[PATCH v12 72/77] KVM: introspection: extend KVMI_GET_VERSION with struct kvmi_features
From: Adalbert Lazăr <hidden>
Date: 2021-10-06 17:40:48
Also in:
kvm
Subsystem:
documentation, kernel selftest framework, kernel virtual machine (kvm), kernel virtual machine for x86 (kvm/x86), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Jonathan Corbet, Shuah Khan, Paolo Bonzini, Sean Christopherson, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
This is used by the introspection tool to check the hardware support for the single step feature. Signed-off-by: Adalbert Lazăr <redacted> --- Documentation/virt/kvm/kvmi.rst | 15 +++++++++++++-- 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 | 6 ++++++ virt/kvm/introspection/kvmi_int.h | 1 + virt/kvm/introspection/kvmi_msg.c | 2 ++ 7 files changed, 33 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst
index b12affb0d64f..54cb3fbe184e 100644
--- a/Documentation/virt/kvm/kvmi.rst
+++ b/Documentation/virt/kvm/kvmi.rst@@ -243,10 +243,21 @@ The vCPU commands start with:: struct kvmi_get_version_reply { __u32 version; __u32 max_msg_size; + struct kvmi_features features; }; -Returns the introspection API version and the largest accepted message -size (useful for variable length messages). +For x86 + +:: + + struct kvmi_features { + __u8 singlestep; + __u8 padding[7]; + }; + +Returns the introspection API version, the largest accepted message size +(useful for variable length messages) and some of the hardware supported +features. 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 6ef144ddb4bb..c5a2cb1b54f1 100644
--- a/arch/x86/include/uapi/asm/kvmi.h
+++ b/arch/x86/include/uapi/asm/kvmi.h@@ -159,4 +159,9 @@ struct kvmi_vcpu_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 6432c40817d2..eee874890e29 100644
--- a/arch/x86/kvm/kvmi.c
+++ b/arch/x86/kvm/kvmi.c@@ -1084,3 +1084,8 @@ 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 bb6265e4539a..b594463795c6 100644
--- a/include/uapi/linux/kvmi.h
+++ b/include/uapi/linux/kvmi.h@@ -102,6 +102,7 @@ struct kvmi_error_code { struct kvmi_get_version_reply { __u32 version; __u32 max_msg_size; + 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 9cf099b38bdf..f7735e3ea9e8 100644
--- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c@@ -59,6 +59,8 @@ 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);
@@ -443,6 +445,10 @@ static void test_cmd_get_version(void) pr_debug("KVMI version: %u\n", rpl.version); pr_debug("Max message size: %u\n", rpl.max_msg_size); + + features = rpl.features; + + pr_debug("singlestep support: %u\n", features.singlestep); } static void cmd_vm_check_command(__u16 id, int expected_err)
diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h
index bf6545e66425..a51e7e4ed511 100644
--- a/virt/kvm/introspection/kvmi_int.h
+++ b/virt/kvm/introspection/kvmi_int.h@@ -121,5 +121,6 @@ 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 745d10981b6f..e2aef76bfd16 100644
--- a/virt/kvm/introspection/kvmi_msg.c
+++ b/virt/kvm/introspection/kvmi_msg.c@@ -134,6 +134,8 @@ static int handle_get_version(struct kvm_introspection *kvmi, rpl.version = kvmi_version(); rpl.max_msg_size = KVMI_MAX_MSG_SIZE; + kvmi_arch_features(&rpl.features); + return kvmi_msg_vm_reply(kvmi, msg, 0, &rpl, sizeof(rpl)); }
_______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization