@@ -329,3 +329,47 @@
##
{ 'command': 'query-cpu-definitions', 'returns': ['CpuDefinitionInfo'],
'if': 'defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_I386) || defined(TARGET_S390X) || defined(TARGET_MIPS)' }
+
+##
+# @CpuidEntry:
+#
+# A single entry of a CPUID response.
+#
+# One entry holds full set of information (leaf) returned to the guest
+# in response to it calling a CPUID instruction with eax, ecx used as
+# the agruments to that instruction. ecx is an optional argument as
+# not all of the leaves support it.
+#
+# @in-eax: CPUID argument in eax
+# @in-ecx: CPUID argument in ecx
+# @eax: CPUID result in eax
+# @ebx: CPUID result in ebx
+# @ecx: CPUID result in ecx
+# @edx: CPUID result in edx
+#
+# Since: 6.2
+##
+{ 'struct': 'CpuidEntry',
+ 'data': { 'in-eax' : 'uint32',
+ '*in-ecx' : 'uint32',
+ 'eax' : 'uint32',
+ 'ebx' : 'uint32',
+ 'ecx' : 'uint32',
+ 'edx' : 'uint32'
+ },
+ 'if': 'defined(TARGET_I386)' }
+
+##
+# @query-x86-cpuid:
+#
+# Returns raw data from the emulated CPUID table for the first VCPU.
+# The emulated CPUID table defines the response to the CPUID
+# instruction when executed by the guest operating system.
+#
+# Returns: a list of CpuidEntry
+#
+# Since: 6.2
+##
+{ 'command': 'query-x86-cpuid',
+ 'returns': ['CpuidEntry'],
+ 'if': 'defined(TARGET_I386)' }
@@ -128,7 +128,7 @@ void hw_error(const char *fmt, ...)
/*
* The chosen accelerator is supposed to register this.
*/
-static const AccelOpsClass *cpus_accel;
+const AccelOpsClass *cpus_accel;
void cpu_synchronize_all_states(void)
{
@@ -12,6 +12,7 @@
#include "qemu/osdep.h"
#include "cpu.h"
#include "kvm_i386.h"
+#include "qapi/error.h"
#ifndef __OPTIMIZE__
bool kvm_has_smm(void)
@@ -39,3 +40,12 @@ bool kvm_hv_vpindex_settable(void)
{
return false;
}
+
+typedef struct CpuidEntryList CpuidEntryList;
+CpuidEntryList *qmp_query_x86_cpuid(Error **errp);
+
+CpuidEntryList *qmp_query_x86_cpuid(Error **errp)
+{
+ error_setg(errp, "Not implemented in --disable-kvm configuration");
+ return NULL;
+}
@@ -20,10 +20,12 @@
#include <linux/kvm.h>
#include "standard-headers/asm-x86/kvm_para.h"
+#include "qapi/qapi-commands-machine-target.h"
#include "cpu.h"
#include "sysemu/sysemu.h"
#include "sysemu/hw_accel.h"
+#include "sysemu/accel-ops.h"
#include "sysemu/kvm_int.h"
#include "sysemu/runstate.h"
#include "kvm_i386.h"
@@ -1464,6 +1466,51 @@ static Error *invtsc_mig_blocker;
#define KVM_MAX_CPUID_ENTRIES 100
+struct kvm_cpuid2 *cpuid_data_cached;
+extern const AccelOpsClass *cpus_accel;
+
+static inline int is_kvm_accel(AccelOpsClass *class)
+{
+ ObjectClass *parent_class;
+
+ parent_class = &class->parent_class;
+ return strcmp(object_class_get_name(parent_class),
+ "kvm-accel-ops") == 0;
+}
+
+CpuidEntryList *qmp_query_x86_cpuid(Error **errp)
+{
+ int i;
+ struct kvm_cpuid_entry2 *kvm_entry;
+ CpuidEntryList *head = NULL, **tail = &head;
+ CpuidEntry *entry;
+
+ if (!cpuid_data_cached) {
+ if (cpus_accel && !is_kvm_accel((AccelOpsClass *)cpus_accel))
+ error_setg(errp, "Not implemented for non-kvm accel");
+ else
+ error_setg(errp, "VCPU was not initialized yet");
+ return NULL;
+ }
+
+ for (i = 0; i < cpuid_data_cached->nent; ++i) {
+ kvm_entry = &cpuid_data_cached->entries[i];
+ entry = g_malloc0(sizeof(*entry));
+ entry->in_eax = kvm_entry->function;
+ if (kvm_entry->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) {
+ entry->in_ecx = kvm_entry->index;
+ entry->has_in_ecx = true;
+ }
+ entry->eax = kvm_entry->eax;
+ entry->ebx = kvm_entry->ebx;
+ entry->ecx = kvm_entry->ecx;
+ entry->edx = kvm_entry->edx;
+ QAPI_LIST_APPEND(tail, entry);
+ }
+
+ return head;
+}
+
int kvm_arch_init_vcpu(CPUState *cs)
{
struct {
@@ -1833,6 +1880,10 @@ int kvm_arch_init_vcpu(CPUState *cs)
if (r) {
goto fail;
}
+ if (!cpuid_data_cached) {
+ cpuid_data_cached = g_malloc0(sizeof(cpuid_data));
+ memcpy(cpuid_data_cached, &cpuid_data, sizeof(cpuid_data));
+ }
if (has_xsave) {
env->xsave_buf = qemu_memalign(4096, sizeof(struct kvm_xsave));
@@ -46,6 +46,7 @@ static int query_error_class(const char *cmd)
{ "query-balloon", ERROR_CLASS_DEVICE_NOT_ACTIVE },
{ "query-hotpluggable-cpus", ERROR_CLASS_GENERIC_ERROR },
{ "query-vm-generation-id", ERROR_CLASS_GENERIC_ERROR },
+ { "query-x86-cpuid", ERROR_CLASS_GENERIC_ERROR },
{ NULL, -1 }
};
int i;
Introducing new QMP command 'query-x86-cpuid'. This command can be used to get virtualized cpu model info generated by QEMU during VM initialization in the form of cpuid representation. Diving into more details about virtual CPU generation: QEMU first parses '-cpu' command line option. From there it takes the name of the model as the basis for feature set of the new virtual CPU. After that it uses trailing '-cpu' options, that state if additional cpu features should be present on the virtual CPU or excluded from it (tokens '+'/'-' or '=on'/'=off'). After that QEMU checks if the host's cpu can actually support the derived feature set and applies host limitations to it. After this initialization procedure, virtual CPU has it's model and vendor names, and a working feature set and is ready for identification instructions such as CPUID. To learn exactly how virtual CPU is presented to the guest machine via CPUID instruction, new QMP command can be used. By calling 'query-x86-cpuid' command, one can get a full listing of all CPUID leaves with subleaves which are supported by the initialized virtual CPU. Other than debug, the command is useful in cases when we would like to utilize QEMU's virtual CPU initialization routines and put the retrieved values into kernel CPUID overriding mechanics for more precise control over how various processes perceive its underlying hardware with container processes as a good example. The command is specific to x86. It is currenly only implemented for KVM acceleator. Output format: The output is a plain list of leaf/subleaf argument combinations, that return 4 words in registers EAX, EBX, ECX, EDX. Use example: qmp_request: { "execute": "query-x86-cpuid" } qmp_response: { "return": [ { "eax": 1073741825, "edx": 77, "in-eax": 1073741824, "ecx": 1447775574, "ebx": 1263359563 }, { "eax": 16777339, "edx": 0, "in-eax": 1073741825, "ecx": 0, "ebx": 0 }, { "eax": 13, "edx": 1231384169, "in-eax": 0, "ecx": 1818588270, "ebx": 1970169159 }, { "eax": 198354, "edx": 126614527, "in-eax": 1, "ecx": 2176328193, "ebx": 2048 }, .... { "eax": 12328, "edx": 0, "in-eax": 2147483656, "ecx": 0, "ebx": 0 } ] } Signed-off-by: Valeriy Vdovin <valeriy.vdovin@virtuozzo.com> --- v2: - Removed leaf/subleaf iterators. - Modified cpu_x86_cpuid to return false in cases when count is greater than supported subleaves. v3: - Fixed structure name coding style. - Added more comments - Ensured buildability for non-x86 targets. v4: - Fixed cpu_x86_cpuid return value logic and handling of 0xA leaf. - Fixed comments. - Removed target check in qmp_query_cpu_model_cpuid. v5: - Added error handling code in qmp_query_cpu_model_cpuid v6: - Fixed error handling code. Added method to query_error_class v7: - Changed implementation in favor of cached cpuid_data for KVM_SET_CPUID2 v8: - Renamed qmp method to query-kvm-cpuid and some fields in response. - Modified documentation to qmp method - Removed helper struct declaration v9: - Renamed 'in_eax' / 'in_ecx' fields to 'in-eax' / 'in-ecx' - Pasted more complete response to commit message. v10: - Subject changed - Fixes in commit message - Small fixes in QMP command docs v11: - Added explanation about CONFIG_KVM to the commit message. v12: - Changed title from query-kvm-cpuid to query-x86-cpuid - Removed CONFIG_KVM ifdefs - Added detailed error messages for some stub/unimplemented cases. v13: - Tagged with since 6.2 qapi/machine-target.json | 44 ++++++++++++++++++++++++++++++++ softmmu/cpus.c | 2 +- target/i386/kvm/kvm-stub.c | 10 ++++++++ target/i386/kvm/kvm.c | 51 ++++++++++++++++++++++++++++++++++++++ tests/qtest/qmp-cmd-test.c | 1 + 5 files changed, 107 insertions(+), 1 deletion(-)