From: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx>
This command is used to get kvm_regs and kvm_sregs structures,
plus the list of struct kvm_msrs.
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 | 42 +++++++++++
arch/x86/include/uapi/asm/kvmi.h | 15 ++++
arch/x86/kvm/kvmi.c | 70 +++++++++++++++++++
include/uapi/linux/kvmi.h | 1 +
.../testing/selftests/kvm/x86_64/kvmi_test.c | 26 +++++++
virt/kvm/introspection/kvmi_int.h | 6 ++
virt/kvm/introspection/kvmi_msg.c | 18 +++++
7 files changed, 178 insertions(+)
diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst
index c48abc8f5c97..5c366bcd3112 100644
--- a/Documentation/virt/kvm/kvmi.rst
+++ b/Documentation/virt/kvm/kvmi.rst
@@ -547,6 +547,48 @@ by the *KVMI_VM_CONTROL_EVENTS* command.
* -KVM_EPERM - the access is restricted by the host
* -KVM_EOPNOTSUPP - one the events can't be intercepted in the current setup
+11. KVMI_VCPU_GET_REGISTERS
+---------------------------
+
+:Architectures: x86
+:Versions: >= 1
+:Parameters:
+
+::
+
+ struct kvmi_vcpu_hdr;
+ struct kvmi_vcpu_get_registers {
+ __u16 nmsrs;
+ __u16 padding1;
+ __u32 padding2;
+ __u32 msrs_idx[0];
+ };
+
+:Returns:
+
+::
+
+ struct kvmi_error_code;
+ struct kvmi_vcpu_get_registers_reply {
+ __u32 mode;
+ __u32 padding;
+ struct kvm_regs regs;
+ struct kvm_sregs sregs;
+ struct kvm_msrs msrs;
+ };
+
+For the given vCPU and the ``nmsrs`` sized array of MSRs registers,
+returns the current vCPU mode (in bytes: 2, 4 or 8), the general purpose
+registers, the special registers and the requested set of MSRs.
+
+:Errors:
+
+* -KVM_EINVAL - the selected vCPU is invalid
+* -KVM_EINVAL - one of the indicated MSRs is invalid
+* -KVM_EINVAL - padding is not zero
+* -KVM_EAGAIN - the selected vCPU can't be introspected yet
+* -KVM_ENOMEM - not enough memory to allocate the reply
+
Events
======
diff --git a/arch/x86/include/uapi/asm/kvmi.h b/arch/x86/include/uapi/asm/kvmi.h
index 89adf84cefe4..f14674c3c109 100644
--- a/arch/x86/include/uapi/asm/kvmi.h
+++ b/arch/x86/include/uapi/asm/kvmi.h
@@ -30,4 +30,19 @@ struct kvmi_vcpu_get_info_reply {
__u64 tsc_speed;
};
+struct kvmi_vcpu_get_registers {
+ __u16 nmsrs;
+ __u16 padding1;
+ __u32 padding2;
+ __u32 msrs_idx[0];
+};
+
+struct kvmi_vcpu_get_registers_reply {
+ __u32 mode;
+ __u32 padding;
+ struct kvm_regs regs;
+ struct kvm_sregs sregs;
+ struct kvm_msrs msrs;
+};
+
#endif /* _UAPI_ASM_X86_KVMI_H */
diff --git a/arch/x86/kvm/kvmi.c b/arch/x86/kvm/kvmi.c
index 842d6abebb41..67cf2d19ba0f 100644
--- a/arch/x86/kvm/kvmi.c
+++ b/arch/x86/kvm/kvmi.c
@@ -70,3 +70,73 @@ int kvmi_arch_cmd_vcpu_get_info(struct kvm_vcpu *vcpu,
return 0;
}
+
+static void *
+alloc_get_registers_reply(const struct kvmi_msg_hdr *msg,
+ const struct kvmi_vcpu_get_registers *req,
+ size_t *rpl_size)
+{
+ struct kvmi_vcpu_get_registers_reply *rpl;
+ u16 k, n = req->nmsrs;
+
+ *rpl_size = struct_size(rpl, msrs.entries, n);
+ rpl = kvmi_msg_alloc_check(*rpl_size);
+ if (rpl) {
+ rpl->msrs.nmsrs = n;
+
+ for (k = 0; k < n; k++)
+ rpl->msrs.entries[k].index = req->msrs_idx[k];
+ }
+
+ return rpl;
+}
+
+static int kvmi_get_registers(struct kvm_vcpu *vcpu, u32 *mode,
+ struct kvm_regs *regs,
+ struct kvm_sregs *sregs,
+ struct kvm_msrs *msrs)
+{
+ struct kvm_msr_entry *msr = msrs->entries;
+ struct kvm_msr_entry *end = msrs->entries + msrs->nmsrs;
+ int err = 0;
+
+ kvm_arch_vcpu_get_regs(vcpu, regs);
+ kvm_arch_vcpu_get_sregs(vcpu, sregs);
+ *mode = kvmi_vcpu_mode(vcpu, sregs);
+
+ for (; msr < end && !err; msr++)
+ err = __kvm_get_msr(vcpu, msr->index, &msr->data, true);
+
+ return err ? -KVM_EINVAL : 0;
+}
+
+int kvmi_arch_cmd_vcpu_get_registers(struct kvm_vcpu *vcpu,
+ const struct kvmi_msg_hdr *msg,
+ const struct kvmi_vcpu_get_registers *req,
+ struct kvmi_vcpu_get_registers_reply **dest,
+ size_t *dest_size)
+{
+ struct kvmi_vcpu_get_registers_reply *rpl;
+ size_t rpl_size = 0;
+ int err;
+
+ if (req->padding1 || req->padding2)
+ return -KVM_EINVAL;
+
+ if (msg->size < sizeof(struct kvmi_vcpu_hdr)
+ + struct_size(req, msrs_idx, req->nmsrs))
+ return -KVM_EINVAL;
+
+ rpl = alloc_get_registers_reply(msg, req, &rpl_size);
+ if (!rpl)
+ return -KVM_ENOMEM;
+
+ err = kvmi_get_registers(vcpu, &rpl->mode, &rpl->regs,
+ &rpl->sregs, &rpl->msrs);
+
+ *dest = rpl;
+ *dest_size = rpl_size;
+
+ return err;
+
+}
diff --git a/include/uapi/linux/kvmi.h b/include/uapi/linux/kvmi.h
index 745503fb7378..bdb5f977c240 100644
--- a/include/uapi/linux/kvmi.h
+++ b/include/uapi/linux/kvmi.h
@@ -29,6 +29,7 @@ enum {
KVMI_VCPU_GET_INFO = 9,
KVMI_VCPU_PAUSE = 10,
KVMI_VCPU_CONTROL_EVENTS = 11,
+ KVMI_VCPU_GET_REGISTERS = 12,
KVMI_NUM_MESSAGES
};
diff --git a/tools/testing/selftests/kvm/x86_64/kvmi_test.c b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
index 830b64cae20b..5d76d49bc277 100644
--- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
@@ -803,6 +803,31 @@ static void test_cmd_vcpu_control_events(struct kvm_vm *vm)
test_invalid_vcpu_event(vm, invalid_id);
}
+static void get_vcpu_registers(struct kvm_vm *vm,
+ struct kvm_regs *regs)
+{
+ struct {
+ struct kvmi_msg_hdr hdr;
+ struct kvmi_vcpu_hdr vcpu_hdr;
+ struct kvmi_vcpu_get_registers cmd;
+ } req = {};
+ struct kvmi_vcpu_get_registers_reply rpl;
+
+ test_vcpu0_command(vm, KVMI_VCPU_GET_REGISTERS, &req.hdr, sizeof(req),
+ &rpl, sizeof(rpl));
+
+ memcpy(regs, &rpl.regs, sizeof(*regs));
+}
+
+static void test_cmd_vcpu_get_registers(struct kvm_vm *vm)
+{
+ struct kvm_regs regs = {};
+
+ get_vcpu_registers(vm, ®s);
+
+ DEBUG("get_registers rip 0x%llx\n", regs.rip);
+}
+
static void test_introspection(struct kvm_vm *vm)
{
setup_socket();
@@ -819,6 +844,7 @@ static void test_introspection(struct kvm_vm *vm)
test_cmd_get_vcpu_info(vm);
test_pause(vm);
test_cmd_vcpu_control_events(vm);
+ test_cmd_vcpu_get_registers(vm);
unhook_introspection(vm);
}
diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h
index fe59696b0826..5c9ba4b1107e 100644
--- a/virt/kvm/introspection/kvmi_int.h
+++ b/virt/kvm/introspection/kvmi_int.h
@@ -38,6 +38,7 @@
| BIT(KVMI_VCPU_GET_INFO) \
| BIT(KVMI_VCPU_PAUSE) \
| BIT(KVMI_VCPU_CONTROL_EVENTS) \
+ | BIT(KVMI_VCPU_GET_REGISTERS) \
)
#define KVMI(kvm) ((struct kvm_introspection *)((kvm)->kvmi))
@@ -82,5 +83,10 @@ int kvmi_cmd_vcpu_pause(struct kvm_vcpu *vcpu, bool wait);
int kvmi_arch_cmd_vcpu_get_info(struct kvm_vcpu *vcpu,
struct kvmi_vcpu_get_info_reply *rpl);
void kvmi_arch_setup_event(struct kvm_vcpu *vcpu, struct kvmi_event *ev);
+int kvmi_arch_cmd_vcpu_get_registers(struct kvm_vcpu *vcpu,
+ const struct kvmi_msg_hdr *msg,
+ const struct kvmi_vcpu_get_registers *req,
+ struct kvmi_vcpu_get_registers_reply **dest,
+ size_t *dest_size);
#endif
diff --git a/virt/kvm/introspection/kvmi_msg.c b/virt/kvm/introspection/kvmi_msg.c
index 1995a63f4e99..4a7c831183bb 100644
--- a/virt/kvm/introspection/kvmi_msg.c
+++ b/virt/kvm/introspection/kvmi_msg.c
@@ -27,6 +27,7 @@ static const char *const msg_IDs[] = {
[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_GET_REGISTERS] = "KVMI_VCPU_GET_REGISTERS",
[KVMI_VCPU_PAUSE] = "KVMI_VCPU_PAUSE",
};
@@ -434,6 +435,22 @@ static int handle_vcpu_control_events(const struct kvmi_vcpu_cmd_job *job,
return kvmi_msg_vcpu_reply(job, msg, ec, NULL, 0);
}
+static int handle_get_registers(const struct kvmi_vcpu_cmd_job *job,
+ const struct kvmi_msg_hdr *msg,
+ const void *req)
+{
+ struct kvmi_vcpu_get_registers_reply *rpl = NULL;
+ size_t rpl_size = 0;
+ int err, ec;
+
+ ec = kvmi_arch_cmd_vcpu_get_registers(job->vcpu, msg, req,
+ &rpl, &rpl_size);
+
+ err = kvmi_msg_vcpu_reply(job, msg, ec, rpl, rpl_size);
+ kvmi_msg_free(rpl);
+ return err;
+}
+
/*
* These commands are executed on the vCPU thread. The receiving thread
* passes the messages using a newly allocated 'struct kvmi_vcpu_cmd_job'
@@ -445,6 +462,7 @@ static int(*const msg_vcpu[])(const struct kvmi_vcpu_cmd_job *,
[KVMI_EVENT_REPLY] = handle_event_reply,
[KVMI_VCPU_CONTROL_EVENTS] = handle_vcpu_control_events,
[KVMI_VCPU_GET_INFO] = handle_get_vcpu_info,
+ [KVMI_VCPU_GET_REGISTERS] = handle_get_registers,
};
static void kvmi_job_vcpu_cmd(struct kvm_vcpu *vcpu, void *ctx)
