This helps the introspection tool with the GVA to GPA translations
without the need to read or monitor the guest page tables.
Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
---
Documentation/virt/kvm/kvmi.rst | 32 +++++++++++++++++++
arch/x86/kvm/kvmi.c | 5 +++
include/uapi/linux/kvmi.h | 9 ++++++
.../testing/selftests/kvm/x86_64/kvmi_test.c | 30 +++++++++++++++++
virt/kvm/introspection/kvmi_int.h | 1 +
virt/kvm/introspection/kvmi_msg.c | 15 +++++++++
6 files changed, 92 insertions(+)
diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst
index 3c481c1b2186..62138fa4b65c 100644
--- a/Documentation/virt/kvm/kvmi.rst
+++ b/Documentation/virt/kvm/kvmi.rst
@@ -1086,6 +1086,38 @@ to the introspection tool.
* -KVM_EINVAL - the padding is not zero
* -KVM_EAGAIN - the selected vCPU can't be introspected yet
+25. KVMI_VCPU_TRANSLATE_GVA
+---------------------------
+
+:Architecture: x86
+:Versions: >= 1
+:Parameters:
+
+::
+
+ struct kvmi_vcpu_hdr;
+ struct kvmi_vcpu_translate_gva {
+ __u64 gva;
+ };
+
+:Returns:
+
+::
+
+ struct kvmi_error_code;
+ struct kvmi_vcpu_translate_gva_reply {
+ __u64 gpa;
+ };
+
+Translates a guest virtual address to a guest physical address or ~0 if
+the address cannot be translated.
+
+:Errors:
+
+* -KVM_EINVAL - the selected vCPU is invalid
+* -KVM_EINVAL - the padding is not zero
+* -KVM_EAGAIN - the selected vCPU can't be introspected yet
+
Events
======
diff --git a/arch/x86/kvm/kvmi.c b/arch/x86/kvm/kvmi.c
index 18713004152d..8051d06064ab 100644
--- a/arch/x86/kvm/kvmi.c
+++ b/arch/x86/kvm/kvmi.c
@@ -1373,3 +1373,8 @@ bool kvmi_arch_stop_singlestep(struct kvm_vcpu *vcpu)
kvm_x86_ops.control_singlestep(vcpu, false);
return true;
}
+
+gpa_t kvmi_arch_cmd_translate_gva(struct kvm_vcpu *vcpu, gva_t gva)
+{
+ return kvm_mmu_gva_to_gpa_system(vcpu, gva, 0, NULL);
+}
diff --git a/include/uapi/linux/kvmi.h b/include/uapi/linux/kvmi.h
index 040049abd450..3c15c17d28e3 100644
--- a/include/uapi/linux/kvmi.h
+++ b/include/uapi/linux/kvmi.h
@@ -48,6 +48,7 @@ enum {
KVMI_VM_SET_PAGE_ACCESS = 23,
KVMI_VCPU_CONTROL_SINGLESTEP = 24,
+ KVMI_VCPU_TRANSLATE_GVA = 25,
KVMI_NUM_MESSAGES
};
@@ -242,4 +243,12 @@ struct kvmi_event_singlestep {
__u8 padding[7];
};
+struct kvmi_vcpu_translate_gva {
+ __u64 gva;
+};
+
+struct kvmi_vcpu_translate_gva_reply {
+ __u64 gpa;
+};
+
#endif /* _UAPI__LINUX_KVMI_H */
diff --git a/tools/testing/selftests/kvm/x86_64/kvmi_test.c b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
index 967ea568d93c..e968b1a6f969 100644
--- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
@@ -2040,6 +2040,35 @@ static void test_cmd_vcpu_control_singlestep(struct kvm_vm *vm)
test_unsupported_singlestep(vm);
}
+static void cmd_translate_gva(struct kvm_vm *vm, vm_vaddr_t gva,
+ vm_paddr_t expected_gpa)
+{
+ struct {
+ struct kvmi_msg_hdr hdr;
+ struct kvmi_vcpu_hdr vcpu_hdr;
+ struct kvmi_vcpu_translate_gva cmd;
+ } req = { 0 };
+ struct kvmi_vcpu_translate_gva_reply rpl;
+
+ req.cmd.gva = gva;
+
+ test_vcpu0_command(vm, KVMI_VCPU_TRANSLATE_GVA, &req.hdr, sizeof(req),
+ &rpl, sizeof(rpl));
+ TEST_ASSERT(rpl.gpa == expected_gpa,
+ "Translation failed for gva 0x%lx -> gpa 0x%llx instead of 0x%lx\n",
+ gva, rpl.gpa, expected_gpa);
+}
+
+static void test_cmd_translate_gva(struct kvm_vm *vm)
+{
+ cmd_translate_gva(vm, test_gva, test_gpa);
+ pr_info("Tested gva 0x%lx to gpa 0x%lx\n", test_gva, test_gpa);
+
+ cmd_translate_gva(vm, -1, ~0);
+ pr_info("Tested gva 0x%lx to gpa 0x%lx\n",
+ (vm_vaddr_t)-1, (vm_paddr_t)-1);
+}
+
static void test_introspection(struct kvm_vm *vm)
{
srandom(time(0));
@@ -2075,6 +2104,7 @@ static void test_introspection(struct kvm_vm *vm)
test_cmd_vm_set_page_access(vm);
test_event_pf(vm);
test_cmd_vcpu_control_singlestep(vm);
+ test_cmd_translate_gva(vm);
unhook_introspection(vm);
}
diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h
index e5fca3502bab..cb8453f0fb87 100644
--- a/virt/kvm/introspection/kvmi_int.h
+++ b/virt/kvm/introspection/kvmi_int.h
@@ -141,5 +141,6 @@ void kvmi_arch_unhook(struct kvm *kvm);
void kvmi_arch_features(struct kvmi_features *feat);
bool kvmi_arch_start_singlestep(struct kvm_vcpu *vcpu);
bool kvmi_arch_stop_singlestep(struct kvm_vcpu *vcpu);
+gpa_t kvmi_arch_cmd_translate_gva(struct kvm_vcpu *vcpu, gva_t gva);
#endif
diff --git a/virt/kvm/introspection/kvmi_msg.c b/virt/kvm/introspection/kvmi_msg.c
index 645debc47f13..d8874bd7a8b7 100644
--- a/virt/kvm/introspection/kvmi_msg.c
+++ b/virt/kvm/introspection/kvmi_msg.c
@@ -647,6 +647,20 @@ static int handle_vcpu_control_singlestep(const struct kvmi_vcpu_msg_job *job,
return kvmi_msg_vcpu_reply(job, msg, ec, NULL, 0);
}
+static int handle_vcpu_translate_gva(const struct kvmi_vcpu_msg_job *job,
+ const struct kvmi_msg_hdr *msg,
+ const void *_req)
+{
+ const struct kvmi_vcpu_translate_gva *req = _req;
+ struct kvmi_vcpu_translate_gva_reply rpl;
+
+ memset(&rpl, 0, sizeof(rpl));
+
+ rpl.gpa = kvmi_arch_cmd_translate_gva(job->vcpu, req->gva);
+
+ return kvmi_msg_vcpu_reply(job, msg, 0, &rpl, sizeof(rpl));
+}
+
/*
* These functions are executed from the vCPU thread. The receiving thread
* passes the messages using a newly allocated 'struct kvmi_vcpu_msg_job'
@@ -669,6 +683,7 @@ static int(*const msg_vcpu[])(const struct kvmi_vcpu_msg_job *,
[KVMI_VCPU_INJECT_EXCEPTION] = handle_vcpu_inject_exception,
[KVMI_VCPU_SET_REGISTERS] = handle_vcpu_set_registers,
[KVMI_VCPU_SET_XSAVE] = handle_vcpu_set_xsave,
+ [KVMI_VCPU_TRANSLATE_GVA] = handle_vcpu_translate_gva,
};
static bool is_vcpu_command(u16 id)
