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/virtual/kvm/kvmi.rst | 43 ++++++++++++++++
arch/x86/include/uapi/asm/kvmi.h | 15 ++++++
arch/x86/kvm/kvmi.c | 78 ++++++++++++++++++++++++++++++
virt/kvm/kvmi_int.h | 5 ++
virt/kvm/kvmi_msg.c | 17 +++++++
5 files changed, 158 insertions(+)
diff --git a/Documentation/virtual/kvm/kvmi.rst b/Documentation/virtual/kvm/kvmi.rst
index 558d3eb6007f..edf81e03ca3c 100644
--- a/Documentation/virtual/kvm/kvmi.rst
+++ b/Documentation/virtual/kvm/kvmi.rst
@@ -862,6 +862,49 @@ The introspection tool should use *KVMI_CONTROL_VM_EVENTS* to enable the
* -KVM_EBUSY - the selected vCPU has too many queued *KVMI_EVENT_PAUSE_VCPU* events
* -KVM_EPERM - the *KVMI_EVENT_PAUSE_VCPU* event is disallowed (see *KVMI_CONTROL_EVENTS*)
and the introspection tool expects a reply.
+
+17. KVMI_GET_REGISTERS
+----------------------
+
+:Architectures: x86
+:Versions: >= 1
+:Parameters:
+
+::
+
+ struct kvmi_vcpu_hdr;
+ struct kvmi_get_registers {
+ __u16 nmsrs;
+ __u16 padding1;
+ __u32 padding2;
+ __u32 msrs_idx[0];
+ };
+
+:Returns:
+
+::
+
+ struct kvmi_error_code;
+ struct kvmi_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 MSR-s 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 551f9ed1ed9c..98fb27e1273c 100644
--- a/arch/x86/include/uapi/asm/kvmi.h
+++ b/arch/x86/include/uapi/asm/kvmi.h
@@ -26,4 +26,19 @@ struct kvmi_event_arch {
} msrs;
};
+struct kvmi_get_registers {
+ __u16 nmsrs;
+ __u16 padding1;
+ __u32 padding2;
+ __u32 msrs_idx[0];
+};
+
+struct kvmi_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 fa290fbf1f75..a78771b21d2f 100644
--- a/arch/x86/kvm/kvmi.c
+++ b/arch/x86/kvm/kvmi.c
@@ -7,6 +7,25 @@
#include "x86.h"
#include "../../../virt/kvm/kvmi_int.h"
+static void *alloc_get_registers_reply(const struct kvmi_msg_hdr *msg,
+ const struct kvmi_get_registers *req,
+ size_t *rpl_size)
+{
+ struct kvmi_get_registers_reply *rpl;
+ u16 k, n = req->nmsrs;
+
+ *rpl_size = sizeof(*rpl) + sizeof(rpl->msrs.entries[0]) * 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;
+}
+
/*
* TODO: this can be done from userspace.
* - all these registers are sent with struct kvmi_event_arch
@@ -38,6 +57,65 @@ static unsigned int kvmi_vcpu_mode(const struct kvm_vcpu *vcpu,
return mode;
}
+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;
+
+ 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_get_msr(vcpu, &m);
+
+ if (err)
+ return -KVM_EINVAL;
+
+ msr->data = m.data;
+ }
+
+ return 0;
+}
+
+int kvmi_arch_cmd_get_registers(struct kvm_vcpu *vcpu,
+ const struct kvmi_msg_hdr *msg,
+ const struct kvmi_get_registers *req,
+ struct kvmi_get_registers_reply **dest,
+ size_t *dest_size)
+{
+ struct kvmi_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)
+ + sizeof(*req) + req->nmsrs * sizeof(req->msrs_idx[0]))
+ 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;
+
+}
+
static void kvmi_get_msrs(struct kvm_vcpu *vcpu, struct kvmi_event_arch *event)
{
struct msr_data msr;
diff --git a/virt/kvm/kvmi_int.h b/virt/kvm/kvmi_int.h
index cb3b0ce87bc1..b547809d13ae 100644
--- a/virt/kvm/kvmi_int.h
+++ b/virt/kvm/kvmi_int.h
@@ -200,6 +200,11 @@ void kvmi_handle_common_event_actions(struct kvm_vcpu *vcpu, u32 action,
void kvmi_arch_update_page_tracking(struct kvm *kvm,
struct kvm_memory_slot *slot,
struct kvmi_mem_access *m);
+int kvmi_arch_cmd_get_registers(struct kvm_vcpu *vcpu,
+ const struct kvmi_msg_hdr *msg,
+ const struct kvmi_get_registers *req,
+ struct kvmi_get_registers_reply **dest,
+ size_t *dest_size);
int kvmi_arch_cmd_get_page_access(struct kvmi *ikvm,
const struct kvmi_msg_hdr *msg,
const struct kvmi_get_page_access *req,
diff --git a/virt/kvm/kvmi_msg.c b/virt/kvm/kvmi_msg.c
index a4446eed354d..9ae0622ff09e 100644
--- a/virt/kvm/kvmi_msg.c
+++ b/virt/kvm/kvmi_msg.c
@@ -32,6 +32,7 @@ static const char *const msg_IDs[] = {
[KVMI_GET_GUEST_INFO] = "KVMI_GET_GUEST_INFO",
[KVMI_GET_PAGE_ACCESS] = "KVMI_GET_PAGE_ACCESS",
[KVMI_GET_PAGE_WRITE_BITMAP] = "KVMI_GET_PAGE_WRITE_BITMAP",
+ [KVMI_GET_REGISTERS] = "KVMI_GET_REGISTERS",
[KVMI_GET_VCPU_INFO] = "KVMI_GET_VCPU_INFO",
[KVMI_GET_VERSION] = "KVMI_GET_VERSION",
[KVMI_PAUSE_VCPU] = "KVMI_PAUSE_VCPU",
@@ -589,6 +590,21 @@ static int handle_get_vcpu_info(struct kvm_vcpu *vcpu,
return reply_cb(vcpu, msg, 0, &rpl, sizeof(rpl));
}
+static int handle_get_registers(struct kvm_vcpu *vcpu,
+ const struct kvmi_msg_hdr *msg,
+ const void *req, vcpu_reply_fct reply_cb)
+{
+ struct kvmi_get_registers_reply *rpl = NULL;
+ size_t rpl_size = 0;
+ int err, ec;
+
+ ec = kvmi_arch_cmd_get_registers(vcpu, msg, req, &rpl, &rpl_size);
+
+ err = reply_cb(vcpu, msg, ec, rpl, rpl_size);
+ kvmi_msg_free(rpl);
+ return err;
+}
+
static int handle_control_events(struct kvm_vcpu *vcpu,
const struct kvmi_msg_hdr *msg,
const void *_req,
@@ -622,6 +638,7 @@ static int(*const msg_vcpu[])(struct kvm_vcpu *,
vcpu_reply_fct) = {
[KVMI_CONTROL_EVENTS] = handle_control_events,
[KVMI_EVENT_REPLY] = handle_event_reply,
+ [KVMI_GET_REGISTERS] = handle_get_registers,
[KVMI_GET_VCPU_INFO] = handle_get_vcpu_info,
};
