From: Mihai Donțu <[email protected]> This command is used to get kvm_regs and kvm_sregs structures, plus the list of struct kvm_msrs.
Signed-off-by: Mihai Donțu <[email protected]> Co-developed-by: Adalbert Lazăr <[email protected]> Signed-off-by: Adalbert Lazăr <[email protected]> --- Documentation/virt/kvm/kvmi.rst | 42 +++++++++ arch/x86/include/uapi/asm/kvmi.h | 15 +++ arch/x86/kvm/kvmi.c | 91 +++++++++++++++++++ include/uapi/linux/kvmi.h | 1 + .../testing/selftests/kvm/x86_64/kvmi_test.c | 26 ++++++ virt/kvm/introspection/kvmi.c | 7 ++ virt/kvm/introspection/kvmi_int.h | 8 ++ virt/kvm/introspection/kvmi_msg.c | 21 +++++ 8 files changed, 211 insertions(+) diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst index b0eb2649b10c..0000099e8038 100644 --- a/Documentation/virt/kvm/kvmi.rst +++ b/Documentation/virt/kvm/kvmi.rst @@ -566,6 +566,48 @@ the *KVMI_VM_CONTROL_EVENTS* command. * -KVM_EPERM - the access is disallowed (use *KVMI_VM_CHECK_EVENT* first) * -KVM_EAGAIN - the selected vCPU can't be introspected yet +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 - the padding is not zero +* -KVM_EAGAIN - the selected vCPU can't be introspected yet +* -KVM_ENOMEM - there is 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 21ff48cfdb89..1ba264c10cff 100644 --- a/arch/x86/kvm/kvmi.c +++ b/arch/x86/kvm/kvmi.c @@ -98,3 +98,94 @@ int kvmi_arch_cmd_vcpu_get_info(struct kvm_vcpu *vcpu, return 0; } + +int kvmi_arch_check_get_registers_req(const struct kvmi_msg_hdr *msg, + const struct kvmi_vcpu_get_registers *req) +{ + size_t req_size; + + if (check_add_overflow(sizeof(struct kvmi_vcpu_hdr), + struct_size(req, msrs_idx, req->nmsrs), + &req_size)) + return -1; + + if (msg->size != req_size) + return -1; + + 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; msr++) { + struct msr_data m = { + .index = msr->index, + .host_initiated = true + }; + int err = kvm_x86_ops->get_msr(vcpu, &m); + + if (err) + break; + + msr->data = m.data; + } + + 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; + int err; + + if (req->padding1 || req->padding2) + 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 e361d6e6563d..c354c5e15be1 100644 --- a/include/uapi/linux/kvmi.h +++ b/include/uapi/linux/kvmi.h @@ -28,6 +28,7 @@ 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 94378066d69a..2fb191740cae 100644 --- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c +++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c @@ -807,6 +807,31 @@ 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) { srandom(time(0)); @@ -824,6 +849,7 @@ 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.c b/virt/kvm/introspection/kvmi.c index b6b3efd085c4..8d292a4be270 100644 --- a/virt/kvm/introspection/kvmi.c +++ b/virt/kvm/introspection/kvmi.c @@ -26,6 +26,13 @@ void *kvmi_msg_alloc(void) return kmem_cache_zalloc(msg_cache, GFP_KERNEL); } +void *kvmi_msg_alloc_check(size_t size) +{ + if (size > KVMI_MSG_SIZE_ALLOC) + return NULL; + return kvmi_msg_alloc(); +} + void kvmi_msg_free(void *addr) { if (addr) diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h index e94356516a05..3e471e3a755d 100644 --- a/virt/kvm/introspection/kvmi_int.h +++ b/virt/kvm/introspection/kvmi_int.h @@ -33,6 +33,7 @@ u32 kvmi_msg_send_vcpu_pause(struct kvm_vcpu *vcpu); /* kvmi.c */ void *kvmi_msg_alloc(void); +void *kvmi_msg_alloc_check(size_t size); void kvmi_msg_free(void *addr); int kvmi_add_job(struct kvm_vcpu *vcpu, void (*fct)(struct kvm_vcpu *vcpu, void *ctx), @@ -55,5 +56,12 @@ 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_check_get_registers_req(const struct kvmi_msg_hdr *msg, + const struct kvmi_vcpu_get_registers *req); +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 f819d0a942dc..e30e1ad5e443 100644 --- a/virt/kvm/introspection/kvmi_msg.c +++ b/virt/kvm/introspection/kvmi_msg.c @@ -30,6 +30,7 @@ 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", }; @@ -466,6 +467,25 @@ 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; + + if (kvmi_arch_check_get_registers_req(msg, req)) + return -EINVAL; + + 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 from the vCPU thread. The receiving thread * passes the messages using a newly allocated 'struct kvmi_vcpu_cmd_job' @@ -477,6 +497,7 @@ static int(*const msg_vcpu[])(const struct kvmi_vcpu_cmd_job *, [KVMI_EVENT] = 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 bool is_vcpu_command(u16 id) _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
