msg.c
@@ -148,6 +148,8 @@ static int handle_get_version(struct kvm_introspection *kvmi,
memset(&rpl, 0, sizeof(rpl));
rpl.version = kvmi_version();
+ kvmi_arch_features(&rpl.features);
+
return kvmi_msg_vm_reply(kvmi, msg, 0, &rpl, sizeof(rpl));
}
