(CC'ing qemu devel) 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 <mtosa...@redhat.com> 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 c1ab86d..1ca6944 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -903,7 +903,7 @@ 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, @@ -3001,6 +3001,7 @@ static PropValue kvm_default_props[] = { { "kvm-asyncpf", "on" }, { "kvm-steal-time", "on" }, { "kvm-pv-eoi", "on" }, + { "kvm-poll-control", "on" }, { "kvmclock-stable-bit", "on" }, { "x2apic", "on" }, { "acpi", "off" }, @@ -5660,6 +5661,8 @@ 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 bd06523..21ed2f8 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1241,6 +1241,7 @@ 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 3b29ce5..a5e9cdf 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -1369,6 +1369,8 @@ 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) @@ -2059,6 +2061,11 @@ 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. */ @@ -2443,6 +2450,9 @@ 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); @@ -2677,6 +2687,10 @@ 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 225b5d4..1c23e5e 100644 --- a/target/i386/machine.c +++ b/target/i386/machine.c @@ -323,6 +323,14 @@ static bool steal_time_msr_needed(void *opaque) return cpu->env.steal_time_msr != 0; } +/* 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, @@ -356,6 +364,17 @@ 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; @@ -1062,6 +1081,7 @@ 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,