From: Marcelo Tosatti <mtosatti@redhat.com>
Add support for halt poll control MSR: save/restore, migration
and new feature name.
The purpose of this MSR is to allow the guest to disable
host halt poll.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Message-Id: <20190603230408.GA7938@amt.cnet>
[Do not enable by default, as pointed out by Mark Kanda. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
include/standard-headers/asm-x86/kvm_para.h | 2 ++
target/i386/cpu.c | 4 +++-
target/i386/cpu.h | 1 +
target/i386/kvm.c | 14 ++++++++++++++
target/i386/machine.c | 20 ++++++++++++++++++++
5 files changed, 40 insertions(+), 1 deletion(-)
diff --git a/include/standard-headers/asm-x86/kvm_para.h b/include/standard-headers/asm-x86/kvm_para.h
index 35cd8d6..e171514 100644
--- a/include/standard-headers/asm-x86/kvm_para.h
+++ b/include/standard-headers/asm-x86/kvm_para.h
@@ -29,6 +29,7 @@
#define KVM_FEATURE_PV_TLB_FLUSH 9
#define KVM_FEATURE_ASYNC_PF_VMEXIT 10
#define KVM_FEATURE_PV_SEND_IPI 11
+#define KVM_FEATURE_POLL_CONTROL 12
#define KVM_HINTS_REALTIME 0
@@ -47,6 +48,7 @@
#define MSR_KVM_ASYNC_PF_EN 0x4b564d02
#define MSR_KVM_STEAL_TIME 0x4b564d03
#define MSR_KVM_PV_EOI_EN 0x4b564d04
+#define MSR_KVM_POLL_CONTROL 0x4b564d05
struct kvm_steal_time {
uint64_t steal;
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 19751e3..9a8f244 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -906,7 +906,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
"kvmclock", "kvm-nopiodelay", "kvm-mmu", "kvmclock",
"kvm-asyncpf", "kvm-steal-time", "kvm-pv-eoi", "kvm-pv-unhalt",
NULL, "kvm-pv-tlb-flush", NULL, "kvm-pv-ipi",
- NULL, NULL, NULL, NULL,
+ "kvm-poll-control", NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
"kvmclock-stable-bit", NULL, NULL, NULL,
@@ -5660,6 +5660,8 @@ static void x86_cpu_initfn(Object *obj)
object_property_add_alias(obj, "kvm_steal_time", obj, "kvm-steal-time", &error_abort);
object_property_add_alias(obj, "kvm_pv_eoi", obj, "kvm-pv-eoi", &error_abort);
object_property_add_alias(obj, "kvm_pv_unhalt", obj, "kvm-pv-unhalt", &error_abort);
+ object_property_add_alias(obj, "kvm_poll_control", obj, "kvm-poll-control",
+ &error_abort);
object_property_add_alias(obj, "svm_lock", obj, "svm-lock", &error_abort);
object_property_add_alias(obj, "nrip_save", obj, "nrip-save", &error_abort);
object_property_add_alias(obj, "tsc_scale", obj, "tsc-scale", &error_abort);
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 8b3dc55..44e42f5 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1260,6 +1260,7 @@ typedef struct CPUX86State {
uint64_t steal_time_msr;
uint64_t async_pf_en_msr;
uint64_t pv_eoi_en_msr;
+ uint64_t poll_control_msr;
/* Partition-wide HV MSRs, will be updated only on the first vcpu */
uint64_t msr_hv_hypercall;
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index dbbb137..327c95a 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -1782,6 +1782,8 @@ void kvm_arch_reset_vcpu(X86CPU *cpu)
hyperv_x86_synic_reset(cpu);
}
+ /* enabled by default */
+ env->poll_control_msr = 1;
}
void kvm_arch_do_init_vcpu(X86CPU *cpu)
@@ -2490,6 +2492,11 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
if (env->features[FEAT_KVM] & (1 << KVM_FEATURE_STEAL_TIME)) {
kvm_msr_entry_add(cpu, MSR_KVM_STEAL_TIME, env->steal_time_msr);
}
+
+ if (env->features[FEAT_KVM] & (1 << KVM_FEATURE_POLL_CONTROL)) {
+ kvm_msr_entry_add(cpu, MSR_KVM_POLL_CONTROL, env->poll_control_msr);
+ }
+
if (has_architectural_pmu_version > 0) {
if (has_architectural_pmu_version > 1) {
/* Stop the counter. */
@@ -2875,6 +2882,9 @@ static int kvm_get_msrs(X86CPU *cpu)
if (env->features[FEAT_KVM] & (1 << KVM_FEATURE_STEAL_TIME)) {
kvm_msr_entry_add(cpu, MSR_KVM_STEAL_TIME, 0);
}
+ if (env->features[FEAT_KVM] & (1 << KVM_FEATURE_POLL_CONTROL)) {
+ kvm_msr_entry_add(cpu, MSR_KVM_POLL_CONTROL, 1);
+ }
if (has_architectural_pmu_version > 0) {
if (has_architectural_pmu_version > 1) {
kvm_msr_entry_add(cpu, MSR_CORE_PERF_FIXED_CTR_CTRL, 0);
@@ -3109,6 +3119,10 @@ static int kvm_get_msrs(X86CPU *cpu)
case MSR_KVM_STEAL_TIME:
env->steal_time_msr = msrs[i].data;
break;
+ case MSR_KVM_POLL_CONTROL: {
+ env->poll_control_msr = msrs[i].data;
+ break;
+ }
case MSR_CORE_PERF_FIXED_CTR_CTRL:
env->msr_fixed_ctr_ctrl = msrs[i].data;
break;
diff --git a/target/i386/machine.c b/target/i386/machine.c
index b114609..2ddd295 100644
--- a/target/i386/machine.c
+++ b/target/i386/machine.c
@@ -439,6 +439,14 @@ static const VMStateDescription vmstate_exception_info = {
}
};
+/* Poll control MSR enabled by default */
+static bool poll_control_msr_needed(void *opaque)
+{
+ X86CPU *cpu = opaque;
+
+ return cpu->env.poll_control_msr != 1;
+}
+
static const VMStateDescription vmstate_steal_time_msr = {
.name = "cpu/steal_time_msr",
.version_id = 1,
@@ -472,6 +480,17 @@ static const VMStateDescription vmstate_pv_eoi_msr = {
}
};
+static const VMStateDescription vmstate_poll_control_msr = {
+ .name = "cpu/poll_control_msr",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .needed = poll_control_msr_needed,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT64(env.poll_control_msr, X86CPU),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
static bool fpop_ip_dp_needed(void *opaque)
{
X86CPU *cpu = opaque;
@@ -1356,6 +1375,7 @@ VMStateDescription vmstate_x86_cpu = {
&vmstate_async_pf_msr,
&vmstate_pv_eoi_msr,
&vmstate_steal_time_msr,
+ &vmstate_poll_control_msr,
&vmstate_fpop_ip_dp,
&vmstate_msr_tsc_adjust,
&vmstate_msr_tscdeadline,
--
1.8.3.1