kvm: i8254: require KVM_CAP_PIT2 and KVM_CAP_PIT_STATE2

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
qemu · Oct 25, 2023 · 39dd3e1 · 39dd3e1
1 parent 52b04ea
commit 39dd3e1
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Showing 4 changed files with 13 additions and 39 deletions.
diff --git a/hw/i386/kvm/i8254.c b/hw/i386/kvm/i8254.c
@@ -97,24 +97,12 @@ static void kvm_pit_get(PITCommonState *pit)
         return;
     }
 
-    if (kvm_has_pit_state2()) {
-        ret = kvm_vm_ioctl(kvm_state, KVM_GET_PIT2, &kpit);
-        if (ret < 0) {
-            fprintf(stderr, "KVM_GET_PIT2 failed: %s\n", strerror(-ret));
-            abort();
-        }
-        pit->channels[0].irq_disabled = kpit.flags & KVM_PIT_FLAGS_HPET_LEGACY;
-    } else {
-        /*
-         * kvm_pit_state2 is superset of kvm_pit_state struct,
-         * so we can use it for KVM_GET_PIT as well.
-         */
-        ret = kvm_vm_ioctl(kvm_state, KVM_GET_PIT, &kpit);
-        if (ret < 0) {
-            fprintf(stderr, "KVM_GET_PIT failed: %s\n", strerror(-ret));
-            abort();
-        }
+    ret = kvm_vm_ioctl(kvm_state, KVM_GET_PIT2, &kpit);
+    if (ret < 0) {
+        fprintf(stderr, "KVM_GET_PIT2 failed: %s\n", strerror(-ret));
+        abort();
     }
+    pit->channels[0].irq_disabled = kpit.flags & KVM_PIT_FLAGS_HPET_LEGACY;
     for (i = 0; i < 3; i++) {
         kchan = &kpit.channels[i];
         sc = &pit->channels[i];
@@ -170,12 +158,9 @@ static void kvm_pit_put(PITCommonState *pit)
         kchan->count_load_time = sc->count_load_time - s->kernel_clock_offset;
     }
 
-    ret = kvm_vm_ioctl(kvm_state,
-                       kvm_has_pit_state2() ? KVM_SET_PIT2 : KVM_SET_PIT,
-                       &kpit);
+    ret = kvm_vm_ioctl(kvm_state, KVM_SET_PIT2, &kpit);
     if (ret < 0) {
-        fprintf(stderr, "%s failed: %s\n",
-                kvm_has_pit_state2() ? "KVM_SET_PIT2" : "KVM_SET_PIT",
+        fprintf(stderr, "KVM_SET_PIT2 failed: %s\n",
                 strerror(-ret));
         abort();
     }
@@ -261,11 +246,12 @@ static void kvm_pit_realizefn(DeviceState *dev, Error **errp)
     };
     int ret;
 
-    if (kvm_check_extension(kvm_state, KVM_CAP_PIT2)) {
-        ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_PIT2, &config);
-    } else {
-        ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_PIT);
+    if (!kvm_check_extension(kvm_state, KVM_CAP_PIT_STATE2) ||
+        !kvm_check_extension(kvm_state, KVM_CAP_PIT2)) {
+        error_setg(errp, "In-kernel PIT not available");
     }
+
+    ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_PIT2, &config);
     if (ret < 0) {
         error_setg(errp, "Create kernel PIC irqchip failed: %s",
                    strerror(-ret));

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
@@ -1214,12 +1214,8 @@ void pc_basic_device_init(struct PCMachineState *pcms,
 
     /*
      * Check if an HPET shall be created.
-     *
-     * Without KVM_CAP_PIT_STATE2, we cannot switch off the in-kernel PIT
-     * when the HPET wants to take over. Thus we have to disable the latter.
      */
-    if (pcms->hpet_enabled && (!kvm_irqchip_in_kernel() ||
-                               kvm_has_pit_state2())) {
+    if (pcms->hpet_enabled) {
         qemu_irq rtc_irq;
 
         hpet = qdev_try_new(TYPE_HPET);

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
@@ -145,7 +145,6 @@ static uint32_t num_architectural_pmu_fixed_counters;
 
 static int has_xsave2;
 static int has_xcrs;
-static int has_pit_state2;
 static int has_sregs2;
 static int has_exception_payload;
 static int has_triple_fault_event;
@@ -162,11 +161,6 @@ static KVMMSRHandlers msr_handlers[KVM_MSR_FILTER_MAX_RANGES];
 static RateLimit bus_lock_ratelimit_ctrl;
 static int kvm_get_one_msr(X86CPU *cpu, int index, uint64_t *value);
 
-bool kvm_has_pit_state2(void)
-{
-    return !!has_pit_state2;
-}
-
 bool kvm_has_smm(void)
 {
     return kvm_vm_check_extension(kvm_state, KVM_CAP_X86_SMM);
@@ -2543,7 +2537,6 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     }
 
     has_xcrs = kvm_check_extension(s, KVM_CAP_XCRS);
-    has_pit_state2 = kvm_check_extension(s, KVM_CAP_PIT_STATE2);
     has_sregs2 = kvm_check_extension(s, KVM_CAP_SREGS2) > 0;
 
     hv_vpindex_settable = kvm_check_extension(s, KVM_CAP_HYPERV_VP_INDEX);

diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h
@@ -33,7 +33,6 @@
 bool kvm_has_smm(void);
 bool kvm_enable_x2apic(void);
 bool kvm_hv_vpindex_settable(void);
-bool kvm_has_pit_state2(void);
 
 bool kvm_enable_sgx_provisioning(KVMState *s);
 bool kvm_hyperv_expand_features(X86CPU *cpu, Error **errp);