This can be used by the introspection tool to emulate SSE instructions.
Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
---
Documentation/virt/kvm/kvmi.rst | 29 +++++++++++++++++
arch/x86/include/uapi/asm/kvmi.h | 4 +++
arch/x86/kvm/kvmi.c | 23 ++++++++++++++
include/uapi/linux/kvmi.h | 1 +
.../testing/selftests/kvm/x86_64/kvmi_test.c | 31 +++++++++++++++----
virt/kvm/introspection/kvmi_int.h | 3 ++
virt/kvm/introspection/kvmi_msg.c | 17 ++++++++++
7 files changed, 102 insertions(+), 6 deletions(-)
diff --git a/Documentation/virt/kvm/kvmi.rst b/Documentation/virt/kvm/kvmi.rst
index 9bf8b08eb585..24605aaede9a 100644
--- a/Documentation/virt/kvm/kvmi.rst
+++ b/Documentation/virt/kvm/kvmi.rst
@@ -873,6 +873,35 @@ the buffer size from the message size (kvmi_msg_hdr.size).
* -KVM_EAGAIN - the selected vCPU can't be introspected yet
* -KVM_ENOMEM - there is not enough memory to allocate the reply
+20. KVMI_VCPU_SET_XSAVE
+-----------------------
+
+:Architecture: x86
+:Versions: >= 1
+:Parameters:
+
+::
+
+ struct kvmi_vcpu_hdr;
+ struct kvmi_vcpu_set_xsave {
+ __u32 region[0];
+ };
+
+:Returns:
+
+::
+
+ struct kvmi_error_code;
+
+Modifies the XSAVE area.
+
+:Errors:
+
+* -KVM_EINVAL - the buffer is larger than ``struct kvm_xsave``
+* -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/include/uapi/asm/kvmi.h b/arch/x86/include/uapi/asm/kvmi.h
index a165c259ba0e..71206206973c 100644
--- a/arch/x86/include/uapi/asm/kvmi.h
+++ b/arch/x86/include/uapi/asm/kvmi.h
@@ -103,4 +103,8 @@ struct kvmi_vcpu_get_xsave_reply {
__u32 region[0];
};
+struct kvmi_vcpu_set_xsave {
+ __u32 region[0];
+};
+
#endif /* _UAPI_ASM_X86_KVMI_H */
diff --git a/arch/x86/kvm/kvmi.c b/arch/x86/kvm/kvmi.c
index 7b7122784f0f..0776be48ada1 100644
--- a/arch/x86/kvm/kvmi.c
+++ b/arch/x86/kvm/kvmi.c
@@ -761,3 +761,26 @@ int kvmi_arch_cmd_vcpu_get_xsave(struct kvm_vcpu *vcpu,
return 0;
}
+
+int kvmi_arch_cmd_vcpu_set_xsave(struct kvm_vcpu *vcpu,
+ const struct kvmi_vcpu_set_xsave *req,
+ size_t req_size)
+{
+ struct kvm_xsave *area;
+ size_t dest_size = sizeof(*area);
+ int err;
+
+ if (req_size > dest_size)
+ return -KVM_EINVAL;
+
+ area = kzalloc(dest_size, GFP_KERNEL);
+ if (!area)
+ return -KVM_ENOMEM;
+
+ memcpy(area, req, min(req_size, dest_size));
+
+ err = kvm_vcpu_ioctl_x86_set_xsave(vcpu, area);
+ kfree(area);
+
+ return err ? -KVM_EINVAL : 0;
+}
diff --git a/include/uapi/linux/kvmi.h b/include/uapi/linux/kvmi.h
index 6b5662f54ba1..441586cec238 100644
--- a/include/uapi/linux/kvmi.h
+++ b/include/uapi/linux/kvmi.h
@@ -41,6 +41,7 @@ enum {
KVMI_VCPU_GET_XCR = 18,
KVMI_VCPU_GET_XSAVE = 19,
+ KVMI_VCPU_SET_XSAVE = 20,
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 657684ec6ff5..30741983a3ab 100644
--- a/tools/testing/selftests/kvm/x86_64/kvmi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvmi_test.c
@@ -1551,25 +1551,43 @@ static void test_cmd_vcpu_get_xcr(struct kvm_vm *vm)
cmd_vcpu_get_xcr(vm, xcr1, &value, no_padding, -KVM_EINVAL);
}
-static void cmd_vcpu_get_xsave(struct kvm_vm *vm)
+static void cmd_vcpu_get_xsave(struct kvm_vm *vm, struct kvm_xsave *rpl)
{
struct {
struct kvmi_msg_hdr hdr;
struct kvmi_vcpu_hdr vcpu_hdr;
} req = {};
- struct kvm_xsave rpl;
int r;
r = do_vcpu0_command(vm, KVMI_VCPU_GET_XSAVE, &req.hdr, sizeof(req),
- &rpl, sizeof(rpl));
+ rpl, sizeof(*rpl));
TEST_ASSERT(r == 0,
"KVMI_VCPU_GET_XSAVE failed with error %d (%s)\n",
-r, kvm_strerror(-r));
}
-static void test_cmd_vcpu_get_xsave(struct kvm_vm *vm)
+static void cmd_vcpu_set_xsave(struct kvm_vm *vm, struct kvm_xsave *rpl)
+{
+ struct {
+ struct kvmi_msg_hdr hdr;
+ struct kvmi_vcpu_hdr vcpu_hdr;
+ struct kvm_xsave xsave;
+ } req = {};
+ int r;
+
+ memcpy(&req.xsave, rpl, sizeof(*rpl));
+
+ r = do_vcpu0_command(vm, KVMI_VCPU_SET_XSAVE, &req.hdr, sizeof(req),
+ NULL, 0);
+ TEST_ASSERT(r == 0,
+ "KVMI_VCPU_SET_XSAVE failed with error %d (%s)\n",
+ -r, kvm_strerror(-r));
+}
+
+static void test_cmd_vcpu_xsave(struct kvm_vm *vm)
{
struct kvm_cpuid_entry2 *entry;
+ struct kvm_xsave xsave;
entry = kvm_get_supported_cpuid_entry(1);
if (!(entry->ecx & X86_FEATURE_XSAVE)) {
@@ -1577,7 +1595,8 @@ static void test_cmd_vcpu_get_xsave(struct kvm_vm *vm)
return;
}
- cmd_vcpu_get_xsave(vm);
+ cmd_vcpu_get_xsave(vm, &xsave);
+ cmd_vcpu_set_xsave(vm, &xsave);
}
static void test_introspection(struct kvm_vm *vm)
@@ -1608,7 +1627,7 @@ static void test_introspection(struct kvm_vm *vm)
test_cmd_vm_get_max_gfn();
test_event_xsetbv(vm);
test_cmd_vcpu_get_xcr(vm);
- test_cmd_vcpu_get_xsave(vm);
+ test_cmd_vcpu_xsave(vm);
unhook_introspection(vm);
}
diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h
index 26fc27f3fddc..f358ef1c0c73 100644
--- a/virt/kvm/introspection/kvmi_int.h
+++ b/virt/kvm/introspection/kvmi_int.h
@@ -111,5 +111,8 @@ int kvmi_arch_cmd_vcpu_get_xcr(struct kvm_vcpu *vcpu,
int kvmi_arch_cmd_vcpu_get_xsave(struct kvm_vcpu *vcpu,
struct kvmi_vcpu_get_xsave_reply **dest,
size_t *dest_size);
+int kvmi_arch_cmd_vcpu_set_xsave(struct kvm_vcpu *vcpu,
+ const struct kvmi_vcpu_set_xsave *req,
+ size_t req_size);
#endif
diff --git a/virt/kvm/introspection/kvmi_msg.c b/virt/kvm/introspection/kvmi_msg.c
index 06a8fbb5c86d..c8fe55c3d5c7 100644
--- a/virt/kvm/introspection/kvmi_msg.c
+++ b/virt/kvm/introspection/kvmi_msg.c
@@ -553,6 +553,22 @@ static int handle_vcpu_get_xsave(const struct kvmi_vcpu_msg_job *job,
return err;
}
+static int handle_vcpu_set_xsave(const struct kvmi_vcpu_msg_job *job,
+ const struct kvmi_msg_hdr *msg,
+ const void *req)
+{
+ size_t msg_size = msg->size, xsave_size;
+ int ec;
+
+ if (check_sub_overflow(msg_size, sizeof(struct kvmi_vcpu_hdr),
+ &xsave_size))
+ return -EINVAL;
+
+ ec = kvmi_arch_cmd_vcpu_set_xsave(job->vcpu, req, xsave_size);
+
+ return kvmi_msg_vcpu_reply(job, msg, ec, NULL, 0);
+}
+
/*
* These functions are executed from the vCPU thread. The receiving thread
* passes the messages using a newly allocated 'struct kvmi_vcpu_msg_job'
@@ -571,6 +587,7 @@ static int(*const msg_vcpu[])(const struct kvmi_vcpu_msg_job *,
[KVMI_VCPU_GET_XSAVE] = handle_vcpu_get_xsave,
[KVMI_VCPU_INJECT_EXCEPTION] = handle_vcpu_inject_exception,
[KVMI_VCPU_SET_REGISTERS] = handle_vcpu_set_registers,
+ [KVMI_VCPU_SET_XSAVE] = handle_vcpu_set_xsave,
};
static bool is_vcpu_command(u16 id)
